I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts to
adapt it for more height, so I can load and unload taller things out of the
back of my truck.

Referencing the picture in the link above. What if I removed the existing
boom and cylinder, installed 2 hand crank winches where the existing boom
mounts, and installed a longer boom where the existing hydraulic cylinder
mounts at the bottom end? The new boom might be made of channel iron, cut
and welded with some angle to "curve" the boom for object clearance. The
desired end result would be to stand the boom to where the load would be in
the same range that it is in the existing configuration but give high enough
lift to load and unload items from a pickup truck, maybe even off the back
of a semi.

Oh, the 2 hand winches, one controls boom angle, the other lifts the load,
snatch blocks could be used to half the speed and double the force. This
configuration would be less idiot proof since someone could lower the boom,
getting the load beyond the wheels, and flip the thing.

But all in all it might be easier to make an adapter for the existing boom
so it could be angled closer to vertical, and use a longer extendable boom,
then just add a winch and pulley.

Either way it should be a simple matter to go from engine hoist to a taller
crane by changing a few parts around.

RogerN

I would not do it, you will bend the vertical post and that will be
the end of it.

I have a 2 ton Harbor Freight crane with telescoping legs (not
foldable), and it was perfectly high enough to take stuff out of my
pickup truck.

If I was in your situation, I would extend the boom a little, add a
counterweight on the back, and lift less weight than allowed, to
account for longer boom.

i

On 2012-02-05, RogerN wrote:

I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts to
adapt it for more height, so I can load and unload taller things out of the
back of my truck.

Referencing the picture in the link above. What if I removed the existing
boom and cylinder, installed 2 hand crank winches where the existing boom
mounts, and installed a longer boom where the existing hydraulic cylinder
mounts at the bottom end? The new boom might be made of channel iron, cut
and welded with some angle to "curve" the boom for object clearance. The
desired end result would be to stand the boom to where the load would be in
the same range that it is in the existing configuration but give high enough
lift to load and unload items from a pickup truck, maybe even off the back
of a semi.

Oh, the 2 hand winches, one controls boom angle, the other lifts the load,
snatch blocks could be used to half the speed and double the force. This
configuration would be less idiot proof since someone could lower the boom,
getting the load beyond the wheels, and flip the thing.

But all in all it might be easier to make an adapter for the existing boom
so it could be angled closer to vertical, and use a longer extendable boom,
then just add a winch and pulley.

Either way it should be a simple matter to go from engine hoist to a taller
crane by changing a few parts around.

RogerN

"RogerN" wrote in message
...

I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts
to adapt it for more height, so I can load and unload taller things out of
the back of my truck.

RogerN

Mine has tipped over a few times at its original 9' max height.

You can decrease the wasted headroom above bulky sling loads by attaching a
load leveler to the tip of the boom as a spreader.
http://www.harborfreight.com/2-ton-c...eler-5402.html

Be very careful that the load doesn't swing when you roll the crane back. If
a projected line from the hook down through its center of gravity passes
outside the wheelbase it can pull the crane over.

My experience with consumer-grade rigging and hoisting equipment suggests
that it has little or no margin and if modified should be derated
substantially and if possible proof tested with a load cell.

jsw

On 2012-02-05, Jim Wilkins wrote:

"RogerN" wrote in message
...

I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts
to adapt it for more height, so I can load and unload taller things out of
the back of my truck.

RogerN

Mine has tipped over a few times at its original 9' max height.

I recommend not ever moving anything that is suspended well above
ground level.

My procedure was, put a crane in place, back under a crane, lift the
load, get the truck out, lower it down (preferably on boards placed
across feet), then move the crane.

I almost tipped the crane once, also.

i

You can decrease the wasted headroom above bulky sling loads by attaching a
load leveler to the tip of the boom as a spreader.
http://www.harborfreight.com/2-ton-c...eler-5402.html

Be very careful that the load doesn't swing when you roll the crane back. If
a projected line from the hook down through its center of gravity passes
outside the wheelbase it can pull the crane over.

My experience with consumer-grade rigging and hoisting equipment suggests
that it has little or no margin and if modified should be derated
substantially and if possible proof tested with a load cell.

jsw

"Ignoramus15251" wrote in message
...

I would not do it, you will bend the vertical post and that will be
the end of it.

I have a 2 ton Harbor Freight crane with telescoping legs (not
foldable), and it was perfectly high enough to take stuff out of my
pickup truck.

If I was in your situation, I would extend the boom a little, add a
counterweight on the back, and lift less weight than allowed, to
account for longer boom.

i

My engine hoist lifts short items out of the truck OK, but didn't work for
my lathe (reaching to center of gravity over the lathe) or my vertical air
compressor, having 4WD truck doesn't help.

Currently the vertical post has a hydraulic jack attached, either 5 ton or 8
ton. I don't see that attaching a boom to that point and running it mostly
vertical, keeping the load within the range of the wheels, is going to
increase the bending forces on the vertical post. My goal is to increase
the vertical height, not the load rating or ability to reach further out.
The tension from the hoist cables would be attached very near the support
braces, this would put the braces in tension just as they are currently when
lifting.

But if somehow having a long boom attached to where the bottom of the
hydraulic cylinder currently attaches would cause more bending force on the
vertical post, what about the current configuration with the boom lengthened
and pointed up near vertical? For example if a 1000lb load was out 24" from
the vertical post, a horizontal boom X component would be 1 (COS of zero
degrees), if that same load was still 24" out but the boom was 60 degrees,
the X component would be 0.5 but on a longer boom. I'm not saying the load
capacity would be exactly the same but it would be nice if I could unload
taller item from my pickup truck and perhaps even items from a tractor
trailer truck. Of course if I get a shop built here and get my forklift
moved over here it won't be an issue.

RogerN

Here's a crane constructed similar to the engine hoist type.

http://www.youtube.com/watch?v=F3h6jVbS2_k

RogerN

"Ignoramus15251" wrote in message
...
On 2012-02-05, Jim Wilkins wrote:
Mine has tipped over a few times at its original 9' max height.

I recommend not ever moving anything that is suspended well above
ground level.

