M3? self tapping screws

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ruffrecords

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Is it possible for a self tapping screw to work in aluminium? I have an extrusion which has 3mm diameter holes in it and I want to attach a screening panel to it. At this point the extrusion is 2mm thick.

Cheers

ian
 

MidnightArrakis

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Is it possible for a self tapping screw to work in aluminium? I have an extrusion which has 3mm diameter holes in it and I want to attach a screening panel to it. At this point the extrusion is 2mm thick.

Cheers

ian
[Is it possible for a self tapping screw to work in aluminium?] -- If the aluminum is 5052, it -- should -- be soft enough to accept a self-tapping screw. However, 6061 aluminum would be another story.

If you have a piece of scrap aluminum laying around, give it a try!!!

I am assuming that you have read my latest response???

JBW

/
 

JohnRoberts

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In my first generation drum tuner package I tooled up an aluminum extrusion. I used thread cutting screws lengthwise screwed into bosses tooled into the extrusion.

For thin aluminum plates maybe try sheet metal screws.. Try different screws to find what works.

JR
 

ruffrecords

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[Is it possible for a self tapping screw to work in aluminium?] -- If the aluminum is 5052, it -- should -- be soft enough to accept a self-tapping screw. However, 6061 aluminum would be another story.

If you have a piece of scrap aluminum laying around, give it a try!!!

Will do. Just ordered some #6 self tappers
I am assuming that you have read my latest response???

Yes, still mulling that over ;)

Cheers

Ian
 

Newmarket

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I'd say it's probably okay. But I'd opt for tapping a thread for a machine screw. ime self tapping is good for only a few repetitions. Used tapped threads in die cast enclosures in a previous workplace.. Just seconds to do really. And that was without using a combined drill/tap as the boxes were drilled externally (because we had a large hole for a fan) then holes tapped by us as required.
 

Rob Flinn

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Have you tried thread forming screws instead of self tapping. They create a better thread. The reason being self tapping remove material & thread forming displace the material to make the thread. I got introduced to thread forming screws when I contracted for a design company. We used them in some aluminium extrusions & the thread was superior.
 

ruffrecords

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Have you tried thread forming screws instead of self tapping. They create a better thread. The reason being self tapping remove material & thread forming displace the material to make the thread. I got introduced to thread forming screws when I contracted for a design company. We used them in some aluminium extrusions & the thread was superior.
I came across them in my search but I have not tried them. Given the size of the existing holes I suspect I would need an M3.5 tap which does not seem to be available as a thread forming screw.

Cheers

Ian
 

MidnightArrakis

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I came across them in my search but I have not tried them. Given the size of the existing holes I suspect I would need an M3.5 tap which does not seem to be available as a thread forming screw.

Cheers

Ian
What is it that you are building, joining or attempting to do? Knowing that would certainly help a bit.

As shown below, I normally use "self-clinching" nuts that are installed by the sheet-metal shop. I only need to specify the "Model Number" of the nut and the shop takes care of the rest. But, -- WHAT -- it is that you are doing would help make a proper decision as to what to best use.

The images shown below are M3.5 "self-clinching" nuts:

1697184558391.png

>> Side-view showing "self-clinching" nut pressed into aluminum sheet-metal:
1697184465906.png

1697184704504.png

[Just ordered some #6 self tappers] -- As in a #6-32 machine screw?

>> The below images are of a #6-32 "self-clinching" nut. These
are what I usually use in my chassis/enclosure/housing designs:
1697185249920.png

/
 

Tubetec

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Self clinching types arent great on an aluminium panel , they have a tendency to fall out , its often used as a retaining screw to mount amps in cabinets , if the screw loosens and the amp takes a knock the clinch nut pops out ,
The riv-nut is much more sturdy . I never thought to look for them in smaller sizes , or made of brass .
 

ccaudle

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Ian said aluminum extrusion, so I expect something like this (circled area is where self-tapping screw would be used to hold a panel against the extrusion):

1697206467974.png
 

ruffrecords

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What is it that you are building, joining or attempting to do? Knowing that would certainly help a bit.
I am trying to attach a 1mm thick galvanised steel screen to the bottom of a mixer. Across the front and across the rear of the the bottom are aluminium extrusions as shown in the attached pdf. The entire width of the extrusion is pierced with ~3mm holes normally used to clip in plastic card guides. However the are no card guides on the two bottom extrusions so I thought to maybe use the existing holes to attach the screen. The holes are on 0.2 inch centres so there is not a lot of meat around them.

Cheers

Ian
 

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my 2 cents,, (to just hold a screen in place I'd hazard a guess that virtually anything would work, at 2m thick basically any sheet metal screw or self tapping screws. (both work in aluminum) if you want the threaded inserts (for a deeper and proper thread) you can use the 'Keystone' brand inserts and just cinch them with a vise (or even a hammer) no need for special installation tools, and they won't pull out like the pem nuts above.. i use the 6-32 inserts here every week , usually just closing them in a vice.-it's not even worth setting up the installation tool if i'm doing just a few..
 

jeffbro

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my 2 cents,, (to just hold a screen in place I'd hazard a guess that virtually anything would work, at 2m thick basically any sheet metal screw or self tapping screws. (both work in aluminum) if you want the threaded inserts (for a deeper and proper thread) you can use the 'Keystone' brand inserts and just cinch them with a vise (or even a hammer) no need for special installation tools, and they won't pull out like the pem nuts above.. i use the 6-32 inserts here every week , usually just closing them in a vice.-it's not even worth setting up the installation tool if i'm doing just a few..
Could you be a little more specific? When I search the Keystone website I don't see the clinched inserts you are describing.
 

zamproject

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Across the front and across the rear of the the bottom are aluminium extrusions
The side view of your technical drawing is not clear, with the arrow and axis lines for the tap screw masking the graphic, but this kind of eurorack extrusion usually have a longitudinal notches that is used to slide a top or bottom panel.

euro extrusion.png
 

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