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Ueee
14th May 2013, 08:57 PM
Hi all,
Now i have my 2 taper pins made for tramming the Verniers head, one thing is clear. The head is not precisely trammed with the pins in! I have to pull the head off again and check there is not a tiny chip anywhere inbetween the mating surfaces, but i doubt it.
The pins are a 1:20 taper, and so far the only reamers i can find are for timber, they use 1:20 for stringed musical instrument tuning pegs....
The other option is to make a reamer from some silver steel, once hardened it should manage the 2 holes.

Has anyone seen or heard of a 1:20 reamer, or has any wisdom on making one i would be grateful.

Cheers,
Ew

KBs PensNmore
14th May 2013, 09:08 PM
Do you have access to a grinder that can do tapers, if so what about using a drill bit ground to the taper required. To grind a tapered reamer from blank steel could be more work than necessary.
Either that or grind a spare reamer, you'll probably use it again somewhere!:D
Regards
Kryn

bob ward
14th May 2013, 09:52 PM
FWIW the taper on centreline of standard imperial taper pins is 1:24 and for metric taper pins it is 1:25

Brobdingnagian
14th May 2013, 10:08 PM
Jarno Taper is 1:20

some examples here.

Helical Jarno Taper Reamers (http://www.newmantools.com/reamer/SchedulU1.htm)

-Josh

Keith_W
15th May 2013, 06:57 AM
Hi Ueee,
I have quite a number of Tapered Reamers and several No2's, send me your address and I will post one to you as I dont need them all.
Regards,
Keith_W.

Ueee
15th May 2013, 08:42 PM
Thanks for the replies guys,
Its good to know the Jarno is 20:1 Josh, makes it a bit easier.
Bob, just to make it clear its 20:1 total taper, much steeper than the standard taper metric or imp.
Nothing more than bench and angle grinders here Kryn, but i like the drill bit idea.

Keith, that is a fantastic offer, once again a big :2tsup: to the spirit of the forum! I think in need a #3 but i'll PM you about it.

Looking at the price of the Jarno reamers i might try making a D style reamer first.......

Cheers,
Ew

azzrock
16th May 2013, 11:53 AM
would a 3 deg tapered drill work?