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Default gantry - channel sections

Hi Jim - starting topic's own thread...

"Jim Wilkins" writes:

"Richard Smith" wrote in message ...

"Jim Wilkins" writes:

"Richard Smith" wrote in message
...
...



...

The samples in your tester are similar to my centrally spliced gantry
hoist track problem. I'm trying to determine where to best locate
splice plate bolts so their holes minimally weaken the four 4" x 5.4
channels that comprise the track. Maybe along the web's neutral axis,
if the web has sufficient bearing strength or I weld on
reinforcements?

Another possibility is welding loose-pin hinge leaves under the lower
flanges to take the tension.
https://en.wikipedia.org/wiki/Knuckle_joint_(mechanical)


I'd like to help you with this, if I can.
Sorry - been preoccupied getting the "testing" thing going

I'll see if can find past articles where you describe the issue.
Do you have a webpage you post pictures and articles to - like I do?
So I can see what you mean?

Regards,
Rich Smith
--------------------------------

So far what I have is four 8' sections of 4" x 5.4 lbs/ft channel
iron, which are former pallet rack shelf supports, and a Harbor
Freight gantry hoist trolley to run on them when bolted back-to-back
like an I beam.
https://www.harborfreight.com/1-ton-...ley-97392.html

I built a lighter version from four 8' sections of 3" channel, with
two hung back-to-back from the front and rear roof beams of a storage
shed and two more making a temporary track extension out over the path
past the shed, where I set up the sawmill and load logs and beams
to/from a narrow trailer. The moving overhead hoist is very useful to
move logs onto the sawmill bed and adjust the partly sawn cants, by
suspending them in a loop of nylon rope hung on a pulley so I can
easily turn and level them. The rolling bandsaw mill head needs nearly
8' of clearance between the shed and the track's outer end support
post

That part works quite well for 8' oak logs and 6" square beams for
shed columns. I have to set up the overhead extension track by my self
and one channel's weight is near the max that I can maneuver with one
hand while inserting bolts with the other. Safe handling and a
shortage of covered storage space are why I don't use a single 16'
beam (~240 lbs) for the track.

The problem is 12' logs for roof beams, which could overload the 3"
channel and won't fit the 10' deep shed. I have another shed 19' long
by 4' wide that can hold 12' beams if I hang a crosswise travelling
hoist from its roof to move them in. It contains some already, which I
moved by an unsatisfactory temporary arrangement of the 3" extension
channels. I'd like to run the 4" channels out 8' over the sawmill to a
braced post beyond it and in through the shed plus 4' out the far side
to another post, for lifting logs off the trailer. In that case the
track will be centrally supported from above at the joint between its
8' sections, no problem.

The extreme case is joining the four sections to make one 16' gantry
track hung from tripods at the ends, perhaps to load a bulky appliance
onto a truck. I may never need it but I'd like to find a center splice
joint design that doesn't exclude or conflict with the central
mounting from the shed roof beam. Hopefully one design will work for
both centrally and end supported cases. That knuckle joint under the
tension flanges looks good because I could raise the ground-assembled
track by it and then lift and level the two outer ends separately, and
it won't transfer sag on one side into lift on the other, and shift a
shed column off its footing. I don't quite know how to design one to
weld onto the channel flanges, for instance how much to taper the
leaves to distribute the elongation and weld shear stress.

Specifically I'd like to know if bolts in tapped holes in the upper
flange can be considered part of the compression area and the accepted
way to reinforce the holes for splicing plate bolts through the
channel web. Does the reinforcement need to be diamond shaped to avoid
vertical welds?

Since I'm not on the clock I can customize bolts on the lathe and
hand-fit them with minimal clearance. They are all Grade 8, fine
thread, 150KSI.


Hi Jim

Can you sketch?
That is always helpful. I do that even when it seems we all agree, as
it can be amazing how a sketch reveals that the impressions are not
the same.

I'm thinking - maybe weld some brackets on top of the channel with the
bolted flange faces facing.
I'd normally wish there could also be a flange underneath - but the
close-fitting "standard" carriage would collide with it, so not
possible.

That said: if I understand correctly (big "if") - the loading may be
"cantilever beam" - tension on top, compression underneath.
Extending out of the shed?
Suspended - near the door?
In which case flange on top, nothing needed underneath as compresses
together would be bril.

Load analysis of the section - as channels tend to twist under load,
and is singular, I wouldn't dare use Euler-Bernoulli beam calculation
as works for symmetrical beams.

