Pwk5017 Posted June 4, 2015 Report Share Posted June 4, 2015 Before I get myself into a situation where I repeatedly ask myself, "why did I do this?? why!?!?!" how much of an issue is it to swap a 3phase unisaw motor for a single? Also, is a unifence from a delta contractor saw interchangeable with a biesmeyer fence from a unisaw? Both saws are within a year or two in age. I have the contractor saw with 32" unifence, and I am looking at a 3 phase unisaw with enormous rails and the biesmeyer fence. I don't think I can fit the 84" rails or whatever length they are in my shop. Next issue is the power requirement. Looks like a 3hp single phase unisaw motor is going to cost me $300. Does this involve changing belts and pulleys and God only knows what else, or is it pretty simple plug and play with swapping motors? The price is great on this saw from 1998, but its looking like a pain in the ass to work for me. Any chance of selling the 5hp 3 phase motor and uniguard to recoup some cash? Quote Link to comment Share on other sites More sharing options...
andrew-in-austin Posted June 4, 2015 Report Share Posted June 4, 2015 Considering the cost of the 1-phase motor, and the drop in HP when converting to that motor, I would keep the 5HP motor and adding a VFD. A VFD can be powered by 1-phase 220-240v, and you then get the ability to control the speed of the motor. That would be a nice feature for certain things like cutting lexan or aluminum or other odd materials. The VFD can also control how fast the motor stops, so you could avoid the blade from spinning for a minute or so after a cut. You also then don't have to swap out a 50+ pound motor. To find a proper VFD, I would search for "vfd 220 5HP inverter" on that popular internet auction site. It should be about $200 with shipping.I have one of those VFDs for a 3-phase radial arm saw, and I like it very much. You also might want to search on youtube for VFD conversions to see what yo need to do for the wiring.If you decide to swap motors, then the important thing to get it to be drop-in replacement is matching motor frame size. 1 Quote Link to comment Share on other sites More sharing options...
tim0625 Posted June 4, 2015 Report Share Posted June 4, 2015 Considering the cost of the 1-phase motor, and the drop in HP when converting to that motor, I would keep the 5HP motor and adding a VFD. It should be about $200 with shipping. $200...maybe that's what you can get it at an auction but I bought one new for my wood lathe that would handle just a 2HP motor and at a discount it's over $300...about $345. VFD - 5HP Quote Link to comment Share on other sites More sharing options...
Pwk5017 Posted June 5, 2015 Author Report Share Posted June 5, 2015 Hmm, you have me thinking about the VFD for once. I just cant help but feel like that setup would be so jury rigged. I know a lot of people do it successfully, but it just seems chincy to me. I am seeing if I can get the new motor for $200, and if I can then I think I will just go that route. Still trying to decide if $800ish at the end of the day is worth it for a rigged 20 year old saw. I suppose even then its about half off a new grizzly cabinet saw, so it seems fair and worth the effort. Quote Link to comment Share on other sites More sharing options...
tim0625 Posted June 6, 2015 Report Share Posted June 6, 2015 I've never switched out a table saw motor but the whole VFD thing for a TS is a bad idea IMO because of the expense and the use - its main function is to sort of replace a phase convertor and to make 3 phase motors variable speed with an input voltage of 220v. I'd just buy a 3HP, 220V, 1 phase motor and be done with it. Getting the right rpms is math. You already have the pulley on the saw. Get the right on for the new motor and go make dust. Quote Link to comment Share on other sites More sharing options...
