a 1-1/2HP motor ripping 2x material is a tad underpowered, in my opinion
even a 3hp unisaw can struggle on 2x
even a 3hp unisaw can struggle on 2x
Unisaw disconnect
- Thread starter acer66
- Start date
rlitman
Well-known member
There's something to this. If he's got a nice and sharp ripping blade it should do ok, but if the blade is a combo or it's gummed or not all that sharp, then you would really feel it. The only time I've had issues ripping 2x stock with my 3HP motor was when the reactive wood pinched my riving knife.
I agree that a good ripping blade is a must. I’d also use a 1/8” thin kerf blade as well.
Zeke
Well-known member
I used to have the 1 1/2 HP Delta Contractor's TS and it was tough to use on thicker material. It was no good with framing lumber.
I still have one in storage, but before it was replaced with a Unisaw it would trip breakers all the time when ripping, used to move to another circuit & keep going, was going to swap the motor over to 240V & never did. A 1 1/2 HP motor on 120 volts is iffy.
same here. sold it & bought a 3hp unisaw
Was thinking about a 4 HP motor but was too lazy to rerun the circuit for the saw, so went with a 3 HP, later ended up with 2 more Unisaws, what was funny is they both were 3 HP 1Ø machines, & manufactured in the same year.
Hey,
Thank you for the quick and helpful responses as usual.
Motor is wired for 240V.
The heaters were replaced with ones recommended in the thread.
The switch box is clean as a whistle.
I was ripping a bunch of 2x‘s to make around 150 stakes for concrete forms out of a pile of scrap so the saw did not get much of a break until it tapped out.
The blade was a somewhat sharp ripping blade but could have had less teeth.
I try to get better in changing the blades for the task at hand.
Never thought about a proper cabinet saw could have an underpowered motor.
But ripping a bunch of 2x’s in one pass is a lot to ask come to think about it.
Might look for stronger motor when prices come down again.
Thanks again.
Thank you for the quick and helpful responses as usual.
Motor is wired for 240V.
The heaters were replaced with ones recommended in the thread.
The switch box is clean as a whistle.
I was ripping a bunch of 2x‘s to make around 150 stakes for concrete forms out of a pile of scrap so the saw did not get much of a break until it tapped out.
The blade was a somewhat sharp ripping blade but could have had less teeth.
I try to get better in changing the blades for the task at hand.
Never thought about a proper cabinet saw could have an underpowered motor.
But ripping a bunch of 2x’s in one pass is a lot to ask come to think about it.
Might look for stronger motor when prices come down again.
Thanks again.
rlitman
Well-known member
Ok, so it sounds like the heater was working as desired, and is protecting your motor.
A standard blade is 1/8" wide. A thin kerf blade removes less wood, which in turn uses less power. That might have been all you needed.
Personally, I do almost all my work with a 60T full kerf ATBR blade, because it CAN do everything. However, even at 3HP, my go-to blade would be a terrible choice for ripping stakes, because just because it makes a clean cut doesn't mean something else would be way better. So I totally understand the desire to not switch blades, but I'm betting that was your problem.
A thin kerf blade can warp with a lot of ripping, don't get me wrong I like thin kerf blades but like everything there are limitations.
rlitman
Well-known member
Not all blades are created equal. Full kerf blades can warp too. Good blades have relief cuts to handle thermal expansion, improve cooling and dampen vibration that creates noise and heat. Cheap blades are flat plates of steel with teeth on the perimeter.
The biggest gotcha here is that nowadays most thin kerf blades are marketed towards underpowered (and cheap) saws, and more importantly the owners of cheap saws, so thin kerf blades are largely synonymous with budget blades. And yes, a cheap blade will have warping issues when over-used. Even so, quality thin kerf blades to exist, and I doubt you'd have a warping issue with a Freud LU87R010.
Zeke
Well-known member
I had written out a bunch about blades and then deleted it. Basically you guys covered what I had to say.
Yeah, I have a ripping 10" blade with about 20 teeth. It's scary to look at but shouldn't be as it's actually safer. Low tooth count was/is another way to make blades for less and I think they got a bad rap for that reason and the fact that they don't leave a pretty cut. You get a decent ripping blade and it will chew boards as it should. They make a lot of chips.
Check amp draw on the motor while cutting.Hey,
Thank you for the quick and helpful responses as usual.
Motor is wired for 240V.
The heaters were replaced with ones recommended in the thread.
