Pyramid rolls fabrication and operation

[tylerae40]

I'm looking to make a set of pyramid rolls For home out of scrap. I have three rollers. My question is if I only drive the top roller , will it still work?
Normaly the top roller goes up and down, and the bottom two drive.

 

[Jagmandave]

What is this exactly? And what do you use it for?

 

[Kevin54]

I'm looking to make a set of pyramid rolls For home out of scrap. I have three rollers. My question is if I only drive the top roller , will it still work?
Normaly the top roller goes up and down, and the bottom two drive.

What is this exactly? And what do you use it for?

Jagman......It is a roller to roll sheetmetal. Two rollers at the bottom and one roller at the top in between the two that is adjustable. Looking at it from the end the three rollers form a triangle

Tyler....all you can do is try it to see what happens. My guess is that it will slip quite a bit. Normally you want the stationary rollers to be your drive rollers.

 

[lametec]

More commonly known as a slip roll, I'd think.

 

[Kevin54]

More commonly known as a slip roll, I'd think.

Most "slip rolls" I have saw usually have 2 rollers instead of 3. I could be wrong as I have been known to be on numerous occasions. But in a nutshell, whether 2 or 3 rollers, it's used to roll sheetmetal.

 

[lametec]

How would a 2-roller slip roll work?

 

[gorilla]

I believe the other type of forming roll is called an upset roll. Why would you want to power the top roll? It needs to be adjustable to achieve the bend you want and one end needs to hinge open to remove the work piece.

 

[Kevin54]

How would a 2-roller slip roll work?

One is directly above the other and the more you tighten the roll down, by some molecular change that I don't understand, will curl the material. Same thing as when you take a pair of scissors and run a piece of ribbon through them to get the ribbon to curl. Same with a piece of paper. It will stretch or shrink one side of the material.

Without knowing the correct terminology, metal can be read to know what it will do if you work with it enough. For instance, in machining a piece of 3" wide, 6" long, 1/2" thick piece of aluminum using a fly cutter, and you want to cut it down to 7/16" thick. You clamp the piece of aluminum in your mill vise and start cutting it down on one side only, removing .062, that piece of material will curl up by maybe .010-.020 depending on the type of aluminum, when you check it on a surface plate.

If you would have another piece of the same material, and you start cutting it with a fly cutter and you take .031 off of each side, that material may be out by .001-.002 when checked on a surface plate.

Cutting the aluminum will change the molecules and pull them closer together on the side that you are cutting causing the material to bow. When you cut both sides, it does the same thing to each side and you reach a happy medium.

 

[tylerae40]

The top roller is the one that moves up and down putting pressure on the metal making it bend and the bottom two are normally stationary and are driven, meaning they push the metal through creating a constant curve. They are used to make curved metal handrails, roll up pipe work etc etc. the ones I am making are to put curves in flatbar to layout patters for designs and for making curved hand rails.

 

[K13]

So are you thinking more of a ring roller then if you are using flat bar? Slip rolls are more for sheet metal, have a 16 gauge max capacity and usually all three rollers are driven. Ring rollers are more designed for flatbar type applications and usually just the top roller is driven.

Slip roll:
http://www.trick-tools.com/JET_SR_1650N_50_inch_Slip_Roll_16_gauge_756050_1084#.UgrZYRP4Cpo

Ring Roller:

http://shopoutfitters.com/338-pedestal-ring-roller/

Never heard of a two roll slip roll not sure how that would work as all it would do is thin the metal (this is how they make sheet steel) you require the metal to be pushed down into the space between the two other rollers to create shape. The only two roll metal working tools I can think of are an English wheel and a bead roller.

 

[OccupantRJ]

I have never seen a two roll metal roller either, but I bet it could be done by having 2 rollers of different diameters, as the contact points for each side would be a different aspect, as seen by the metal. This should cause the metal to curve slightly. That's my brain storm for today.

 

[tylerae40]

Cheers K13, and everyone else. Yes what i am making is a set of ring rollers, I've done a through google search and I've found that most of the light duty (hand driven) rollers are driven by only one roller- the rest are driven by two rollers- either through gears or by chain.
Also on a side note with the project i scored another four rollers today, and found out their proper use. So i may be making another ring roller in the future that is twice as wide.
the rollers are the wheels on the bottom of the electric forklifts- so their rated to a few tones of pressure and a happy to roll along with that weight. the rollers are normally coated in rubber or plastic so as to give it a soft grip to the floor, but i'll just strip that off. i will post pics as it comes along. cheers

 

[lametec]

One is directly above the other and the more you tighten the roll down, by some molecular change that I don't understand, will curl the material.

Same way an English wheel works. But to use that on a wide sheet to curve the whole thing would take some serious tonnage and rigidity. Way beyond what someone would typically build at home!

Not saying it can't be done, but I've never heard of it.

 

[motobilt]

My slip roll and every other one I have seen has three rollers. I don't recall seeing one with only two. The mechanical force to roll a piece of sheet metal with 2 rollers would be high. I would like to see one work. Even the large hydraulic rollers are three roll. IDK... maybe I just have not been paying attention.

-Dan

 

[tylerae40]

If it has two small rollers it'd be an English wheel, used to put curves both ways in sheet metal , like making an old car fender or pannel. The rollers on these have curves both ways in different sizes depending on what you are doing.
The rollers which are for rolling up sheet metal in one direction only across a length are star standard rollers in the pyrimid and pinch patten they both have three rollers it just depend on which roller goes up and down.
Ring rollers are for rolling bar stock, flat bar or pipe into rings. These have three short rollers.
They also have different dies for different shape material.

 

[theknurl]

we have terminology confusion here

Pyramid rolls are used to manufacture sheet metal, the rollers touching the roller are under extreme pressure, so they back that roller with 2 more.....and those 2 with 4 thus making a Pyramid

slip rolls are used to form sheet metal...
the 2 "pinching" rollers are GEARED together not chained, they must turn opposite directions
the lower one is the 1 that moves;
http://www.roperwhitney.com/pexto-slip-rolls.html

the 3rd roller is never driven.....because it won't "slip" and make cones

the 6" long 2 roll machines are usually for gold and silver smiths.....

or making pasta