Simplex X-L soundhead projector drive gear spring

[Jesse Crooks]

I’ve been working on a pair of X-Ls that currently have rounthane belts, which I’d like to replace with V belts. Before I pull the projector drive gear to access the pulley, I wanted to check whether there’s anything tricky about setting the tension on the shaft spring. I’m assuming you just need to tighten it enough to eliminate end play? Any gotchas to watch out for? Seems easy enough but they’re not my projectors and there’s nothing like a spring going flying to ruin your day.

Photo of the equivalent spring on an SH-1000 I had access to today for reference.

[Sam Chavez]

As I recall there is enough room to slip a belt around and over the gear and onto the pulley without removing the gear. The trick is to find the right size belt depending on what you are using for a reel arm or magazine.

[John Eickhof]

hi sam, the factory spring is sized to have a machined flat washer against the steel gear and one against the nut, tighten the nut down completely. all the spring is designed for is to allow the steel gear to laterally move should there be excessive start up shock. the washer with larger id goes against the gear, the smaller id goes on the threads, the nut locks it in. do not leave the nut loose or it will back off while running! i have nos parts on hand if you need anything, the take up pulley will accept a 5/16" dia belt. the sh-1000 set up is the same only the part numbers are different but interchange no problem! jr

[Mark Gulbrandsen]

If you need to, remove the nut, washer and spring and slide the gear out just enough to get the V-Belt on the pulley. Just be careful that the key in the shaft does not fall out. When you remove the spring and washers you can see where the slot is in the gear. Put it at 12:00, then slide the gear back just enough... All this is assuming the belt can't slip in...