My procedure was, put a crane in place, back under a crane, lift the
load, get the truck out, lower it down (preferably on boards placed
across feet), then move the crane.

I almost tipped the crane once, also.
i

I used the crane that way as a trailer to haul a half-ton boulder out back
into the woods. Straddle it, lift it, slide in planks and lower. Larger
wheels turn them into nice self-loading utility trailers. They are top-heavy
when empty, though.

My mast-end caster and trailer tongue:
https://picasaweb.google.com/KB1DAL/...51034176921634
The coupler is on the end of the wood handle.

A coupler rigidly attached to the base would work better for towing because
I could back it up and the tractor's weight would counterbalance the load on
the extended boom. I still need the long wood caster-steering handle to
maneuver it manually though, and both need to occupy the same space.

The problem is when only the crane can move, like erecting a timber frame,
pulling the engine from a wheel-less wrecked car or moving the raised deck
away from an above-ground pool. It's difficult to keep the wheels on planks
that rest on uneven ground.

I dropped a Weld-and-Power because the driver parked bumper to a tree to
leave maneuvering room behind, and it swung when we pulled hard enough to
start my crane rolling on the gravel. It didn't drop far, but afterwards he
listened to me.

jsw

You would have liked the OTC crane that I sold. It could lift 6000 lbs
to about 10 feet, or 4000 lbs to 14 feet.

http://yabe.chudov.com/OTC-1814-Elec...draulic-Crane/

I sold it because I have forklifts.

i

On 2012-02-05, RogerN wrote:

Here's a crane constructed similar to the engine hoist type.

http://www.youtube.com/watch?v=F3h6jVbS2_k

RogerN

"RogerN" wrote in message
m...

Here's a crane constructed similar to the engine hoist type.

http://www.youtube.com/watch?v=F3h6jVbS2_k

RogerN

I admit that I've concocted stuff like that but don't want to describe it
and get anyone hurt. I wouldn't do it if I didn't have load cells to proof
test it. Friends who see it will want to borrow it, and likely be less
careful than you.

Can you find a higher place to put the crane instead of modifying it? (hint,
hint)

I didn't have any trouble lifting an Atlas lathe in or out of my truck with
a Homier bed-mounted crane.

jsw

RogerN wrote:
I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts to
adapt it for more height, so I can load and unload taller things out of the
back of my truck.

Referencing the picture in the link above. What if I removed the existing
boom and cylinder, installed 2 hand crank winches where the existing boom
mounts, and installed a longer boom where the existing hydraulic cylinder
mounts at the bottom end? The new boom might be made of channel iron, cut
and welded with some angle to "curve" the boom for object clearance. The
desired end result would be to stand the boom to where the load would be in
the same range that it is in the existing configuration but give high enough
lift to load and unload items from a pickup truck, maybe even off the back
of a semi.

Oh, the 2 hand winches, one controls boom angle, the other lifts the load,
snatch blocks could be used to half the speed and double the force. This
configuration would be less idiot proof since someone could lower the boom,
getting the load beyond the wheels, and flip the thing.

But all in all it might be easier to make an adapter for the existing boom
so it could be angled closer to vertical, and use a longer extendable boom,
then just add a winch and pulley.

Either way it should be a simple matter to go from engine hoist to a taller
crane by changing a few parts around.

RogerN


http://www.harborfreight.com/automot...ane-41188.html


--
Steve W.

On Sun, 5 Feb 2012 10:10:48 -0600, "RogerN" wrote:


I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts to
adapt it for more height, so I can load and unload taller things out of the
back of my truck.

You are hoisting very heavy things over yourself as you are
unloading them - things that fall and crush people on a regular
basis...

DON'T **** WITH MURPHY, HE WILL BITE YOU. If you modify that engine
hoist to extend the reach or the load ratings you are going where even
professional engineers fear to tread, and you will have to totally own
any accidents that happen.

Go buy/rent/borrow a gantry crane, a trolley and a good chain-fall or
electric hoist for lifting your loads out of the bed of the truck -
http://www.harborfreight.com/1-ton-t...ane-41188.html
http://www.harborfreight.com/1-ton-p...ley-97392.html

Northern Tool has a whole assortment of Vestil gantry cranes in an
assortment of sizes in both adjustable and fixed height up to 8000#
load ratings, and all the trolleys and hoists too.

And McMaster, Grainger and the other A-List suppliers have varying
width and height gantries that go to 10,000# and beyond, but you pay.
Even "Easy Store" ones that break down and assemble by hand with Dzus
Pins, can be slid into the back of a pickup or stuck in a corner when
not in use. Biggest piece is the load beam, and all Aluminum.

Put the gantry over the truck, lift the load, then drive the truck out
from under it. Then you can lower the load into final position, or
onto a set of machinery moving skates where you can horse it into
final position. And for loading, you do the opposite.

Even with a wheeled gantry you still don't try moving a load swinging
from the hook alone - it gets tippy, the load starts swinging, things
go bad really fast.

You get the load on the ground, then you use a fortklift or pallet
jack or those machinery skate wheels to make horizontal moves.

-- Bruce --

On 2012-02-05, Bruce L. Bergman (munged human readable) wrote:
On Sun, 5 Feb 2012 10:10:48 -0600, "RogerN" wrote:


I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts to
adapt it for more height, so I can load and unload taller things out of the
back of my truck.

You are hoisting very heavy things over yourself as you are
unloading them - things that fall and crush people on a regular
basis...

DON'T **** WITH MURPHY, HE WILL BITE YOU. If you modify that engine
hoist to extend the reach or the load ratings you are going where even
professional engineers fear to tread, and you will have to totally own
any accidents that happen.

Go buy/rent/borrow a gantry crane, a trolley and a good chain-fall or
electric hoist for lifting your loads out of the bed of the truck -
http://www.harborfreight.com/1-ton-t...ane-41188.html
http://www.harborfreight.com/1-ton-p...ley-97392.html

Northern Tool has a whole assortment of Vestil gantry cranes in an
assortment of sizes in both adjustable and fixed height up to 8000#
load ratings, and all the trolleys and hoists too.

