Thread: Hand reamer problems

Hand reamers can be awkward to use on occasions.
Are you making a tapered hole?
Have you used a tapered drill to the correct size?
Do you have a centre in the end of your reamer?
Do you have a drill press and vice?

Hi pipeclay,

Many thanks for responding.

No, I'm not making a tapered hole. I am using the tapered reamer to create holes to size in front panels of electronics projects - sometimes I need a 13mm. hole for a panel mount socket - sometimes 15 mm for an on/off indication light. The panels are flat and about 2-3mm. thick (hard plastic, alloy, light gauge tin plate etc)

Because front panel components come in varied sizes it's handy to use a tapered reamer because you can enlarge to suit and you don't have to keep a range of larger sized drills to cover the different sizes of components.


No I don't have a tapered drill - I didn't even know such a thing existed!!!

So the hole does not have to be tapered just round.

I have a drill press and vice.

cheers mate

Aha pipeclay,

There could be some confusion here - I did not realise that that some reamers are just like a drill bit that is tapered - but the hand reamer I'm using has straight flutes that run the length of the reamer - so it doesn't look like a twist-drill bit at all.

Sorry I haven't been clear about this but I thought the only type of hand reamer was the straight fluted type.

Because the material you are working with is so thin and you have a parallel hole the reamer will want to wonder.
If the reamer has a centre in the end of it,it might cut better if you can put your workpiece on your drill press table,have a centre of some type that will locate in the end of the reamer mounted in your drill chuck.
Put the centre into the end of your reamer,that way it will hold it square,also it will apply pressure to your reamer as you enlarge your hole,of course this is only good if you can get your material to the drill.
Have you thought of using a step drill,It is a drill that has differing diameters along its length,they come in sets usually but you can buy individual drills to suit a specfic range of hole sizes.
They are commonly used for sheet metal applications.

Thanks for that pipeclay,

yes a step drill would help - I'll go there next.

cheers

It's hard to get real roundness with a multi-fluted reamer. Once it starts to go out of round it won't fix by itself. A D-shaped reamer is reputed to be a superior tool, but I've not used one. Easy to make, might be worth a try, to finish off after getting near size? Some reamers had flutes that were not equi-distant, so didn't tend to go out of round - where are they now? Or, finish off with abrasive. Say, a piece of rod with a hacksaw slot to hold some emery cloth, used with a drill.
BTW, when using expandable reamers on bushes, I stop when it's still slightly tight. In use, the high spots will bed down. These high spots are not visible. If I keep cutting until it seems a nice fit, sure as eggs it'll bed down further and be a sloppy fit. My friend the motor mechanic told me this, and is normal procedure with small end bushes.

Jordan

Hi Jordan,

thanks for your response - the dowell/abrasive paper deal might be a good one to try - the good thing about the hand reamer is you don't have to take the job to the machine - fortunately most of the bits I fit to panels or boxes usually have a flange that may cover up holes out of true.

The other measure that might improve my technique involves drilling a hole slightly undersized first then taking the reamer to it - previously if I needed say a 15mm. hole I would drill a 10mm. hole and then start reaming. Obviously the less you ream the less you go wonky.

thanks mate,

cheers

Doug

Hey Doug,

Did you get your holes the way you wanted?

Cheers
MH

Yes MH - holes turn out closer to true round the less you ream - I mistakenly thought that I'd be able to ream any amount and still end up with a round hole. Once again experience turns out to be the best teacher

cheers