ideas on how to match a contour on manual lathe

[Shawnba67]

I have a barrel that i need to put on a diet Im thinking of going to the sedero contour. I would like ideas on how to come close to matching the gentle curve of the first neck down portion, now heres the fly in the ointment I do not have a sedero to measure from or i would just measure the curve every .050 or so and make little steps then attack with that lathe file i love so much lol thanks for any ideas
I do have some regular sporter barrels from various 700's is the curve portion of the neck down relatively the same "curve" just with different diameters?
SECONDARY question if my above ideas fail will a heavy or medium palma fit into a sedero inlet stock??? thanks again

 

[B Nettesheim]

A taper attachment would be your best friend!!

 

[Shawnba67]

A taper attachment would be your best friend!!

Well i cant afford/wont spend it, but how would it help on a gentle curve? for the easy part i just offset the tail or Have been known to step down an entire length i set up a yard stick and an indicator and go in .002 or whatever every quarter inch works ok in a pinch then you gotta file like a madman lol

 

[hammerjack]

A light palma would be pretty close.

 

[Shawnba67]

Ok well i continued my search and found an online article in rifleshooter mag that the guy was doing this exact thing and had the steps written down so i just copied them. Easy peasy now well except for all that filing to come

 

[RemingtonAI]

Why not just calculate the offset of the tail stock in order to cut the desired taper?

 

[B Nettesheim]

You could use your compound too for the tapered part it would just take a while. I don't know what you mean by the curved part, maybe a radius??

 

[Nvreloader]

I have used a tool like this when copying contours,
and seems to work well, comes in 6" and 10" lengths.

https://www.woodcraft.com/products/...kzh5NcnYgl-zLqFUjdxVNYHCq0_em8vk3ihoCF6Tw_wcB

I had to free hand the bbl cutting, but produced results that were very close to what was needed.

HTH,

Tia,
Don

 

[Shawnba67]

Why not just calculate the offset of the tail stock in order to cut the desired taper?

because the step down from shank to the tapered part of the barrel is not a taper its a radius curve. For clarification im talking about the 3'' transition from the barrel shank to the thinner portion of barrel

 

[hpshooter]

" For clarification im talking about the 3'' transition from the barrel shank to the thinner portion of barrel"

Use a ball turning tool in reverse to cut a concave radius assuming the radius is constant.

Lots of simple design ball turning tools on the net. Easy to fab from the scrap box.

Or, a series of HSS profiling tools feed perpendicular to the stock as you would do with a parting tool.

Not for the faint of heart, but my grandfather, who was a machinist from the end of WWI until the mid 60's, would Slowly cut radiuses (on steel stock) with a round nose HSS tool welded to an appropriate sized wood lathe gouge using a wood lathe tool rest in place of his tool post.

 

[TRA]

You can always freehand it. Those that have spent years standing at a manual lathe can get pretty good at it. They go slow, get it real close roughing it, then work it down with files and abrasives. The best plan is have someone with the proper equipment to do it. In the pre CNC days, they would use tracer lathes. Not many of them around or functional these days. Most were hydraulic, some home built ones worked similar to a taper attachment. T

" For clarification im talking about the 3'' transition from the barrel shank to the thinner portion of barrel"

Use a ball turning tool in reverse to cut a concave radius assuming the radius is constant.

Lots of simple design ball turning tools on the net. Easy to fab from the scrap box.

Or, a series of HSS profiling tools feed perpendicular to the stock as you would do with a parting tool.

Not for the faint of heart, but my grandfather, who was a machinist from the end of WWI until the mid 60's, would Slowly cut radiuses (on steel stock) with a round nose HSS tool welded to an appropriate sized wood lathe gouge using a wood lathe tool rest in place of his tool post.

Freehand it. Takes practice but with patience and a good template it's doable and cost's nothing but time. If you finish it with a flap wheel in a die grinder, it will take longer to clean your lathe back up. It will make a mess and is brutal on a good lathe.

 

[hpshooter]

"You can always freehand it."
Have done a couple 2" cascables on cannon barrels this way when making a non to scale "noise maker".

Kids Etch-A-Sketch is good practice for left-right hand co-ordination to make curves and circles.

Lots of options to solve most problems just pick the one you like best.

 

[Riesel]

I have had pretty good luck turning this area of the barrel in the metal lathe by freehanding. Move barrel to wood lathe that has had the pulleys changed out to run somewhere around 300 rpm as I recall. center barrel using a live center on the tail stock (MT1) and center in the head stock plate
using the four way chuck. Get after it with an angle grinder and flap disc of various grit. Makes a hell of a mess but works nicely. Used this same method
to put a nice finish, not hi-gloss, on the barrel. Usually finish out with some sort of buffing compound. Headstock portion gets removed during threading
I usually have one of those muzzle saver brass tips inserted. Just an idea, hope it helps.

 

[MDSpencer]

After all this your recutting the crown?

 

[Will Henry]

Tom Burgess described it to me as the "etch-a-sketch" method. Short of making up a copier for your lathe, it is as good a way as any. Maybe practice a little on scrap first. Once a person gets used to co-ordinating the feeds, it can work out pretty well. WH

 

[Intheshop]

We reproduce ball ends and machine handles on equipment resto's every couple weeks.I just freehand them....dang quickly.Get some scrap and make some tulip shaped handles.

 

[Intheshop]

Turned 5,1 1/4" tulip with ball ends this a.m.Took about an hr.They fit into the ends of some decorative pipe rails.Just freehanded them.Critical measures are all,spot on....radius ends up being a,connect the dot between major/minor diameters.Blend with a file.They're so close,I can't tell one from another.It just takes practice.Good luck with your project.