And McMaster, Grainger and the other A-List suppliers have varying
width and height gantries that go to 10,000# and beyond, but you pay.
Even "Easy Store" ones that break down and assemble by hand with Dzus
Pins, can be slid into the back of a pickup or stuck in a corner when
not in use. Biggest piece is the load beam, and all Aluminum.

Put the gantry over the truck, lift the load, then drive the truck out
from under it. Then you can lower the load into final position, or
onto a set of machinery moving skates where you can horse it into
final position. And for loading, you do the opposite.

Even with a wheeled gantry you still don't try moving a load swinging
from the hook alone - it gets tippy, the load starts swinging, things
go bad really fast.

You get the load on the ground, then you use a fortklift or pallet
jack or those machinery skate wheels to make horizontal moves.

-- Bruce --

I think that he was trying to find a solution that does not cost as
much money.

Also, lifting stuff out of a truck is not overhead lifting.

i

On Sun, 05 Feb 2012 15:35:45 -0600, Ignoramus15251
wrote:


I think that he was trying to find a solution that does not cost as
much money.

Also, lifting stuff out of a truck is not overhead lifting.

It most certainly is unless you have a Telepresence rig on your hoist
- otherwise if you are manually cranking that winch up to take the
load you are standing well within splat range when the load falls.

You need to be a good 20' away to get out of the range of flying
pieces that break off and fly at rather high velocities. And you
really don't want to be close enough for it to land on your legs.

If you really need cheap, you can get raw steel and build your own
gantry, or back the loaded truck under a Really Stout Oak Tree.

Or you call the friend at the Tow Truck Company and send the recovery
boom wrecker over. Nice safe big 10,000 pound (or more) boom hoist
(sometimes a Double Boom) with a power winch and everything, and it
only costs you gas money and a case of good beer.

Roll-off wreckers are good for short-distance machinery moving from
Point A to B - even if you need the recovery boom to get the lathe on
and off the flatbed.

Or you go rent a small crane or something at the local U-Rent place.
If you don't have to do this very often, that pays. If you need it
every week, break down and get a gantry.

"Ignoramus15251" wrote in message
...


I think that he was trying to find a solution that does not cost as
much money.

Also, lifting stuff out of a truck is not overhead lifting.

i

I'm kind of wanting to experiment around a bit too. I'm thinking of making
steel sockets that will fit over a pair of 2 X 4's for a boom. By hooking
up the winch cables to the steel ends I should be able to keep all bending
forces off the 2 X 4's so they are only in compression. I can test with
various weights and figure it's save at about 2/3's the maximum test weight.
The idea would be to make a truck mount crane that can have interchangeable
booms, shorter for heavy loads and longer for light loads with long reach,
or taller lifts.

I've looked at some manuals on commercial manual cranes, pdf files. The
weight rating seems to be with the distance horizontal, not vertical. For
example one with a maximum 2000 with the boom in horizontal shortest length
has a rating of 1200 lbs with the boom extended to the maximum. However
with the boom angled up to the maximum, the lift rating is 2000 lbs at the
maximum extended position. This seems to agree with the calculations in the
rigging manual that the steeper the boom is, the less the amount of force is
on the guy wires and the greater the force is in compression on the boom.

All in all the cherry picker is pretty much just a C frame with the load in
the opposite direction of a C clamp. I think the force on the frame of a C
clamp is more related to throat depth than it is opening distance. That's
why I don't think my rearrangement would destroy the vertical post as long
as I don't exceed the load for the horizontal distance of the original boom.
I do think t would be much easier to tip over though.

RogerN

On Sun, 5 Feb 2012 10:10:48 -0600, "RogerN" wrote:


I have an engine hoist similar to this one:
http://www.ruralking.com/engine-hois...m-midwest.html

It's useful within it's range but I was thinking about making some parts to
adapt it for more height, so I can load and unload taller things out of the
back of my truck.

You might be better off making a wooden gantry crane. Some call them
a "lifting horse" like a giant saw horse. There are several ideas on
lifting things in this post at Practical Machinist:
http://www.practicalmachinist.com/vb...5-post1553677/

Make sure you click on the "more replies below" in the list of
messages at the top of the web page in order to see all the replies.

The one that Forest Addy describes has 4x4 legs and a 4x8 cross member
around 10' long. Unfortunately no pictures of the ones he made. I
wondered about the bracing from the legs to the cross piece.

wrote in message ...

You might be better off making a wooden gantry crane. Some call them
a "lifting horse" like a giant saw horse. There are several ideas on
lifting things in this post at Practical Machinist:
http://www.practicalmachinist.com/vb...5-post1553677/

Make sure you click on the "more replies below" in the list of
messages at the top of the web page in order to see all the replies.

The one that Forest Addy describes has 4x4 legs and a 4x8 cross member
around 10' long. Unfortunately no pictures of the ones he made. I
wondered about the bracing from the legs to the cross piece.

I lifted my 13" X 7' bed South Bend lathe from my pole barn's roof truss
lower chord without any problem. A wooden A-frame is definitely on my wish
list unless I find an I-beam first. I thought I might make a wooden I beam
using a 2 X 10 center and 2 X 4's on top and bottom. That's much more wood
than I used to lower my lathe, I think it would handle all except maybe my
largest mill (estimated 4,500 lbs).

The gantry would be great for unloading stuff at home but I'd also like
something portable to be able to go and pick up an item. I've been thinking
about some sort of crane that could be quickly assembled using a receiver
hitch and perhaps some trailer jacks for outriggers. The engine hoist to
portable crane is one possibility but takes up a lot of truck bed space and
needs a smooth surface to roll.

RogerN

GeoLane at PTD dot NET wrote in message
...

You might be better off making a wooden gantry crane. Some call them
a "lifting horse" like a giant saw horse. There are several ideas on
lifting things in this post at Practical Machinist:
http://www.practicalmachinist.com/vb...5-post1553677/

The one that Forest Addy describes has 4x4 legs and a 4x8 cross member
around 10' long. Unfortunately no pictures of the ones he made. I
wondered about the bracing from the legs to the cross piece.

I assembled a temporary one like that with laminated 2x4 legs in an A with
center post, and channel irons for the track, bolted together with the end
attachment plates and diagonal braces sandwiched between them.

