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Joe Hillmann
01-02-2013, 4:10 PM
I have an older (from the 80's) craftsman tablesaw. It isn't a high end machine by any means but it is the best I have ever owned buying a new one won't happen any time soon.


It has a 1 hp motor on it and when ripping oak it bogs down a bit, and I may be doing a lot of ripping if my current project turns out profitable.

Is there any reason I shouldn't put a larger motor on it. As long as it is the same or close to the same speed will the bearings on the saw handle it?

Also the motor that is on the saw at the moment can also be rewired to 230 volt. If I were to convert it to 230v would that make it more powerful Or just more efficient?

Jeff Duncan
01-02-2013, 4:31 PM
I can't answer your question as to how much motor your bearings can handle, but generally speaking entry level machines are not designed with a whole lot of extra capacity. Going from a 1 to a 2 hp motor may work OK....may not? Remember that you'll likely also have to replace the electrical if you upgrade the motor, so if your buying a motor too, your costs are going to start adding up. Plus your putting money into a machine that very likely will not return that investment when it comes time to sell. All that said at some point you may want to re-consider a used cabinet saw.

In the meantime I'd recommend looking at your blade and maybe investing in a new good quality designated rip blade, or if your using one already, having it sharpened. Also, utilizing a short fence will lessen the sideways stresses on the blade you can get from ripping. A couple of things that may get you by with the saw you have to get you profitable so you can invest in.....

good luck,
JeffD

Mike Henderson
01-02-2013, 4:44 PM
I put a 2HP motor in a Craftsman table saw and it worked fine. There's only one belt and the tension is just the weight of the motor so in really hard cutting the belt can slip. Also make sure you can tilt the full 45 degrees with the new motor.

To answer your question about 120 or 240V operation - if your 120 circuit is properly sized, converting to 240V will not make any difference.

Just keep your old 1HP motor and when you get rid of the saw, put the 1HP back on it and save the 2HP for some future use.

Mike

Joe Hillmann
01-02-2013, 4:44 PM
I don't plan to spend any money on the saw, I already have a 2 hp motor sitting on a lathe that I don't use. Although I may have to look into a better ripping blade. I know that the last time I bought blades I bought a good cross cut blade but I don't know much about the quality of the rip blade I have other than it has all its teeth.

Carroll Courtney
01-02-2013, 4:51 PM
Over the yrs I have seen some very nice furniture,cabinets beening made on a Craftsman table saw(not by me)there is no shame in using that saw making quality projects.So I say if thats what you want go for it,but maybe invest in a good ripping blade not one from HD before I change the motor,wiring,etc---Carroll

Jim Andrew
01-02-2013, 5:09 PM
I used to have a craftsman table saw, it was older than yours, but similar. When I wanted to rip I would have to put on a blade of smaller diameter, used 8 & 9" blades, now if you had a freud with about 24 teeth, you would be amazed what you could rip. My old saw benefited from switching to 220, but the old motor was so worn out, that I got in the habit of taking a stick and turning the blade to get it to start. First I looked at getting a new motor and a new fence, figured out it would be about as expensive as just getting a new saw. So at the time found I could get a Uni for 1000, so went that way.

Bruce Page
01-02-2013, 6:19 PM
I had a mid 80’s Craftsman TS. IMO, if you have a lot of ripping to do your first step should be to invest in a good ripping blade like the Freud thin kerf LU87R010. It will make a big difference in your Craftsman’s performance.

Wade Lippman
01-02-2013, 7:58 PM
I bought a Craftsman contractors saw with a upgraded 2hp motor on it. It worked fine, but was physically too big and interferred with the wood. So, make sure it will fit properly or its probably not worth it.
The guy who said it might be too much motor for your bearing might be on to something; my upgrade was 1.5 to 2.

Bruce Wrenn
01-02-2013, 9:44 PM
First, let me address the bearing issue. Most likely the Craftsman uses 6203 bearings on the arbor. These are the same bearings found on a Delta contractor's saw and a UNISAW. When I had my Craftsman, I added a Century 2.0 HP motor (NEMA 56 frame size.) I took the motor mounting bracket and reversed it so it was open to about 90 degrees to support rods. Forget about that cute little arc for adjusting tension on belt. Gave the saw away (with original motor), but kept Century motor for my then, new to me, Delta Contractor's saw.

david brum
01-03-2013, 10:10 AM
I applaud the idea for squeezing more capacity out of your machine. Have you checked the rpm on your lathe motor, though? Most are in the 1750 range, whereas most table saws are around 3450 rpm. That means you'd have to double the size of the drive pulley. You might need to make sure there aren't additional clearance issues and/or excessive wobble issues.

