No chip tray seems like a bad idea
No pull out tray ..you have access in the back to sweep out the chips. But yes, pull out chip is much better for someone with OCD about keeping things cleanYeah. I'm confused.
It looks like the stand is backwards and the tray is just not installed. I'm sure we're missing something.
I did my first short barrel today, 16.5". I threaded the muzzle using the Viper fixture. It works okay, but wasn't as happy with .050" cuts as it was .020" cuts.
After the muzzle was threaded, I threaded on my 10" barrel extension. I used about five wraps of teflon tape. Then I chambered using the inboard and outboard spiders and flush. It worked well. I was able to get a nice tight dial in and had no leaks.
I think a delrin busing would be a better option than the Viper for muzzle threads, if I could ever find time to make some. I left the Viper on the 4-Jaw when I removed it from the lathe, though it's wasn't terrible dialing in the Viper.
I built a viper/gretan jig clone. I used it once. Stuff moves. It's parts sticking out of parts. I'm sure you could make it work with a ton of really light cuts, but I never liked it... because I knew how easy it was to move stuff.
I immediately got to work on this:
View attachment 1389783
I've done a number of short barrels in this and I can't recommend the design enough. You can build one in a day.
Its got the same contact points on the barrel no matter if its a 10 or 36” lathe, but to answer your real question no, the outboard spider will be more rigid than holding one spotWould a TBAS or viper style fixture on a 16x40" 4000lb machine with a D1-8 and 80mm spindle have as much rigidity as a small 13/14x40" 1500lb machine running an outboard spider?
Yours is indeed done right, with a direct mount to the base plate, and looks very nice. But what about your design makes it hold better than the Viper?