Tpt life Posted June 6, 2015 Report Share Posted June 6, 2015 I think this is a law of diminishing returns. A quality and properly engineered conversion drive or even three phase service may be worth it if you have a commercial atmosphere to draw from. I have three phases on poles in my back yard. There is big industry just across the tracks. I could likely get service for the cost of a dedicated transformer (since my neighbors would not have a reason to share.) I would never do that here. Why? One tool does not warrant the cost. I live in a commercially rich environment. I could get "cheap" used three phase equipment all year round. The problem is that my small lot does not support the space needed for these tools that are made to work hard and generally have a larger foot print. I won't poo-poo anyone who wants to tinker with VFD, but that ends up becoming a hobby of its own in many cases. The tool setup can also become its own hobby. You need to weigh the fact that neither saw will carry a warranty anymore, so any change you make that causes a problem is yours to fix. This does not scare me off of everything, but I paid for a new saw recently because I saw money going down a hole with an older saw. This is not intended to be comprehensive or even to sway you, but rather is an attempt to help frame some of the other issues. Quote Link to comment Share on other sites More sharing options...
wdwerker Posted June 6, 2015 Report Share Posted June 6, 2015 20 year old saws don't have any warranty left. The current owners of Delta do not even support the older machines with parts. I love my 2 UniSaws but would hesitate to buy one today. Quote Link to comment Share on other sites More sharing options...
tim0625 Posted June 6, 2015 Report Share Posted June 6, 2015 Yeah, the VFD on my wood lathe is great but I chose to go that direction because it's the way to slow down the rotations without going with stepped pulleys and you can make fine adjustments in the speed. For applications where rpm adjustments are needed, I wouldn't hesitate to pick up a 3 phase motor and pair it with a VFD but the problem is that VFDs are sized and are purchased by the maximum horsepower of the motor you are pairing it with; so as you get into higher HPs, the VFDs get pretty expensive - like Shaffer said, law of diminishing returns and for a Table saw, you just need it to run at one fast speed....heck on my lathe, I sometimes chuck up a round piece of wood and tie my fishing line on it to take it off of a fishing reel.....just dial in the speed you've comfortable with and voila....one day, i chucked up a piece of wood, spun it slowly, and simultaneously sanded it with a flap disc in the 4 1/4 grinder so VFDs the the right application are great! Quote Link to comment Share on other sites More sharing options...
Pwk5017 Posted June 6, 2015 Author Report Share Posted June 6, 2015 Cripes, you guys have me really second guessing this purchase now. I worked a deal with another guy to swap him the used 5hp 3 phase motor for a new 3hp single phase motor and $200. Looks like the unisaw with bies fence and uniguard is going to be $500. I planned on selling the uniguard if I can as well, because I have an excalibur guard. So, I am looking at roughly $600ish for a brand new motored 20 year old saw. For all intents and purposes, I was under the impression this was a screaming deal. I know when all the "i need a saw for $500" threads pop up everybody tells the guy to go get a used cabinet saw. Ive never seen a single phase cabinet saw for under $1000, let alone $500. $500 from what I have seen will buy you an ancient rockwell unisaw from the 40s or 50s. What would potentially break on me that I would be screwed over? If Im starting with a new motor and belts/bearings are easy to come by, what else could go wrong? I dont know a ton about internal workings of saws to fathom a guess. Im going in with the impression that this saw actually isnt that old considering what it was made for. Im assuming this one will tide me over for the next 3-5 years, and that I shouldnt expect any mechanical issues at all over that time frame. I was with a local woodworker 2 months ago who was bitching about finding parts for his PM66, so I expect to experience part issues with any used cabinet saw. Can the three phase switch be used with a single phase motor? That is one potential cost I havent factored int. Also, how hard of a task is it to replace the arbor bearings on this saw? I figured I should replace those and the belts when I swap motors. Quote Link to comment Share on other sites More sharing options...
