Do my calipers lie?

[Kami]

Guys(and Ladies)

I was wondering what size you would drill the barron/sedona cap. I am sure I have been drilling at 11.5mm as my calipers still tell me that its a 11.34mm dia tube.

Since I upgraded my drill bit I am having trouble getting my tubes in.[:0]

Could it be heat/friction expanding the resin/PR/acrylic (going through a plastic stage, am addicted to skip rats blanks)?

Or was my previous drill bit a mutant super size bit

Or do my calipers lie?

Thanks,

Kami

 

[DCBluesman]

My tubes have always measured 11.50 mm + or - .02 mm. Using an 11.5 mm bit will give you a zero tolerance hole, and only if your bit and the tube have zero variance. The suggested bit (sorry, but it's SAE) is 15/32".

 

[Kami]

Ahhh So my £10 digital calipers do lie, Oh well they have had alot of use.

Thanks Lou,

Kami

 

[Aderhammer]

did you reset the calipers properly? (BTW i hate digitals, i prefer dial calipers)

 

[mrcook4570]

Measure the drill bit with the same calipers for comparison. Don't assume that it is what the manufacturer claims.

 

[dbriski]

Key to me is "Since I upgraded my drill bit I am having trouble getting my tubes in." That tells me the tolerance of the drill bit is a little off, smaller than your old drill bit.

 

[Kami]

Thanks for all the help guys, I think I will have to use a different drill bit.

Cheers,

Kami

 

[ed4copies]

OR, with plastics, use a round file to enlarge the hole just enough for a very snug fit. DON'T do this with wood or antler as the material will contract, naturally.