Bill Huber
01-03-2013, 10:27 AM
I had an 8" Craftsman with a 3/4 hp motor on it and used it for a long time, I cut 8/4 hard maple and purple heart with it without a problem. I did use a thin kerf blade and the feed rate was slow but it worked fine.

I now have a Jet with a 1 1/2 hp and with a full kerf blade I cut 8/4 all the time.

Bottom line is I really think you need to look at the blade, get a good thin kerf blade and I think you will see a really big difference.

Howard Acheson
01-03-2013, 11:07 AM
Are you referring to a Contractor Saw where the motor hangs off the back of the cabinet? Or, is it a true Cabinet Saw where the motor is inside of the cabinet?

The reason it's important is that you don't want to add any weight to the motor assembly if it is a Constractor Saw. On Contractor Saws, the the weight of the motor is carried by the table itself. More weight can easily cause the table to warp. With true Cabinet Saws, the weight of the motor is carried by the enclosure box, not the tabletop so additional weight will not have much affect.

Rewiring will not affect the performance of the motor. All convertable 120/240 motors run on 120 volts internally. There are two coils each running 120 volts and using 1/2 the 120 volt amperage (The coils act as a resistance and split the amperage). All you do when you re-wire the motor to run on 240 is change the wiring connecting of the coils from parallel to series. When wired for 240 volt operation, one 120 volt leg and its associated amperage is routed to each individual coil rather than a single 120 volt line providing 120 volts to both coils. The same voltage and amperage runs through the individual coils no matter how it it wired. It is amperage that creates heat, and because the amperage in each coil is the same for both wiring configuations, there is no difference in the heat produced by either wiring configuation. The motor is perfectly happy with either voltage and doesn't even know you made the change.

The only advantage to re-wiring for 240 is that it reduces the amperage in shop wiring running from the breaker to the wall outlet. This means that the voltage drop in the wiring is lessened. If your wiring is properly sized for the amperage and run length, voltage drop will be minimal and well within the operation range of any good motor. Voltage drop will be almost equal if the wire size is the required size for each different motor amperage. Only if your wiring is inadequate for the higher amperage of 120 volts will the motor run better when you convert it to 240. In this case, upgrading the 120 volt wiring one size and making it a dedicated curcuit, will accomplish the same as installing a 240 volt circuit and wiring the motor for 240.

If a motor is coming up to speed very slowly or is tripping a breaker during start up or when under normal load, you either have other loads on the circuit, or the circuit is undersized for the amperage or the run length. The fixes are: remove the other loads from the circuit or upgrade the circuit. To upgrade the circuit, either rewire with heavier wire and a larger 120 volt breaker, or convert the circuit to 240 volts which has the affect of lowering the wiring amperage draw. Either of these solutions will equally fix the problem. Again, the motor doesn't care and won't perform differently as long as it gets clean power.

Carl Beckett
01-03-2013, 11:19 AM
A nice simple article on some motor basics:

http://www.greenheck.com/media/articles/Product_guide/motorarticle.pdf

Bryan Cramer
01-03-2013, 12:08 PM
I did the same for my dad's old Craftsman. I had a 1.5 hp pressure washer motor laying around so I put it on the saw. It works alot better than the 1 hp motor and it is still wired to 110V.I now use the saw as a dedicated ripping machine. I have ripped 1200 linear feet of 2X pine in one morning. I also got more power when I added slightly (1/2") larger pulley at the arbor. This slowed down the arbor speed, but I never noticed a drop in performance. The blade was a 24 tooth Freud Diablo thin kerf. A thin kerf blade makes a difference too.

Joe Hillmann
01-03-2013, 2:21 PM
The old motor is 3400 rpm the new one is 3600 so that wont be a problem but due to the weight of the larger motor I don't think the saw will handle it without doing a lot of redesigning of the mounting hardware.

When I took a closer look at the way the motor mounts to the saw I found that the weight of the motor that is on the saw now has bent the mount so I don't think adding 3 times as much weight to it will be a good idea. I think I will just settle for a better blade and see what happens.

Tom Esh
01-03-2013, 3:16 PM
I'd suggest trying a thin-kerf blade if you haven't already. It's the equivalent of adding ~25% hp.

