Tapered hand reamers

Metalworking questions in this section please

Moderator: Moderators

Post Reply
Newly registered Member
Posts: 30
Joined: Sat Dec 16, 2017 11:55 am
Has thanked: 19 times
Been thanked: 0

Tapered hand reamers

Post by BSM-Williams »

I want a friction fit hole. So i can push a metal pin into a tapered hole and it fits snug.
With a hand reamer, especially a tapered one is the stated size at one end or in the middle?

If i want a 6.2mm hole, do i buy a 6mm reamer as it starts at 5.9mm and finishes at 7mm and the 6mm is at the thinner end or do they go from 5.5m to 6.5mm with 6mm in the middle?

or a 6mm reamer starts at 5.7mm and stops at the end of the taper at 6mm.

so to get a 6.1mm hole i need a 6.5mm reamer

also the angle of the taper is 1;50 normal or is 1;100 normal?

how understanding is Cromwell's at west brom, when idiots walk in by the way??
I am looking to buy the reamer and drill at the same time as a set for a 6.1mm or 6.2mm hole and a 6.8mm hole
User avatar
Senior Member
Posts: 2365
Joined: Fri Feb 26, 2010 11:16 am
Location: Ash Surrey
Has thanked: 124 times
Been thanked: 399 times

Tapered hand reamers

Post by aeromech3 »

My taper reamer has 7/32 stamp and measures same at thickest end.
User avatar
Senior Member
Posts: 4886
Joined: Wed Feb 25, 2015 7:20 pm
Has thanked: 1234 times
Been thanked: 1110 times

Tapered hand reamers

Post by Dave54 »

If you look on the Cromwell tools site there are details of the reamers
https://www.cromwell.co.uk/shop/cutting ... r%20reamer
and pins
https://www.cromwell.co.uk/shop/fastene ... per%20pins

Metric are apparently 1:50 taper
Imperial 1:48
According to the site.

TBH the last time I used one was so long ago that I've forgotten sizes and so on.
These users thanked the author Dave54 for the post:
BSM-Williams (Fri Apr 02, 2021 4:01 pm)
Rating: 7.14%
Post Reply

Return to “Metalworking Forum”