# My new old Unisaw



## coxhaus (Jul 18, 2011)

I have been restoring an old rusted Unisaw Jr which I found on craigslist. The Unisaw Jr is an 8 inch saw very stout weighing in around 240 pounds. I got to the point of needing a fence. Check first picture. I had just sold my other Delta saw which I fixed up on this site when I came across a low priced full Unisaw. It is an old 1950 model. It is in much better shape than the Jr version I had restored and it had the shorter fence rails that I need for my little shop so I sprung for it. So I never really got started with Unisaw JR and I am migrating to a Unisaw. It has a 3 hp motor and a couple of very nice 10 inch blades. The Unisaw only cost me $75 dollars more than what I sold my other saw for so why not. You can see my other saw in the back of the first picture and there is a thread on this site of my other saw. It is more saw than I need but I probably won't upgrade in the future. The guy was having some trouble getting all 3 belts to tension right so he was running it on 2 belts. I am pretty sure I can fix it. I have ordered 3 Gates Premium AX24 belts.


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## Stick486 (Jan 4, 2013)

Lee when it comes to the belts for that saw it works out more gooder that you order them in a matched set....
just spec it...

I have the Vega fences on my Unisaws... 
*SWEET...*

*NOTE:...*
if only two belts were run the sheaves are worn irregularly...
if they are you will never get the belts to pull equally or balanced...


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## coxhaus (Jul 18, 2011)

Thanks stick. The pulley is worn and starting to knife edge. I may have to replace the pulley. The other problem may be the motor pulley is not perfectly aligned to the arbor pulley causing the belts to wear unevenly and excessive wear.

Oh. The Unisaw was a working saw. The guy builds 100 cabinet doors a week so he runs lots of wood through the saw every week.


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## Stick486 (Jan 4, 2013)

coxhaus said:


> Thanks stick. The pulley is worn and starting to knife edge. I may have to replace the pulley. The other problem may be the motor pulley is not perfectly aligned to the arbor pulley causing the belts to wear unevenly and excessive wear.
> 
> Oh. The Unisaw was a working saw. The guy builds 100 cabinet doors a week so he runs lots of wood through the saw every week.


very possible...
don't replace w/ pulleys, use cast/machined/balanced sheaves...
and replace both as a set...
they'll have the matched set of belts too....
this I learned the hard way...

this outfit has excellent CS and products...
dealt w/ them for decades...
Sheaves - V Belt Sheaves from Martin Sprocket & Gear
they have excellent tutorials on installation/computation/alignment...
their catalog is a premium source of information....


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## coxhaus (Jul 18, 2011)

Stick486 said:


> very possible...
> don't replace w/ pulleys, use cast/machined/balanced sheaves...
> and replace both as a set...
> they'll have the matched set of belts too....
> ...


I was going to order a machined steel pulley. I don't fully understand what you are saying stick so fill me in. I looked at the web site but I am lost. How are sheaves different than machine pulleys?


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## Stick486 (Jan 4, 2013)

coxhaus said:


> I was going to order a machined steel pulley. I don't fully understand what you are saying stick so fill me in. I looked at the web site but I am lost. How are sheaves different than machine pulleys?


what shaft sizes do you have...
left or right tilt...

body material..
better balanced and just don't want to wear out...
tighter tolerances...
good to your belts...
method of mounting to the shaft...
you should be looking for a 3¼'' arbor, 3½'' motor and ¾'' shaft sized 3G sheaves... IIRC....


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## coxhaus (Jul 18, 2011)

I have a right tilt saw. The arbor shaft I think should be 5/8 at least that is the blade size. I believe the arbor pulley is 3 1/4 and with a 3400 rpm motor you use a 3 1/2 pulley. I don't know the motor shaft size. The battery is out on my caliper. I need to buy another battery. Which pulley is for a v belt? Is it the tapered bushed sheave or the variable pitch sheave?


