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geekhack Projects => Making Stuff Together! => Topic started by: p3lim on Fri, 09 January 2015, 13:16:41

Title: Spacers and Poker case
Post by: p3lim on Fri, 09 January 2015, 13:16:41
So, I'm doing a hand-wired 60% using a plate, and mounting this in a Poker II case.
Since the case and screws were designed for screwing the PCB to the case, I need some spacers to make up for the distance.

What would be the spacer length I'd need, and what kind of (M2) screw length do I need?
Title: Re: Spacers and Poker case
Post by: jdcarpe on Fri, 09 January 2015, 14:25:38
It's 5mm from where the switch mounts to the plate (top) to the surface of the PCB. 1.5mm of that will be the metal plate (I'm assuming). And normally you would have a 1.5mm thick PCB on top of the standoffs. So 5mm spacers, right? And if your screw is going all the way through to the standoffs from the top of the plate, since you would normally use a M2-4mm screw, you need to add 5mm, giving you a 9mm long M2 screw.


Edit: Looks like you can get 8mm long or 10mm long screws. I would go with 10mm. You can always use small washers if you need.

http://www.mcmaster.com/#92005a033/=ve889k
Title: Re: Spacers and Poker case
Post by: p3lim on Fri, 09 January 2015, 15:17:00
You are my hero!

By the way, ordered the plate today ^_^
Title: Re: Spacers and Poker case
Post by: jdcarpe on Fri, 09 January 2015, 15:17:36
You are my hero!

Yes, that's true. I am. :P
Title: Re: Spacers and Poker case
Post by: Karura on Sun, 15 March 2015, 06:37:58
Just to tag along to this topic, since I'm also looking for replacement poker2 screws:

Which of the following screw material is preferred?

I see choices for Type 316 Stainless Steel, 18-8 Stainless Steel, and Zinc-plated Steel screws for the M2 sized screws.

I plan to use these screws with an aluminum Poker case, and was wondering if any of the materials will have an advantage over another, regardless of price?
Title: Spacers and Poker case
Post by: heedpantsnow on Sun, 15 March 2015, 07:48:45
Just to tag along to this topic, since I'm also looking for replacement poker2 screws:

Which of the following screw material is preferred?

I see choices for Type 316 Stainless Steel, 18-8 Stainless Steel, and Zinc-plated Steel screws for the M2 sized screws.

I plan to use these screws with an aluminum Poker case, and was wondering if any of the materials will have an advantage over another, regardless of price?

In metal on metal applications I prefer non-plated. Either of the stainless should work fine. Get whichever is cheaper.

Just be aware that stainless is non-magnetic usually so it will be harder to get down through plate as it won't stick to a magnetic screwdriver. This is why I prefer hex-head bolts for this; they stick well on the end of an Allen wrench to stick down through the plate.
Title: Re: Spacers and Poker case
Post by: p3lim on Sun, 15 March 2015, 12:35:10
Zinc-plated steel is more fragile than stainless steel in my experience, and also the availability of stainless steel screws is better.
I picked up a 10-pack of replacement 5mm M2 screws for a Toshiba laptop on Amazon for $2, worked just fine.
Title: Re: Spacers and Poker case
Post by: Karura on Mon, 16 March 2015, 19:58:51
Thanks for all the replies. I'm guessing none of these metals would have a corrosion problem when interacting with aluminium?
Title: Re: Spacers and Poker case
Post by: Karura on Mon, 16 March 2015, 20:16:05
Actually I just looked it up, looks like Zinc Plated is the best type of screws to use with aluminum.

Quote
Stainless Steel Screws
Stainless steel is an alloy of carbon steel that is, itself, resistant to corrosion. However, stainless steel is reactive with aluminum, and when a stainless steel screw is in contact with an aluminum base metal, the aluminum is likely to corrode. As is the case with carbon steel screws, a plated stainless steel screw is less likely to corrode aluminum; screws treated with a high-quality coating consisting of zinc and aluminum flakes are especially resistant to corrosion.



Read more : http://www.ehow.com/info_8135383_screws-compatible-aluminum.html

Source: http://www.ehow.com/info_8135383_screws-compatible-aluminum.html
Title: Re: Spacers and Poker case
Post by: p3lim on Mon, 16 March 2015, 20:20:50
Both the screws and plate in my keyboard are stainless steel, so that won't be an issue for me.