Sorry verbal description is hard to "see".

Rich S

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Default gantry - channel sections

"Richard Smith" wrote in message ...

Hi Jim - starting topic's own thread...



Hi Jim

Can you sketch?
That is always helpful. I do that even when it seems we all agree, as
it can be amazing how a sketch reveals that the impressions are not
the same.

I'm thinking - maybe weld some brackets on top of the channel with the
bolted flange faces facing.
I'd normally wish there could also be a flange underneath - but the
close-fitting "standard" carriage would collide with it, so not
possible.

That said: if I understand correctly (big "if") - the loading may be
"cantilever beam" - tension on top, compression underneath.
Extending out of the shed?
Suspended - near the door?
In which case flange on top, nothing needed underneath as compresses
together would be bril.

Load analysis of the section - as channels tend to twist under load,
and is singular, I wouldn't dare use Euler-Bernoulli beam calculation
as works for symmetrical beams.

Sorry verbal description is hard to "see".

Rich S

-----------------------------

The channels will be attached web to web, with the splice plate sandwiched
between them at the center, hanger plates between them at the ends and other
stiffening as needed, so they should behave as a single symmetrical I beam.
So far the 3" channel track hasn't noticeably twisted under a 1/2 ton load.

Any cantilever loading will be the channel's own weight while setting up
plus possibly the weight of one end post and diagonal braces if the opposite
loaded side post sinks into wet ground. The model is a beam with pinned
joints to columns at the ends. Assume the columns are pinned at the base and
could tilt inward if the beam sags, though they won't tilt out or laterally.

Really I just need a good bolt geometry for the splice plate so I can start
calculating stresses. I'm leaning toward two large bolts through the
channels' neutral axes beside the joint and two more at the outer ends of
the vertical splice plate, and welding reinforcements to the web around them
if necessary. Perhaps a grid pattern of more smaller bolts would be better?

It seems to me that the beam splices I've seen on bridges might weaken the
lower flanges if the bolts aren't sufficiently tight, and this track must be
disassembled repeatedly and probably sprayed with slippery rust inhibitor
wax. The splice plate I have now, from a local steel erector's scrap pile,
is 10mm thick, 150mm high and 700mm long.

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"Richard Smith" wrote in message ...

Can you sketch?

---------------

If you send me an email I'll attach a photo of the gantry and sawmill. it's
on Google Photos but I don't know how to share it.

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Default gantry - channel sections

Jim Wilkins wrote:
"Richard Smith" wrote in message ...

Can you sketch?

---------------

If you send me an email I'll attach a photo of the gantry and sawmill. it's
on Google Photos but I don't know how to share it.


Right click on photo, select "Copy link address"
Paste link in new message.


--
Steve W.
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"Steve W." wrote in message ...

Jim Wilkins wrote:
"Richard Smith" wrote in message
...

Can you sketch?

---------------

If you send me an email I'll attach a photo of the gantry and sawmill.
it's on Google Photos but I don't know how to share it.


Right click on photo, select "Copy link address"
Paste link in new message.
-----------------------------------------
https://photos.google.com/photo/AF1Q...KNJpqIL_Xendex



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Default gantry - channel sections

"Jim Wilkins" writes:

"Steve W." wrote in message ...

Jim Wilkins wrote:
"Richard Smith" wrote in message
...

Can you sketch?

---------------

If you send me an email I'll attach a photo of the gantry and
sawmill. it's on Google Photos but I don't know how to share it.


Right click on photo, select "Copy link address"
Paste link in new message.
-----------------------------------------
https://photos.google.com/photo/AF1Q...KNJpqIL_Xendex


Jim - get an "Error 404" on trying to follow that URL.
Tried immediately to get there and found that problem.
Sorry didn't get back to you immediately.
If U-channels are used symmetrically - back to back or facing - so
that they can't twist (rotate) under loading - that a simple analysis
just using 2nd moment of area, beam metal yield strength and beam
length/support is useful.
That also applies to "L" sections, by the way - facing or
back-to-back. In a "desperate" situation I worked out the strengths
according to Euler-Bernoulli beam and it seemed very right. As the
welder, I made sure the secondary steelwork was less strong (would
warn by taking permanent bend) and less stiff than the "primary"
steelwork - so you sensed the limit - and it worked so well.

If you still would like some additional input / collaboration on this,
we can try again with pix and dimensions.

