Supplier wanted for M3 x 85mm black hex bolt

[Psi]

So i'm looking to buy 400 machine screws but my requirements are outside the norm in terms of length.

* M3 (M2.5 or M3.5 would probably work too)
* 85mm long +/- 2mm
* Either hex head or hex cap
* Black color

Does anyone have any recommendations or sellers on aliexpress they have used before to order odd length bolts?

I have found one person selling them but they are a custom part for a RC car in a box of 6. They want US 80 cents per bolt for 400 qty, which seems very high to me.
I think 10-20cents in 400 qty is more reasonable.

Any recommendations?

[timelessbeing]

Could you use threaded rod with nuts at both ends?
https://www.banggood.com/500mm-M3-to-M12-Stainless-Steel-Threaded-Rod-Screw-Rod-p-1028865.html?cur_warehouse=CN

[Psi]

Sadly a threaded rod is a no.
The bolt head is on the front panel of the product, so it need to look clean.

[rx8pilot]

The longest M3 at McMaster Carr seems to be 60mm - which is already crazy lengthy.

No chance of using a stand-off as an extension?

Short and misplld from my mobile......

[Psi]

The longest M3 at McMaster Carr seems to be 60mm - which is already crazy lengthy.

No chance of using a stand-off as an extension?

Short and misplld from my mobile......

now that is an interesting question.
I don't think it would fit unless it was a super thin extension, but worth looking into.

It needs to go through a small gap in an extruded aluminum case to hold on the front and rear panels.

The case is not threaded and is supposed to be used with small thread-forming screws. but i really hate this approach. It's time consuming and requires cleaning to remove all the ground metal it creates.
Which is why i'm looking into a long bolt that could just go through the entire thing.

[Brumby]

Sadly a threaded rod is a no.
The bolt head is on the front panel of the product, so it need to look clean.

Domed nuts?

[sleemanj]

Here's a taobao vendor with various long sized m3. No reccommendation, have not bought from them, just a quick google from my tablet, looks like they do different styles including black buttonheads in one picture, probably could find other sellers there.

https://item.taobao.com/item.htm?id=13385048208

You can always cut down longer ones.

[cleanworkbench]

I know a place in the UK but postage might be prohibitive though , very nice people .
When i was visiting there he had a whole stash of blackodized fastners , email  and see

Here is a link

https://www.barenco.co.uk/

Hope this helps out.

[mikeselectricstuff]

I've used M3 tri-lobe screws in the past for ali. extrusions - should be less likely to create swarf.

 https://uk.rs-online.com/web/p/self-tapping-self-drilling-thread-forming-screws/4831218/

[Nusa]

If you're willing to enlarge the mounting holes a bit, you could install M3 rivet nuts.

[Psi]

Thanks guys.

Threaded rod plus rivit nuts might work.
Assuming I can find m3 85mm threaded rod

[mikeselectricstuff]

Thanks guys.

Threaded rod plus rivit nuts might work.
Assuming I can find m3 85mm threaded rod

That's readily available, typically called "studding"
e.g. http://uk.farnell.com/duratool/st01030100081fa/studding-zinc-plated-m3x1m/dp/517320?st=m3%20studding

[Psi]

OK,   i have this sorted!!

3mm plastic tube from aliexpress,   It's like $9 for 100x 50cm lengths.
This fits snug into the untreaded holes in the aluminum extrusion (its intended for M3.5 thread forming screws)

Then self tapper screws ~16mm long (which i can easy get in any color/head type cheap as)

They bite into the plastic tube and force it outwards like those concrete plug insert things.
Works amazing and very tight.

So this issue is now sorted

[rx8pilot]

Excellent solution!

No exotic screws, no metal chips falling on your pcb..... nice.

Short and misplld from my mobile......

[woodchips]

I have often used

http://www.gandbprojects.co.uk/product/9/category/9

who make just about anything small and threaded.