The casters were trailer tongue jacks. They wouldn't roll with the load
suspended so I lowered the ends to move the load with the trolley, then
raised them to reposition the gantry. New England glacial till is firm
enough that we don't need to pave all our trails and work areas, but small
wheels still don't roll well on it.

This is the channel and the end support geometry, minus a diagonal brace
that isn't needed he
https://picasaweb.google.com/KB1DAL/...88504883032706

Two legs in an A require less material; with three like that you don't have
to cut up the ends and can leave them full length and reuse them elsewhere.
The post is a carefully selected 3"x5" landscaping timber and the braces are
two 2" pipe legs of a neighbor's engine pulling tripod that he gave me after
a truck ran over and bent the third one, and I told him I had the shop
crane.

One long shoulder bolt holds everything together at the top. The track hangs
on a turnbuckle that levels it. That photo was taken before I drilled the
extra holes in the web for the diagonal braces that the free-standing gantry
version needs.

Erecting that much weight overhead is tricky, one hand holds the steel while
the other slides in the bolt, which I taper to help alignment. I slide
boards across the next-to-top rungs of a z-folding ladder and balance the
two channels on them, then raise and attach the end support(s). When it's
secure I pull out the planks and lift the ladder off over the channels.
Reverse to disassemble. This limits the height of the gantry beam to the
size of my ladder, but I probably couldn't slide the channels into place on
a much taller ladder anyway.

That is 3" channel iron (surplus pallet rack) I bought for sawmill track.
It's adequate for logs but heavier stock would be better for machinery.

jsw

Just my $.02:
Don't do it. I am one of those who had the thing tip over, even without
modifications.
Other posters have commented about the weight swinging from side to side
and upsetting things.
You haven't lived until you have had that happen. A 1500 pound pendulum can
do a lot of damage.

Pete Stanaitis
---------------

"Pete S" wrote in message
.. .
Just my $.02:
Don't do it. I am one of those who had the thing tip over, even without
modifications.
Other posters have commented about the weight swinging from side to side
and upsetting things.
You haven't lived until you have had that happen. A 1500 pound pendulum
can do a lot of damage.

Pete Stanaitis

Several times including this morning I have written and then deleted a
description of how to make a lightweight portable collapsible gantry lift
with the beam suspended from folding tripods.

I didn't post them because mine have collapsed at the wrong time, and can
fall in any direction, so don't do it.

jsw

I understand the replies about safety and how it would become unstable with
the load able to swing outside the wheel area and cause the crane to tip
over, etc. But, since this is a metalworking newsgroup, and most cranes
that I know of, including the 60 ton crane we have at work, are constructed
using metalworking, I don't agree with the replies that say I shouldn't do
it.

Instead of a reply like- "don't do it, it would be too easy to tip over", I
would think a better reply would be to advise adding outriggers to prevent
it from tipping over. The video to the Easy-Rig cranes show a crane
constructed similar to the cherry pickers but the "legs" spread wider and
out further for more stability. This being a metalworking group, and most
crane construction involves metalworking, not recommending doesn't seem to
fit in. I can design for the weight I want to be able to lift with a
sufficient design factor, then test out to 150% of the load I want to rate
the crane for. Like recommended, I can get a crane load cell and scale head
to test weight at different angles & positions.

I do realize the cherry picker as it is would be easy to tip over with a
tall boom, either from a high height load with a slight tip or a low height
load with a lot of cable, allowing the load to swing outside of the area of
the base. I'm thinking a better idea may be to make an A-frame gantry for
heavy lifts and a portable crane that could be stabilized through the
receiver hitch of my truck and perhaps an outrigger trailer jack. This
would work to load the truck and I could use the A-frame to unload at home.

RogerN

On 2012-02-09, RogerN wrote:

I understand the replies about safety and how it would become unstable with
the load able to swing outside the wheel area and cause the crane to tip
over, etc. But, since this is a metalworking newsgroup, and most cranes
that I know of, including the 60 ton crane we have at work, are constructed
using metalworking, I don't agree with the replies that say I shouldn't do
it.

Instead of a reply like- "don't do it, it would be too easy to tip over", I
would think a better reply would be to advise adding outriggers to prevent
it from tipping over. The video to the Easy-Rig cranes show a crane
constructed similar to the cherry pickers but the "legs" spread wider and
out further for more stability. This being a metalworking group, and most
crane construction involves metalworking, not recommending doesn't seem to
fit in. I can design for the weight I want to be able to lift with a
sufficient design factor, then test out to 150% of the load I want to rate
the crane for. Like recommended, I can get a crane load cell and scale head
to test weight at different angles & positions.

I do realize the cherry picker as it is would be easy to tip over with a
tall boom, either from a high height load with a slight tip or a low height
load with a lot of cable, allowing the load to swing outside of the area of
the base. I'm thinking a better idea may be to make an A-frame gantry for
heavy lifts and a portable crane that could be stabilized through the
receiver hitch of my truck and perhaps an outrigger trailer jack. This
would work to load the truck and I could use the A-frame to unload at home.

RogerN



So, go ahead and do it, and use the crane to lift the weight that you
think it should be capable of lifting, as a test. Report your
findings.

i

"RogerN" wrote in message
m...

I understand the replies about safety and how it would become unstable
with
the load able to swing outside the wheel area and cause the crane to tip
over, etc. But, since this is a metalworking newsgroup, and most cranes
that I know of, including the 60 ton crane we have at work, are
constructed
using metalworking, I don't agree with the replies that say I shouldn't do
it.

RogerN

I don't want to hear from your estate's lawyer about how you killed yourself
by following my advice. We gave you some general guidelines and problems to
watch out for, the specific details and liability are your responsibility.

Examine commercial products and try to reconstruct and understand their
engineering decisions, including the dimensions, stresses and factor of
safety. I did before designing my bucket loader. A textbook on Statics helps
enormously. If that's too much effort, at least film the project for reality
TV.

zeoru qwc49

On Sun, 5 Feb 2012 19:03:33 -0600, "RogerN" wrote:

"Ignoramus15251" wrote in message
m...


I think that he was trying to find a solution that does not cost as
much money.

