I am not a gunsmith. I did have about 3 years training in machine work when I was young. I'm now retired and want a machine to do hobby work. It'll probably be use to thread barrels or more for drilling and modifying mounts just minor stuff. The question is which of the combo machines is the best. I know there are a lot of really good gunsmiths on here please share the knowledge.

Those are very tempting machines, but many are not easy to use for gun work.

Most that I have seen will not go slower than 150rpm without you installing a variable speed setup, or reworking the gear/pulley system. Threading at 150rpm is doable, but not for the faint of heart.

I learned on a smaller 150rpm machine, but when I bought my lathe, I got one that goes 20rpm if needed. I don't crash it anymore.

A 12X36 is about right for a small shop, a 13X40 will do anything needed. The RF45 class mill/drill machines are surprising in what they can do if you don't push them too hard.

Of the combo units out there, Smithy has the only ones with enough capacity to do the work. How precise they are I do not know. I have never worked with one.

Jeremy

I threaded a barrel at 150 RPM on my Chinese 9x20... never again!

I think you would be better off with a 1024-1440 lathe and a good drill press. That is until you can afford a knee mill. For drilling and tapping actions there are jigs you can buy for drill press use that will do the job.

150 too fast? I thread at either 240 or 325. I've never threaded at a slower speed than those, but I use carbide insert threading tools.

Too risky for me!

quote:

Originally posted by Toomany Tools:
150 too fast? I thread at either 240 or 325. I've never threaded at a slower speed than those, but I use carbide insert threading tools.

That takes some serious coordination there! Not me man!


.

quote:

Originally posted by Toomany Tools:
150 too fast? I thread at either 240 or 325. I've never threaded at a slower speed than those, but I use carbide insert threading tools.

Up to a shoulder?

I had this, about 20 years ago .. thought it was a good idea, until i got it
http://www.grizzly.com/product...mbo-Lathe-Mill/G9729

it is great for nothing, a decent lathe, and everything else is meh ...

quote:

Originally posted by montea6b:

quote:

Originally posted by Toomany Tools:
150 too fast? I thread at either 240 or 325. I've never threaded at a slower speed than those, but I use carbide insert threading tools.

Up to a shoulder?

Hell no! 40 years ago I attended Springield Technical Community College, Springfield MA, pursuing a degree in Metals Processing Technology. We studied in what had been Garand's pattern shop, and this is where I leared to operate a lathe. Our professor taught us to thread upside down and backwards (the tool, not the operator) and this is how I've always done it. I can thread the "normal" way, but do so so rarely I can't even remember the last time I did it. Of course, this means every thread I cut sports a relief cut, but that's never been an issue. You can cut at much higher speeds and its a lot easier to get nice finishes, and on top of that no risk of a crash.

quote:

You have to be mighty fast on the draw to stop a 10 TPI thread against a barrel shoulder at those spindle speeds

I had an old smith try and try to teach me 40 yrs ago. Yes I got so I could cut nice threads. Never got comfortable. So 10 RPM sounds about right. Matches with the TPI.

Why can't you thread to the shoulder and disengage the half nut and then leisurely pull the cross slide out? I don't use a thread relief. Can you give me the pitfalls from doing this?

 Our professor taught us to thread upside down and backwards (the tool, not the operator) and this is how I've always done it. 


This.

Adam

quote:

Originally posted by dpcd:
Butch, sure you can thread to the shoulder; disengage the half nut and back the tool out. I still cut a relief groove because you don't want to actually hit your shoulder with your threading tool. And you are actually cutting a relief groove too; just with the threading tool, you are cutting a one thread groove. You still will have to make your shoulder clean and sharp for receivers that don't have the thread relief there. But most people don't do it at 300 RPM and coarse threads; at least not for the mortals among us. Like me. I usually thread at 90 which is actually faster than some/most do.

You are correct. I have a thread groove a very few thousandths from the shoulder. Very very few receivers have threads right to the face of the front receiver ring. I don't thread at a fast speed as I no longer do it for money and I can take as long as I choose. I do use Warner HSS threading inserts. They make a beautiful thread.

All Mausers do.

quote:

Originally posted by dpcd:
All Mausers do.

Well, maybe most, but mine aren't.

I have a Banner mauser, 1909 Argentine, 1909 Peruvian, and a VZ24. The Argentine and VZ24 were barreled before my purchase and I can't vouch for them The other two had a slight radius on the ID to the first thread. The first thread does come to the radius. The small vee groove at the shoulder allows the barrel to seat on the H or C ring and also touch the shoulder.
I think if you have the opportunity to try it my way, you will see that it works. I use a Trav a Dial on the carriage and can stop the carriage within .005". The advantage of threading slow.
Not a good photo, but I think you can see what I'm speaking of.

