filling a pipe to make it act like sold shaft?

[BHD]

I have need of a slip roller at least 50" wide, and would like to be able to do 10 gauge, and would like to use it for rolling rings out of flat as well, at the ends, of the machine,

I have looked online and most start in at $800 and up fast, and there only rated for 16 gauge,

first if I would order in steel shafting of 4" I am reasonable sure my costs would start to rival a bought unit,

so the thought I have is to use heavy wall pipe (thinking 4" in diameter or near that), and a 1.5 shaft (or near that) running from end to end, with filler rings on the ends, to support the pipe, (hoping I can find some type of drill stem some where).

HERE IS THE QUESITON, is there any filler material I could pour in the center of the pipe to make it solid that would not disintegrate to dust in time, (like concrete) the idea is to make the pipe work like solid shaft,
any type of epoxy type filler that would be affordable?

the rollers will flex some on heaver gauges,

 

[Gary Fowler]

I would just go with 4" pipe in a heavy wall thickness like schedule 80 or even 120. That should not flex on a 50" length. Maybe also put in s support ring in the middle of the shaft also even though you cant weld it, it will keep the "axle" from flexing in the middle and therefore make it much more rigid.

 

[MechE1]

BHD. This brand is not really cost effective, but you could use the high durometer stuff. Hapflex 500 Series - HAPCO Inc. There are other brands that my be less expensive. Affordable and epoxy filler "castable" usually do not go together.

 

[grsthegreat]

man, when you start rolling thicker metals over 48" wide...your going to have a tough time with hand cranked slip roller. My Grizzly 50" roller has solid filled rollers and its still limited to 50" x 16 gauge steel. Mind you, if you were wanting to roll say 12" wide pieces, you can go alot thicker. These ratings are for full widths of steel.

Ive seen some 50" units that have electric, computer feeders, and there still rated 16 gauge

 

[RedNeckRacin]

I think your best bet would be a scrap yard. You never know what might turn up! Someone may be scrapping a dragline or a shovel and you could pick up the material you are looking for. If you want new material, some extra heavy walled pipe poured full of molten lead with caps welded on the end may do the trick???

Other than those options, a machine fitted collar to support the outside walls would be what makes sense to me.

 

[Creamer]

I would just go with 4" pipe in a heavy wall thickness like schedule 80 or even 120. That should not flex on a 50" length. Maybe also put in s support ring in the middle of the shaft also even though you cant weld it, it will keep the "axle" from flexing in the middle and therefore make it much more rigid.

This is good advice. Put a support ring or two in the middle and lock them into position some way axially along the shaft then a schedule 80 pipe. Any material you put in will not have the same stiffness and therefore you will have relative movement and it eventually will be useless. Stiffness is the key to this one - keeping the same material to have the same deflection under the load.

 

[Kenneth S]

Pipe no matter what you do is not going to do it, you need solid shaft. Most people don't know that slip roller shafts are ground with a slight taper (slightly bigger in diameter) in the middle of roller to compensate for roller flex. For rolling 10 gauge a minimum of 4" diameter solid shaft is as light as you can dare go for 50" wide (a machine that rolls 60" x 10 gauge uses 4 3/4" diameter solid shafts).

 

[Dozernut]

Maybe a rod out a large worn out hydraulic cylinder, some of those excavator cylinders have some big rods that might work. Maybe a hydraulic shop would have a junker they would sell you or maybe an old dozer setting in the brush.

 

[Egon]

Get a piece of drill stem or schedule 160 pipe and weld hubs onto the ends. The wall thickness will be enough so you don't have to worry about flex or dents.:thumbsup:

 

[BHD]

Thank you all for the ideas.

 

[npalen]

I'm not sure that adding an unwelded support out in the middle of the pipe would do any good. The smaller shaft thru the support would have only negligible effect to stiffness.

 

[CNC Dan]

I'm not sure that adding an unwelded support out in the middle of the pipe would do any good. The smaller shaft thru the support would have only negligible effect to stiffness.

Yep. The center will see the least stress, and contribute the least to stiffness. Go with the largest diameter you can, then use a wall thickness that will give the required stiffness.

 

[Gary Fowler]

I think my idea of a center axle rod running thru the middle with an inside do-nut tightly fit to the ID of the pipe would work just like a truss. The pipe couldn't bend or even flex without stretching the center rod. Welded on each end tightly with a thick plate that wouldn't bow in from the stress, I think it would even work with lighter wall piping.

 

[ishiboo]

Concrete/mortar is the way to go.

Epoxy would be very expensive, even using sawdust or whatever as filler, and it'd take a long time to fill as 2-part epoxy is exothermic, you'd have to put some in at a time and wait for it to cool. Filling the whole pipe at once would get HOT!

 

[npalen]

The "I" value of a beam determines it stiffness. The "I" (Moment of Inertia) of 4" schedule 160 pipe (4 1/2" OD x 0.531" wall thickness) is 13.25 where the "I" value of 1.5" diameter shaft is only 0.248 or less than 2% of the pipe. The shaft has very little effect even with the donut. I chose the 1.5" diameter shaft just because it would probably take at least 1.5" diameter bearings on the end to carry the load. The shaft does act like a truss but it just doesn't have the needed leverage or strength. The hardness of the steel doesn't have any effect on bending strength either unless it's bent past the yield point of the material.

 

[CNC Dan]

I think my idea of a center axle rod running thru the middle with an inside do-nut tightly fit to the ID of the pipe would work just like a truss. The pipe couldn't bend or even flex without stretching the center rod.

Nope. One side of the pipe will be in compression, the opposite side with in tension, and the center, neither. Look up the term "nutral axis".

 

[slowzuki]

Yup, the pipe is already a truss in a way. The center is mostly useless unless you are supporting the pipe from below with a wheel or similar point load and you need to prevent collapse of the pipe at the point.

 

[jenkinsph]

I recommend you cough up for the solid shaft, make sure you get the right alloy while you are at it. Might save a lot of cash if you can search a few industrial scrap piles.

 

[thorholt]

We used to use "Hard Block" water jacket filler on our drag race engines when we bored them out to the max, It is a concrete type product that you poured into the cooling passages of the block to strengthen the cylinder walls, It should work but I would think it might cost as much as a solid rod.
HardBlok Water Jacket Filler - Increase Horsepower For High Performance Engines.

 

[SPIKER]

While I can see what you are doing & can be done I would think the cost of a used industrial machine would be well under the build costs to make one that works WELL. That means that one that works for occasional rolling of something LIGHT once and a while then the drill pipe and rod would function. That is IF you have access to some old used sprockets to make the drive mech. as the fabrication of those would totally offset the cost of even a NEW import roller.

Using the plates welded to the thru rod that were turned to fit TIGHT to the HW pipe will help support it but others pointed out there is not a LOT of support there...

Mark