Need some help and advice, ideas for finishing a detail

[Boyan Silyavski]

Hi,
i have designed something and just doing some tests. The part is made from 5mm aluminum and has a detail that is 15mm long and 5mm wide/same as material /




Now the problem lies that the protruding part has to go inside into a couple of bearings with ID6mm, meaning i just have to scrape say 0.5mm from corners so it could fit.

Cause of this, i have to make a fixture and turn the part over. Otherwise the part could be machined only one side /actually both sides, but one side is facing, then flip and machine,thats for better precision/.
And be very careful.



I need a simpler way to do it. I have thought and invented some complicated ways , like:

-making it longer , fit on my small lathe and finish,though i have to search and buy new 4 jaw chuck for this. By the way-self centering or not???
-make fixture , screw this inside, then the round fixture on the lathe and so on.





But i am not happy as it must be precise/ better than 0.05mm/ and it would take quite an additional time for all.

I was thinking, if exists something that could help me scrape it simply to shape by hand, that would self guide the 5mm square to 6mm circle. Or something similar. may be it exists already and i just dont know how is called




Bellow some pictures so you could understand the problem. It seems stupid to flip machine 100 parts only to scrape 0.5mm.

Any ideas?