JOEPRO
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- UK
I have a crank lock tool im making which will have 8mm hollow dowels welded to a 5mm steel plate.
3d print example

This is to accept m8 bolts. But I would like to add a little clearance to the holes and ream them out with my pillar drill once welding is complete.
If I have a 8mm drill bit first - can I step up to say a 8.5mm reamer or is that too large a jump for a reamer? And do "straight" reamers have a small taper on them or is there a specific type / style I should be looking for in this application? I'm thinking that a normal twist drill isn't a great way of enlarging the hole.
3d print example

This is to accept m8 bolts. But I would like to add a little clearance to the holes and ream them out with my pillar drill once welding is complete.
If I have a 8mm drill bit first - can I step up to say a 8.5mm reamer or is that too large a jump for a reamer? And do "straight" reamers have a small taper on them or is there a specific type / style I should be looking for in this application? I'm thinking that a normal twist drill isn't a great way of enlarging the hole.