https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for about
half local metal yard retail. I'm going to use one piece as the top for
my welding table until I run across a good deal on something thicker. I
decided to buy some extra just because the price was good enough to be
worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I have
pulled my 12 ton partially apart. I can still use it, but only above
the torn metal. LOL. My 20 ton now has a bow on the top beam. That's
what happens when you try to press a prop hub out in the wrong direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as tall as
stretch built his in the video. I won't have a joint in the pieces like
he does, and I wasn't planning on going 50 ton. I've got a pretty beefy
30 ton cylinder and power unit off of a log splitter I was thinking
about using for the hydraulic part. My 20 ton has been adequate for
anything I needed to press except for the fact that I managed to bend
it. I've also got some heavier stock for things like the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my own
upright tube is.

"Bob La Londe" wrote in message
news
https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for
about half local metal yard retail. I'm going to use one piece as
the top for my welding table until I run across a good deal on
something thicker. I decided to buy some extra just because the
price was good enough to be worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I have
pulled my 12 ton partially apart. I can still use it, but only
above the torn metal. LOL. My 20 ton now has a bow on the top
beam. That's what happens when you try to press a prop hub out in
the wrong direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as tall
as stretch built his in the video. I won't have a joint in the
pieces like he does, and I wasn't planning on going 50 ton. I've
got a pretty beefy 30 ton cylinder and power unit off of a log
splitter I was thinking about using for the hydraulic part. My 20
ton has been adequate for anything I needed to press except for the
fact that I managed to bend it. I've also got some heavier stock
for things like the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my own
upright tube is.

If you can match the frame members to this table you can calculate the
tension and bending stresses, then give your modifications a larger
margin.
https://www.engineersedge.com/standa...properties.htm

-jsw

Bob La Londe writes:

https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for about
half local metal yard retail. I'm going to use one piece as the top
for my welding table until I run across a good deal on something
thicker. I decided to buy some extra just because the price was good
enough to be worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I have
pulled my 12 ton partially apart. I can still use it, but only above
the torn metal. LOL. My 20 ton now has a bow on the top beam.
That's what happens when you try to press a prop hub out in the wrong
direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as tall
as stretch built his in the video. I won't have a joint in the pieces
like he does, and I wasn't planning on going 50 ton. I've got a
pretty beefy 30 ton cylinder and power unit off of a log splitter I
was thinking about using for the hydraulic part. My 20 ton has been
adequate for anything I needed to press except for the fact that I
managed to bend it. I've also got some heavier stock for things like
the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my own
upright tube is.

The frame "uprights" of a press (hydraulic press) are in pure tension.
Very rare engineering loading case. Abnormally easy to treat.
Opposite of instability - the load "assists" pulling them straight.
Load bearing in this very special case is totally simply to calculate
on-paper:
multiply the cross-sectional-area (width*thickness)
by the
yield stress divided a safety-factor (say 5?)
and there you have it.

Typical other cases:
In a beam you have to consider buckling instability, etc.
Likewise a column (it looks the same as a "tie" but is in
compression).
The engineering design is much more complex and you have to work out
which effect comes to the fore in most limiting the load-bearing
capacity.

Hope this is helpful comment...
Regards,
Rich S

"Richard Smith" wrote in message
...
Bob La Londe writes:

https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for
about
half local metal yard retail. I'm going to use one piece as the
top
for my welding table until I run across a good deal on something
thicker. I decided to buy some extra just because the price was
good
enough to be worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I have
pulled my 12 ton partially apart. I can still use it, but only
above
the torn metal. LOL. My 20 ton now has a bow on the top beam.
That's what happens when you try to press a prop hub out in the
wrong
direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as
tall
as stretch built his in the video. I won't have a joint in the
pieces
like he does, and I wasn't planning on going 50 ton. I've got a
pretty beefy 30 ton cylinder and power unit off of a log splitter I
was thinking about using for the hydraulic part. My 20 ton has
been
adequate for anything I needed to press except for the fact that I
managed to bend it. I've also got some heavier stock for things
like
the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my
own
upright tube is.

The frame "uprights" of a press (hydraulic press) are in pure
tension.
Very rare engineering loading case. Abnormally easy to treat.
Opposite of instability - the load "assists" pulling them straight.
Load bearing in this very special case is totally simply to
calculate
on-paper:
multiply the cross-sectional-area (width*thickness)
by the
yield stress divided a safety-factor (say 5?)
and there you have it.