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## Stick486 (Jan 4, 2013)

coxhaus said:


> I have a right tilt saw. The arbor shaft I think should be 5/8 at least that is the blade size. I believe the arbor pulley is 3 1/4 and with a 3400 rpm motor you use a 3 1/2 pulley. I don't know the motor shaft size. The battery is out on my caliper. I need to buy another battery. Which pulley is for a v belt? Is it the tapered bushed sheave or the variable pitch sheave?


my 3HP Uni is ¾'', the 5HP 1'' and the 7½HP is 1¼''..
matching sizes on the arbor...
larger sheave on the motor...smaller to the arbor...

will you be changing bearings???
I like SKF, or Fafnir... Motion and/or Kaman can help you there...
https://www.motionindustries.com/taxonomy/Bearings/browse/en
https://ec.kamandirect.com/us/content/products/bearings/default.asp
they do sheaves too.

either but you do not want variable pitch...
Talk to Martin on Tuesday... talk to all three...
get their catalogs...
you will be informed and then some...
brilliant people...


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## coxhaus (Jul 18, 2011)

I will change the bearings if I replace the arbor pulley. I am not going to reuse pulled bearings. I hope when I get the belts I can adjust the motor and tension all 3 belts. If only it could be so simple.

I have never owned any big motors so I am lost on shaft size. That's for the fill in stick. So do you have 3 Unisaws in your home shop? I am not sure I can even keep the Unisaw Jr. It is going to be tight. It would be nice to load my 6 inch dado on the Jr saw and just keep it ready to go all the time. I actually need to work in my shop with everything running to see whether it will work or not.


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## Stick486 (Jan 4, 2013)

I am *far* removed from a home shop...
do have a pair of satellite shops w/ Bosch 4100's...


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## Stick486 (Jan 4, 2013)

coxhaus said:


> I will change the bearings if I replace the arbor pulley. I am not going to reuse pulled bearings. I hope when I get the belts I can adjust the motor and tension all 3 belts. If only it could be so simple.
> 
> I have never owned any big motors so I am lost on shaft size. That's for the fill in stick. So do you have 3 Unisaws in your home shop? I am not sure I can even keep the Unisaw Jr. It is going to be tight. It would be nice to load my 6 inch dado on the Jr saw and just keep it ready to go all the time. I actually need to work in my shop with everything running to see whether it will work or not.


FWIW...
I was editing while you posted...


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## coxhaus (Jul 18, 2011)

Stick486 said:


> I am *far* removed from a home shop...
> do have a pair of satellite shops w/ Bosch 4100's...


No wonder you know everything.


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## schnewj (Nov 18, 2013)

Stick486 said:


> my 3HP Uni is ¾'', the 5HP 1'' and the 7½HP is 1¼''..
> matching sizes on the arbor...
> larger sheave on the motor...smaller to the arbor...
> 
> ...


Excellent advise on changing the bearings! If the pulleys are trashed and the original owner was using it as much as you indicated, then the bearing are trash, also. 

It is much easier to do it now then to have to tear it apart, again, to do it later.


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## jody495 (Sep 11, 2011)

My 10"unisaw came out of a steel mill and was in bad shape. It had a 3 hp./3ph.motor that was burned up,rusty,missing blade guard. I purchased a 3hp motor,pulley, and magnetic on /off switch from grizzly. I also installed 3 link belts that really improved the cut and vibration. Have been using it now for 15 years.


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## coxhaus (Jul 18, 2011)

I have made progress with my Unisaw. I have the new belts on and stretched. I left the weight of the motor on the new belts to evenly stretch them. Boy was the motor heavy to put in the saw. Now I need to check over the wiring and change the plug to a 50 amp welding plug. I have never owned a low voltage starter before so I am taking my time. I have to use my 50 amp welding plugs as I have no more room in my breaker box for any 220 volt breakers.
The days are too hot here in Texas, as today it was a 102 degrees. I only do a little work in the mornings before it gets hot.


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## Cherryville Chuck (Sep 28, 2010)

Looking good Lee.


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## Stick486 (Jan 4, 2013)

oh the envy..
your jewel is looking good Lee....


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## coxhaus (Jul 18, 2011)

Well the Unisaw is up and running. I am thinking the motor is really 5 HP by todays standards. I sold my Rikon bandsaw and was looking at new Bandsaws at Woodcraft and they had some 3 HP units. The 3 HP motors were small and only pulled 12 amps at 220 volt. My Unisaw motor pulls 22 amps at 220 volt so the best I can figure it is more like a 5 HP than a 3 HP. My Unisaw motor is an old Rockwell which Baldor made but it has 3 HP on it. I guess the HP standards have changed.


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## Stick486 (Jan 4, 2013)

4 ~ 4,5 horsepower...
higher efficient motor.. just at 5HP...


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