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Phxguy66
04-12-2011, 04:18 AM
Hi all-
I've been a member for awhile, and been lurking closely. One question I've been dying to ask (and the answer to which I've so far been unable to locate by searching), is this:
For all of you that thread Savage barrels, do you use a v-bit, or is there a special tool for this particular thread? You see, I recently got a great deal on a 13x36 gunsmith lathe, and I would like to start messing around with chambering and threading some barrels, just as a hobby.
Any input and feedback would be greatly appreciated, just please take it easy on me...:)

frwillia
04-12-2011, 06:19 AM
Hi all-
I've been a member for awhile, and been lurking closely. One question I've been dying to ask (and the answer to which I've so far been unable to locate by searching), is this:
For all of you that thread Savage barrels, do you use a v-bit, or is there a special tool for this particular thread? You see, I recently got a great deal on a 13x36 gunsmith lathe, and I would like to start messing around with chambering and threading some barrels, just as a hobby.
Any input and feedback would be greatly appreciated, just please take it easy on me...:)

All the Savages I've done were 20 tpi with normal 60 degree thread profile. I use a threading tool bit to cut them (see picture), not a V-bit turning tool. I use a good high sulfur cutting oil for threading.

I'd highly recommend that you get Richard Franklin's DVD Metal Working for a Rifle Smith, Gordy Gritter's DVDs, and Hinnant's excellent book. You will need some tooling, much of which you can make with a lathe and drill press. Not sure what your machining skills are, but making some tooling will give you a chance to learn if you are just starting out.

Finally, do a search on this forum and the Practical Machinist Gunsmithing forum on "chambering" and another on "aligning". With a bit of luck you will find enough information that you can cut and paste it into an MS-Word document and make your own book on chambering, tools, alignment of blanks in the head stock, tooling (reamer pusher for example). There is a ton of information on the two forums - you will be able to sort out what makes sense and what doesn't after a while. 15 or 20 hours doing this sort of research combined with the videos and making some tooling will do a lot to get you up to speed.

Fitch

PS: I ended up compiling a reference that's over 200 pages from the forums mentioned. Much of the benefit comes from compiling your own.

frw
http://i22.photobucket.com/albums/b336/frwillia/readytotocutthreads-A-RS-1.jpg

B.Johnson
04-13-2011, 09:17 PM
On center fire benchrest I have a photo under Savage bolt head on a Rem. bolt. It is a grinding jig for grinding high speed steel cutting bit's for threading. You cannot grind a improper bit with this tool. Forget tungsten insert's for threading a barrel. Your lathe is not rigid enough for insert's. Use a proper ground bit, a dedicated tool post for your lathe, run the machine in reverse, and threading becomes just another turning operation. I forgot to mention! to thread in reverse the cutting bit must be upside down, and of course on center

frwillia
04-13-2011, 09:56 PM
On center fire benchrest I have a photo under Savage bolt head on a Rem. bolt. It is a grinding jig for grinding high speed steel cutting bit's for threading. You cannot grind a improper bit with this tool. Did you make that sharpening jig? If so, you you have a sketch of it with dimensions you would be willing to share?

Ah, I found it here: http://www.gadgetbuilder.com/ThreadingTools.html I think I also have Martin Cleeve's book someplace ...

Thanks
Fitch

B.Johnson
04-13-2011, 10:37 PM
frwillia: Follow Martin Cleeve's direction's. That tool is simple to make, and well worth the time. You will need a proper grinding toolrest as shown in his direction's. That book is the best I have found on threading. Follow his simple direction's on measuring using the three wire method. You will be surprized at the quality of thread you will be producing. As I said, it will become just another turning operation.

alinwa
04-14-2011, 02:55 AM
And now for something completely different...... ;)

I've always had less problem with grinding to shape than with burning the fine tip of the bit JUUUSST as it gets right. Just a split second too long and BOOM, you gotta' start all over....

