Making a Spider for the lathe

mickri said:
would also like to have dead center that fits precisely on the bore of the spider.
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Just curious about the intended use of a center on the outboard end of the spindle.
 
No current intended use. Seems like it might be handy to have if I needed to turn something between centers that was too long to fit between a dead center in the headstock and a live center in the tailstock. Easier to do now before I permanently install the spider on the spindle.
 
That’s a interesting idea. I would go with hardening it just in case. However the problem I see with that is it might get deformed in the process and then you wouldn’t get the precision you’re shooting for. What idea do you have on attaching it to your spider? Would external threads on the dead center and internal threads on the spider be okay? I would hate for it to back out and tear something up or worse.
I want to learn how to thread and chamber my own barrels at some point and was thinking that working between centers would be a easier setup and give better results. Your dead center in the spider might come in real handy for that. Darn good idea. Let us know how it turns out.
 
My lathe came with a Craftsman tool post grinder (wrong term??) that mounts on the compound. I can always grind the pointy end if I need to.

Gunsmith Rod Henrickson who goes by Spearchucker on many forums posted on PM how he threads and chambers barrels between centers. I have several barrel jobs on my to do list and will follow his method. Chamber reaming between centres (practicalmachinist.com)
 
mickri said:
My lathe came with a Craftsman tool post grinder (wrong term??) that mounts on the compound. I can always grind the pointy end if I need to.

Gunsmith Rod Henrickson who goes by Spearchucker on many forums posted on PM how he threads and chambers barrels between centers. I have several barrel jobs on my to do list and will follow his method. Chamber reaming between centres (practicalmachinist.com)
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Between centers is the only way to get true concentricity.
Just make sure the headstock and tailstock are aligned in both X and Y.
 
I’ve seen countless videos where the gunsmith tells how important concentricity is and then he sticks a grizzly rod in the barrel and adjusts the barrel with the chuck and spider. Most mention how it can take 30-45 minutes to get it right and that their way is superior. It doesn’t make since to me for them to do all of that. The first thing I learned about concentricity was that between centers is best. I’ve never done any barrels but it seems that it would be easier and better to work between centers. I’m glad to hear that people are doing it that way. I should mention that in this day and age people shouldn’t call that fella a spear chucker. We use to say stuff like that here in the south but colored folk aren’t typically treated like that anymore. Different times
 
Spearchucker is what he named himself......
 
His actual online name which he chose is spearchucker30x378. He is up in Canada and was trained in Colorado I believe.

I totally agree. It makes no sense to me to go through all of the trouble dialing in rods sticking out of both ends of the barrel. My understanding of the theory is that dead and live centers may not be true to the bore where as a dialed in rod is true to the bore. When I get to doing my barrels I will do them between centers. I specifically got a 12x36 lathe so I could chamber barrels between centers.
 
The discussion on chambering methods has been going on for many moons. There is more than one way to cut a chamber well on a lathe. Results depend as much on how well the operator understands and applies the procedure as on the procedure itself.
Basic assumptions about how straight the bore is and what part of the bore to dial in can vary. Some take great pains to dial in a bore simply because it suits their limited equipment and they enjoy doing it that way.
 
For the people competing at the highest levels the mental aspect of believing that you have the absolute best equipment possible has a relationship to how well you will do. Any doubt about your rifle will be reflected in how well you shoot. If dialing in a barrel with rods gives you more confidence in your rifle's accuracy you will shoot better. If you think chambering between centers achieves a better result than dialing in rods than that is what you should do. For us mere mortals that want a rifle that will shoot minute of deer, coyote or whatever it probably doesn't matter what method you use to chamber a barrel along as you do a decent job.

Chambering between centers was a practical consideration for me. Lathes with a large enough spindle bore to chamber with rods through the headstock were more than I could afford. The lathes that I could afford invariably had a 3/4" spindle bore. So I looked for at least 30" between centers and ended up with a Craftsman 12x36. I first thought about a dead center in the outboard end of the spindle to provide the extra length needed to chamber between centers when all I was finding was lathes with a between centers length of around 22". In my travels around the web I ran across people chambering barrels on mini lathes. Even found one guy who reamed the spindle on his mini lathe out to either 13/16 or 7/8. He was a master machinist who worked at the Lawrence Livermore Labs with all of the computer technology to do finite analysis of a bored out spindle.

This dead center project is on the back burner until I get done with my header project.
 
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