Day 3.
I have struggled a bit with the bearings but they are now ready for drilling the fixing holes and final cleaning..
The first one I did was the most difficult, I made the mistake of not leaving enough protruding from the chuck to turn down the 1/8 'flange' on the bearing (is that the right word?). The result I had to remove and relocate in the chuck and this has I think resulted in a slight taper in the bearing, about 2 thou from one end to the other. Also I could not get my head around how to measure down to the flange. The result on the first bearing was I did not turn it down enough or was unable to repeat the same on the other side. The second one I made a much better job of by turning down to the top of the rounded section of the casting and repeating exactly on each cut. I'm sure there must be a way to have measured exactly. on Bearing no 2 I could not detect any difference (taper) from end to end of the bore and was much happier with this one. I am happy that both bores are at 90 degrees to the base and I have tried an 11mm bar through them and it fits nicely with no detectable slop, to my eye anyway. The crankshaft was supposed to be 11.1mm but I will have to make to 11mm now.
They will not look too bad on the model though when assembled (for a first project attempt anyway..)
I struggle with the dti each time and it takes ages to get runout right but hope this will get easier with practice..
Some pics –
The center of the bore marked out. I used this to bring the tailstock center to the punchmark for initial centering.
Resetting the bore to run true after facing and turning the other side.
Ready for drilling the fixing holes and final cleaning up.
Not the best looking I know but I have learned a lot, which is what this project is all about for me..
I would love to know though how I should have measured the turn down distance to the 'flanges'..
Regards
Allan
Edited By JasonB on 31/12/2014 10:20:42