|
Post by oregon on Mar 8, 2020 22:59:04 GMT -5
Just a future reference when someone else runs into this...
I had just redone another Lortone LS-10 saw which made me want to drag out my basket case ST-10 and get it dialed in.
LS-10 cut beautifully after a few break in cuts, new mk303, 1:1 pulleys to bring the new blade up to speed. Dial indicators to line everything up, tighten up the brass screws as much as possible. After doing the same to the ST-10, it cut 'ok' but not near as nice. I had put a latching relay on mine (oil bath once, never again) and noted that it looked like the same brevel gear motors were in the auto feeds.
Finally realized that on the old ST-10, the auto feed rod is a 3/8-16, while the newer saws have 3/8-24 threaded rod (16 threads per inch vs 24) I don't know if the st-10 originally came with slower rpm motors but mine's clearly feeding too fast. Maybe someone swapped out for a quicker motor because they wanted to cut faster? I'd personally just cut much slower and not spend as much time polishing later. Not sure if I'll search for a slower 2.5-3 rpm motor, or just change out the rod/split nut yet.
There are also slight differences how the lock collars and bronze bushings for the feed are set up, Not sure if it's better to have the bronze locked to the shaft and turning in the aluminum casting, or have the threaded rod turning in the bronze bushing -imagine that might wear quickly, but wearing out the casting would certainly be worse.
|
|
quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
|
Post by quartz on Mar 9, 2020 23:24:28 GMT -5
You always want the most easily replaceable and cheaper part to be the wear point, the bushing.
|
|
|
Post by oregon on Mar 10, 2020 10:43:43 GMT -5
You always want the most easily replaceable and cheaper part to be the wear point, the bushing. yeah, I imagine that's why they switched. Was a little baffled that the original had the bushing locked to the rod, but I maybe the threaded rod rotating inside the bushing wears a bit quicker and that might have been their reasoning?
I'm guessing someone put a newer version feed motor on this, can imagine they originally sold it feeding ~ 3 min/inch! Motor's seem hard to find, so looks like a couple hours in the shop to make a new split nut & finer feed rod.
You don't happen to have any of those spare cheap dayton motors Grainger was clearing out - knew I should have stocked up on a few!
|
|
quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
|
Post by quartz on Mar 10, 2020 23:31:54 GMT -5
Nope, no spares, should have bought a case of them. If your feed rod was running in aluminum, bushing locked to rod, the aluminum will wear way faster than the brass unless it is 7075 or some other high-tech alloy, doubtful.
|
|