I've done my best with "ASCII art" to sketch a buttressed bolted
connection.
That only works if the beam is cantilever, with the top in tension and
the bottom in compression.
The wheels of the carriage have clearance under the buttress
arrangement.


_ _
/ |_| \
---------------/--|_|--\---------------

------------------- -------------------

Which I think will be stiff and strong.
You could trap a "hanger plate" protruding out of the top as the
means to suspend the transporter beam.

I hope I have
* understood the situation
* the suggestion is helpful

Best wishes,
Rich Smith
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Default gantry - channel sections

"Richard Smith" wrote in message ...

"Jim Wilkins" writes:

"Steve W." wrote in message ...

Jim Wilkins wrote:
"Richard Smith" wrote in message
...

Can you sketch?

---------------

If you send me an email I'll attach a photo of the gantry and
sawmill. it's on Google Photos but I don't know how to share it.

Right click on photo, select "Copy link address"
Paste link in new message.
-----------------------------------------
https://photos.google.com/photo/AF1Q...KNJpqIL_Xendex


Jim - get an "Error 404" on trying to follow that URL.
-----
I could access it later the day it was posted, but not now. It shows the overall saw and gantry setup though not any detail.

My plan is to sandwich plates between the channels like this: ]|[.
The end plates are the hangers, the central one the splice plus a hanger when the track runs across the storage shed. I'll try single bolts through the web at the joint between the channels and at the outer ends of the splice, to see if the shear and bearing are reasonable.

This is in Courier New 10
_ _____________________ _
|o| / o \ splice |o|
====~~=============,================~~=====
|o o o | o o channels o|
====~~============='================~~=====

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"Richard Smith" wrote in message ...

"Jim Wilkins" writes:

---------------

I just found these to study:
https://www.steelconstruction.info/The_Green_Books

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"Jim Wilkins" writes:

"Richard Smith" wrote in message ...

"Jim Wilkins" writes:

---------------

I just found these to study:
https://www.steelconstruction.info/The_Green_Books


I regularly use the "Blue Book" for sections.
Didn't know of the "Green Books" for connections. Thanks.
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"Richard Smith" wrote in message ...

"Jim Wilkins" writes:

"Richard Smith" wrote in message
...

"Jim Wilkins" writes:

---------------

I just found these to study:
https://www.steelconstruction.info/The_Green_Books


I regularly use the "Blue Book" for sections.
Didn't know of the "Green Books" for connections. Thanks.

------------------------------------

This is very good too:
http://www.boltcouncil.org/files/2ndEditionGuide.pdf



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"Jim Wilkins" wrote in message ...

I've returned to the gantry track splice, after fixing the car to pass
inspection and largely completing my taxes.

Have you ever seen a bolted I beam splice with the flanges thickened with
welded plates or such to compensate for the reduction in area at the bolt
holes?

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"Jim Wilkins" wrote in message ...

"Jim Wilkins" wrote in message ...

I've returned to the gantry track splice, after fixing the car to pass
inspection and largely completing my taxes.

Have you ever seen a bolted I beam splice with the flanges thickened with
welded plates or such to compensate for the reduction in area at the bolt
holes?

--------------------------

If welding plates on the outside of the channel flanges to thicken and
strengthen them at the central splice is technically (if not economically)
sound, they provide much more thread engagement for splice plate bolts in
tapped holes, that don't interfere with the trolley wheels rolling on the
lower flange.

All the examples I've found of bolted beam splices accept the loss of net
flange area at the bolt holes and instead suggest locating the splices away
from the most heavily stressed parts of the beam.

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On Tue, 23 Mar 2021 09:19:51 -0400
"Jim Wilkins" wrote:

If welding plates on the outside of the channel flanges to thicken and
strengthen them at the central splice is technically (if not economically)
sound, they provide much more thread engagement for splice plate bolts in
tapped holes, that don't interfere with the trolley wheels rolling on the
lower flange.

All the examples I've found of bolted beam splices accept the loss of net
flange area at the bolt holes and instead suggest locating the splices away
from the most heavily stressed parts of the beam.


A patent here that uses wedges or teeth on plates and beams that would
transfer stress over a broader area:

https://patents.google.com/patent/US20030129026A1/en

Maybe poke around in the patents for a bit, give you some more ideas to
work with...

--
Leon Fisk
Grand Rapids MI

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"Leon Fisk" wrote in message ...

