Here is a picture of my spider on the left hand side of the headstock of my old Clausing lathe:

my spider



My brother's is on a Jet lathe.

picture of my brother's spider with headstock cover on



My brother's spider with the headstock gear cover off and test indicator being used to dial in the muzzle

See the little test indicator stylus going into the muzzle? Looking at that indicator dial allows the operator to adjust the spider screws until the muzzle is centered, just like centering the breech in the big 4 Jaw chuck on the right hand side of the headstock.



The spider only works well if it can pivot the barrel in the lathe chuck. To make a pivot, I use a piece of copper wrapped around the breech for the lathe chuck to pinch. The wire then pinches the barrel breech. If the chuck jaws are not perfectly aligned with the headstock axis, barrels will just bend if tightly held in the lathe chuck. If they are perfect, who needs a spider?





Look to the left of my hand.

See that piece of copper wire wrapped around the barrel?

..

I was looking for something on my PC today and ran across these pics. Here is how I made a spider and how I have a dial indicator attached. I chose to tap a hole in my lathe and permanantly attach the indicator. Well, I can unscrew it, but you know what I mean. It is not dependent on a magnetic base. It is very sturdy and gives good readings.

[image]http://www.imagestation.com/album/pictures.html?id=2133267538&idx=1[/image]

[image]http://www.imagestation.com/album/pictures.html?id=2133267538&idx=2[/image]

Just thought I would throw it out. I saw it some where else on the net a few years ago. Others have seen my indicator attaching method and did it the same way. Just another option for you

Marc,
I cut and pasted the html from your link and, being a non member of image station, all I can see is that it looks like you are dialing in with a dial indicator on the outside of the barrel.

I have been dialing in with a test indicator on the grooves. If the search function ever gets working here again, there are some guys dialing in on a tapered rod lodged in the bore.