Sheet metal rolling tool

[gundamnitpete]

how exactly do these roll the steel? do you clamp the sheet under the tube, and use a hammer to beat it around into shape?

also, does this setup work better than a slip roll former?

and are there any plans out there for one of these?

[loco]

I've been having some trouble making decent tubes too, and I'm only using mild steel for my protoypes. I can get the basic shape so I can tack it into position, but then I get angular and flat sections which are so irritating when I've put so much care in cutting the templates out to be millimeter perfect.

Other than this home made slip roller, has anyone else had any luck with other methods of creating near perfect tubes?

I had an idea of using a set of barbells: tack the tube together, then place the bar of the barbells through the tube. Next, place the weights on the other end of the bar. You'd then need to rest the bar such that the weights aren't supported, so all the weight is on the bar which is pushing down on the tube you're rolling. You could then roll this whole contraption along: the weight and momentum of the barbells hopefully flattening out the kinks and making the tube smoother. What do you think?

[larry cottrill]

I had an idea of using a set of barbells: tack the tube together, then place the bar of the barbells through the tube. Next, place the weights on the other end of the bar. You'd then need to rest the bar such that the weights aren't supported, so all the weight is on the bar which is pushing down on the tube you're rolling. You could then roll this whole contraption along: the weight and momentum of the barbells hopefully flattening out the kinks and making the tube smoother. What do you think?

That sounds workable, IF you have a very flat slab (granite, concrete, steel work table) to support it. You would not want the weights to be excessive, because you want the bar to stay straight, not bowed up in the middle from the weights at the ends.

L Cottrill

[loco]

well I've just aquired a 1.5m length of scaffolding pipe, so I'll see what some time and a rubber mallet will do...

Cheers larry.

[Mark 42]

It shouldn't be too hard to build one of these:

http://www.harborfreight.com/cpi/ctaf/d ... mber=36698

[GRIM]

Here is my Cone Forming device

It is a variation on a type of sheet metal folding machine; it will not make beautiful smooth cones, like those used on some of the excellent creations on this forum

It will make accurate cones with many flat sides, see photos
And does require patience, practice (and accurate templates) to achieve good results

It is cheap, this one used scrap metal shafts, the only parts I purchased new, were the hex head bolts

The shafts should be the largest diameter possible, (the smallest diameter cone will be the factor here) and should be as short as possible, to resist flexing

I milled the grooves because I have access to a mill, they could be made with an angle grinder and patience

Might be of use to someone who has some junk lying around and doesn’t want to lay out cash for a slip roller

Thoughts criticism and opinions are welcome,
Are the many sided cones likely to affect the performance?
More / less harmonics?

I thank you in advance for your time, should you choose to reply

[Mike Everman]

Very beautiful. You clearly have learned to use it well.
No, it will not affect anything vs. smooth cones.

[El-Kablooey]

I really like the look of those cones. Nice job on the tool, and the cones!

[Mark]

I thought it was a nice presentation. With so many facets, it seems to approximate a cone shape very well. How many facets are there on the large cone? Maybe it will have some new characteristic or striped glow when hot.

[GRIM]

Hey, thanks to all for taking the time to reply,
There are 20 facets on all the cones both large and small, no particular reason for the number 20; I just hit the divide command until it looked about right.

When the time comes for the glowing part I will post a video,

Thanks to you tube, this forum and Larry Cottrill I now have a mistress in my life,
She cuts and burns my skin, steals my money, and makes my eyes and ears hurt , but I still cant leave her alone , I believe this is called an Obsession ,
But hell am I having fun!

[Jim Berquist]

Looks sort of sharp in its own way! I'm curious on how the facets are going to handle the heat!

Could a faceted cone weigh less then a cylindrical type? Less materials?


Jim

[GRIM]

The flat sheet development of the round cone and the faceted cone are identical, so will be equal in weight
I too am curious as to how she will look when hot , will keep you posted

[Eric]

A round cone will have less surface area and less weight.

That is pretty impressive, though you should be able to free form some pretty nice round cones with that setup there, just wear heavy work gloves and work it to shape, then pound with a mallet if you have to.

The facets look great, you will have a jewel of an engine when you are finished

Eric