On Tue, 23 Mar 2021 09:19:51 -0400
"Jim Wilkins" wrote:

If welding plates on the outside of the channel flanges to thicken and
strengthen them at the central splice is technically (if not economically)
sound, they provide much more thread engagement for splice plate bolts in
tapped holes, that don't interfere with the trolley wheels rolling on the
lower flange.

All the examples I've found of bolted beam splices accept the loss of net
flange area at the bolt holes and instead suggest locating the splices away
from the most heavily stressed parts of the beam.


A patent here that uses wedges or teeth on plates and beams that would
transfer stress over a broader area:

https://patents.google.com/patent/US20030129026A1/en

Maybe poke around in the patents for a bit, give you some more ideas to
work with...

--
Leon Fisk
Grand Rapids MI

-----------------------------------------

From my reading it appears that a properly designed, prepared and torqued
slip-critical splice joint is as strong as the undrilled flanges, due to
friction around the bolts. One suggested preparation is to wire brush the
loose rust off by hand, but not with a power brush which makes the surfaces
too smooth.

I expect to have to customize the bolts to ensue their shear planes pass
through the full shank diameter, IOW extend the threads up a longer shank
and cut the bolt short, so I want them and their tapped holes reuseable and
won't tighten them anywhere near the yield point. Also the rust inhibitor I
use on outdoor steel and galvy dries to a soft wax that works fairly well as
a high pressure lubricant. The splice will have to depend on bolt shear and
bearing.

That grooved pattern is used to locate top jaws for lathe chucks. I've
considered other proven interlocking patterns such as the Christmas tree
that retains turbine blades and the doll's head on double shotguns. I don't
have CNC and doubt I could mill them accurately enough to share the load and
keep the splice from sagging. However I can custom-fit bolts tightly enough
to keep the joint snug and straight, as on my 3" gantry and sawmill's track.

I think I could make and weld on a multi-leaf knuckle joint (pinned hinge)
though its height would require a custom lowered bar between the trolley
side plates.

Incidentally, while researching bolt and rivet patterns I found that Titanic
was joined with strong steel rivets in the center but softer hand-set
wrought iron ones at the end where the hydraulic riveter wouldn't fit:
https://www.gjenvick.com/OceanTravel...gTheHulls.html

There is survivor testimony and sonar evidence that the hull plate seam(s)
opened from near the bow to all the way back to the forward coal bunker in
boiler room 5, half way between the first and second funnels, and possibly
into the piping space below the floor in boiler room 4 behind it, at the
base of the second funnel. A gap that long that averages the width of a
finger would account for the rate of flooding. Such extensive hull breaches
flood modern passenger ships, namely the Costa Concordia and Mikhail
Lermontov. (DUH!)

Britannic, the last of the trio, was modified during construction to cure
Titanic's flaws. Nevertheless, during WW1 she hit a mine, was damaged in the
same places, and sank twice as fast.

Olympic, the first, survived two of the normally expected ship-to-ship
collisions, smacking into huge immobile white icebergs being either very
rare or a cause of mysterious unexplained all-hands losses. The second was
with an attacking U-boat that slid under the hull into the propellers,
though some of its crew lived. Olympic was dinged but didn't leak and
remained in service well into the Depression.

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"Leon Fisk" wrote in message ...
....
A patent here that uses wedges or teeth on plates and beams that would
transfer stress over a broader area:
....

-----------------------------

I don't have the shop space to clamp one end of an 8' beam in my mill vise
to accurately drill a hole pattern. All I can do is hang the opposite end at
an angle in a doorway and locate a punch mark or pilot hole under the
spindle to drill it larger. The splice plate will have to be match-drilled
to beams on sawhorses out in the driveway. Either a Portalign or clamped-on
bench drill press will keep the bit, hole and tap square to the surface. I
use an adjustable hand reamer to give bolt shanks the minimum of clearance.

That's how I spliced 8' sections of 3" channel into the sawmill track and
overhead gantry, but those splices have to sustain only the dead weight of
the channels while I'm setting up and leveling them, they are supported at
the splice in service. I'm trying to splice the 4" channel strongly enough
that it doesn't need a center support although it will normally have one.
The problem is designing a tension-side joint that gives the full strength
of the channel without blocking the trolley.
https://www.harborfreight.com/1-ton-...ley-97392.html

If I just weld them together or buy a suitable 16' beam the assembly is too
large to store under cover and too heavy to carry and lift into place. One
8' section of the 4" channel is hard enough to support and align with one
hand while inserting a bolt with the other, on a stepladder. When possible I
turn a taper and a root-diameter pilot on the ends of machine screws to help
align tapped and clearance holes in things I repeatedly assemble and
disassemble outdoors, like my 50' TV antenna mast, but there isn't enough
clearance for that between the trolley wheels.

