Then Came The Spider

[StraightPipes]

Time to build new fixtures. Spiders on both sides are going to be needed to complete the retro fit..............

The screws need to be "tipped" in something. Brass, aluminum, copper? Copper seems the logical choice in my opinion but the range of "tool plastic" interests me. The only thing that causes me to think about the resins is they might move around or relax when they get warmed up. Delrin or UHMW urethane might work, but will they change dimension or SLIP after the time is spent dialing in to .0002 or better?

 

[STS]

Use brass. You won't regret it.

 

[Erik Cortina]

I used aluminum, so far so good.

 

[Rustystud]

Greg Tannel's action truing jig has alluminum insert on the ends of the screws. I have found over time the tips have to be replaced. They have to be made or purchased. I use .500" x 20 tpi screws turn the ends down and use .250" copper pipe caps. I turn a slight taper and swage the caps on to the screws. They are small enough to go in and out of the threaded holes in the spider. They are easily replaceable and inexpensive. They also don't violate the spirit of Mr. Tannels products.
Nat Lambeth

 

[Preacher]

I just drilled and tapped the ends of the screws to accept nylon screws..
They havn't worn out yet 'O)

 

[StraightPipes]

Nat, I like your idea. Ive used the .500x20 screws but drilled a hole in the end and inserted a .250 piece of brass rod. You use a "dog point"on your cap idea.

Preacher, nylon? Nylon maintains dimension while chambering? I like the idea. If you spin a barrel, there is "0" damage. Maybe Im over-thinking the idea of using a plastic. You care to explain , defend using nylon?

 

[Preacher]

Just 1/4 20 nylon bolts from the local hardware store with the heads cut off after they are screwed tight into the bolts...
I round them off a little with my sander.....
They don't distort because there is not a ton of pressure on them, just enough to keep it where I put it..

 

[StraightPipes]

Well Preacher, Im gonna try it.

 

[butchlambert]

I use these on both sides as I use 2 spiders.



Gene Bukys did some for me and I copy them now. Copper ground rod in the setscrews. I personally think brass is too hard.

 

[StraightPipes]

Hello Butch, copper makes sense. Your saying that you make them these days? How long are they?

 

[butchlambert]

I only make them for myself. I believe they are around 2". You can buy the at McMaster Carr. I chose fine thread as it allows small adjustments a little easier.

 

[jscandale]

I love mcmaster and buy a lot of stiff from them. They just came out with a nifty iPad app. It's very nice, very comprehensive.

JS

 

[StraightPipes]

Well Butch, you got me there! You caught me being a lazy old fart!!!!!! I cant buy them with "copper" tips, but I have made them with brass tips. .500x20tpi works for screws. Looks like your doing that with .250 copper ground rod.

McMaster Carr as well as MSC Direct keep things in motion for sure.

 

[StraightPipes]

I think this dam spider BIT me. There is way too much hardware available today.

Now, how about some "SWIVEL PADS".......... Not fine thread, but 1/2-13 with a DELRIN pad .400 in diameter which swivels. Maybe Delrin is too slick?

Any REAL advantage to build spiders with "ALL" the contact points to swivel?

 

[butchlambert]

Not if your barrel pivots on the copper points. Remember I have spiders on both ends.

 

[StraightPipes]

Im with ya Butch.............

Let me ask it a different way; what if "ALL" the contact points in both spiders (or catheads) were to swivel? To eliminate unwanted stress from one end of the blank to the other(stress we cause) we wont be able to cause it if both ends "float" stress free while we dial in.

 

[butchlambert]

I believe one of my Aussie gunsmith friends uses tooling balls to pivot in aluminum radius plates that capture the barrel. I'll guarantee that copper pivots on ea end will not bend or stress a barrel.

 

[jscandale]

I believe one of my Aussie gunsmith friends uses tooling balls to pivot in aluminum radius plates that capture the barrel. I'll guarantee that copper pivots on ea end will not bend or stress a barrel.

absolutely...

JS

 

[StraightPipes]

Butch, your friend known as "kiwi". I stopped thinking about this for a couple days, Im back on it.

Found some " socket head swivel clamps". Might think about starting this swivel thing with those, and add the kiwi pads with a light press fit.