Tpt life Posted June 6, 2015 Report Share Posted June 6, 2015 So with regard to the deal....the deal is not bad if you get what you expect. I think we see some of these questions repeated quite often and realize that all kinds of backgrounds come into play. There is also a big difference between grandpas Unisaw and three phase post production machine. Replacing the bearings in your cost equation makes good sense. The motor swap sounds like a good deal. See what he pulled the motor from and see if you can swap switches if you like, but I would not consider a new switch purchase to be a put off. I would certainly consider a Unisaw at that cost. I truly did not mean my other post to be a nay say. Quote Link to comment Share on other sites More sharing options...
andrew-in-austin Posted June 7, 2015 Report Share Posted June 7, 2015 It sounds like a good deal. Just make sure the motor is a drop in replacement and has the same pulleys (three of them on there?). I would suck to buy the saw and swap motors and find out the motor wont fit. Quote Link to comment Share on other sites More sharing options...
tim0625 Posted June 7, 2015 Report Share Posted June 7, 2015 Yeah I'm with Shaffer...don't mean to be a nay say...sounds like it could be a good deal. On table saws, there aren't a lot of parts to wear out - motor belt and bearings mostly. I'm not sure if the same switch will work - probably won't but a new one is $40 and if you look around, you can get it on sale for $24.99 Quote Link to comment Share on other sites More sharing options...
Pwk5017 Posted June 7, 2015 Author Report Share Posted June 7, 2015 Yep, the new motor is actually a delta branded motor. Apparently some amish man purchased a unisaw, but didnt want the electric motor, so the shop kept it. This shop then went out of business and the person I am swapping with purchased the unused motor. It has sat in his shop for 10 years, and hes been trying to sell it for a few months I think. I might be wrong, but from what I have read while searching, you can use the same right tilt motor on all unisaws from the 40s till about 2008 when they released the newest design. This motor has the 3 belt pulley on it to, so I am pretty confident that it is a match for the 3 phase machine. I dont feel like you guys are being nay sayers at all. It's a semi-complex situation that you all are keeping me honest on. By replacing the motor, switch, belts, and bearings it looks like I am going to be at exactly $800 for a rehabbed machine. Then, if I can get lucky and sell the uni-guard that would only sweeten the deal. Also subtract what I am selling my contractor saw for, and I am pretty excited about the saw upgrade for a few hundred bucks. Is there a fail safe way to test arbor bearings? If I didnt have to replace those, this would be a much easier process. Swapping the motor and belts seems easy with two guys. Taking apart that arbor assembly and hammering on and off bearings is the semi-daunting task at hand. I might get lucky and the shop will have replaced the bearings already in the last few years. I imagine there is routine annual maintenance on machines in pro shops. Quote Link to comment Share on other sites More sharing options...
Tpt life Posted June 7, 2015 Report Share Posted June 7, 2015 Fail safe....no. There is usually some run out play or noise while running even at no load. You can take a mechanic's stethoscope to them as a diagnostic also. Quote Link to comment Share on other sites More sharing options...
Trip Posted June 7, 2015 Report Share Posted June 7, 2015 ==>switch Many 3p mag switch setups can be wired for 1p operation. This is, of course, most common when a machine can be purchased with either motor as an option -- hint hint... The two diagrams are usually in the manual... If not, I'm sure the internet can provide the wiring... It's a fairly common to purchase used small 3-5HP 3p comercial kit for home hobby 1p use... Assuming you trade the motor, you can usually net-out around $200... This is almost always the best way to introduce smaller 3p kit into the home hobby environment... Quote Link to comment Share on other sites More sharing options...
Pwk5017 Posted June 9, 2015 Author Report Share Posted June 9, 2015 Whelp, I purchased the saw yesterday. $400 and free delivery to my house. I had my pick of the lot, and felt like I purchased a saw in pretty great shape. Atleast, it looked to be in good cosmetic condition. I wasn't able to take things apart enough to get a look inside the cabinet. The blade adjustment wheels seemed a little stiff, but I will attribute this to sitting unused and unlubricated for a year or two. I should have pics tonight, and it will be time to yank the motor so I can trade it for the single phase. Yesterday was also the first time I lined up 3 CL deals in one day. Purchased the unisaw on my lunch break, bought an Excalibur blade guard/dust collection for $150 immediately after work, and then sold my 20 year old delta contractor saw for $400 around 8-9pm. I think I need a self-imposed timeout from CL for a bit, Triple, you confused me, but the takeaway message for me is, "it should be able to be changed to single phase", which is what I wanted to hear. Is this a difficult operation to perform? My dad is an electrician, and I wired my own shop, but following wiring diagrams for motors/switches will be a first for me. Quote Link to comment Share on other sites More sharing options...
