small lathes and cutting treads
- Thread starter Garyg
- Start date
Blastattack
CGN Ultra frequent flyer
- Location
- Winnipeg MB
You don't generally single point thread such tiny threads. You would be best off turning the shank and thread using a die.
This above, as often as not. For a guy that does not or will not take the practice time to learn how to grind the tools and set it all up, a die in a holder is a great option. Another option is a die head. They are used on old school production lathes, lots on Ebay. Bunch of coin though. Look up Geometric Die Heads.
Really, unless there is a real good reason, you are better off buying screws that small. A commerciallly made screw is likely to have a rolled thread, which will make it stronger, as well as being (often) atougher material than the material you are likely to want to turn on the lathe.
But it comes down to practice and care in setting up. I know guys that use a binocular microscope a lot when they are making parts on their Sherline lathes. With enough magnification, it becomes just about the same as any other thread.
Cheers
Trev
Brownell's out of the States is the easiest. Often the cheapest, too. IIRC Brownell's also sells an assortment of scope mount type screws and blank screws that can be cut to length and machined to fit (the head is oversize and unfinished). No export restrictions on tools. Dunno if they will process the order on line or not. Best bet is to phone and speak to the real live person.
But pretty much any Machine Tool Supplier can get you taps and dies in any thread diameter-pitch combination you want, eventually, and for enough money.
Where are you? It will determine who is closest, as far as suppliers goes.
Most gun screws are a finer thread than the 'standard' series pitches. Not going to get them at the CTire or Home Depot type outfits.
Cheers
Trev
But pretty much any Machine Tool Supplier can get you taps and dies in any thread diameter-pitch combination you want, eventually, and for enough money.
Where are you? It will determine who is closest, as far as suppliers goes.
Most gun screws are a finer thread than the 'standard' series pitches. Not going to get them at the CTire or Home Depot type outfits.
Cheers
Trev
I've single point threaded thousands of 2-56 and some 0-80's on hardgine hlv-h and my cyclematic 618evs(hlv-h copy).
Mainly stainless(304 , 316) threads, gauged to spec. With the right tools and experience anything can be made.
Did some 4-40's and such on my 14" lathe, they're just parts.
I don't use dies for anything except the really odd mod on something that can't be put in a lathe, which have been maybe 3-4 times in 10yrs.
Mainly stainless(304 , 316) threads, gauged to spec. With the right tools and experience anything can be made.
Did some 4-40's and such on my 14" lathe, they're just parts.
I don't use dies for anything except the really odd mod on something that can't be put in a lathe, which have been maybe 3-4 times in 10yrs.
Some sizes can be had from regular machine tool shops like KBC here in Canada or places like Enco in the US that does a lot of mail order. But the finer sizes like 4-48, 6-48 and some others commonly found in gun work is best gotten from Brownells as suggested.
And such sizes are pretty tough to machine. Not to mention that you won't machine the threaded holes in a receiver or other such female threading option. You need taps for those.
One option for a lathe to aid in aligning your dies for making custom screws is this pair of tools I made about 25 years ago. It wasn't my idea either. I got it from Guy Lautard's "Machinist's Bedside Reader". A great set of books for anyone that enjoys metal working.
This is the idea. You just need to make it to fit the size of your round dies. This is the larger of the two. The other one is done from a slug of 1" steel with a recess to accept the smaller 13/16 dies that are used for down to 0-80 threads. The second picture shows how it's used. The handles are short enough to spin over the bed. You don't run this under power unless you're tired of living. Hand turned only!
The idea is that it lines up the die with the stub to be threaded in a "close enough" manner. And for all but the most demanding need for centering the threads this is good enough.
And such sizes are pretty tough to machine. Not to mention that you won't machine the threaded holes in a receiver or other such female threading option. You need taps for those.
One option for a lathe to aid in aligning your dies for making custom screws is this pair of tools I made about 25 years ago. It wasn't my idea either. I got it from Guy Lautard's "Machinist's Bedside Reader". A great set of books for anyone that enjoys metal working.
This is the idea. You just need to make it to fit the size of your round dies. This is the larger of the two. The other one is done from a slug of 1" steel with a recess to accept the smaller 13/16 dies that are used for down to 0-80 threads. The second picture shows how it's used. The handles are short enough to spin over the bed. You don't run this under power unless you're tired of living. Hand turned only!
The idea is that it lines up the die with the stub to be threaded in a "close enough" manner. And for all but the most demanding need for centering the threads this is good enough.
Just be sure to check that the tail stock axis is in line with the headstock. And that's not a bad thing to check and adjust anyway. Makes for tail stock drilling that's a lot more accurate and less surprises of all sorts.
