Building My First CNC Router, Looking for Advice & Other Info

[Desertboy]

Hi @Desertboy,


I remember you saying previously that you had ordered extrusion from KJN, out of interest did you need to tap the holes in the ends of the extrusion? I thought those holes were sized for an M10 thread to be tapped but they are too big, not sure if there is enough material there to get a M12 thread tapped. M11 seem expensive and the site where i have ordered my fixings from don't supply M11.

Thanks

Alex

Hi I was convinced they were M10's (You maybe got that from me) so holes I had drilled were too small in the end I widened them myself. I never tapped the ends I used M12 bolts and drove them in using an impact driver and stainless steel A2 socket caps was still hard work with the impact driver lol but only took 15 minutes just heavy on the hands.

I used the T nut 90° corners to assemble at right angles the frame before I drove the bolts in then undid the corners and moved on to the next piece to try and keep everything as straight as possible. This was especially important on the bed frame which wants to twist when you drive the bolts in.

I recessed the gantry into the aluminium which removed any twist when I drove those bolts, when I tightened the gantry mounts to the Hiwin carriages the gantry sat it fine without any bolts perfect fit this really made it a lot easier. In fact if you don't recess I doubt you could do it the way I did. I have a 5mm recess either side in 20mm tooling plate.

I think it turned out ok




It could be done with a bar and a lever (I did a few like this) but it's very hard work. You could also drill the internal out with an the correct sized drill bit (Guessing 10.5mm or 11mm) then it'll be easier to tap.

In retrospect I should have had KJN tap it.