Need M3.5x.6 flat head screw...

[10KPete]

I need one (1) lousy screw to complete an assy.  I've overhauled a Biax scraper. It was missing one screw when I got it and, of course, it's an odd size. It was common 30 years ago when the machine was new, but isn't now.

I can find these screws... in large quantities, from China, etc. But I need just one! I don't have a die (and don't want to pay $25 or more for one) and don't have metric gears for my lathe. And I don't want to make two new inserts for the plastic housing so it will take a more common screw. It always seems to come down to one lousy thing...

M3.5 x .6 x 6mm long (or longer) flat head slotted. Or Philips (2 ea.)

There are two of these screws that hold the back motor cover on and it takes two to keep the cover from twisting around.

If anyone has a screw, or knows where I can buy just a couple, I would appreciate hearing from you.

No, McMaster-Carr doesn't have them and Google hasn't  managed to find less than carload lots for me.

Thanks for your help,

Pete (very frustrated at the moment)

[crueby]

Is it in a place and material where you could drill and tap to a size you have taps for? Or fill the hole with jb weld and tap smaller, sounds like not a lot of force on it.

[Walsheng]

Is this it?  $2.30 for 100.

John

[Walsheng]

Sorry, the attachment was supposed to be a PDF.
The McMaster number is 91420A173.

John

[Nick_G]

.
That is a standard screw in the UK. - But thats not much use to you is it.

When I say 'standard' the only thing they get used for I can think of is that is the thread used for holding electrical household faceplates of sockets and switches to their backboxes.

But a 5BA is pretty darn close if you can get those they would probably fit over a 6mm length.

Nick

[Jasonb]

6-40 UNF is even closer and more readily available to you than BA at only 0.001" larger dia and less that 2tpi finer.

[Davis2x1]

Pete
You can get a 3. 5 mm screw from a BMW motorcycle dealer. They are used on Bing carburators to seal a vacuum port.Part number is 14 13 11 1 259 869.  It will cost you a buck.

[10KPete]

Thank you for all the suggestions. I was having a bit of a melt down yesterday with too many things going on around here.

John, I guess I simply didn't see the listing in McMC. I have ordered those.

The thought that there might be an imperial size close enough to work hadn't occurred to me, Jason. Thank you.

And Nick, I don't think I have even seen a BA fastener here but that's another example of how close different systems can be.

It's amazing the diverse knowledge of the folks here. A screw from a Bing carb used on a BMW scooter..... wow.

I did consider tapping the inserts out to 4mm but that would leave a very thin wall in the brass. Too thin I thought plus they are moulded in and would have required a hand held drill.... not enough control for the size. Too risky. And then I would really have had to rely on JB weld!!

Thanks to you all,

Pete