Help with reamer tolerances, H7

[RaceDiagnostics]

If I buy a 8.99mm H7 reamer, what is the minimum and maximum size that it can be and where can I find this out?

 

[Member 32799]

8.99 +0 +0.015

 

[voipio]

Do you mean the size of the tool or the size of the holes it makes? The latter depends on the material to some extent. The answer is, apparently, in the DIN206B standard for hand reamers. Yours, a snip at around 30 Euros.

The Zeus Data Charts and Reference Tables mentions H7, amongst others, though not specifically for reamers, just the general basis for fits of different types. For holes between 6 and 10mm diameter, this gives the H7 size range to be the nominal value plus 0 to 0.015mm, as . mentioned.

This link may help a bit:

http://taylorandjones.co.uk/wp-content/uploads/2014/03/31-40_technical_section.pdf

 

[RaceDiagnostics]

Thanks, I was trying to understand the size of the tool. Who knew holes were so complicated.

Assuming you measure the reamer, can you conclude it will cut a hole of the same size in aluminium?

 

[ronan]

Thanks, I was trying to understand the size of the tool. Who knew holes were so complicated.

Assuming you measure the reamer, can you conclude it will cut a hole of the same size in aluminium?

Depends what you use for lubrication/coolant, suds or dry will give you a smaller diameter hole than if you use something heavy like neat cutting oil or Trefolex.