Well I just sanded one side of the y carriage prep it for polishing it was time consuming but worth it just need get more sand paper from
Here before pic
Heres after pic
Anyone in the uk thinking about making the prusa i3 I can get the 6mm aluminium frame for 60 inc delivery the only two problems with the frame 1 the holes are 3.25 (which I believe someone changed it on the github to 3.25mm they should be 2.30mm) Ive tapped mine out to 4mm and adjusted rp part files where necessary and 2. I have a minimum spend order of 100 but lead time is 7 working days due too supply and demand
Have a look at the 2nd frame being built by richard_j_m
prusa i3