How much power is enough? (Is there such a thing?)

[tomwassmer]

Hey everyone!

I have been messing around in the shop for years and have decided to kick it up a little recently. I have always had marginal tools and I think it's time to upgrade my tablesaw to a machine I am happy with and will enjoy using (unlike my current tablesaw) for the rest of my life. After spending some time in a friend's shop, I decided the table saw was the first thing that I had to replace/add to my arsenol. He had a Grizzly contractors saw that I really enjoyed using. Shortly thereafter I started stockpiling Grizzly gift cards at every opportunity to save up for my dreamsaw. Now I know Grizzly tools are not the extreme top of the line but I am not in a position to drop thousands on one of those. Anyway, I have been eyeing up Grizzly's G1023RLWX 10' 5HP cabinet saw. Recently I have started to wonder if 5 hp is overkill. The type of work I'd like to do with it would be some cabinet construction for my house/shop, built-ins (per my wife's request) and other smaller projects. I would also occasionally use it for heavier construction projects such as a deck for my yard. With that being said, I would appreciate any input on whether I'd ever need 5 hp, or if the 3 hp would be more than enough power. The money I would save may be better invested on other tools, however if 5 horses would prove valuable, I'll just save that much longer! Thanks for your input!

[mdbuilder]

I have a 3 hp Delta Unisaw (old one, not the newer version) and the only time I"ve ever detected any slowing at all is when ripping 8 quarter+ maple or white oak and intentionally feeding it very fast just the try and slow it down. Normal feed rates are never a problem, I use a full kerf rip blade for the thick stuff...

[Keggers]

I have the Grizzly 12" 5hp cabinet saw. It's NEVER bogged down on me no matter what type of wood I'm cutting. Do you need a 5 hp? Probably not. I'm just a big "Toole Time" fan and I just had to buy the "MORE POWER" saw. I like the 12" blade because I cut some pretty thick material.

[Vic]

5HP is totally unnecessary. Buy the 3HP and spend the extra on a good dado set and high end combo blade.

[wilburpan]

This isn't a table saw situation, but at Woodworking in America I went to a session taught by Michael Fortune on setting up a bandsaw. He said that for a 14-15" bandsaw, using a motor more than 1/2 HP was unnecessary. He also said that you could do resawing on such a bandsaw with such a motor up to the 12" or so capacity that a 14" bandsaw has with a riser.

Just in case you didn't know, Michael Fortune is a professional woodworker, and uses bandsaws extensively in his shop in a commercial environment. It seems that he uses bandsaws for many operations that most people would use a table saw for: making tenons, ripping hardwood, and so on.

Now, I know that he knows that larger bandsaws have larger motors than the 14-15" bandsaws that he is talking about. I think his main point was that for a typical home workshop, a lot of work can be done with a bandsaw with a modestly sized motor, and that if you think you need a bigger motor, you probably really have a problem with your blade or the way the bandsaw is set up.

This is something that I've been thinking about for a while. My bandsaw is an old Walker Turner 16" bandsaw from the early 1940's, and it has a 1/2 HP motor. It has a 10" resaw capacity, and 1/2 HP was the biggest motor they sold with the bandsaw back then. I'm guessing that woodworkers 70 years ago needed to resaw wood just like we do, so if it really took a more powerful motor to do so, they would have been selling bigger motors then. Walker-Turner cabinet table saws, which were built more heavy-duty than Grizzly table saws are today, came with a 1 HP motor.

My bet is that the same principle applies to table saws. If you need a 5 HP motor, maybe the issue is really with your blade or your setup, not so much the motor.

[DALSAW]

I'm using a 1.75 HP hybrid saw and I haven't bogged it down in the 2 years I've had it. I guess that what it boils down to is your preference if you got the money and power requirements to run a 3 or 5 HP 220 volt saw then go for it.

[jmwert]

In July I purchased the G0691 10" 3HP and love it. I do a lot of cutting of 8/4 red oak and the saw flies right through it. It also has the nicer fence than the 1023 style of saw. Both saw are good saws for the money but in my opinion get the 3HP of either and put the extra money into something else.

[nateswoodworks]

I have a Steel City 3hp cabinet saw and it has more than enough power for me, and I cut a fair amount of 8/4 Oak, Maple, Rock Elm and such. I have always thought of the 5hp as a street car with nitro anda blower-super awesome but not needed. If it is used it for 50hr work weeks it may be a different story, but my opinion is that it is overkill. I know the cabinet shop around here has a 1950's Unisaw with a 5hp motor and says it is just for bragging rights. Just my thoughts but you might want to use the extra money for the next tool on your list.

Nate

[jimmykx250]

I have a 1-3/4 hp table saw and with a good blade nothing stops it! I dont think 3hp is required i would save the extra cash for upgrades like a sweet fence or dado blade set.

[bywc]

lol I dont even know what hp mine is it doesn't say its just a 15amp porter cable contractor saw and I have yet to hear it bog down was using it today for dado's and not an issue so not sure what 15 amp translates to in HP

[Guest Trace]

The 5hp is overkill as stated above. A 3hp will do the job no matter what. The real difference is the voltage requirements, 110v or 220v. My 220v saw doesn't cut any faster or better than the 110v. I believe the real difference is the sharpness of the blade being used. Both cut well. The only reason I even have 220v in my shop is that the saw cannot be rewired for 110v. It was made in 1965. Neither of my saws are the very top of the line models, but I like them, so they get used a lot.