Typical other cases:
In a beam you have to consider buckling instability, etc.
Likewise a column (it looks the same as a "tie" but is in
compression).
The engineering design is much more complex and you have to work out
which effect comes to the fore in most limiting the load-bearing
capacity.

Hope this is helpful comment...
Regards,
Rich S

What he wrote is true only if the connections to the horizontal
members that withstand the pressing force are somewhat free to rotate
at their ends as they deflect, ie they are bolted along the centerline
of the uprights instead of being welded.

A bolted or pinned joint with some give leaves the tension evenly
distributed across the uprights, while a solid welded joint
concentrates the stress on the inner corner as the top crosspiece
flexes upward.. Look closely at the design of commercial presses.
-jsw

"Jim Wilkins" wrote in message news
"Richard Smith" wrote in message
...
Bob La Londe writes:

https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for about
half local metal yard retail. I'm going to use one piece as the top
for my welding table until I run across a good deal on something
thicker. I decided to buy some extra just because the price was good
enough to be worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I have
pulled my 12 ton partially apart. I can still use it, but only above
the torn metal. LOL. My 20 ton now has a bow on the top beam.
That's what happens when you try to press a prop hub out in the wrong
direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as tall
as stretch built his in the video. I won't have a joint in the pieces
like he does, and I wasn't planning on going 50 ton. I've got a
pretty beefy 30 ton cylinder and power unit off of a log splitter I
was thinking about using for the hydraulic part. My 20 ton has been
adequate for anything I needed to press except for the fact that I
managed to bend it. I've also got some heavier stock for things like
the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my own
upright tube is.

The frame "uprights" of a press (hydraulic press) are in pure tension.
Very rare engineering loading case. Abnormally easy to treat.
Opposite of instability - the load "assists" pulling them straight.
Load bearing in this very special case is totally simply to calculate
on-paper:
multiply the cross-sectional-area (width*thickness)
by the
yield stress divided a safety-factor (say 5?)
and there you have it.

Typical other cases:
In a beam you have to consider buckling instability, etc.
Likewise a column (it looks the same as a "tie" but is in
compression).
The engineering design is much more complex and you have to work out
which effect comes to the fore in most limiting the load-bearing
capacity.

Hope this is helpful comment...
Regards,
Rich S

What he wrote is true only if the connections to the horizontal
members that withstand the pressing force are somewhat free to rotate
at their ends as they deflect, ie they are bolted along the centerline
of the uprights instead of being welded.

A bolted or pinned joint with some give leaves the tension evenly
distributed across the uprights, while a solid welded joint
concentrates the stress on the inner corner as the top crosspiece
flexes upward.. Look closely at the design of commercial presses.
-jsw
***************

Thanks. Being a boat fan (welded and molded) I am somewhat familiar with
the stresses at what we call hard points. I have experienced various
degrees of failure at hard points from broken welds in aluminum to stress
fractures in gel coat even in name brand commercial products. Its good to
think about this in a different application. I'd note that I've also seem
failures on two hydraulic presses. Neither was instant or catastrophic.
Both were Harbor Freight presses. The column on a 12 ton literally pulled
apart with a 12 ton jack, and the top beam bent on a 20 ton using a 20 ton
jack. They are both still moderately useable. I had certainly intended to
study their modes of failure as I approach the new build.

"Bob La Londe" wrote in message news
"Jim Wilkins" wrote in message news
"Richard Smith" wrote in message
...
Bob La Londe writes:

https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for about
half local metal yard retail. I'm going to use one piece as the top
for my welding table until I run across a good deal on something
thicker. I decided to buy some extra just because the price was good
enough to be worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I have
pulled my 12 ton partially apart. I can still use it, but only above
the torn metal. LOL. My 20 ton now has a bow on the top beam.
That's what happens when you try to press a prop hub out in the wrong
direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as tall
as stretch built his in the video. I won't have a joint in the pieces
like he does, and I wasn't planning on going 50 ton. I've got a
pretty beefy 30 ton cylinder and power unit off of a log splitter I
was thinking about using for the hydraulic part. My 20 ton has been
adequate for anything I needed to press except for the fact that I
managed to bend it. I've also got some heavier stock for things like
the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my own
upright tube is.

