Reply To: Heat a bolt if the tube is too tight

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Thanks for the feedback.

The centre assembly I have printed is the new latest one which is very comprehensive and well designed. Went together like a dream, but it does not, however have any ‘give’ to bluff the oversized stainless steel. While the Z axis can be ‘forced’ into accepting the oversized steel, the X & Y portion does not have any give. Forcing the steel in is what I think Allted refers to when the alignment is out. It is surprising how much deflection there is for a mere 0.4mm extra diameter. You do not feel like you are forcing it, but you can see the bearing arms physically and visibly deflect, so you know there has to be a consequence for that deflection.

I am gambling on there being no nasty “side effect” from tolerances, and hoping to track down a 8.4mm drill bit which will then give the 0.2mm extra clearance per hole if I assemble and tighten with the steel in place.

I found a company here in Cape Town that does a vast range of HSS drill bits, I needed one to drill out the heat-sink for the 2.8 Watt Laser (L-Cheapo – The assembly stated it needs a 7/32″ or 15/64″ drill bit which is only 6.4mm which is WAY too small.) and ended up buying an 11.7mm HSS drill bit (9/16″). Horridly expensive (as much as a 6m length of 308 25mm stainless steel), but did the job. I will go through tomorrow and see if they have anything to allow me to drill out these bolts holes, and hope that the PLA is forgiving as I know it does not like to be drilled.

If that works, then I will try and sand out the leg brackets which I see in another post that someone made there own sanding drum to do this. Other wise reprint at a scaled up size.