Hopefully the next thing we hear about this saw is that it’s running!
Hopefully the next thing we hear about this saw is that it’s running!
low probability. The threads on the arbor not is extra fine, 28 threads per inch and its a right handed nut for the left tilt unisaw
5/8-28 seems to be a common size in electric pole hardware. I had no idea. So the stuff is out there. Is it standard sharp threads or acme, buttress etc?
Bil lD.
https://alliedboltinc.com/Poleline-H...-WITH-NUT~8237
Like Bill said...are you sure this is not an Acme thread?
Rick Potter
DIY journeyman,
FWW wannabe.
AKA Village Idiot.
Are you sure it’s really 28tpi? That is super fine for an arbor, about 3 times more threads than the old style.
Whatever happened with this?
its not the blade nut. Its the nut on the opposite end of the arbor, against the bearing. Yes its 28 tpi.
And that’s why I was confused. Did you get it figured out yet?
Sorry. Here the history............
- While installing new arbor bearings, I must have deformed the top threads while forcing the bearing onto the shaft. Of course I did not realize this until then end of this adventure.
- I discovered the bad threads when trying to screw on the arbor nut.
NOTE: this is not the blade nut but the nut on the opposite end of the arbor next to the bearing. One the part list I have for this next generation Unisaw, its item #37 PN 902012009847S SPECIAL NUT.
- I attempted to screw on the "special nut" and forced it and in doing so also damaged the threads on the nut.
- I thought I must have cross threaded the nut and looked for a "special nut" to buy. All parts houses showed not in stock or even obsolete. When I called Delta they said the nut has been back ordered for months and could not give me a due date. Eventually I found the nut on Ebay from a person who specialized in Unisaw and Bieasemeyer parts (machacc aka Ron) I bought the nut from him for $14...desperate yeahh I know. I also bought an arbor but subsequently cancelled it (youll see why as you read on).
- I try file repair of the threads but no luck
- Looking to buy a 28 TPI 5/8 tap and die I found them to be as much as a new arbor (hence I ordered an arbor for $60) but I did finally borrow a 5/8 28 tpi tap (no die) and was able to clean up the threads on the original nut. I was able to do this by hand strength only but definitely could feel the resistance and the soon the nut was freely moving on the tap threads. Success right? Not so fast.
-- Thinking I had the problem solved and went to install the nut and same problem...maybe a quarter turn and stop. So now I know the threads on the arbor are bad.
- Having ordered a nut and an arbor I had nothing to lose with my existing nut/arbor so I carefully line up the nut on the arbor and using a wrench forced the nut on, back and forth, much like you would do with a die. After the nut got past the 1st thread it freely screwed on and after a few back and forths the nut and arbor were working again. I cancelled the arbor order but unforuntaly could not cancel the Ebay nut order
- I installed the arbor now with the old nut (still no Ebay nut arrival) and the saw work wonderfully.
- I measured runout on a Forrest blade of .003. I balanced quarter on edge while the saw ran. Happy now but a big lesson learned.
Good to hear you have it working. Next time you can heat the bearings and they’ll just slip right on. Or, just don’t do whatever you did to bugger up the threads! Lol. Mistakes are all learning experiences. We’ve all goobered up threads at one point, or 6 points.
repairs.png
Love XKCD! reading that OPs final response made me think of this