Guys, I need a 10.85mm hole in 2mm aluminum to press-fit a F694zz bearing and have no idea how to obtain this hole size as long as drill bits are either 10 or 11 and maybe there are some specialized 10.5 (which i don’t have).
I am thinking about a few paths:
scientific approach: heat the metal and drill hot with 11mm drill bit so that when contracting the hole gets to the desired dimension (is it even possible to calculate this?)
use the non-perfect rotation of any drill bit that will result in a larger hole than intended due to wobbliness
hammer the sucker in a 10mm hole (which will result in a tad larger hole (maybe 10.5mm) due to bit wobbliness.
0.15mm is going to be a brutal pressfit and nothing you’ll be able to properly fit without a real press. How about going with a 11.0mm bore and an adhesive? You can get specialized adhesives, similar to threadlock, that are made for this exact purpose.
@Thomas_Sanladerer That can work but for a one-time job seems unnecessary to buy the threadlock-like adhesive unless it is really threadlock I can later use in other projects.
Reckon going with @Thomas_Sanladerer ’s idea is a good one. Whilst you may only need the adhesive for this one job now, I can guarantee it’ll come in handy later, on the other hand, you could always make or buy a mount for your bearing then the hole could be whatever else you want.
@Thomas_Cox
Hmm you’re right, I can get a 10.8mm bit for around 3.6Eur + shipping so around 5Eur… who knew.
No hole in the pocket but useless bit after this.
@Florian_Ford You can try using the thermal expansion trick as well with the 10.80 bit however when you look at the CTE for aluminum you’ll find it is very small. ~23um/m*°c.
All the methods mentioned by the people here are easy and fast and very ok for a 1-time-job. In the time you answered here again and again, you would have already finished any of the methods told
I know. I’ll do that tomorrow though (not working on Sundays ). + I wanted to pick a bit the brains of the engineers here which is a good way to learn.