I finally built a spider for my PM1340GT lathe. It had been on my project list for many months. There are other posts here on the forum for a spider but I thought I would add this one to the list.
I used this project as an opportunity to apply Fusion 360 and learn a bit more about the latest generation of 3D modeling software. Learning Fusion had also been on my list for months. The drawings are attached here as PDFs for those who may want to use this spider concept as a start.
I built the spider from 4140 chrome moly heavy wall tubing.
As you may know, for the PM1340 you will need to open up the end cover a bit to accommodate the spider. I did that on my PM935TV mill with a boring head and it worked out quite well.
I turned/bored the spider using a recently acquired 4 Jaw combination chuck and was pleased with the accuracy of the chuck. I did the milling and drilling needed using my indexer on the mill.
The finished spider fits the spindle as hoped and the bores match up very well. I got a little carried away making some brass tipped “workpiece holding” set screws but this spider will hold down to a 0.110” diameter workpiece. Yes, this is small but I recently turned some very small copper tubing where this would have eliminated red rags stuffed in the spindle for support. When and if I need it, I may add an indictor mount on the end cover of the machine to center the workpiece.
Thanks to Mark J. (@mksj) for sharing his concepts so I didn’t have to start from scratch. Thanks to Brad (@bss1) for his idea for the brass jam nuts.
I used this project as an opportunity to apply Fusion 360 and learn a bit more about the latest generation of 3D modeling software. Learning Fusion had also been on my list for months. The drawings are attached here as PDFs for those who may want to use this spider concept as a start.
I built the spider from 4140 chrome moly heavy wall tubing.
As you may know, for the PM1340 you will need to open up the end cover a bit to accommodate the spider. I did that on my PM935TV mill with a boring head and it worked out quite well.
I turned/bored the spider using a recently acquired 4 Jaw combination chuck and was pleased with the accuracy of the chuck. I did the milling and drilling needed using my indexer on the mill.
The finished spider fits the spindle as hoped and the bores match up very well. I got a little carried away making some brass tipped “workpiece holding” set screws but this spider will hold down to a 0.110” diameter workpiece. Yes, this is small but I recently turned some very small copper tubing where this would have eliminated red rags stuffed in the spindle for support. When and if I need it, I may add an indictor mount on the end cover of the machine to center the workpiece.
Thanks to Mark J. (@mksj) for sharing his concepts so I didn’t have to start from scratch. Thanks to Brad (@bss1) for his idea for the brass jam nuts.