5 HP vs 3 HP Cabinet Saw - Which to Buy

[Scott Myers]

I've been in cabinet saw buying mode for a bit over a month now and have it finally down to the PM2000. The real question comes down to 3 HP vs 5 HP. I'm just a weekend warrior, doing built ins in my house, furniture projects, etc. Before, I used my old benchtop saw and used a friend's saw when I had big heavy work to do.

Some people, probably the majority, tell me that 3 HP is plenty. But there are some that say no, get the 5 HP. It's best for dado cuts, ripping thick hardwood without burns, etc. I don't want to buy a 5 HP just to satisfy my inner Tim Taylor syndrom.

So how about some other's opinions on the subject. I'm certain that this is going to be a ride of opinions.

[Doug Shepard]

I've never come close to bogging my 3HP PM66 down with either a full dado stack or ripping 8/4 hardwood (w/ no burning). But if you want the Binford 2000 model, go fer the 5 horsies:-)

[Mac Cambra]

I will tell you that being a person that owned a 3HP Unisaw and now owns a 5HP Sawstop the difference in power has not produced anything that I would consider noticeable.

I tend to agree with all of those folks that say 3HP is plenty. I bought the 5HP basically because I had the same questions as you, throw in the fact that I was spending so much on the saw what a couple hundred extra bucks, why not get the extra power. Hindsight tells me I should have saved the money and spent it on something else. Don't get me wrong, I love the saw as is but I think I would have loved the 3HP just as much.

[Karl Brogger]

5hp. Because there are times when it still doesn't have enough power. There is nothing to be gained with less power. To be honest I think the higher hp saws are safer too. Your less likely to get something to bind on the blade and actually catch. When something does come whipping out the difference in speed won't be enough to notice the difference in pain.


If its the couple hundred dollar difference that is affecting the decision you need to re-evaluate your purchase.

[Michael Lutz]

When I was looking at cabinet saws, I went with the 5 HP over the 3 HP. I didn't want to second guess my decision. In my case it was only $100 more for the 5 hp. I have the PM66 5 HP.

Mike

[Joe Mioux]

What would hurt more; kickback from a 5hp motor or a 3hp motor?

Seriously, I have a 3hp and it is more than sufficient. My old contractor saw was 2hp and I cut some 3x's old hard Oak with it and I never had problem.

Patience with the feed rate helps...... as does a properly squared up blade/fence combination, and a good blade.

Joe

[Jamie Buxton]

Buy the 3 hp saw plus a router. The router will make a bigger change in your shop capabilities than the extra two hp. If you already have a good router, fill in your own choice of tool. The result stays the same.

[Karl Brogger]

What would hurt more; kickback from a 5hp motor or a 3hp motor?

If you can tell the difference you're better than me.


I have a screwy way of using a tablesaw. I run material through it as fast as possible. This is especially true when cutting solid stock, as the cut is not a final product, it will always get planed, or jointed.

[Von Bickley]

Buy the 3 hp saw plus a router. The router will make a bigger change in your shop capabilities than the extra two hp. If you already have a good router, fill in your own choice of tool. The result stays the same.

I agree with Jamie....

[Peter Quinn]

If you were a pro running that saw hours each day every day often with the blade above two inches high, lots of 8/4 production runs, I'd say get the 5HP no brainer. Nice to have the over head. Worth the few extra bucks over a lifetime. Even if you thought you might wind up on a long job like that I'd say get it, and by long I mean years. But in your home shop? Even a devoted serious part timer isn't going to tax a 3HP powermatic cabinet saw.

I work in a cabinet shop with three 5HP three phase PM66's in use. In my own shop I have a 3HP 66. No difference. Zilch. Nada. Its like, do you want too much power, or WAY too much power at your disposal. My 3HP? No burning, no bogging, spins a dado like a champ. You are only spinning an 1/8" kerf 10" blade, this does not require 5HP and rarely requires 3HP. If you were asking about shapers, I'd say yes, that extra two HP will make a big difference when you spin bigger cutters, but on a TS you never spin bigger cutters than a 3HP motor can handle, even a molding head will be fine.