ponderingturtle Posted June 9, 2015 Report Share Posted June 9, 2015 I've never switched out a table saw motor but the whole VFD thing for a TS is a bad idea IMO because of the expense and the use - its main function is to sort of replace a phase convertor and to make 3 phase motors variable speed with an input voltage of 220v. I'd just buy a 3HP, 220V, 1 phase motor and be done with it. Getting the right rpms is math. You already have the pulley on the saw. Get the right on for the new motor and go make dust. As long as you run the VFD at 60hz you will get the right speed out of the motor. Quote Link to comment Share on other sites More sharing options...
Trip Posted June 9, 2015 Report Share Posted June 9, 2015 Sorry for the confusion... Much small 3p woodworking kit can also be ordered as 1p. To simplify product configuration, many of these saws use a magnetic switch that can be wired to drive 1p or 3p motors... Not that the motor can be rewired in that way -- well, you can hot-rod it, but that's another thread... The point is, if you swap the motor for 1p, you may may not need to purchase/mount a new set of controls... Many operator's manuals show the wiring for both sngle a three phase wiring... An electrician should certainly be able to read the wiring diagram... The best 3p conversion is to purchase a 1p motor and sell the 3p to recoup the investment... The differential spend will be a couple hundred bucks... Unless we are talking an unusual motor mount, the swap is straight forward... Assuming you can reuse the controls, for a couple hundred bucks and about an hour investment, you can be done with it... Quote Link to comment Share on other sites More sharing options...
ponderingturtle Posted June 9, 2015 Report Share Posted June 9, 2015 Yeah, the VFD on my wood lathe is great but I chose to go that direction because it's the way to slow down the rotations without going with stepped pulleys and you can make fine adjustments in the speed. For applications where rpm adjustments are needed, I wouldn't hesitate to pick up a 3 phase motor and pair it with a VFD but the problem is that VFDs are sized and are purchased by the maximum horsepower of the motor you are pairing it with; so as you get into higher HPs, the VFDs get pretty expensive - like Shaffer said, law of diminishing returns and for a Table saw, you just need it to run at one fast speed....heck on my lathe, I sometimes chuck up a round piece of wood and tie my fishing line on it to take it off of a fishing reel.....just dial in the speed you've comfortable with and voila....one day, i chucked up a piece of wood, spun it slowly, and simultaneously sanded it with a flap disc in the 4 1/4 grinder so VFDs the the right application are great! If you set it up with a 3 phase plug you can get 3 phase equipment and run it all from the one converter. This could save money. So you can use the VFD for the lathe, the table saw, drill press and so on. Quote Link to comment Share on other sites More sharing options...
drzaius Posted June 9, 2015 Report Share Posted June 9, 2015 Sorry for the confusion... Much small 3p woodworking kit can also be ordered as 1p. To simplify product configuration, many of these saws use a magnetic switch that can be wired to drive 1p or 3p motors... Not that the motor can be rewired in that way -- well, you can hot-rod it, but that's another thread... The point is, if you swap the motor for 1p, you may may not need to purchase/mount a new set of controls... Many operator's manuals show the wiring for both sngle a three phase wiring... An electrician should certainly be able to read the wiring diagram... The issue you may have with trying to reuse the existing 3 ph mag switch is that the coil is going to be 208V, which means that you can't use it with 120V single ph. It must be 240V. You also need to make sure you connect to the correct 2 poles of the 3 pole switch in order for the control circuit to have power. Quote Link to comment Share on other sites More sharing options...