Sharpening jigs are cool. I have several and have made several for different applications but the best investment I've made for grinding nice HSS bits is an actual water drip tool bit grinder. It's a cheapo import, it's messy but effective, the key item being the hollow wheels where you feed water to the inside surface and it slings thru the wheel and keeps the bit cool as you grind it. Right now I rarely use a jig of any sort but by using the water cooled wheels just like using a regular wheel grinder or even a sanding disc or belt I can keep the toolbit on the surface of the wheel as long as I want without burning it.

Ain't nothin' quite like slicing metal off with a really sharp bit.

I put the $200.00 investment in the water cooled grinder right up there at the top of the "must have" short list of tooling for small lathes using high speed steel tooling.

al

frwillia
04-14-2011, 06:13 AM
frwillia: Follow Martin Cleeve's direction's. That tool is simple to make, and well worth the time. You will need a proper grinding toolrest as shown in his direction's. That book is the best I have found on threading. Follow his simple direction's on measuring using the three wire method. You will be surprized at the quality of thread you will be producing. As I said, it will become just another turning operation.

Thanks. I love that book. I've read it a couple of times but it was a long time ago. I completely forgot about that tool. I think I'm getting age induced divots in my cranial media. I used an HSS tool to cut the square threads on the '03 Springfield I rebarreled not too long ago. I might as well try one for threading on the next one I do that has threads.

As fate would have it the barrel in the lathe is for a POS Charles Daley .22 Hornet that is based on a rimfire action that I'm rebarreling for a friend. But the next one is either a Savage, CZ 527, or '53 Winchester.

Fitch

frwillia
04-14-2011, 06:36 AM
And now for something completely different...... ;)

I've always had less problem with grinding to shape than with burning the fine tip of the bit JUUUSST as it gets right. Just a split second too long and BOOM, you gotta' start all over....

<snip>

I put the $200.00 investment in the water cooled grinder right up there at the top of the "must have" short list of tooling for small lathes using high speed steel tooling.

al

I agree with everything you said about HSS bits I use them most of the time except for threading, and that may change as well.

Anyway, I use an icecube. Literally. When I have to grind a new HSS tool, or a chisel, or some other tool, I use an icecube held on the tool against the grinding wheel. The icecube grinds away layering the wheel with almost freezing water. I grind most lathe bits free hand - took me a while to get comfortable with holding the cube and bit, but once I did, no more over heated tools. Don't get me wrong, I think the water drip grinder is the better solution, but there is an ice cube option.

I have an old Sears grinder - made some big rests for it, take it outside - sprays crap everyplace, but I can grind a bit really fast with no trace of overheating. The tool rests are all rusty but it still works great.

Fitch

jackie schmidt
04-14-2011, 08:06 AM
Fitch, I could not help but notice. If you are cutting 20 tpi, the flat on the end should be about .007, looks like yours is about 4 times that amount.

For those that do not know, a proper 60 degree threading tool has a flat that is 1/8 the pitch. For instance, if you are cutting a 8 tpi, the pitch is .125. The flat would be a tad over .015 inch.........jackie

frwillia
04-14-2011, 12:47 PM
Fitch, I could not help but notice. If you are cutting 20 tpi, the flat on the end should be about .007, looks like yours is about 4 times that amount.

For those that do not know, a proper 60 degree threading tool has a flat that is 1/8 the pitch. For instance, if you are cutting a 8 tpi, the pitch is .125. The flat would be a tad over .015 inch.........jackie

Good eye. It's damaged. Notice the one pointed more toward the camera. I rotated the insert before I did the threading. That was the last tip on that insert.

Fitch

alinwa
04-14-2011, 06:01 PM
friggin' ICE cube......awesome.

you oughtta' see the Rube Goldberg setup on my three older grinders and sanders from prior to the tool grinder!! :)

I drilled holes in my support plates and made pivoting spring loaded drivers couple with a water drip system so's I could jig a tool bit up and walk away, just let it slowly grind while I worked elsewhere....

I tried air cooling....

friggin' ICECUBE

LOVE it

LOL

al