Thread: Accurately Ground dowels

Hi all,
I spent some time in the shed tonight working on scraping the 2nd side of the Mars's cross slide dovetail parallel with the first side. With my new dovetail measuring tool i had come up with the figure of .0013" out of parallel, but i thought i would check again before i started scraping. I got .0023" out
I checked and re checked but i just could not get any repeatability, it seems within a thou was the best i could get. Turns out the dowels i have that i thought where round are not round at all. Using a v block and indicator they are around .0008" TIR out. I ended up with the largest of my thread wires (about .180") sitting on a parallel on its side. This is repeatable to better than .0002".

My question is, where can i get accurate dowels from? Are the dowels pins you can buy that good?

The guy down the road from me claims to hold size within a 0.0001".
I'll duck out in a minute and see how good he is

Stuart

Hi Ewan,

Josh got some dowell pins the other day from Coventry Fasteners, I'll see if I can find them and check TIR.

Regards
Ray

Have you confirmed with a mic?

The cheap new pins from the store are round better than 0.003mm.

Edit sorry extra 0

Bearing in mind it's cold and dark outside and I have to be up early it was a brief test. While I cant comment on their absolute accuracy I'd say roundness and parallel are within 0.0001"

Stuart

Yes confirmed with a mic, i even got the same numbers....

Thank you for your dark and cold adventure Stu. Where are your pins from?

Hounslow Engineering - page 3
Just down the road from me.

Stuart

Originally Posted by Stustoys

Hounslow Engineering - page 3
Just down the road from me.

Stuart

Stu,

Their website tell us what they do but no more. What size and what price were the dowel pins you bought from Hounslow?

Bob.

Hi BT,
PM sent.

Stuart