Also, lifting stuff out of a truck is not overhead lifting.

i

I'm kind of wanting to experiment around a bit too. I'm thinking of making
steel sockets that will fit over a pair of 2 X 4's for a boom. By hooking
up the winch cables to the steel ends I should be able to keep all bending
forces off the 2 X 4's so they are only in compression. I can test with
various weights and figure it's save at about 2/3's the maximum test weight.
The idea would be to make a truck mount crane that can have interchangeable
booms, shorter for heavy loads and longer for light loads with long reach,
or taller lifts.

I've looked at some manuals on commercial manual cranes, pdf files. The
weight rating seems to be with the distance horizontal, not vertical. For
example one with a maximum 2000 with the boom in horizontal shortest length
has a rating of 1200 lbs with the boom extended to the maximum. However
with the boom angled up to the maximum, the lift rating is 2000 lbs at the
maximum extended position. This seems to agree with the calculations in the
rigging manual that the steeper the boom is, the less the amount of force is
on the guy wires and the greater the force is in compression on the boom.

All in all the cherry picker is pretty much just a C frame with the load in
the opposite direction of a C clamp. I think the force on the frame of a C
clamp is more related to throat depth than it is opening distance. That's
why I don't think my rearrangement would destroy the vertical post as long
as I don't exceed the load for the horizontal distance of the original boom.
I do think t would be much easier to tip over though.

The main message sent by the crowd is "Be CAREFUL with this!"

You're messing with something that could kill you if you screw it up
just right, and can easily mess up your load and anything that was
underneath or nearby, you gotta approach this with that in mind.

That said, you could make a longer main-post and rear braces, change
the angle a little bit so the upper arm hinge point is in the same
plane, and make some side-facing outriggers to reduce the tipping
chances.

But up the steel gauge on that main post another notch, as you are
increasing the stresses on it. And no shortcuts - nice multiple pass
welds with good penetration. And if you don't trust your welding or
don't have a big enough machine to do it right, just tack it together
and have someone who lays down big beads every day do the real
welding.

I wouldn't mess with the lifting arm ratings or geometry at all, or
moving the fulcrum point for the hoist cylinder.

-- Bruce --

Bruce, what you offer is a well written generic safety message. "be
careful modifying things and also, when lifted, things might fall, and
if you stand under things that fall, they will fall on you, and you
need a lot of expensive doodads and well paid engineers to be OSHA
compliant".

It is hard to argue with this.

What Roger is trying, though, is NOT overhead lifting, and he is just
trying to get stuff out of his pickup truck.

What I personally think is a more specific opinion, that Roger's
modification will end up bending the vertical post if used at full
capacity.

In any case, I think, if he wants to go ahead, he should, it is his
right, but he should test the crane at his planned capacity, very
carefully.

i


On 2012-02-09, Bruce L. Bergman (munged human readable) wrote:
On Sun, 5 Feb 2012 19:03:33 -0600, "RogerN" wrote:

"Ignoramus15251" wrote in message
om...


I think that he was trying to find a solution that does not cost as
much money.

Also, lifting stuff out of a truck is not overhead lifting.

i

I'm kind of wanting to experiment around a bit too. I'm thinking of making
steel sockets that will fit over a pair of 2 X 4's for a boom. By hooking
up the winch cables to the steel ends I should be able to keep all bending
forces off the 2 X 4's so they are only in compression. I can test with
various weights and figure it's save at about 2/3's the maximum test weight.
The idea would be to make a truck mount crane that can have interchangeable
booms, shorter for heavy loads and longer for light loads with long reach,
or taller lifts.

I've looked at some manuals on commercial manual cranes, pdf files. The
weight rating seems to be with the distance horizontal, not vertical. For
example one with a maximum 2000 with the boom in horizontal shortest length
has a rating of 1200 lbs with the boom extended to the maximum. However
with the boom angled up to the maximum, the lift rating is 2000 lbs at the
maximum extended position. This seems to agree with the calculations in the
rigging manual that the steeper the boom is, the less the amount of force is
on the guy wires and the greater the force is in compression on the boom.

All in all the cherry picker is pretty much just a C frame with the load in
the opposite direction of a C clamp. I think the force on the frame of a C
clamp is more related to throat depth than it is opening distance. That's
why I don't think my rearrangement would destroy the vertical post as long
as I don't exceed the load for the horizontal distance of the original boom.
I do think t would be much easier to tip over though.

The main message sent by the crowd is "Be CAREFUL with this!"

You're messing with something that could kill you if you screw it up
just right, and can easily mess up your load and anything that was
underneath or nearby, you gotta approach this with that in mind.

That said, you could make a longer main-post and rear braces, change
the angle a little bit so the upper arm hinge point is in the same
plane, and make some side-facing outriggers to reduce the tipping
chances.

But up the steel gauge on that main post another notch, as you are
increasing the stresses on it. And no shortcuts - nice multiple pass
welds with good penetration. And if you don't trust your welding or
don't have a big enough machine to do it right, just tack it together
and have someone who lays down big beads every day do the real
welding.

I wouldn't mess with the lifting arm ratings or geometry at all, or
moving the fulcrum point for the hoist cylinder.

-- Bruce --

On Feb 9, 6:52*am, "RogerN" wrote:
I understand the replies about safety and how it would become unstable with
the load able to swing outside the wheel area and cause the crane to tip
over, etc. *But, since this is a metalworking newsgroup, and most cranes
that I know of, including the 60 ton crane we have at work, are constructed
using metalworking, I don't agree with the replies that say I shouldn't do
it.


RogerN


i think people are saying if you have to ask for advice here, you are
not really up to modifying a engine hoist.

In industry when making a modification to a lifting device, you are
required to get the original manufacturer to sign off on the
modification. I was not in the group that did those sorts of things,
but I think it is an OSHA requirement.


Dan

On Thu, 09 Feb 2012 10:56:24 -0600, Ignoramus13761
wrote:

Bruce, what you offer is a well written generic safety message. "be
careful modifying things and also, when lifted, things might fall, and
if you stand under things that fall, they will fall on you, and you
need a lot of expensive doodads and well paid engineers to be OSHA
compliant".