The frame "uprights" of a press (hydraulic press) are in pure tension.
Very rare engineering loading case. Abnormally easy to treat.
Opposite of instability - the load "assists" pulling them straight.
Load bearing in this very special case is totally simply to calculate
on-paper:
multiply the cross-sectional-area (width*thickness)
by the
yield stress divided a safety-factor (say 5?)
and there you have it.

Typical other cases:
In a beam you have to consider buckling instability, etc.
Likewise a column (it looks the same as a "tie" but is in
compression).
The engineering design is much more complex and you have to work out
which effect comes to the fore in most limiting the load-bearing
capacity.

Hope this is helpful comment...
Regards,
Rich S

What he wrote is true only if the connections to the horizontal
members that withstand the pressing force are somewhat free to rotate
at their ends as they deflect, ie they are bolted along the centerline
of the uprights instead of being welded.

A bolted or pinned joint with some give leaves the tension evenly
distributed across the uprights, while a solid welded joint
concentrates the stress on the inner corner as the top crosspiece
flexes upward.. Look closely at the design of commercial presses.
-jsw
***************

Thanks. Being a boat fan (welded and molded) I am somewhat familiar with
the stresses at what we call hard points. I have experienced various
degrees of failure at hard points from broken welds in aluminum to stress
fractures in gel coat even in name brand commercial products. Its good to
think about this in a different application. I'd note that I've also seem
failures on two hydraulic presses. Neither was instant or catastrophic.
Both were Harbor Freight presses. The column on a 12 ton literally pulled
apart with a 12 ton jack, and the top beam bent on a 20 ton using a 20 ton
jack. They are both still moderately useable. I had certainly intended to
study their modes of failure as I approach the new build.
****************

Hmmmmm.... looks like if I use 1" pins and holes closely sized I'd get some
minor hole deformation at high tonnage the first time I used a particular
set of holes, but be below the yield strength on those holes afterwards
(full engagement of pins after first deformation.) If I used larger pins
the upto under 50% of the column width my strength just goes up. As to the
column itself I'd be an order of magnitude below what a 30 ton ram could
dish out. After that its a matter or making sure the table and top beam
are good for the stresses involved. I have time to think about this though.
Its not tomorrows project. I'm still finishing up my welding table.

"Bob La Londe" wrote in message
news
"Bob La Londe" wrote in message news
"Jim Wilkins" wrote in message news
"Richard Smith" wrote in message
...
Bob La Londe writes:

https://www.youtube.com/watch?time_c...&v=f2xlAWytx9g

I know some folks may not be a fan, but I noticed he made his main
uprights out of 1/4" steel plate welded up into a box.

I just made a deal on a small quantity of 4x8x1/4 A36 plate for
about
half local metal yard retail. I'm going to use one piece as the
top
for my welding table until I run across a good deal on something
thicker. I decided to buy some extra just because the price was
good
enough to be worth sitting on it for a while.

I've been want a little better hydraulic press for a while. I
have
pulled my 12 ton partially apart. I can still use it, but only
above
the torn metal. LOL. My 20 ton now has a bow on the top beam.
That's what happens when you try to press a prop hub out in the
wrong
direction.

Anyway, I was wondering if 1/4 plate really was adequate for the
uprights on something like that. I have no need to make one as
tall
as stretch built his in the video. I won't have a joint in the
pieces
like he does, and I wasn't planning on going 50 ton. I've got a
pretty beefy 30 ton cylinder and power unit off of a log splitter
I
was thinking about using for the hydraulic part. My 20 ton has
been
adequate for anything I needed to press except for the fact that I
managed to bend it. I've also got some heavier stock for things
like
the top and table.

Ok, tell me how stupid the idea of using 1/4 plate and making my
own
upright tube is.

The frame "uprights" of a press (hydraulic press) are in pure
tension.
Very rare engineering loading case. Abnormally easy to treat.
Opposite of instability - the load "assists" pulling them straight.
Load bearing in this very special case is totally simply to
calculate
on-paper:
multiply the cross-sectional-area (width*thickness)
by the
yield stress divided a safety-factor (say 5?)
and there you have it.

Typical other cases:
In a beam you have to consider buckling instability, etc.
Likewise a column (it looks the same as a "tie" but is in
compression).
The engineering design is much more complex and you have to work
out
which effect comes to the fore in most limiting the load-bearing
capacity.