[PaulMarcel]

So I have a question... I also agree that 3hp is the right place to be (as I wrote before), but I'm wondering why anybody would buy a 5hp or higher 10" table saw. I can understand Keggers with his 12" saw that the extra 2" height on the blade would require considerably more torque when plowing through those 16/4 leg blanks. But when for a 10" saw?

To add to the numerous 1.75hp answers, when I had a 1.75hp PM64S, only once it bogged down and it was because some clumsy dope who will remain nameless hit the splitter hard with something earlier in the day and didn't verify that it moved and was setting up a toe-in condition. I will say that the PM64 was rewired for 220V and I loved it in that mode. No, gives no extra power, but the startup surge current was well below the breaker in 220V mode whereas in 110V configuration, it sometimes popped the breaker on startup (rare, but a nuisance).

Lastly, I think the older saws mentioned as being of a particular hp rating were rated honestly. These days the rating uses all kinds of creative "peaked developed" "peak" "wished for" etc. measuring methods.

[wilburpan]

Lastly, I think the older saws mentioned as being of a particular hp rating were rated honestly. These days the rating uses all kinds of creative "peaked developed" "peak" "wished for" etc. measuring methods.

Rating motors by "peak" HP is true for the sorts of motors that go into routers and shop vacs. For the motors that are going on machinery, though, the HP ratings are still accurate.

What may change a bit is the torque band, especially if you are comparing older repulsion-induction motors to the ones made today. The 1/2 HP motor that I have on my 1940's bandsaw, though, isn't one of those motors, even though it's the motor that came with the saw when it was first bought by the guy who sold it to me, and looking at the motors from the 1940 Walker Turner catalog that I mentioned above as examples, none of them were R-I motors, either.

[Onboard]

lol I dont even know what hp mine is it doesn't say its just a 15amp porter cable contractor saw and I have yet to hear it bog down was using it today for dado's and not an issue so not sure what 15 amp translates to in HP

Paul, the rule of thumb for electrical horse power is that for every 746 watts of energy developed (output) your generating 1 hp. So, if your saw motor is rated at 15 amps, and is plugged into a 110 volt source, potentially it will generate about 2.2 hp. Factoring in motor efficiency you may not always see a full 2.2 hp output. If the motor was 85% efficient you would then see about 1.9 hp developed. [P (power in watts) = I (current in amps) X E (voltage in volts) so, 15 amps X 110 volts = 1,650 watts. 1,650 watts / 746 watts = 2.2 hp]

[Vic]

Paul, the rule of thumb for electrical horse power is that for every 746 watts of energy developed (output) your generating 1 hp. So, if your saw motor is rated at 15 amps, and is plugged into a 110 volt source, potentially it will generate about 2.2 hp. Factoring in motor efficiency you may not always see a full 2.2 hp output. [ P (power in watts) = I (current in amps) X E (voltage in volts) so, 15 amps X 110 volts = 1,650 watts. 1,650 watts / 746 watts = 2.2 hp]

Excellent, Onboard!! I do those calcs only rarely, so I have to refer to my electrical handbook. Just for information sake, most of the motors I deal with (irrigation, screw compressor, etc.), they are between about 85 and 95% efficient. I'm guessing motors like Baldor that are reputed to be built to a higher spec are in the higher efficiency range.

[bywc]

Paul, the rule of thumb for electrical horse power is that for every 746 watts of energy developed (output) your generating 1 hp. So, if your saw motor is rated at 15 amps, and is plugged into a 110 volt source, potentially it will generate about 2.2 hp. Factoring in motor efficiency you may not always see a full 2.2 hp output. If the motor was 85% efficient you would then see about 1.9 hp developed. [P (power in watts) = I (current in amps) X E (voltage in volts) so, 15 amps X 110 volts = 1,650 watts. 1,650 watts / 746 watts = 2.2 hp]

Ah ok thanks man! I had no clue how to calculate that or even where to begin looking to figure it out. so for my needs 2.2hp seems to be more than enough but i am not cutting 8/4 hardwoods either things might change in the future but for right now about 4/4 is about thickest im cutting.

[Beechwood Chip]

My experience with computer gear is that something that is rated 15 amps won't ever pop a 15 amp breaker. It may pull 5 amps max under actual use, or less.

I was trying to size a battery backup unit and according to the ratings on each unit, I'd need $100,000 worth of batteries to power my equipment for 30 minutes. According to actual measured load, I could get by with a tenth of that.

I don't know if it's different for table saws.

[tomwassmer]

Hey Guys. Thanks for all the feedback. This forum is great! I love the tangets we get on and the information that comes out of them. All your input is much appreciated!

[wilburpan]

Excellent, Onboard!! I do those calcs only rarely, so I have to refer to my electrical handbook. Just for information sake, most of the motors I deal with (irrigation, screw compressor, etc.), they are between about 85 and 95% efficient. I'm guessing motors like Baldor that are reputed to be built to a higher spec are in the higher efficiency range.

You can easily get efficiency ratings, along with any other spec you would need for a motor by looking at the plate. Baldor has all this information on their website, and Baldor motors have an efficiency of 85-90% in the HP ranges that most woodworkers would need.

My experience with computer gear is that something that is rated 15 amps won't ever pop a 15 amp breaker. It may pull 5 amps max under actual use, or less.

It's quite different for motors. When it starts up, the initial inrush current may be much higher than what the amperage rating says, under load it will draw close to the current listed, and when not under load the current draw will be less, but not computer equipment less.

[muddlermike]

Yes. 5hp is overkill for a home shop.