Trip Posted June 9, 2015 Report Share Posted June 9, 2015 I've never checked all my kit, but the latest few arrived with terminal lugs only -- all were 1p and 3p and the box came with diagrams for both... I've never wondered how they manage the coil -- two taps??? Next time I've got to wire something, I'll take a look... I bet the answer is something quite simple... Quote Link to comment Share on other sites More sharing options...
Pwk5017 Posted June 10, 2015 Author Report Share Posted June 10, 2015 Alright, finally have the saw in my possession! It was actually pretty easy to get this thing off the box truck with 3 guys. Put it on a mover's dolly and wheeled it into my garage. Took me an hour and a half to disassemble everything off the saw except the table and interior components. Saw was a lot lighter without the motor! I have a few questions. One, the guy im swapping motors with now requested the switch and control panel thing on the back. What is that panel on the back, I have never seen something like that on a tool. Is it specific to 3 phase power? He offered up a new 220v switch in exchange for my 3 phase switch and rear panel. If this stuff is of no use to me, then I don't mind trading it, but I have no idea if its useful to me or not. Does it have value that I should leverage in the deal? The saw only has one cast iron extension wing, is it worth trying to buy another wing off one of the other saws they were selling to bolt onto the right of the saw? I do like the idea of more cast iron near the blade for its flatness and durability. Also, has anyone ever taken a wing to a machine shop for them to drill and tap holes in? I have a jessem mast r slide sliding table attachment, and I would like to bolt the sliding carriage on to the wing instead of on the table in lieu of the wing. That extra 8-10" of CI is helpful for crosscutting 4'+ pieces. Unsure of who to go to for this exercise, and if I am going to pay an arm and a leg for 3 holes. Next, link belts or just replace with matching belts? Some people say the link belts are hard to get right, others like them. I have a few link belts, so I know how incredible they can be for vibration dampening. It would be a pricey decision, I think. $100+ Finally, dust collection inside the cabinet looks like it is going to suck. Atleast on my contractor saw, I had a 6" port directly under and in close proximity to the blade. I can modify the base of the cabinet to a 6" port on this saw, but im still 3 feet from the blade. While I was disassembling the saw, I noticed a vertical metal attachment bolted directly in front of the blade. It looked like a deflector of sorts to force the sawdust downward toward the ramp. I believe this deflector tilts with the blade. Is it possible to buy a blade shroud for a G1023 and bolt it into position using the deflector's bracket? Is there a newer delta shroud available that would work? I have an Excalibur blade guard for the top of the saw, and a blade shroud in the cabinet would make my dust collection extremely effective for this saw. I have a 3hp grizzly cyclone with 7" spiral duct with 6" flexible hose to most/all machines. Quote Link to comment Share on other sites More sharing options...
Trip Posted June 10, 2015 Report Share Posted June 10, 2015 ==>What is that panel on the back, I have never seen something like that on a tool Photo please Quote Link to comment Share on other sites More sharing options...
Pwk5017 Posted June 10, 2015 Author Report Share Posted June 10, 2015 ==>What is that panel on the back, I have never seen something like that on a tool Photo please Not my saw, but this is what it looks like. The switch and motor connect to this panel. I assume this panel is then hard wired to a power connection. Quote Link to comment Share on other sites More sharing options...
drzaius Posted June 10, 2015 Report Share Posted June 10, 2015 The panel is probably a magnetic starter. 3 ph motor needs one, but it'll work on a single phase 240V motor (not 120V without changing the coil). A mag starter is nice because if there is a power failure the saw shuts down & stays that way when the power comes back on. Re link-belts: I put one on my contractor saw & it made a tremendous difference in vibration and belt slippage. On the jointer there is noticeably less vibration. But on the drill press, no difference that I can tell. My experience only. Quote Link to comment Share on other sites More sharing options...
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