Hope this is helpful comment...
Regards,
Rich S

What he wrote is true only if the connections to the horizontal
members that withstand the pressing force are somewhat free to
rotate
at their ends as they deflect, ie they are bolted along the
centerline
of the uprights instead of being welded.

A bolted or pinned joint with some give leaves the tension evenly
distributed across the uprights, while a solid welded joint
concentrates the stress on the inner corner as the top crosspiece
flexes upward.. Look closely at the design of commercial presses.
-jsw
***************

Thanks. Being a boat fan (welded and molded) I am somewhat familiar
with
the stresses at what we call hard points. I have experienced
various
degrees of failure at hard points from broken welds in aluminum to
stress
fractures in gel coat even in name brand commercial products. Its
good to
think about this in a different application. I'd note that I've
also seem
failures on two hydraulic presses. Neither was instant or
catastrophic.
Both were Harbor Freight presses. The column on a 12 ton literally
pulled
apart with a 12 ton jack, and the top beam bent on a 20 ton using a
20 ton
jack. They are both still moderately useable. I had certainly
intended to
study their modes of failure as I approach the new build.
****************

Hmmmmm.... looks like if I use 1" pins and holes closely sized I'd
get some minor hole deformation at high tonnage the first time I
used a particular set of holes, but be below the yield strength on
those holes afterwards (full engagement of pins after first
deformation.) If I used larger pins the upto under 50% of the
column width my strength just goes up. As to the column itself I'd
be an order of magnitude below what a 30 ton ram could dish out.
After that it's a matter or making sure the table and top beam are
good for the stresses involved. I have time to think about this
though. Its not tomorrows project. I'm still finishing up my
welding table.

https://www.egr.msu.edu/~harichan/cl...e405/chap5.pdf

You can increase the bearing strength of the column holes by welding
on doubler plates.

I have a similar bolt strength problem to solve for the splice
plate(s) joining 8' channels into the the 16' track of a gantry
hoist.
-jsw

On Saturday, September 1, 2018 at 11:12:10 AM UTC-7, Bob La Londe wrote:

Hmmmmm.... looks like if I use 1" pins and holes closely sized I'd get some
minor hole deformation at high tonnage the first time I used a particular
set of holes, but be below the yield strength on those holes afterwards
(full engagement of pins after first deformation.)

If instead of pins, you used structural tube, the tube (though having high yield
strength) could elastically deform to the holes, which would minimize their
yield (because of high contact area). Our old (?75) ton press used
tube for the height-adjust pins.

Some tubes have sliding fit inserts of smaller tubes and making up two
or three
tubes inside makes for a strong tube looking device. Often times layers
are
stronger than solid.

Martin

On 9/2/2018 3:32 AM, whit3rd wrote:
On Saturday, September 1, 2018 at 11:12:10 AM UTC-7, Bob La Londe wrote:

Hmmmmm.... looks like if I use 1" pins and holes closely sized I'd get some
minor hole deformation at high tonnage the first time I used a particular
set of holes, but be below the yield strength on those holes afterwards
(full engagement of pins after first deformation.)

If instead of pins, you used structural tube, the tube (though having high yield
strength) could elastically deform to the holes, which would minimize their
yield (because of high contact area). Our old (?75) ton press used
tube for the height-adjust pins.

"Martin Eastburn" wrote in message
...
Some tubes have sliding fit inserts of smaller tubes and making up
two or three
tubes inside makes for a strong tube looking device. Often times
layers are
stronger than solid.

Martin


https://www.aero-mag.com/read-all-about-it/
"Of particular interest is the unusual construction of the Spitfire's
main wing spar booms. Each spar boom is built up from five
square-section concentric tubes made of 11 SWG aluminium alloy and one
square section central plug. The tubes are made to fine tolerances and
fit tightly into each other. Using specially commissioned photographs
and original working drawings we show how at the wing root the spar
booms are made up of five thicknesses of tube, but as the loads on the
spar decrease progressively towards the wing tip, so the inner tubes
terminate one by one, until at the wing tip only the two outer
thicknesses of tube remain."

I have the book. It's a good effort but this is its weakness:
"Scope for an in-depth technical manual is necessarily restricted by
our self-imposed limit to 160 pages "