Help - How to get a good edge to a metal box ?

[Jononon]

I'm making up a series of open metal boxes in 16ga mild steel, just bend and spot weld, to fit an existing set of drawers. No problems there, but it's become obvious that the top edges would be far better with a folded over hem.

Any thoughts as to the best way to get a good result, please ? I have use of a box and pan brake, and there's no real pressure for time, but I'd prefer not to spend much on tools/tooling to finish the job.

[russlaferrera]

What about a 1/4 in. band spot welded around the top of the drawer, on the inside?

[Franz©]

Decide how much lip you want to fold
Brake it as far as possible on the first fold
Declamp
Place folded lip under clamp and close
you may need to finish the close on an anvil or stake with a hammer

[Jononon]

Thanks chaps :)

you may need to finish the close on an anvil or stake with a hammer

:thumbup: I think that's the stage I'm missing. I can get it kind of OK-ish with the brake, but it leaves an open edge that isn't very neat.

I'd be the first to admit that you can write what I know about sheet metal work on the back of a postage stamp, so I'm starting small.

[Uncle Buck]

Thanks chaps :)



:thumbup: I think that's the stage I'm missing. I can get it kind of OK-ish with the brake, but it leaves an open edge that isn't very neat.

I'd be the first to admit that you can write what I know about sheet metal work on the back of a postage stamp, so I'm starting small.

That is how everyone begins a new skill; even the great ones! :thumbup:

[66 GMC Truckin]

I took a metal working course for bodywork, etc.. The instructor had us put a tig filler rod for the hem and hammer the edge of the panel over it. If you use a small gauge wire or filler rod and hammer the metal over the edge it will not go entirely flat, but will give you a really nice edge to your panel. Try some of these ideas on some scraps and see what you like the best. Scraps are cheaper than ruining a whole drawer. Good luck. Post some pics when you have it ready.

[Lu47Dan]

If you want a clean edge you need to fold the sheet metal over twice , I forget the name of it but it leaves a clean edge . the first bend needs to be slightly shorter that the second bend so it will lay flat against the side of the box . You also need to purchase a Hand seamer for flattening them out , home depot has them they are in the tool section with the tin snips . Also cut the corners at a 45 degree angle to make the corners more compact . Dan

[Quiksilver]

I know this wouldn't help with your metalworking experience, but for simplicity, what about just using a rubber edging around the top edge of the boxes?

[Jononon]

I took a metal working course for bodywork, etc.. The instructor had us put a tig filler rod for the hem and hammer the edge of the panel over it. If you use a small gauge wire or filler rod and hammer the metal over the edge it will not go entirely flat, but will give you a really nice edge to your panel.

I've been trying this. Gives a great edge, but it's soooo sloooow.

Presumably edges are formed industrially with a press ?

I know this wouldn't help with your metalworking experience, but for simplicity, what about just using a rubber edging around the top edge of the boxes?

That's my fall-back position, but I'd would like to give the edge a cleaner finish.

Thanks for all the advice, guys, pics will eventually follow :beer:

[danski0224]

I've been trying this. Gives a great edge, but it's soooo sloooow.

Presumably edges are formed industrially with a press ?



That's my fall-back position, but I'd would like to give the edge a cleaner finish.

Thanks for all the advice, guys, pics will eventually follow :beer:

Well, 16 ga is pretty thick material to be finishing off by hand.

A heavy duty enough brake (probably rated at 10ga) or something like a Roto-Die would make quick work of flattening things.

Production processes could even use a rollforming machine to make the edge you describe.

Another possible solution is bending some thinner stock, say 2" strips of 20ga, in half (180*) and placing this over your 16ga raw edge (1" on each side), then spot weld in place. This would give you a nice rounded edge without so much hand work on the thicker stock. Much easier to flatten into final position with hand tools, too. Going narrower, say 1/2" on each side, will be harder to work with.

[mulepackin]

I would slightly bevel the ends of the tabs you will be bending over. Then when the inside corners come together they aren't butting into each other. Makes a little neater appearance.

[gdf_77]

check out http://www.tricktools.com/sheet_metal_machines/bead_roller.htm

[Jononon]

Thanks again, guys. The rollers look an excellent way to finish the edge, but way too spendy for now.

Using the thinner stock, as danski0224 suggested, works very well, it's less of a strain than bending hems, but equally neat.

I was lucky enough to get a pallet of 20"x100" 16ga offcuts for free, but it really is too heavy for the job. When I get back into it in the new year (after I've finished providing my house with a functioning bathroom) I will get some pics up.

[bluesman2a]

wild idea here. forget folding it.
get some solid rod (somewhere 1/8 to 1/4"), Weld it to the top edge of the sheet.
Voila NICE uniform edge and stiffer than just the sheet itself.
If you really want to get tricky, just bend the corners in a vise for the best 90*.

[bobss396]

You want to do what is called a "dutch bend", aka a hem edge roll. I used to watch the old timers at work do them (real Dutchmen too), definitely not something for a beginner.

[Jononon]

Isn't a 'Dutch Bend' a tight double fold ? That would be great, but I'm not that ambitious !