One real issue in favor of the 3HP is power. My electric company never seems to lower rates but often raises them. Why would you want a bigger wire,, a bigger breaker and a larger amperage draw JUST CAUSE? Every time you push that green button you will be using more power than you need. Given that you do this part time or on an occasional basis this may be of little concern to you, or it may not.

So in conclusion, it does not matter. 5HP if you want, 3HP if you like. I doubt you will be able to tell the difference without looking at the motor plate.

[Jack Camillo]

I had the same question once, and went with 3hp. Wish I did the 5hp. Like someone above said, "what's to be gained by going with the 3hp?" On most saws that offer both, the price is the same or very close.

[Gary Curtis]

For the extra $100 I got my General 350 with the 5hp Baldor motor. Like others here, I haven't run into a situation which 'demanded' the extra power.

But on one piece of 3/4 ply, I managed to stall the blade by twisting the wood. I anticipate sawing an amount of wet wood since I live in a forest.

On the whole, it is slight overkill. By the way, if you were to buy that Baldor motor outright, it would cost close to $500.

Gary Curtis
Northern California

[Dave Lehnert]

I used a 1 1/8hp Shopsmith for years and never had a power issue. I now have a 3hp Jet saw and it is way more power than I would ever need.
For home use you will never wish for the 5hp. My saw never ever has bogged down. If it does, you need to get your blade sharpened.

[Tom Veatch]

...So how about some other's opinions on the subject...

OK, here's my opinion:

An electric motor only develops enough horsepower to maintain it's speed near it's rated RPM. The only time you will ever use any of the extra 2HP will be if whatever you're doing will bog down a 3HP motor.

I've never bogged down my 3HP saw so I would have never used any of the "reserve" power, even if I had it.

Another thing to consider is that it will probably cost a little more to run the 5HP over the 3HP even doing the exact same operations.

Sample Data for a typical 5HP motor:
Efficiency (%):
82.5 (Full Load) 81.3 (75% Load) 77.4 (50% Load) 65 (25% Load)

And for a typical 3HP motor:
Efficiency (%):
82.4 (Full Load) 81.3 (75% Load) 77.4 (50% Load) 64 (25% Load)

Now compare the two motors, but remember that doing a particular task, the 5HP motor may be operating at 50% while the 3HP will be at about 83%. Compare the efficiencies with both motors developing the same HP-lightly loaded 5HP, more heavily loaded 3HP. I expect that you'll find that for every task that requires 3HP or less, the 5HP motor will be operating at a lower efficiency and cost more to operate than the 3HP. Not enough to make a big difference in the electric bill, but it will cost a little more.

Don't forget that in the care and feeding of the 5HP machine, you'll have to size for the maximum amperage draw of the motor. So you're looking at a 240v/30a/10ga circuit while a 240v/20a/12ga circuit would be quite sufficient for the 3HP. So, unless you already have the 30a circuit available, you've got more upfront costs than just the purchase price.

It's a rare hobbyist woodworker that will consistently work a 3HP saw to it's limits and need 5HP. I'd have a different opinion if you were talking about equipping a high volume, high production cabinet shop.

Now with all that said, it's time to state my recommendations. I recommend that you say, "To Blazes with all these opinions!" and go out and buy the one you want!

[Neal Clayton]

i have bogged down my 5hp pm66 once. i was trying to rip an old growth 2x6 roughly 10 feet long that had a slight, almost imperceptible cup, and it also had a huge sap pocket in it that i couldn't see beforehand. it was a helluva board, there were about 55 rings per inch in the end of it, so the blade was struggling with it regardless of its imperfections. the stickiness of the sap coupled with a slight bind on the blade stopped it, luckily the board didn't fly off, only reason it didn't was i had some featherboards on the table to try and hold the board, it was too heavy for me to feed completely by hand without any assistance.

that said, i agree with the other statements that there's nothing to be gained from less power, and much less stress on the motor if you have power to spare.