I have one of these;

which doesn’t do larger bearings.

I bought some additional aluminium machined parts to increase the range of bearings it’ll work with off here and although they’ll go over the threaded part of the press they’re fractionally too small to go over the non threaded area. I knew this when I bought them.

The hole needs to be a slightly over 16mm.

So, to enlarge the hole ‘a tad’ is one of these the right tool for the job;

http://www.ebay.co.uk/itm/Expanding-Adjustable-Hand-Reamer-Tool-15-08mm-to-16-66mm-H6-Ream-Milling-Lathe-/141238616255

I guess using this tool it’s best to take a small amount of each time to stop it digging in and keep the hole central?

I’ve got the ‘T’ bit holder thing from a tap and die set to hold the end. Do I need any cutting compound or anything (oil?) on the blades when I use the tool?

I’d just drill it with a 17mm, the tolerances don’t have to be close.

dripping oil in occasionally

Yup,the reamer will be fine,a small amount each time and use oil.
How much is a tad ?

Nice tool to have if you like tools but overkill for the job. Sounds like a few strokes of a file might do it.

A squirt of WD40 or paraffin will help. Do you have a drill press rather than a tap wrench? It will take ages manually (failing that I’d chuck it in a battery drill).

I’d just drill it with a 17mm, the tolerances don’t have to be close

I started with that idea and then thought;

1) I’d have to buy a 17mm drill bit anyway (probably a blacksmith’s bit as I only have a 13mm chuck) so cost is no different.
2) I wouldn’t be certain I’d got it central in the existing hole, even using the pillar drill, and I’d worry about it ‘catching’ and taking a chunk out as I’m only trying to increase the hole size by a little and then it woudl be ruined internally.

it really only does need increasing by half a mm or so.

I’ve got 6 of the parts to do in total.

I’d go for the reamer. Do all the bits at each setting before adjusting.

If you can’t find someone local with a lathe,post them up here and I will do them for you 😉

that’s a lovely offer fasthaggis, thank you, but I quite like the challenge of trying to do stuff like this myself and a tenner for the tool to do it seems like a fair price for an hour or two’s entertainment in the garage 🙂

“I’m only trying to increase the hole size by a little and then it woudl be ruined internally”

defined ruined .

where can you get a reamer for a 5er …. if your paying more than a 5er for a blacksmiths drill bit your overthinking it….. for a one off – different if it was a production set up the skys the limit for long lasting drill bits.

Indeed ,just make sure that you can hold those aluminium bits firm 🙂

where can you get a reamer for a 5er ….

Did you open his link? £7 right there.

1.6 mm drill bit.

?

defined ruined .

I guess with chunks taken out where the bit’s caught. I know it wouldn’t stop it working but I’d see it every time I used it.

there may be a quid or two difference between the bit and the reamer but I’d get ‘the right’ sized hole with a reamer which would be worth it (to me).

I increased a 25mm hole to 25.4mm (in aluminium) by rotating a half round file in it. Didn’t take that long as you are only skimming 0.2mm.
Do you have a small half round file?

Assuming it’s an ally part, I’d be running a file up and down it a few times.

Reamers are only designed to take a very fine shaving off.

On a similar but separate note, I’ve got a DIY headset press, but really want to make some ‘stepped bearing presses’ like the bits on to OPs..
at the moment I’m using flat washers, which don’t always sit central.

Apart form a chunk of alu and a lathe, any suggestions??

DrP

Some of these;

http://www.ebay.co.uk/itm/8-50mm-diameter-x-5mm-thick-aluminium-discs-/301390731770

and a hole saw with the right internal diameter to cut the outer diameter and a drill bit for the centre?

Quick update, reamer turned up yesterday and I just spent a fun 20 minutes spinning it around in bit’s of aluminium 🙂

Fit the press a treat now

How much is a tad ?

Well, in space terms, it’s about half a million miles.