Lathe Spiders

[Jud96]

Delete if not allowed.


Hi guys. I’m kicking around the idea of manufacturing lathe spiders for D1-4, D1-5, and D1-6 spindles. They will be one piece made out of steel, no backing plate required, threaded 3/8-24 for the set screws, they will be 1-7/8” thick to stay close to the spindle for rigidity and keep the overall length of the spindle shorter, and the through hole will be 2-1/4” to allow room for pivoting V-blocks but minimizing the amount the set screw threads are exposed to aid in rigidity.

I would also like to do the outboard side, but that’s tricky with the different diameter spindles and trying to hold a tight slip fit.

Does anyone have interest in these, or think it would be worth while? Any opinions and input is always appreciated. I looked around and there’s not much commonly available that’s a high quality part. I haven’t crunched the exact numbers, I’d guestimate they will be around $400-500 each and that’s with the cam lock pins and ready to be mounted to your lathe.

Thanks!

Pictures below are of a 7” diameter D1-6 spider I worked on this past weekend and will finish soon.

 

[DR_2297]

Be mindful that most of the Chinese and Taiwan “gunsmith” lathes with outboard spiders incorporated into the spindle are metric threads. My spindle nose spider therefore has metric jack screws so I only have to use one Allen wrench for setup and indication.

 

[marazzi59]

Might I add an idea for better barrel alignment?

 

[Judd]

I gained 2” by purchasing the one that Grizzly sells…I am at 22” for the 4 jaw and can do a 20” barrel in the spider. I don’t use it unless I have too, I much prefer the 4 jaw, likely because I have more time with the 4 jaw. Price wise, pretty tough to beat that Grizzly.

Good luck.

 

[Jud96]

Might I add an idea for better barrel alignment?

Yeah of course

 

[marazzi59]

I get annoyed with people who post things that take the post off topic or in a different direction, I figured I should ask.

 

[marazzi59]

I machined aluminum pucks with a radius that matches the barrel od on one side. On the opposite side in the center I used a ball nose endmill. On the end of the adjustment screws I installed a ball bearing the same diameter of the ball nose mill. This allows the barrel to pivot much easier when I make an adjustment on the opposing spider. I personally don't pay attention to the muzzle end when indicating the chamber end. I just indicate on 2 spots on the chamber end

 

[WSnyder]

Offer a plain backed version so one could mount it on a backing plate for other spindle types. Basically a larger heavier better quality than the cheap Grizzly Bald Eagle spider. I did one for myself basically like your proposal but put it on an L00 backing plate.

 

[WSnyder]

I machined aluminum pucks with a radius that matches the barrel od on one side.

He stated he was going to make them with pivoting V-Blocks.

and the through hole will be 2-1/4” to allow room for pivoting V-blocks but minimizing the amount the set screw threads are exposed to aid in rigidity.

 

[marazzi59]

I tried uploading a video to show it but file is to big

 

[marazzi59]

Wasn't sure or couldn't visualize the v block. Thought maybe the system I use could be easier

 

[Jud96]

Wasn't sure or couldn't visualize the v block. Thought maybe the system I use could be easier

The V-blocks work just like your radius blocks, but work with basically any size barrel from 0.600-1.350”.

The radius blocks work too, I just prefer the V-blocks

 

[Jud96]

Offer a plain backed version so one could mount it on a backing plate for other spindle types. Basically a larger heavier better quality than the cheap Grizzly Bald Eagle spider. I did one for myself basically like your proposal but put it on an L00 backing plate.

That’s a good idea too. It definitely wouldn’t be as cheap as Grizzly’s, but it could be adapter to any backplate

 

[Sray53TXTN]

For comparrison
PTG has the Kiff Version

Kiff Spider, Six Point Truing Jig $324.00​

Kiff Spider, Six Point Truing Jig-PTG-1050

www.pacifictoolandgauge.com

 

[Machinist John]

Made this one 10 years ago, Swiveling pads are copper.

 

[Kiwishooter]

I made this one many years ago, it's D1-6, only 2" thick and uses 1/2 unf screws

 

[Jud96]

I made this one many years ago, it's D1-6, only 2" thick and uses 1/2 unf screws

View attachment 1711460

That’s nice

 

[tobnpr]

For comparrison
PTG has the Kiff Version

Kiff Spider, Six Point Truing Jig $324.00​

Kiff Spider, Six Point Truing Jig-PTG-1050

www.pacifictoolandgauge.com

I like the idea of the six-screw spider. Many times would've been helpful when the movement/pivot point I needed was between screws on the 4 point spiders.

I'm going to make new inboard/outboard ones to see if it speeds up indicating.

 

[BuffaloBill]

This is a one-piece D1-6 I made a few years ago, using 1/2-20 screws, 1/4” balls, etc. I’ve since laser engraved more attractive numbering……



Edit to add: I chose to use only 4 of the 6 attachment pins, as this provided unobstructed areas for the 4 adjustment screws. I shortened the Bondhus T-wrenches so they’d be more comfortable to turn at the bottom between the lathe ways.

 

[WesG260]

I saved myself the trouble ... bought cast iron D-4 backing plates and attached aluminum sleeves to them.

Short one for barrels. Tail end is a steel sleeve with a split clamp to attach to the spindle.

Long one for actions. 2 sets of rear holes, SA and LA. So far has worked out for 700's, and 70's. Not much else it likely needs to fit ... maybe a Savage? But then again ... why? ;-)

Of course, I wasted who knows how many hours fixing a Ruger M-77 ...