avturphil
Plastic
- Joined
- Jun 12, 2013
- Location
- Bicester England
Hi all. Little challenge for you today - I have a rescued and rebuilt CVA (think UK made version of 10EE, but simpler mechanical drive) which I may have praised rather too highly in front of friends. Anyway, one has kindly given me a challenge since I have such a splendid machine (!) of designing and making a quill shaft and housing for him for a machine that hasn't presently got one (think tailstock but not). I intend to fabricate the body of the housing and mount it first on my mill to skim the base flat after welding, then probably mount it onto the cross-slide of the CVA to bore the housing for a bush, take the housing off again, make the bush (with undersize bore) on the lathe, press the bush in place, then mount back onto the cross-slide for finish boring. My question is - is it better to turn the quill before final boring and then bore to suit the (finished)quill size, or bore the housing bush first and finish turn the quill to suit? Since he wants the best possible sliding fit are there any other techniques or tips to improve accuracy/reduce play, that can be used in a home shop environment? (without going to the expense of sending out for grinding / honing etc). I have heard of heli-laps (helically split long cast iron lapping tubes that are expanded with a tapered mandrel) and understand them to produce very accurate bores, and possible to use at home, but what could be done to true up an OD?
Many thanks, Phil
Many thanks, Phil