It is hard to argue with this.

What Roger is trying, though, is NOT overhead lifting, and he is just
trying to get stuff out of his pickup truck.

Oh, it's not "Overhead Lifting", is it?

What color is the Sun on your home planet?

Do you have an engine hoist like this, Iggy? Good! Now go out back,
remove the tailgate on your pickup and set up the engine hoist just
like you would if you were going to pick an engine block out of the
back of your pickup truck.

Take the pump handle, insert it in the jack pump socket, and grab hold
of the pump handle on the lifting ram like you're lifting the load...

Quick Quiz: B WHERE THE F*** ARE YOU STANDING?? /B

Your arm is within a foot of that boom - your head and body, two feet
max. Unless you modify it with an Air-Over-Hydraulic jack, and then
you can back off maybe 3' or 4' - any more and you can't keep control
of the load.

Yes, it's not technically "Overhead" lifting - but for purposes of
operational safety it might as well be.

Remember, you might have only been lifting 1 ton, but there's a
reason the Jack on the engine hoist is rated at 8 Tons or more -
Leverage. Lots of it, and in several directions.

If that engine hoist chose that moment to come apart, all the pieces
that break and had a ton of load and up to 8 tons of force applied on
them are going to shoot off in various and unpredictable directions.

Little things like the main arm hinge bolt that sheared off can have
killing velocities for a few feet and can embed in a wall up to about
10' to 20' away. And the hoist arm and upright have more than enough
mass + velocity to break an arm, or a leg, or shatter your skull.

The load is most likely going straight DOWN - but it can bounce, roll,
slide or do other unpredictable things when it gets to another hard
surface, and if the lifting arm is partially intact it could influence
the load into swinging down in an arc... And any limb that gets in
the way (or portion thereof) is getting crushed.

Don't pooh-pooh this - it's serious ****.

And you don't want it anywhere near the fan, when it hits you'll know.

-- Bruce --

On 2012-02-09, Bruce L. Bergman (munged human readable) wrote:
On Thu, 09 Feb 2012 10:56:24 -0600, Ignoramus13761
wrote:

Bruce, what you offer is a well written generic safety message. "be
careful modifying things and also, when lifted, things might fall, and
if you stand under things that fall, they will fall on you, and you
need a lot of expensive doodads and well paid engineers to be OSHA
compliant".

It is hard to argue with this.

What Roger is trying, though, is NOT overhead lifting, and he is just
trying to get stuff out of his pickup truck.

Oh, it's not "Overhead Lifting", is it?

Nope.

What color is the Sun on your home planet?

Do you have an engine hoist like this, Iggy? Good! Now go out back,
remove the tailgate on your pickup and set up the engine hoist just
like you would if you were going to pick an engine block out of the
back of your pickup truck.

Take the pump handle, insert it in the jack pump socket, and grab hold
of the pump handle on the lifting ram like you're lifting the load...

Quick Quiz: B WHERE THE F*** ARE YOU STANDING?? /B

To the side.

Your arm is within a foot of that boom - your head and body, two feet
max. Unless you modify it with an Air-Over-Hydraulic jack, and then
you can back off maybe 3' or 4' - any more and you can't keep control
of the load.

Yes, it's not technically "Overhead" lifting - but for purposes of
operational safety it might as well be.

No, it is not.

Remember, you might have only been lifting 1 ton, but there's a
reason the Jack on the engine hoist is rated at 8 Tons or more -
Leverage. Lots of it, and in several directions.

Actually, not a ton, just 1,000 lbs.

If that engine hoist chose that moment to come apart, all the pieces
that break and had a ton of load and up to 8 tons of force applied on
them are going to shoot off in various and unpredictable directions.

Little things like the main arm hinge bolt that sheared off can have
killing velocities for a few feet and can embed in a wall up to about
10' to 20' away. And the hoist arm and upright have more than enough
mass + velocity to break an arm, or a leg, or shatter your skull.

I do not see, how the bolt can get sheared by that sheetmetal.

The load is most likely going straight DOWN - but it can bounce, roll,
slide or do other unpredictable things when it gets to another hard
surface, and if the lifting arm is partially intact it could influence
the load into swinging down in an arc... And any limb that gets in
the way (or portion thereof) is getting crushed.

It is not that unpredictable and not nearly as violent. It would just
come down at a few feet per second max.

Don't pooh-pooh this - it's serious ****.

And you don't want it anywhere near the fan, when it hits you'll know.

-- Bruce --

I am not agreeing with what Roger wants to do, for other reasons, but
if the crane is used properly, its failure would have mild
consequences.

In article ,
Ignoramus13761 wrote:

Bruce, what you offer is a well written generic safety message. "be
careful modifying things and also, when lifted, things might fall, and
if you stand under things that fall, they will fall on you, and you
need a lot of expensive doodads and well paid engineers to be OSHA
compliant".

It is hard to argue with this.

What Roger is trying, though, is NOT overhead lifting, and he is just
trying to get stuff out of his pickup truck.

What I personally think is a more specific opinion, that Roger's
modification will end up bending the vertical post if used at full
capacity.

In any case, I think, if he wants to go ahead, he should, it is his
right, but he should test the crane at his planned capacity, very
carefully.

At capacity? Not even close. Test at about four times stated capacity.
No matter how good an engineer/welder one may be.

Joe Gwinn

I found some info on proof testing modified lifting equipment.

http://www.hq.nasa.gov/office/codeq/...led/1740_9.pdf
Proof Load Test. Before first use, all new, extensively repaired,
extensively
modified, or altered cranes and derricks shall undergo a proof load test. A
proof load test also should be performed when there is a question in design
or
previous testing. Mobile cranes and derricks shall be tested at the minimum
working radius (and maximum working radius for new cranes and derricks
only) with a load as close as possible to, but not exceeding 1.10 times the
rated load at the given radius. The load shall be lifted slowly and in an
area
where minimal damage will occur if the crane/derrick fails. The minimum
radius/maximum load capacity of the crane/derrick shall be clearly marked to
be legible from the operator's or user's position and shall not be more than
the proof test weight divided by 1.10. For cranes/derricks with separate
lifting systems of different ratings, the markings will indicate the lifting
capabilities of each system (e.g., main hook, whip hook, and auxiliary
hook).
Proof load tests conducted by the manufacturer prior to delivery are
acceptable if the necessary test certification papers are provided to verify
the
extent and thoroughness of the test on that specific item.

