Using A Larger Motor in a Table Saw

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by mainelysam posted 02-23-2012 07:19 PM 1544 views 1 time favorited 9 replies Add to Favorites Watch
View mainelysam's profile


8 posts in 2465 days

02-23-2012 07:19 PM

I’ve got a question: is it safe to use a larger HP motor than what the piece of equipment came with? For example, if a table saw originally came from the factory with a 3HP motor, would it be safe to use it with a 5HP motor? What about 1.5HP to 2 or 3 HP?

9 replies so far

View Don W's profile

Don W

18990 posts in 2743 days

#1 posted 02-23-2012 07:26 PM

I’ve done it on a few pieces, TS, shaper etc. Make sure the speed is fairly close.

-- - Collecting is an investment in the past, and the future.

View DIYaholic's profile


19667 posts in 2851 days

#2 posted 02-23-2012 07:31 PM

Having never done it, IMO, It really depends on the strength of the trunnions and such. I wouldn’t upgrade a cheap no name bench top TS. However, a well engineered name brand, may just use the same trunnion of it’s larger brother.

Just my $0.02

-- Randy-- I may not be good...but I am slow! If good things come to those who wait.... Why is procrastination a bad thing?

View knotscott's profile


8140 posts in 3551 days

#3 posted 02-23-2012 07:47 PM

Every situation is going to be different but I’d guess it’d be ok to use a 5hp motor in a 3hp cabinet saw (assuming the saw was really 3hp and made for 3hp).

It should also be ok to go from 1 or 1.5hp up to 2hp, but my guess is that a 3hp motor is pushing the limits of the pulleys, bearings, trunnions, etc., that were never made to handle tho stresses and torque from a larger motor. Be sure the motor is physically a similar size.

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View mainelysam's profile


8 posts in 2465 days

#4 posted 02-23-2012 09:50 PM

Awesome, thanks for the good feedback from everyone. This is generally what I figured as well. I am looking at a few hybrid saws that have table mounted trunnions due to the fact that they’re generally less expensive, but most are also only 1.5HP. I don’t have any direct need to upgrade to a bigger motor, but was just curious if I for whatever reason wanted to upgrade in the future. Again, thanks for the very insightful and helpful .02 cents.

View Danpaddles's profile


573 posts in 2488 days

#5 posted 02-23-2012 10:05 PM

The extra weight, and torque, is liable to mess with your fine adjustments on that hybrid. I rip big hard heavy stuff all the time on a contractors saw. Go slow, use a sharp blade. I thin the fellow recommending a rip blade is on to something, although I have not tried that myself, I might. A thin kerf blade will also require less power, but then you have other issues to contend with.

-- Dan V. in Indy

View MrRon's profile


5141 posts in 3419 days

#6 posted 02-23-2012 10:06 PM

The more HP you have, the better. An underpowered saw, will bog down in thick material. When it does, heat is generated; the blade will bind and either the saw will stall, or you can get a dangerous kickback. HP means safety; the power to cut through wood without burning the wood.

View mikema's profile


180 posts in 2762 days

#7 posted 02-23-2012 10:24 PM

If the trunions are not equipped to handle the heavier motor, I can see that being an issue. Most contractor TS spin the blade around 3450 RPM. Make sure the new motor spins at that speed. The additional HP and Torque shouldn’t have an affect on the arbor bearings since you would be spinning the blade at the RPMS they were designed for.

-- Mike ---- Visit my woodworking blog:

View Scot's profile


344 posts in 3572 days

#8 posted 02-23-2012 11:28 PM

Yes in certain cases. Some saws are built with with the larger motor as an option and can handle the weight and torque of the larger motor. Delta and Powermatic do this on the cabinet saws.

Most contractor saws max out at 3 hp. And most contractor saws do not use bearings, trunions , and mounts that are heavy enough to support the weight and tourque of the 5 HP motors. Remember, contractor saws are kept on the lighter side to make it easier for contractors to haul them from job site to job site. The heavier the motor, the more stress on everything, especially the arbor bearings.

The 5 hp motor on my Unisaw weighs more than most contractor saws.

-- If the old masters had power tools, they would have used them. So get off your damn High Horse.

View hhhopks's profile


654 posts in 2553 days

#9 posted 02-23-2012 11:59 PM

I woulldn’t do it, unless someone knows exactly what they are doing mechanically. As all machines, there are certain weak link supposed to take place.

If the TS model has a larger motor option, I would check out the spec of the larger motor. Also I would check to see if there is other changes required. So check the owners manual.

Blindly changing a motor with a significant spec difference potentially is a safety hazard.
I just don’t think it is worth it.

-- I'll be a woodworker when I grow up. HHHOPKS

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics