Posted by Michael Gilligan on 20/02/2017 16:28:02:
Posted by richardandtracy on 20/02/2017 15:30:53:
The ER11 collet & 13 ER11 collets cost the same from HK as 1 ER 32 collet from Axminster.
.
Richard,
Can you recommend a particular supplier of ER11 kit; or are you convinced that they all supply the same quality ?
MichaelG.
Most of my requirements are for pen making with flexible materials like acrylic, polyester & vulcanised rubber. I am lucky to be able to cut to 0.01mm with these materials as they flex & deform around the tool tip (regardless of how sharp). I normally work to 0.05mm and every seller of chucks, collets etc. seems to better than this level of precision. Which means for my requirements, any supplier seems to be acceptable. I actually used E-Bay seller 'fzeroinstore' for mine: http://stores.ebay.co.uk/fzeroinestore/
Where I have tested concentricity in the lathe, I have noticed the needle of my dial gauge move as I turn the spindle, but indicates less than 0.01mm deviation in a complete turn. I suspect this is adequate for most purposes. At work we usually specify machined items to +/-1mm in non critical areas, +/-0.1mm in more critical areas and tolerances specified by suppliers of mating parts for everything else, so on my pens at home I have a smaller tolerance limit than the company's normal best work.
My current selection method for ER collet tooling is 'Lowest price including post & packing', and so far, I've not had problems that are attributable to the tooling. Where I have had problems, it's usually attributable to the idiot controlling the lathe (me) or the material being less than homogenous and departing from normal behaviour in a big way – disintegrating pen parts make you duck pretty fast! Pen blanks such as these: **LINK** are made by thin partially cured sheets of resin being dipped, prodded & poked into tanks of curing resin. Unfortunately they do not always adhere perfectly at the interfaces, and can split/crack at the surface of the inlaid sheet. This is particularly true at threads, where often need to get the thickness of material at the root down to 0.3mm to allow other parts down the middle. If there is a slight weakness at the joint between parts of the blank, it will show up then. 
Hope this is of interest
Richard.
Edited By richardandtracy on 21/02/2017 10:47:22