It's easy to do. Stick a stub of something into the chuck and turn it to a size near to 1/2 or 3/8 diameter. It's not really that critical as you'll seen in a second.
Now using your handy dandy tool post mounted dial gauge.... er..... you DO have a TPMDG don't you? If not see pictures below for one VERY handy lathe gizmo. The tip is set so it aligns with the center of the head stock axis by eye. Just zero it to the little stub or center mark left by a facing cut on some scrap or your workpiece by eye and it's good enough.
ANYWAY... to check your tail post for on axis you chuck up a stub of round stock and turn it so you're not including any jaw runout. Turn it to a size which you can match with a stub in your drill chuck in the tail stock. A piece of 1/2 or 3/8 O-1 drill rod works well. Or you can use the parallel portion of a fixed center and turn the scrap to a size close to that size. Measure and take note of any size difference between the stub turned in the chuck and the stub or center in the tail stock. Now run your dial guage in and pick up a measure off the stub in the chuck. Move along the bed to the stub or center in the tail stock and note the difference. Now with a touch of math and knowing the difference in size between the two measuring points it's easy to see if your tail stock is aligned or not.
This is mostly for lathes that have a tail stock which can be offset to use for turning tapers. If the small machines don't have this then you're mostly testing for any error that you'll then need to take into account when doing anything fussy and demanding for accuracy. It could also result in the handy threading tool not cutting all that axially.... which was why we checked for this in the first place to go along with this thread..... I got wandering again, didn't I.....
Anyhow, here's a couple of pictures of the dial guage mount that fits into my four position tool post. Use the idea to suit your own machine. If you use a lantern style you may want to add a foot screw so it can be adjusted and reset's to the same riding position each time in the lantern and saddle key. This one is pretty crude. I made it in a hurry. But it's worked so well that I've never bothered to make up anything more fancy. It's just there for all the times I need it. And it gets used a lot. Far more than my magnetic base. And for zeroing work in the independent four jaw this trick really is the way to go.
It's easy to do. Stick a stub of something into the chuck and turn it to a size near to 1/2 or 3/8 diameter. It's not really that critical as you'll seen in a second.
Now using your handy dandy tool post mounted dial gauge.... er..... you DO have a TPMDG don't you? If not see pictures below for one VERY handy lathe gizmo. The tip is set so it aligns with the center of the head stock axis by eye. Just zero it to the little stub or center mark left by a facing cut on some scrap or your workpiece by eye and it's good enough.
ANYWAY... to check your tail post for on axis you chuck up a stub of round stock and turn it so you're not including any jaw runout. Turn it to a size which you can match with a stub in your drill chuck in the tail stock. A piece of 1/2 or 3/8 O-1 drill rod works well. Or you can use the parallel portion of a fixed center and turn the scrap to a size close to that size. Measure and take note of any size difference between the stub turned in the chuck and the stub or center in the tail stock. Now run your dial guage in and pick up a measure off the stub in the chuck. Move along the bed to the stub or center in the tail stock and note the difference. Now with a touch of math and knowing the difference in size between the two measuring points it's easy to see if your tail stock is aligned or not.
This is mostly for lathes that have a tail stock which can be offset to use for turning tapers. If the small machines don't have this then you're mostly testing for any error that you'll then need to take into account when doing anything fussy and demanding for accuracy. It could also result in the handy threading tool not cutting all that axially.... which was why we checked for this in the first place to go along with this thread..... I got wandering again, didn't I.....
Anyhow, here's a couple of pictures of the dial guage mount that fits into my four position tool post. Use the idea to suit your own machine. If you use a lantern style you may want to add a foot screw so it can be adjusted and reset's to the same riding position each time in the lantern and saddle key. This one is pretty crude. I made it in a hurry. But it's worked so well that I've never bothered to make up anything more fancy. It's just there for all the times I need it. And it gets used a lot. Far more than my magnetic base. And for zeroing work in the independent four jaw this trick really is the way to go.
I think to single point a screw as small as #2 or #4 you would need to support the tail end with a center in the tailstock or perhaps a close fitting hole in a piece of shafting mounted in the drill chuck in the tail stock. You would also need some way of preventing the work from bending and riding up over the lathe bit. Following up on the hollow shaft instead of a center, possibly if you advanced that shaft by hand to follow the cutting point might support the work
cheers mooncoon
cheers mooncoon
Most of the 0-80, 2-56 single point threading I did was 3-4xD, no end support needed, just gotta have the right machine and tools. Generally all with carbide too. I always found that dies make really poor sh*tty looking threads... and they do...
All things are proportional.
All things are proportional.