The switch box is clean as a whistle.
I was ripping a bunch of 2x‘s to make around 150 stakes for concrete forms out of a pile of scrap so the saw did not get much of a break until it tapped out.
The blade was a somewhat sharp ripping blade but could have had less teeth.
I try to get better in changing the blades for the task at hand.
Never thought about a proper cabinet saw could have an underpowered motor.
But ripping a bunch of 2x’s in one pass is a lot to ask come to think about it.
Might look for stronger motor when prices come down again.
Thanks again.
I assume you are over loading the motor.
1-1/2 HP on a tablesaw is not enough for ripping thick stock. My 1-1/2 HP contractors saw could barely do it, and I had to use the correct blade. I also sold that saw and bought a 3 HP Unisaw. It is a world of difference.
Last edited:
even a 1-1/2 HP contractors saw on 240 will struggle with ripping 2x. just not enough ummmf
1-1/2 HP is the same whether it is a contractor saw or a cabinet saw.Hey,
Thank you for the quick and helpful responses as usual.
Motor is wired for 240V.
The heaters were replaced with ones recommended in the thread.
The switch box is clean as a whistle.
I was ripping a bunch of 2x‘s to make around 150 stakes for concrete forms out of a pile of scrap so the saw did not get much of a break until it tapped out.
The blade was a somewhat sharp ripping blade but could have had less teeth.
I try to get better in changing the blades for the task at hand.
Never thought about a proper cabinet saw could have an underpowered motor.
But ripping a bunch of 2x’s in one pass is a lot to ask come to think about it.
Might look for stronger motor when prices come down again.
Thanks again.
Good luck finding a used motor for a Unisaw. The motor has a special mount and used 3 HP motors are rare. New ones are spendy about $1,000!!
I would sell the saw and buy a 3 HP Unisaw. I bought a 3 HP Unisaw a year ago for $900.
https://www.garagejournal.com/forum/threads/my-new-to-me-tablesaw.490880/#post-9359517
Last I looked a 3 HP Leeson for a Unisaw was $600, was shocked at how much they went up as mine was a little over $300 including shipping.
Firebrick43
Well-known member
I have a 97 5hp unisaw that was installed in a school and then the school shut down their wood shop in 98. One of the teachers bought it a decade later when they finally liquidated the shop. (ironically they are building a new shop now)
Anyway he removed the 5hp 3 phase motors and installed 3hp single phase motors in them and then sold them. I hoped like hell he still had the 5hp motors but scrapped them, I would have ran it with a VFD.
If you find a 3 phase machine/motor, a vfd is cheaper than replacing the motor. It also allows for slower start ups and faster stops if programed right. My unisaw thumps something fierce on startup about 50 percent of the time.
My powermatic jointer and belt sander were 3 phase machines out of IUPUI and I got them cheap because they were. I run them off of a VFD and I am very happy with that setup. I use the original start/stop buttons to control it but that is just a low voltage control signal to the vfd inputs, there is no amperage running thru them.
Anyway he removed the 5hp 3 phase motors and installed 3hp single phase motors in them and then sold them. I hoped like hell he still had the 5hp motors but scrapped them, I would have ran it with a VFD.
If you find a 3 phase machine/motor, a vfd is cheaper than replacing the motor. It also allows for slower start ups and faster stops if programed right. My unisaw thumps something fierce on startup about 50 percent of the time.
My powermatic jointer and belt sander were 3 phase machines out of IUPUI and I got them cheap because they were. I run them off of a VFD and I am very happy with that setup. I use the original start/stop buttons to control it but that is just a low voltage control signal to the vfd inputs, there is no amperage running thru them.
I didn't shop, just a quick Google, and they were $900.
EMW e-commerce
www.electricmotorwholesale.com
Quite a discount from over $2k retail!
Not surprised anymore as it was not recent when I looked at them, and it's going to get a LOT worse.
if ever I needed a motor for my unisaw, I would seriously look at removing the welded bracket on the OEM motor & re-welding it to a new common motor. or fab some new brackets .
But can you weld to the motor case and not destroy the windings? I feel it would be risky.
I am not certain the adapter mounts are available any longer.
Well, yes they are!
https://www.renovoparts.com/43-802-motor-adaptor-bracket-for-right-tilt-unisaws/
probably I wouldn't risk it, but just in general, I would look at buying a more readily available motor & re working the bracketry to fit
I have 3 phase 5hp unisaw motor if your looking.