Ole Anderson
01-03-2013, 11:37 PM
I had a Craftsmen 6" belt/disk sander combo with a 1/2 hp motor on it. Never used the disk so I removed it. Did some serious production work on aluminum on the 6x48 belt though. I could hog it down too easily so I replaced it with a 1 hp TEFC from Grainger. Still going strong 20 years later.

mike calabrese
01-04-2013, 11:21 AM
i have a Craftsman table saw from the early 70's what we did many years ago to soup it up was to add a slightly larger sheave (pulley) on the motor to kick up the RPM some.
I don't remember the exact up size but i would guess knowing me @ 20% speed increase to @ 4200 rpm = More cuts vs your usual feed speed.
Look beyond the blade

No 1 get a quality carbide rip or combination blade....life and limb will be so much happier with a quality, brand name blade, thin kerf blades are OK but will require greater attention to point no 2 .

No 2 the old Sears / Craftsman saws were not the best built and assembled. Make sure , starting with a quality blade or a good and true sanding disc that you have the rip fence honestly parallel to the blade especially wih a thin kerf blade.

No3 be sure your saw is solidly footed against the floor. A soft foot or a foot that is unevenly loaded with increase the vibrations in the machine that will ultimately show up in the wobble at the blade and in your work piece adding to the distress with long rips .

Ron Kellison
01-04-2013, 12:20 PM
In addition to putting on a good thin-kerf ripping blade (Freud Industrial series, Systematic, Infinity are all affordable) I would suggest changing out your belt to a link belt. I did this on my old Craftsman 1-HP and it made a noticeable difference in power transmission. It also reduced the vibration significantly.

Ron

steven c newman
01-04-2013, 12:21 PM
I also have an 80s 113 EMERSON Craftsman tablesaw. Bought it new, in box, no less, at Sears. After a lot of hard use, trunion cracked, Sears wanted $80 to ship a new one from Texas. Checked with the Construction Company I was working for at the time, they were scrapping out a similar saw, as they were going to Deltas ( which turned out to be POS) Took the "scrap" saw home after paying $25 for it. Swapped bad and broken parts out, for good parts, and kept all for wings. 250170250171250172It has a bigger motor, with dual pulleys. I THINK it's a 2hp, and it still is a 120v motor. Whenit does start to bog down, I change blades. Need to buy some new ones this spring. Been running decently the whole time. And, I can even crank it over ( takes awhile) to make 45 degree cuts. Fence is a replacement, Sears sent someone out to replace the first one, due to a warp in the middle. "New" one is flat, and straight. Nice wide top, too. original saw=$400.00+ replacement parts=$25= a decent saw, i think. I can even set a nickel on the top while the saw is on. And, it stays put.

John Piwaron
01-05-2013, 10:13 AM
I had one of those saws - a Craftsman contractor's saw with a cast iron top and the cast iron lattice extension wings.

It worked fine for me. After I replaced the fence. The original fence is junk. With no offense to actual junk. I got a Biesemeyer homeshop fence for it. It turned a so-so saw into a reliable accurate friend.

A thin kerf blade helped a lot. As did a link belt. But through it all, the motor remained the same. I cut a lot of hardwood with it including 3" thick hard maple. Yes, it want slow. And if not properly aligned it would bind and burn.

The motor hangs off the back and tensioned itself by it's weight. That could cause it to slip during hard cutting. But mostly it worked o.k. Were I to have replaced it my plan was no more than 1 1/2 to 1 3/4 hp. Remember, the saws that use high horsepower motors also use 2 belts.

It's gone now. I know it's on it's 2nd home. I sold it to a friend and got a hybrid to replace it. I recently sold the hybrid to the same friend who in turn sold the Craftsman to someone else. It's still working fine.

scott spencer
01-05-2013, 1:37 PM
Ditto on getting a good 24T thin kerf ripping blade....that, and good alignment/set up should make a big difference.

A 2hp motor should be fine if it'll fit physically, has the correct RPM, duty rating, similar weight, etc. I wouldn't go any larger than 2hp though. If you've got 220v, I'd switch it. It's not a matter of there being more power, or even more efficient, but your 110v circuit is more likely to suffer from voltage loss due to being undersized, shared, etc. 220v splits the amperage between two hot legs, and is almost always dedicated to one appliance. If you don't have 220v, it's probably not worth rewiring unless lights are dimming and/or the saw comes up to speed slowly.

Bruce Wrenn
01-05-2013, 8:40 PM
Jerry Cole uses a Craftsman saw to demonstrate the Dubby at the Woodworking Shows. Most never notice that he is using a Sears saw.