The problem could be worse. I had the chance to examine and ride in a Beech
18 whose original wing spars had been stiffened with a similar-sized steel
reinforcing strap underneath. It makes an un-aerodynamic bulge in the lower
wing surface.
http://www.twinbeech.com/sparstrap.htm

"Other manufacturers kits resemble bridge trusses and can protrude more than
10 inched from the skin of the Beech. Not only is this unsightly but it is
enough to make an aerodynamicist sick. I heard one owner say that one good
thing about his bridge truss spar strap was that if he ever had to belly
land his Beech at least the props wouldn't hit the ground!"



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"Jim Wilkins" wrote in message ...

The problem is designing a tension-side joint that gives the full strength
of the channel without blocking the trolley.

-------------------------

Am I correct in assuming that thickening the outside of the channel flange
with a welded-on shim to restore the area lost to bolt holes and sizing the
joining plate to at least that same net cross-sectional area is enough?

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"Jim Wilkins" wrote in message ...


The problem is designing a tension-side joint that gives the full strength
of the channel without blocking the trolley.

-------------------------

Am I correct in assuming that thickening the outside of the channel flange
with a welded-on shim to restore the area lost to bolt holes and sizing the
joining plate to at least that same net cross-sectional area is enough?

-------------------------------

This is similar to a filler plate in a splice between beams of different
heights. Are filler plates ever welded to the smaller beam?

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This is a half section of my present gantry hoist track splice design. C is
the 4" channel, V the 3/8" thick central splice plate between the channels,
H the 3/8" thick horizontal splice plate under the tension flanges and A the
angle iron splice above the compression flanges.

My question is how to weld the inverted T joint between V and H. I think an
inside fillet weld will deform H upward and require grinding off the sharp
and square lower corners of the channel. Is a row of plug or slot welds in H
a reasonable alternative to avoid distortion and interference?

The 6" high vertical center plate V alone has nearly the same Ixx as the two
channels so I don't think welding it to H is essential but connecting them
should make the joint stiffer and one-man assembly easier. The angle A on
top bolts to V and C afterwards, and gives the central hanger shackle pin
more bearing area than V alone would.

VA
VA
VA
VAAAAAA
VCCCCCC
VC
VC
VC
VC
VC
VCCCCCC
HHHHHH

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Default gantry - channel sections

"Jim Wilkins" writes:

This is a half section of my present gantry hoist track splice
design. C is the 4" channel, V the 3/8" thick central splice plate
between the channels, H the 3/8" thick horizontal splice plate under
the tension flanges and A the angle iron splice above the compression
flanges.

My question is how to weld the inverted T joint between V and H. I
think an inside fillet weld will deform H upward and require grinding
off the sharp and square lower corners of the channel. Is a row of
plug or slot welds in H a reasonable alternative to avoid distortion
and interference?

The 6" high vertical center plate V alone has nearly the same Ixx as
the two channels so I don't think welding it to H is essential but
connecting them should make the joint stiffer and one-man assembly
easier. The angle A on top bolts to V and C afterwards, and gives the
central hanger shackle pin more bearing area than V alone would.

VA
VA
VA
VAAAAAA
VCCCCCC
VC
VC
VC
VC
VC
VCCCCCC
HHHHHH


Is what you aim for structurally necessary or helpful is a good first
question given the work involved...

OK - using your notation and adding W for weld


...
VC
VC
VCCCCCC
WHHHHHW

So you now have the "H" as two strips with the inner edge bevelled
about 30deg.
Set with a root gap at least equal to the middle "V" plate. Wider and
you "get" some of the "C" channel.
Weld-up. Left and right corners and if necessary middle run for first
layer, then fill.

If "H" is a tension "doubler", not otherwise part of the beam "Second
Moment of Area", then just fillets at the ends would do?
Maybe small fillets along sides, out to edges of the "C" (channel)
sections?
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"Richard Smith" wrote in message ...

"Jim Wilkins" writes:

This is a half section of my present gantry hoist track splice
design. C is the 4" channel, V the 3/8" thick central splice plate
between the channels, H the 3/8" thick horizontal splice plate under
the tension flanges and A the angle iron splice above the compression
flanges.

