my E-Wheel seems to work counter intuitivley

[woggon]

I just completed my e-wheel minutes ago (well, not quite finished, but enough to run a couple sheets of metal through it while clamped to the layout table).

When I run a sheet of metal through the wheels it bends in the opposite direction of the radiused wheel. That is to say if surface contact of the radiused wheel is rolls twards the floor at the edges, then the sheet metal bends twards the flat wheel. This goes against what I think I know. What gives? Did I do something wrong, or does the metal usually bend around the flat wheel. Too much pressure maybe?

Any insight would be appreciated.

Thanks,
Jay Woggon

[Boogiemanz1]

Woggon, are you rolling from end to end and starting on the edge?

Try starting in the center of the panel and rolling in a starburst pattern toward all the edges, but not off of them.....leave an inch or two that you don't wheel around the edges. This should raise a crown or slight dome. Use a sharpie to mark it off.

Also you may want to put a flat wheel on the bottom and roll it up to just touching the top. Look through the joining line at a light and see if the wheels are parallell.

There a probably 100 better recommendations coming , but this is a place to start...............john

[Wray Schelin]

I just completed my e-wheel minutes ago (well, not quite finished, but enough to run a couple sheets of metal through it while clamped to the layout table).

When I run a sheet of metal through the wheels it bends in the opposite direction of the radiused wheel. That is to say if surface contact of the radiused wheel is rolls twards the floor at the edges, then the sheet metal bends twards the flat wheel. This goes against what I think I know. What gives? Did I do something wrong, or does the metal usually bend around the flat wheel. Too much pressure maybe?

Any insight would be appreciated.

Thanks,
Jay Woggon

Hi Jay ,

Can you send in some pictures( several from different angles) of your sample ( what type of metal and thickness/) and your new e-wheel? That will help to see what you are doing . I suspect you are doing everything correct but you're not interpreting the results correctly. :D

Wray

[woggon]

I'm using 1/8" Al (don't know alloy or temper, but I haven't annealed), and 14 ga aluminum... again don't know alloy... purchased at a local scrap yard. I'm using a 2" radiused wheel and a flat upper wheel, both from Hoosier Pattern. I'm at my shop, and I don't have a camera here, but I will post pictures when I can.

I did start in the middle, in a starburst pattern.

It would just seem to me that the edges of the sheet should move twards the radiused wheel, or more correctly stated the streached area should be moving away from the radiused wheel (sort of). Instead the streached area is moving twards the radiused wheel. Not that I don't like the results! I just don't know that I can get a very tight radius this way.

Stated another way:
The area of metal that is worked I will describe as convex, which faces the 2" radiused wheel (The sheet started dead flat, and was only worked on one side).

I will post pics. to clairify.

-Jay

[Wray Schelin]

Hi Jay,

A lower anvil is an omni directional stretching tool. It compresses the metal only on it's working face called the contact area. As it compresses the metal it causes an area change. In other words the surface area of the metal grows wherever you wheel with enough pressure to cause stretching. Don't get hung up on the radius of the lower wheel or any sheetmetal shaping tool. That should be called the relief not the radius but that is another story. :shock: Improper labeling of tools and process in this craft causes more confusion. :roll: The relief or edge relief on a lower anvil or again any sheetmetal shaping tool create the open space for the metal to transform. If that relief space was not there the metal would be captured. The relief does not cause anything to happen, it allows the contact area's work a place to go.

To properly see what you have done to a panel you place it on a flat bench and have all of it's perimeter touch the bench. You should see shape or area change where you wheeled.

AREA change is what sheetmetal shaping is all about !!!

The other element that coexists with any panel besides AREA that is often referred to as Form or I prefer the more accurate name Arrangement How you arrange ( twist , roll, or bend) that panel which you added the Area to will determine what the finished panel looks like.

Wray

[woggon]

I think I understand now! :D After reading Wray's post a couple times, and then finishing the E-wheel frame, and then re-working the material I now understand. I was thinking of the wheel contacts as a ball peen hamer, or maybe even a cross peen. I was thinking the material was streching in the wrong direction. I needed to think of the wheel as a cross peen hammer.

Thank You.
-Jay Woggon

[Ron W]

I once tried some 11 ga. in my English wheel and it went the wrong way. The smaller wheel on the bottom streched the metel on the underside of the panel (not all the way through) more than the top of the panel. That made the metel move the opposite way of a thinner sheet. Had me guessing for a while.
Regards
Ron