Screw at MTX case bottom

[protek]

What type should the screw at the bottom of the MTX case, apparently securing the motherboard, be? I've been looking at the screw in mine and I'm not sure whether it's an original screw or not.

[Dave]

Look on the page .....
http://www.primrosebank.net/computers/mtx/mtxphoto.htm

Just below the video board photos, the bolt goes through the base and is fixed with a nut job n the heat sink tab. I'd need to check the size, but it's probably a small BA sized bolt.

I'll try and get measurements later

Regards
Dave

[protek]

I take you mean this one: http://www.primrosebank.net/computers/m ... emoved.jpg

Well it shows that the screw is anodized. Mine isn't. Is it supposed to be a countersink screw?

[Dave]

Hi, yes, that's the photo.

Just to be clear, the screw that you are talking about should "appear" through the hole in the 7805 regulator, it is not fitted in the photo, but this is the best photo that I have of the regulators and heat sink. They are usually obscured by C56.

No, it isn't normally a countersunk screw, it's a pan head bolt. Normally it is silver/steel coloured,

Regards
Dave

[protek]

Ok, then I think I have the correct screw in mine.

Thanks!

[1024MAK]

It has to be a M3 machine screw or an equivalent that has the same (or slightly smaller) diameter so that it fits the hole in the regulator. Mind, it is possible that you could use a slightly larger one, as the M3 machine screw and regulator are designed to have an insulating shaped washer fitted (not needed for the 7805 and 7812 regulators, the boost transistor does need insulating).

I don't know the length, as I have never bothered to measure it. When I needed to renew one (the existing one had become rather bent ) I selected a replacement of the correct length from my stock of spare machine screws.

The screw head can be either pan head or cheese head.

You will need a matching nut also.

Mark