My cherry picker is rated at 4000 lbs at the shortest boom length. I don't
plan to ever lift more than 1000 lbs if I modify the lift to a crane.
According to the above, for a 1000 lb rating I should test at 1100 lbs. If
I needed to lift heavier I would test to 110% of whatever weight I wanted to
lift. I also found some info stating that the minimum design factor should
be 3.0, doesn't sound like a bad place to start.

RogerN

On 2012-02-10, Joseph Gwinn wrote:
In article ,
Ignoramus13761 wrote:

Bruce, what you offer is a well written generic safety message. "be
careful modifying things and also, when lifted, things might fall, and
if you stand under things that fall, they will fall on you, and you
need a lot of expensive doodads and well paid engineers to be OSHA
compliant".

It is hard to argue with this.

What Roger is trying, though, is NOT overhead lifting, and he is just
trying to get stuff out of his pickup truck.

What I personally think is a more specific opinion, that Roger's
modification will end up bending the vertical post if used at full
capacity.

In any case, I think, if he wants to go ahead, he should, it is his
right, but he should test the crane at his planned capacity, very
carefully.

At capacity? Not even close. Test at about four times stated capacity.
No matter how good an engineer/welder one may be.

Joe Gwinn

Cranes are not tested at four times capacity.

i

"Joseph Gwinn" wrote
Ignoramus13761 wrote:

In any case, I think, if he wants to go ahead, he should, it is his
right, but he should test the crane at his planned capacity, very
carefully.

At capacity? Not even close. Test at about four times stated capacity.
No matter how good an engineer/welder one may be.

Joe Gwinn

The recommendation I've seen is to load a qualification test sample to 4X
but proof the identical working model(s) to 2X. For example 3/8" Grade 70
chain has a WLL 0f 6600 Lbs, proof test of 13,200 and minimum breaking force
of 26,400.
http://www.nacm.info/Downloads/NACM%20_Welded_Specs.pdf

But first you need a load cell. Mine, from an auction, was still expensive
at 5% of list price. The dial indicator readout makes it almost too fragile
to survive field use. Do NOT ask to borrow it.

HF seems to have discontinued the 440 Lb Big Game Scale. Maybe you could
rework the sensors and display from a bathroom scale???

jsw

"RogerN" wrote in message
m...
..
My cherry picker is rated at 4000 lbs at the shortest boom length. I
don't plan to ever lift more than 1000 lbs if I modify the lift to a
crane. According to the above, for a 1000 lb rating I should test at 1100
lbs. If I needed to lift heavier I would test to 110% of whatever weight
I wanted to lift. I also found some info stating that the minimum design
factor should be 3.0, doesn't sound like a bad place to start.

RogerN

Good that you are researching it. For me the minimum requirements are the
load cell to test and the Statics textbook to learn the failure mechanisms,
some of which may not be evident to you like web shear, beam crippling and
the Euler limit.

Do what you want, but don't expect written approval.

jsw

"Jim Wilkins" wrote in message ...

The recommendation I've seen is to load a qualification test sample to 4X
but proof the identical working model(s) to 2X. For example 3/8" Grade 70
chain has a WLL 0f 6600 Lbs, proof test of 13,200 and minimum breaking
force of 26,400.
http://www.nacm.info/Downloads/NACM%20_Welded_Specs.pdf

But first you need a load cell. Mine, from an auction, was still expensive
at 5% of list price. The dial indicator readout makes it almost too fragile
to survive field use. Do NOT ask to borrow it.

HF seems to have discontinued the 440 Lb Big Game Scale. Maybe you could
rework the sensors and display from a bathroom scale???

jsw

Cable, wire rope, seems to have a wll of 1/5th the breaking strength, rope
about 1/10 because of knots weakening the rope. Hoists are recommended to
be tested at 110% per multiple documents I've found on websites.

I'm curious about your load cell, what capacity? What price at 5% of list.
I've saw new 20,000lb load cells on eBay for the $150 range IIRC. Is yours
mechanical or does it have strain gauges for electronic scale readers? You
can make your own load cells but the scale needs to be calibrated. I was
the project tech for a machine with 35 load cells so I got pretty familiar
with load cells, testing, troubleshooting, how to make them work when you
have no replacements, etc. So, if I so desire I can machine some load
cells, Omega sells the strain gauges, I can take them to work for
calibration, they have calibration weights in thousands of pounds for their
silo's and truck scales.

Anyway, proper testing of a crane is definitely within my reach, and I like
the idea of around a 4.0 design factor and a 110% or more test. With the
$20 load cell chip I have I can create a million pound scale with ounce
resolution, though it realistically wouldn't be that accurate, it would be
plenty good for testing 110% of a known load. I can make a plenty good
enough scale using a voltmeter and an instrumentation amplifier.

If I get time in the near future I hope to test, I plan to try to lift the
rear of my truck (4X4 Ford Ranger 4.0) with a crane constructed of a two
2X4"s.

RogerN

"Jim Wilkins" wrote in message ...

Good that you are researching it. For me the minimum requirements are the
load cell to test and the Statics textbook to learn the failure mechanisms,
some of which may not be evident to you like web shear, beam crippling and
the Euler limit.

Do what you want, but don't expect written approval.

jsw

I understand, it can be dangerous, I plan to test in a hopefully safe
manner. Most times I feel more in danger driving on the road with idiots
than anything I do that I can control. It seems odd that the army manuals
can achieve more lift with a couple of timbers, pulleys, and rope than
metalworkers can with steel, welders, hydraulics, & winches.

RogerN

"Bruce L. Bergman (munged human readable)" wrote in message
...

But up the steel gauge on that main post another notch, as you are
increasing the stresses on it. And no shortcuts - nice multiple pass
welds with good penetration. And if you don't trust your welding or
don't have a big enough machine to do it right, just tack it together
and have someone who lays down big beads every day do the real
welding.

