Help with etch design

[NScaleNotes]

Hello

I've been using the guides on the Hollywood Foundry website to create an etch but I think I need a bit of help with folding. I'm trying to create an etch that will be folded up to create a rectangular section that will sit on top of a tube. I've attached what I've got so far.

The metal will be 0.15mm thick. The red areas represent the half-etches to guide the folds. Once folded the sections with the circular cutouts need to be 5mm wide and the rectangular sections need to be 6mm. I imagine folding towards yourself as you look at it but I don't think that matters. There is a tab and slot to help with fixing once folded-up.

If anyone has done etch folds successfully before, is this correct?

Thanks

Simon

[Chuffer Davies]

Hi Simon,

 

You've made one mistake.  The left most side including notch and fold should add up to the 5mm you require.  I make it that you are 0.05mm short on this side  i.e.the 4.65 should be 4.7mm.

 

Regards,

 

Frank  

[NScaleNotes]

Ah yes, thanks Frank.

I think that's because I got used to leaving a 0.05mm gap between interlocking parts from when I've been working in 3D printing. Suppose it's not necessary when you've got a consistently thick sheet of etch. I'll change that.

 

Simon

[Nig H]

Hi Simon,

 

Maybe I'm misunderstanding it but should the part on the right be 5.85mm long over the notch to get to 6mm total length?

 

Nigel Hunt

[NScaleNotes]

12 minutes ago, Nig H said:

Hi Simon,

 

Maybe I'm misunderstanding it but should the part on the right be 5.85mm long over the notch to get to 6mm total length?

 

Nigel Hunt

 

Hi Nigel

 

I see what you mean but I think it's a slight error in the way the measurements are presented in that image. In the file I'd send to be etched the central section of that part is 5.7mm and the tab above the notch is another 0.15mm plus the 0.15mm of the red half-fold.

 

Thanks

 

Simon

[DGO]

 I think if you want uniform corners that I'd put the join in one of the rectangular sides, otherwise you will find one corner looks different to the other 3, but thats just an opinion.

[NScaleNotes]

3 minutes ago, DGO said:

 I think if you want uniform corners that I'd put the join in one of the rectangular sides, otherwise you will find one corner looks different to the other 3, but thats just an opinion.

 

Now that's an idea, could have half-etched tabs to help connect it together too then.

Thanks.

[NScaleNotes]

 

So like this:

 

 

Red are half-etches one side, blue on the other. Now I hope this makes sense: I've made 'receiving' end half-etch (red) slightly longer than the 'tab' end half-etch (blue) because I know the etch liquid won't create a perfect right-angle in the corner of the 'receiving' half-etch.

 

I think this is called cusping. It should be no more than about 0.0225mm in 0.15mm sheet according to the guide.

But I suppose that also means I need to make the whole of the section with the red 'receiving' half-etch 0.05mm shorter to account for the cusp in the corner of the blue 'tab' half-etch. Should all line up nicely then... hopefully

Edited December 16, 2020 by NScaleNotes