Adjustable versus sized reamers.

Topics include, Machine Tools & Tooling, Precision Measuring, Materials and their Properties, Electrical discussions related to machine tools, setups, fixtures and jigs and other general discussion related to amateur machining.

Moderators: GlennW, Harold_V

AllenH59
Posts: 479
Joined: Wed Mar 16, 2011 1:26 pm
Location: Prince George BC Canada

Re: Adjustable versus sized reamers.

Post by AllenH59 »

John Evans wrote: Thu Nov 18, 2021 2:56 pm
AllenH59 wrote: Thu Nov 18, 2021 1:55 pm Does anyone use these under power? my lathe will go pretty slow, 50 rpm, and I have a vernier on my tailstock so I could see how fast I was feeding. I will have time to think about it, as the flooding in British Columbia has no doubt tipped the supply chain, and the ones I ordered from India will not be here any time soon.
I would not recommend using adjustable reamers under power !! The way they are made renders them somewhat frail, the adjusting nuts are a case in point. Use a correct fitting wrench if at all possible as I have seen more than one reamer with the adjusting nuts ruined to un-usability with the nuts deformed from using pliers or poorly adjusted Crescent wrenches. Also in the smaller sizes for sure use a tap wrench to turn them with, the square end on the smaller ones is easily ruined. And when you raise a chip that locks the reamer from turning do not rotate backwards, ruins the edge. Release the pressure by just BARELY moving in reverse ,pull reamer and adjust to a smaller cut and clear the burr. Like I said those adjusting nut are frail ,they only need to be snug enough to keep the blades in place. I rarely lend out my adjustable reamers only to people I know will follow my instructions on proper use !!
John, I am not a tool lender. If you are a good enough friend for me to lend you a tool, you are a good enough friend for us to use it in my shop, and we will make the required cut. I would rather donate my time to a friend than have something come back damaged. Plus it is always good working with my friends.
User avatar
Bill Shields
Posts: 10464
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: Adjustable versus sized reamers.

Post by Bill Shields »

Customers that need a little more clearance on pins gets a bridge reamer shoved through the hole....or a drill :mrgreen:

I have never thought of "a little more clearance" as a reamed fit.
Too many things going on to bother listing them.
User avatar
liveaboard
Posts: 1971
Joined: Sun Dec 08, 2013 1:40 pm
Location: southern Portugal
Contact:

Re: Adjustable versus sized reamers.

Post by liveaboard »

I don't use them as much as I used to, now that I have a lathe and a mill.
But in the past I've done good work with adjustable reamers; grease fit holes and press fit holes are easily done, and on site if necessary.
Things I made 25 years ago are still in service.
AllenH59
Posts: 479
Joined: Wed Mar 16, 2011 1:26 pm
Location: Prince George BC Canada

Re: Adjustable versus sized reamers.

Post by AllenH59 »

LIALLEGHENY wrote: Thu Nov 18, 2021 6:41 pm , many jobs don't warrant the expense of buying a new reamer for one hole, maybe to never be used again.

Nyle
That is my feeling about them, I ordered an offshore set up to 1.5", Usually I can bore holes on the lathe, I do have a 12 inch 4 jaw, and can set a fairly large fairly awkward piece in the chuck to bore, but like every one else.. once in a while.. I am hoping that it works for bearing fits. Once in a while build things that have several bearings the same size, and it might be nice if I could get a reamer set to the right size, and finish the holes with it. It is in the plans to make a floating reamer holder for this. it is all an experiment, as is my whole shop, as I bought a 16x48 inch lathe brand new, with no experience 20 years ago and went from there. I have a buddy who is a fairly new hobby machinist, who wants a set of reamers for tap drill sizes. He is pickier than I am.
John Evans
Posts: 2366
Joined: Tue Jan 20, 2009 9:33 pm
Location: Phoenix ,AZ

Re: Adjustable versus sized reamers.

Post by John Evans »

[ Once in a while build things that have several bearings the same size, and it might be nice if I could get a reamer set to the right size, and finish the holes with it."

You will find a .001 cut is a big cut for a adjustable reamer as they cut along the length of the blade ,regular chucking reamers cut on the very end and .004 to maybe .010 is the usual allowance for reaming with these. Power reaming with a adjustable ? good luck there let me know that works.
www.chaski.com
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Adjustable versus sized reamers.

Post by Harold_V »

AllenH59 wrote: Fri Nov 19, 2021 10:13 pm I have a buddy who is a fairly new hobby machinist, who wants a set of reamers for tap drill sizes. He is pickier than I am.
Sigh!
What does he hope to gain by using reamers?

I was trained in a facility that was building a guided missile. Each and every part received 100% inspection, and the results determined if parts were scrapped or used. Everything, including hole size, was inspected. We were taught to double drill holes, so unless one is trying to hold an exceedingly tight tolerance, or achieve a finish better than one provided by a twist drill, a reamer simply isn't necessary.

If a hole is opened near size (within .015" or less for small holes), then taken to size with a sharp drill, it is unusual for the hole to be oversized. Double drilling works, and very well. Your friend would be so much wiser to put his money in other places. That's assuming he isn't blessed with too much money, anyway.

Might not hurt to point out to your friend that the minor diameter of tapped holes does NOT make contact with another surface. So long as it's the right diameter, it is good. Double drilling does that for you.

H
Wise people talk because they have something to say. Fools talk because they have to say something.
AllenH59
Posts: 479
Joined: Wed Mar 16, 2011 1:26 pm
Location: Prince George BC Canada

Re: Adjustable versus sized reamers.

Post by AllenH59 »

Harold_V wrote: Sat Nov 20, 2021 3:02 am
AllenH59 wrote: Fri Nov 19, 2021 10:13 pm I have a buddy who is a fairly new hobby machinist, who wants a set of reamers for tap drill sizes. He is pickier than I am.
Might not hurt to point out to your friend that the minor diameter of tapped holes does NOT make contact with another surface. So long as it's the right diameter, it is good. Double drilling does that for you.

H
My friend is a master blacksmith. He has a power hammer and a forge, and can make any thing you can imagine. He is also has a B welding ticket, which qualifies him to to weld on pressure vessels and pipelines. He is a handy friend to have when I want something welded, and to look nice. He bought a lathe and a milling machine in his late 60's, and has never been introduced to the notion of "+/-" when measuring. He imagines all machined parts are meant to be exact. So naturally he would like to start with nice, straight, round, smooth holes to cut threads in.
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Adjustable versus sized reamers.

Post by Harold_V »

Good enough. I'm anal about some things, too. Hole finish for tapping isn't one of them, though. So little of the hole remains once the thread is generated that it borders on the impossible to determine surface finish, thus my comment about size established by double drilling being more than adequate. However, to his credit, straightness can be determined via the use of drill blanks, and that is one thing a reamer can correct.

To be clear, I don't have a problem with his objective--it's just generally not a problem under all but very unusual circumstances. Likely never for the typical shop project. But then, who knows?

H
Wise people talk because they have something to say. Fools talk because they have to say something.
Post Reply