I wouldn't mess with the lifting arm ratings or geometry at all, or
moving the fulcrum point for the hoist cylinder.

-- Bruce --

I have a little over 400A AC/DC TIG/Stick for welding at my home shop,
should be enough for a small (1/2-1 ton) crane.

RogerN

"RogerN" wrote in message
m...

"Jim Wilkins" wrote in message ...
...Do NOT ask to borrow it.
jsw


I'm curious about your load cell, what capacity? What price at 5% of
list. I've saw new 20,000lb load cells on eBay for the $150 range IIRC.
Is yours mechanical or does it have strain gauges for electronic scale
readers?

5000 Lbs, $50, long out of calibration.
You can see the construction:
http://www.dillon-force.com/literatu...08595-0012.pdf

It's a lab instrument, OK on a crane, not happy at all bouncing around on a
chain in the woods.

jsw

"Ignoramus4275" wrote in message
...

On 2012-02-09, RogerN wrote:
snip
I'm thinking a better idea may be to make an A-frame gantry for
heavy lifts and a portable crane that could be stabilized through the
receiver hitch of my truck and perhaps an outrigger trailer jack. This
would work to load the truck and I could use the A-frame to unload at
home.

RogerN


So, go ahead and do it, and use the crane to lift the weight that you
think it should be capable of lifting, as a test. Report your
findings.

i

I found a picture of what I like for the truck mounted crane

http://img223.imageshack.us/img223/7...bc95cbfwh5.jpg

My truck has a bed liner and I don't want to cut it up trying to bolt to the
frame of the truck. If I could support the crane with outriggers to take
the load and stabilize it with the truck I think it would do what I want. I
don't have hopes of loading Bridgeport's in the back of my Ford Ranger but a
crane like that could probably load anything that I wouldn't need a trailer
for.

RogerN

"RogerN" wrote in message
m...

I found a picture of what I like for the truck mounted crane

http://img223.imageshack.us/img223/7...bc95cbfwh5.jpg

My truck has a bed liner and I don't want to cut it up trying to bolt to
the frame of the truck. If I could support the crane with outriggers to
take the load and stabilize it with the truck I think it would do what I
want. I don't have hopes of loading Bridgeport's in the back of my Ford
Ranger but a crane like that could probably load anything that I wouldn't
need a trailer for.

RogerN

I have a similar one mounted on crossbeams that attach to the four rear bed
bolts, so no changes to the Ranger. It's rated for 1000 Lbs but the truck
suspension limits it to about 700 because of the extra moment arm when the
load is out to the rear, and the front crossbeam is too thin to take much
more. I use its deflection as the full-load indicator.

As a rough field measure, 1000 lbs in the bed drops the fenders to one
clenched fist above the tires. Even observing that limit I've already broken
and replaced the rubber stops.

It's the low style, like HF #1647. I added a winch, boom-tip pulley and a
drop-on extension to the mast to clear light bulky loads like washing
machines. It has loaded an Atlas lathe without the mast extension.

I remove the bed liner, install the crossbeams and line the floor between
and ahead with plywood to use the crane. LPS3 has kept the bedliner latch
screws turning freely since 1992. The bed is also secured by 3/8" screw eyes
down into the filled-in stake pockets.

Gotta go, town meeting today, much to deliberate and vote on.

jsw

On 2012-02-11, RogerN wrote:
"Ignoramus4275" wrote in message
...

On 2012-02-09, RogerN wrote:
snip
I'm thinking a better idea may be to make an A-frame gantry for
heavy lifts and a portable crane that could be stabilized through the
receiver hitch of my truck and perhaps an outrigger trailer jack. This
would work to load the truck and I could use the A-frame to unload at
home.

RogerN


So, go ahead and do it, and use the crane to lift the weight that you
think it should be capable of lifting, as a test. Report your
findings.

i

I found a picture of what I like for the truck mounted crane

http://img223.imageshack.us/img223/7...bc95cbfwh5.jpg

My truck has a bed liner and I don't want to cut it up trying to bolt to the
frame of the truck. If I could support the crane with outriggers to take
the load and stabilize it with the truck I think it would do what I want. I
don't have hopes of loading Bridgeport's in the back of my Ford Ranger but a
crane like that could probably load anything that I wouldn't need a trailer
for.

I have a crane in the back of my pickup. I did drill holes in the bed
and used a large 5/8" steel plate to distribute the load. Two days
ago, I used it to lift a 1000 lbs generator into my truck.

I used to have a similar (to the one you showed) crane, but no longer,
now I have a Ramco 2500 lbs crane. I do realize that I cannot lift the
full amount with it.

i

On Sat, 11 Feb 2012 07:33:36 -0500, "Jim Wilkins"
wrote:


"RogerN" wrote in message
om...

I found a picture of what I like for the truck mounted crane

http://img223.imageshack.us/img223/7...bc95cbfwh5.jpg

My truck has a bed liner and I don't want to cut it up trying to bolt to
the frame of the truck. If I could support the crane with outriggers to
take the load and stabilize it with the truck I think it would do what I
want. I don't have hopes of loading Bridgeport's in the back of my Ford
Ranger but a crane like that could probably load anything that I wouldn't
need a trailer for.

RogerN

I have a similar one mounted on crossbeams that attach to the four rear bed
bolts, so no changes to the Ranger. It's rated for 1000 Lbs but the truck
suspension limits it to about 700 because of the extra moment arm when the
load is out to the rear, and the front crossbeam is too thin to take much
more. I use its deflection as the full-load indicator.

As a rough field measure, 1000 lbs in the bed drops the fenders to one
clenched fist above the tires. Even observing that limit I've already broken
and replaced the rubber stops.

Have you considered air bags? http://www.airbagit.com/ Then, if you
really overload the truck, it'll break the frame instead of the stops.



It's the low style, like HF #1647. I added a winch, boom-tip pulley and a
drop-on extension to the mast to clear light bulky loads like washing
machines. It has loaded an Atlas lathe without the mast extension.

Amazing! I had that style in my old F-150, and sold it with the
truck. (I got $1300 for the 17 y/o beastie?!)

--
Energy and persistence alter all things.
--Benjamin Franklin