RC Tank Warfare community hobby forum

Is there a smaller allen key size than 1.5mm?

Just that I've a grub screw on a pinion gear and my 1.5mm doesn't fit.

Might be imperial maybe? gear is Ansmann so not certian if their metric or imperial.

grub screw size for you allen key is 1.5 ..they don't do a smaller fitting on them..

May be if it was factory fitted, lock tight has gone hard in the head of the screw.., just place a soldering iron to the top of it and that should melt the thread lock..

if not thread lock stopping it..get a pin and clear the head as there sounds like some thing there that shouldn't be.

Hope this helps a little.

Cheers Caddyshack,

It is new gear and screw. Might be the screw is misformed, as I bought 2 one for each motor and the other didn't even have a hex in it.

I just ran into the same issue with a Schumo gear reduction set, the pinion set screws were smaller than 1.5mm.
The set screws turned out to be 1.27mm, I found an allen wrench in that size at Harbor freight and it fit perfect.

Well the shop is sending me another grub screw for the defective one, they've confirmed it should be 1.5mm. But i've checked again on the one I have and no way will the 1.5mm fit.

Buckeye36. 1.27mm strange size but I'll have a look to see if I can find one.

Was thinking tankbear..if you have been using those cheap "L" shaped keys ..Then a burr could be on the end of your key stopping it from going into the grub screw.. They normly just round off but you may have one or 2 of the outer egdes pushed up.

caddyshack wrote:Was thinking tankbear..if you have been using those cheap "L" shaped keys ..Then a burr could be on the end of your key stopping it from going into the grub screw.. They normly just round off but you may have one or 2 of the outer egdes pushed up.

I check it out caddyshack. But think it is an odd ball small size as I last used the allen key (yes the cheap L shaped one) too tighten up a few grub screws in the Mato gearbox and was fine then.

OMG is it me which attracts problems. Or does everyone have this much?

Got my replacement grub screw for the pinion gear, fits the 1.5mm allen key perfectly, can I get it too screw into the pinion gear? NO suspect the thread hasn’t been tapped properly.

Don’t know whether to contact shop again and ask for a replacement gear or to buy a tap, and rethread it myself.

Is it a 2mm tap?

If you haven't a tap set..try a wire brush in your dremel at a medium speed into where the grub screw goes, then cover the grub screw with copper slip and try getting it started with a steady hand.

caddyshack wrote:If you haven't a tap set..try a wire brush in your dremel at a medium speed into where the grub screw goes, then cover the grub screw with copper slip and try getting it started with a steady hand.

Cheers for the tip caddyshack.

Don't have tap at moment but ran into simular problems with Asiatam hull with bad threads and grub screws so was thinking of thinking of getting the tap and some grub screws for the box as no doubt will come up again.

Was looking on Ebay and looks like grub screws are m3 with 1.5mm hex head. Is that correct or do they come in different diameters to add more confusion to me.