Allen wrench size for FX Impact X Update

I've torn my Impact apart a couple times, and so far the smallest I've needed is a 2mm,The smallest I'm familiar with is the Brass Adapter (A23 and A24 on the schematics from FX) at 2 mm. The largest I think was 4mm or 5mm. You should be fine with a good selection of hex keys in that range.

I would recommend three different sets though, each has a purpose, so you'll end up with three of each size. You can do it all with standard L shaped keys, but a T Handle set and Screwdriver type set will make it easier. The T-Handle really helped and was much faster to use. The screw driver type set is good for some of the tight fits, like the Brass Adapters where a T or L shape really don't work well, but can be made to work.

Also, get the Ball Head design if you can. There are a couple adjustments, like the regulator that really need an offset because you can't go straight in.

I don't have the screwdriver set yet (so you can do it all without it, but it does help), but do have the ball L Shaped keys and a T Handle set. Ball Keys from Harbor Freight are about $8 and the T Handle Metric set are about $7. The screwdriver set can be found on Amazon for about $13.

the right tools will make all the difference in the world!

If you get in a bind, the folks at FX are great, and you can arrange for a tech / gunsmith to call you back. Might even get Ernest! The MasterClass for the Impact is an incredible resource, highly advise watching it before you do anything.

For trigger blade adjustments on some guns a 1.27 mm is a handy little wrench size. I have 2, one straight and one ninety degree.

There's a couple of kits on Amazon that include both metric and SAE. They're cheap and have served me well. Not super duper quality but for the price, they're kind of hard to beat. Smaller on the small end and larger on the large end than you'll need on an Impact. Check them out!

Stoti



















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I haven't done any valve work on an impact x, but the original impact had a 1mm allen set screw on the valve assembly. 

I would get one if planning on a complete teardown, better safe than sorry for $2.

Hope this was helpful.

And the hex for the valvestem grubscrew is also a 0.9mm on earlier models, at least mine is.