My question is how to weld the inverted T joint between V and H. I
think an inside fillet weld will deform H upward and require grinding
off the sharp and square lower corners of the channel. Is a row of
plug or slot welds in H a reasonable alternative to avoid distortion
and interference?

The 6" high vertical center plate V alone has nearly the same Ixx as
the two channels so I don't think welding it to H is essential but
connecting them should make the joint stiffer and one-man assembly
easier. The angle A on top bolts to V and C afterwards, and gives the
central hanger shackle pin more bearing area than V alone would.

VA
VA
VA
VAAAAAA
VCCCCCC
VC
VC
VC
VC
VC
VCCCCCC
HHHHHH


Is what you aim for structurally necessary or helpful is a good first
question given the work involved...

OK - using your notation and adding W for weld


...
VC
VC
VCCCCCC
WHHHHHW

So you now have the "H" as two strips with the inner edge bevelled
about 30deg.
Set with a root gap at least equal to the middle "V" plate. Wider and
you "get" some of the "C" channel.
Weld-up. Left and right corners and if necessary middle run for first
layer, then fill.

If "H" is a tension "doubler", not otherwise part of the beam "Second
Moment of Area", then just fillets at the ends would do?
Maybe small fillets along sides, out to edges of the "C" (channel)
sections?

-------------------
I was expecting to do just that until I cleaned up the rusty channels and
found that the flanges are square to the web and a one-piece H plate fits
flush on both sides.

This with an abrasive fiber pad stripped the rust remarkably fast and
effectively and was easier to control than a 7" angle grinder.
https://www.harborfreight.com/air-an...der-93629.html

The 100kg track and hoist assembly has to come apart for handling and
storage so the channels can't be welded to the splice.

If the angle between H and V initially matches the outsides of the channel,
would it increase or decrease after filling the gap?

If the angle opens a little the channel would still bear solidly on H at the
root which may be acceptable. If the angle closes the channel will contact H
at the outer edge and shift under load. I don't have a press large enough to
bend 3/8" plate.

I considered plug welds assuming I could fill a 3/8" hole in one pass and
the weld would shrink symmetrically as it cooled, and the surrounding solid
metal would minimize distortion.

The plates and channels would be clamped together with a gap between the
channels under the weld. I could stop drilling and filling if the plates
began to warp out of alignment.



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Default gantry - channel sections

"Richard Smith" wrote in message ...

....
If "H" is a tension "doubler", not otherwise part of the beam "Second
Moment of Area", then just fillets at the ends would do?
Maybe small fillets along sides, out to edges of the "C" (channel)
sections?
----------------------
As a separate element H is only a little stronger than the lower channel
flange, because it has slightly more area and is further from the neutral
axis, but as part of V it more than doubles the second moment. I think shear
causes the difference.

I couldn't accurately measure these channels until a few days ago when I
sawed off the end plates (they were pallet rack shelves) and removed the
rust.

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Default gantry - channel sections

"Jim Wilkins" wrote in message ...

These are direct links to photos of my sawmill and overhead gantry track in
operation. Can you view them without having and being signed into a Google
account?
https://photos.google.com/photo/AF1Q...lXp0ArseMmj0d9

https://photos.google.com/photo/AF1Q...XvFBgR_fGKnyBH

The hoist, rope sling and pulley make manual log handling easy. I like it
better than the hydraulic log turner on a $40,000 WoodMizer. A cant hook /
Peavey turns large rough logs without getting too close, and a pipe clamp is
a good handle to turn a partly squared log without damage.


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Default gantry - channel sections

"Jim Wilkins" wrote in message ...

"Jim Wilkins" wrote in message ...

These are direct links to photos of my sawmill and overhead gantry track in
operation. Can you view them without having and being signed into a Google
account?
https://photos.google.com/photo/AF1Q...lXp0ArseMmj0d9

https://photos.google.com/photo/AF1Q...XvFBgR_fGKnyBH

The hoist, rope sling and pulley make manual log handling easy. I like it
better than the hydraulic log turner on a $40,000 WoodMizer. A cant hook /
Peavey turns large rough logs without getting too close, and a pipe clamp is
a good handle to turn a partly squared log without damage.



Google says:

404. Thats an error.

The requested URL was not found on this server. Thats all we know.

Best Regards.
Tom.

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