Could I get help picking a set of reamers?

[shild]

Never owned reamers before. Only plan on making 3/4" scale stuff, but at the very least I need reamers to do the axles holes don't I? I'm looking at them on ebay and the choice is overwhelming. Was thinking about getting an adjustable reamer set but from what I understand you're only supposed to turn those by hand? I don't really understand why. So I've also been looking at chucking reamer sets too but not sure what the biggest and smallest you might need to do a 3/4" locomotive is. Are these sets any good? Don't want a set with a lot I'm not going to use. https://www.ebay.com/itm/Shars-7-Pcs-Se ... SwvxBeQXO8 https://www.ebay.com/itm/BEARD-SOLID-TY ... SwxVlfb-U0

[David Powell]

You do not need a set of reamers, just to build one loco, go through all the drawings and any descriptions of how to build the loco of your choice, make a list of all the sizes you need and buy individual chucking reamers, I expect you will find you need about 5 at most. Adjustable reamers are not necessary, they are fragile in smaller sizes. Regards David Powell

[Glenn Brooks]

You’ll be well served with chucking readers, whatever sizes you choose. Now, you’ll need standard size readers for boring clean, smooth concentric holes. But, Also consider an over and under reamer set to allow you to make slip fit and press fit holes, as needed.

Quite often a reamer set will be less expensive than buying individual pieces, even though you may not ever need every reamer in a set.

And as David has said, always OK to identify the specific ones you need for a job and pick those up as needed.
Glenn B.

[SteveM]

Chances are the reamers you will need will be the 16ths, and maybe a couple of 32nds in the smaller size. No need to buy a complete set.

When you get to larger sizes, you're probably looking at 1/8ths. You likely will never have a use for a 21/64" reamer.

A set that has 64ths is probably not anything that you will take full advantage of.

Looking thru the plans / instructions for a project will probably confirm that a subset will get you what you need, as David suggests.

Anything that is an odd size, you can make a D-bit for that size. LBSC has you making some when building his designs.

Under / over reamers are good. Makes it easy to get a press fit or sliding fit.

Steve

[Greg_Lewis]

Also know that chucking reamers are designed to cut on the end of the teeth while hand reamers are very slightly barrel shaped and cut to size in about their middle. A chucking reamer is not designed to be used by hand while a hand reamer can be used on a chucked piece via a tailstock center.

And a reamer if not used with skill can ruin a hole in a hurry. A carefully bored hole is frequently a better solution if possible.

I echo the caution on buying a set. Buy what you need when you need it.

And here is a lesson I continue to learn: Do not buy cheap cutting tools! Save money somewhere else. Cheapos are too often faulty to begin with, or dull quickly, or have some other problem. Avoid them. Finally, never, ever, buy a used reamer.

[SteveM]

And a reamer if not used with skill can ruin a hole in a hurry.

If your tailstock and headstock aren't properly aligned and you ream a hole, you will be reaming a perfectly tapered hole, so it's not just the reamer. You need to do everything else right.

Don't ask me how I know.

Steve

[milwiron]

As Greg said, "Buy what you need when you need it." You -need- surprisingly few reamers to build a small loco. If you're opening a machining job shop, yes buy sets.

Reamers are far from foolproof. Like any material removing process it takes some education to do it correctly.
Denny

[Greg_Lewis]

I'm going to toss in another comment about adjustable reamers. I bought a set decades ago thinking I could save some money and get many sizes in one. Not. First, the adjustment isn't all that much. Second, the time it takes to fiddle with the adjustment to get it right is not worth the trouble. Third, 99.999 percent of the time I've reamed a hole it is to bring it to exact size and with a nice smooth finish and since the hole is to be right on size, an adjustable reamer is nothing more than an avenue to a mistake. Leaving not more than .010 (I usually aim for about .007) for finishing with a spiral flute reamer is what has worked for me.

[hoppercar]

You really don't need reamers at all, if your machining your own drivers in the lathe, just bore the axle hole to size.

[tetramachine]

I bought a set over over/under from 1/8 to 1/2. Chinese, work well for last 15 years. Larger sizes ebay a name brand, Morse, Regal, others. When making drivers use reamers for the bores. and on size. You need to have a .625 hole to accept a 5/8 guide when broaching the keyways, a .6235 hole will not work.Larger sizes new are real bucks. There are still NOS reamers on ebay at good prices.

[Harold_V]

When making drivers use reamers for the bores.

Not necessarily sound advice.
Reamers, especially when applied by a lathe, have a tendency to yield bellmouthed and tapered holes that are not round. That condition does not bode well for one who hopes to have wheels run perpendicular to the axle, and to not have the ability to wobble. It should be noted that I am NOT saying that one can not achieve acceptable results, however, just that the risk for these less than desirable results exists.

If one hopes to have straight bores that are round, boring for size is a much better approach. It's not all that hard to achieve size when boring gray or ductile iron, which is the material most commonly found in drivers. These alloys, unlike steel, respond perfectly well to minute passes without sacrificing surface finish.

Just sayin'

H

[Greg_Lewis]

Harold is right. I found that out the hard way.