First Proper CNC Router

[Voicecoil]

What's the orientation of the sections you're joining? Do you have plates/brackets? (a pic or drawing might help) Either way, 4 x M5's sounds a bit light duty to me, do you have room to go up in diameter? Properly done with the correct surface preparation and curing, epoxy can give a very strong bond - seems to work OK in aeroplanes :-)

[diycnc]

I'm not in the workshop at the moment, but take a look at the pic in post 36.
Agree 4 x m5 isn't enough, and I dont think there is room to go up in diameter. The existing bolt holes are a little too close to the side walls to go up in size.
Will try some thin slow setting epoxy on a test piece befor I apply to the frame

[Voicecoil]

I'm not in the workshop at the moment, but take a look at the pic in post 36.
Agree 4 x m5 isn't enough, and I dont think there is room to go up in diameter. The existing bolt holes are a little too close to the side walls to go up in size.
Will try some thin slow setting epoxy on a test piece before I apply to the frame

From the pic. and the few screws that are visible it looks like there might be a bit of room to go larger - but then again it's not a close-up, so do check it. If you're using slow setting epoxy do check the manufacturers curing instructions. Araldite Precision for instance cures with better strength at a slightly elevated temperature - as well a a lot quicker. And remember that once it sets you can't adjust stuff any more - so make sure everything gets properly lined up!

[JAZZCNC]

You are always going to have this problem even with larger bolts unless the holes are reamed and a very close fit to the bolts. ie Sholder bolts. It will be to a lesser degree because you'll have more torque with larger bolts but still it could move. Epoxy will help but only upto a point, it certainly won't hurt until you come to take it apart again or decide to weld it up, then it will be a bitch to get off.!!

Don't you know anyone with a welder.? it will take 20Mins max to weld those few pieces together and it will be so much stronger. Forever.!!