I have a lot of photos, but I normally don't photograph that part as I've never seen a use for it, to this point.

Never touched a gun part. Leave that to the experts.
But have threaded thousands of sucker rod connections at 10tpi.
Leblonds sound like they want to come apart at over 300 rpms when
you compound the feed so that's the only limitation on speed.
16 tpi or finer go to 500 to a shoulder.
OD or ID.
All depends what you get used to.
Once you try the higher speeds you won't go back.

Won't get into arguments on threading speed. For manual lathes I'd say you that my 10EE could thread at a tremendous speed as it has ELSR. Electric Leadscrew Reverse. It stops within a .001" ea. time. Crank the cross slide back to a preset stop and hit the ELSR lever. it fast travels back to your preset setting. Dial the cross slide screw in until the preset stop stops it and make your compound adjustment. You do not fool with your half nut.

My Warner HSS tool holder uses inserts that are vertical and are not the lay down type. The insert is .125 wide and the bottom of the vee can be .0625 from the shoulder, but remember angle of the vee from the thread bottom is angled to the face of the receiver. You will not have an .0625 flat. Hopefully this makes sense. I'm not against a thread relief, I just do it differently.

quote:

Originally posted by dpcd:
I think I will stick to slower speeds on the $300 barrel blanks. One slip or failure to disengage the half nut will result in a major f up. I mean disaster.

I completely understand and I'm not a speed demon. In the olden days I thought speed was required and did hit a couple shoulders. Fortunately it didn't scrap the barrels, but reindicating the barrel, picking up the old threads, and recutting the shoulder is a real time eater.

Jeff,

What were the issues with this unit?

The price is sure attractive...

quote:

Originally posted by jeffeosso:
I had this, about 20 years ago .. thought it was a good idea, until i got it
http://www.grizzly.com/product...mbo-Lathe-Mill/G9729

it is great for nothing, a decent lathe, and everything else is meh ...

dpcd,
Only talking about the capabilities of of my Monarch 10EE. It is too long in the headstock and too short between centers(20") to chamber barrels. It is a modern lathe??, made in 1956. I do my barrel work on my Clausing 6913 14X48 lathe. It is a 1972 model. It is just a good regular lathe.
I'm certainly not disagreeing with you as I think a lot of your knowledge in your post.

I was looking at the smitty granite I-max 1340. the speed is 0-2800. It weights 790 something. I really just plan on doing hobby jobs for myself. I can understand needing 2 machine if I was going to try and really make money at it but I'm not that kind of good. The threading of barrels would be for suppressors or brakes. I would love to be able to replace barrels but don't know enough. This shop is to keep me busy and out of my wife's hair. In other word to ensure my good health If need be I'll buy 2 machines dpcd could you look at the spec on the machine and tell me if it is worth it for my uses.

Could you not buy a real mill and lathe for the price? I understand what you are wanting to do, but I think you will be real disappointed going this way.

Okay I'm listening. What brand and models do you recommend. I don't have 3 phase as this is a hobby shop not wired for all that. 220 is the best I can do. Also this is a hobby so want to keep the cost down as much as possible.

I did look at the grizzly 12-36 gunsmithing lathe and a 8.5x29 power feed mill total would be 6k plus another 2k acc. is this a good est. and what should I look to buy first as far as cutters and acc.

Don't let 3 phase throw you for a loop. I do not have 3phase into my shop, but use rotary phase converters and VFDs to provide 3 phase.You can buy a real lathe and mill for no more than $6000 and yes, you will need some tooling. It doesn't appear that the tooling offered by Smithy would be any different than what you should get when buying used.
It appears to me that you need to learn a lot more before spending money.

Dpcd
If you ever go to threading inserts I
suggest going to the specific tpi topping
off inserts.
They last forever and allow you to get
as close to the shoulder as possible. They last
longer because the nose won't be as sharp
as a general purpose insert is.
If you buy a Kennametal top notch holder I might be able to
help you out
As to the OP. There are a lot of deals to be made in the used
market. You can get around the three phase problem, but lifting
something that needs a forklift might be a problem
The magazine "Home Shop Mashinist" has a lot of articles
about bringing an old machine back to life.

Check The Practical Machinest forum.

There are certainly deals out there on the used market. Deals are made better since its a buyers market, at least it was last year when I got these two machines for $5250 including a bunch of tooling.

A 1340 Bermingham lathe and Bermingham 9x49 knee mill. Sure, its not American iron, but both have been working very well for me.

In the picture of the lathe I turned the 27" barrel unsupported in the middle without it chattering. The variance from one end to the other was .001". Not bad.

dpcd
Do you have any experience or know someone that does on the $2795.00 lathe? The reason I am asking is I have been looking in the catalog and wondering how it would be.