sheetmetal tapping 1

[Vikas4auto2019]

Hello Guys,

Can we make a thread (M5/M6) in 4 mm gal. sheetmetal?
If so, what should be the right pitch distance for this thickness?
and what abt reliability?


Thanks in Advance!!

 

[hendersdc]

You can tap sheet metal but you won't be getting very many threads. M5-0.8mm would get 5 and M6-1.0mm would get 4 assuming you don't deburr with a countersink and loose a little thickness. Any reason you can't use a threaded insert like a PEM nut or a rivnut? I would also suggest using thread forming taps instead of thread cutting taps in sheet metal.

The thread pitch you select (coarse vs fine) will depend on a lot of details about your application such as what is being mounted, what loads will it see, what type of fastener, etc.

[URL unfurl="true"]https://www.pemnet.com/fastening-products/pem-self-clinching-fasteners-new/[/url]
[URL unfurl="true"]https://www.rivetnutusa.com/rivnut-rivet-nut/[/url]

 

[mfgenggear]

@hendersdc is correct, some type of threaded insert

 

[MikeHalloran]

You can also get a few more usable threads by piercing and extruding the sheet into a little cylinder before using a forming tap.

The edge resulting from piercing the hole is usually rough and irregular (ugly), but the threads are strong enough for government work, in steel.

Mike Halloran
Corinth, NY, USA

 

[mfgenggear]

@Mike
That does work but will fail more easily and do become loose.

 

[RRiver]

You don't say anything about your application so specific advice is hard to give. I build cars for myself and others as a hobby-avocation now that I'm retired. A problem I often run in to is since or by the 70's a lot of the sheet metal fasteners were replaced with welds which isn't any good for something designed and built with a consideration for future work and disassembly. Unless space is an issue the small amount of space rivet nuts take up makes them a great option. If needed they can also be welded in place once they're located on the work piece..

https://www.amazon.com/s?k=rivnut+tool&ref=nb_sb_noss_1

 

[juergenwt]

M5 in 4mm should not give you a problem at all. C'sink lightly. If you have a extra heavy load - put a nut behind it.

 

[Vikas4auto2019]

Thank you guys for your quick response!!

I barely need 2 or 3 rotations of the screw.
The purpose is..I just need to clamp between Part A and B (required moment is 1mm max) .So part B will act somewhat like screw jack mechanism
I have already added thread insert but looking for a cheaper solution than this )

.

 

[handleman]

You could try flow drilling...

https://www.youtube.com/watch?v=VzCBQh8B_RY

Disclaimer: Haven't used it myself, but it looks nifty