I am thinking of adding variable speed to my Conover wood lathe. Right now I have a surplus 1/2 hp baldor motor hooked to a 4-step pulley. The power isn't enough for very fast turning of anything much over a few inches in diameter. I could find a 1 or 1-1/2 hp motor but haven't , and new ones cost about $300 or more. At that price I might as well do it right. I am looking at putting on a 2hp 1725 rpm Baldor 3 phase motor with a variable frequency drive (240 v input, 7 amp 3 phase output), to get nice power and variable speed. Baldor Model # of motor EM3558, and of the VF drive is VS1ST82-0. An alternative is a DC motor with a DC drive but this costs more than the 3phase AC/VF drive combination. Curious if anyone has experience in this area and also if there are other Conover Lathe owners out there.
Haven't added one, but did buy one with a 1 1\2 HP and VFD. Plenty of power and torque through all speed ranges. Beats the devil out of step pulleys.
I've an old Oliver No. 19 that has a variable speed drive built in. Very handy .... when I use it. :)
A vfd running a 3 phase motor is the only way to power a lathe...or a lot of other machines. You do loose some torque at low speeds so pulleys are useful to get in the right range. The vfd can also run the motor faster with the limiting factor being how much speed the motor bearings can stand.
My experience has been with the TECO FM-50's. Only reason is that model seems to be the most popular with woodworkers.
Two places to buy that I have used.
http://www.dealerselectric.com/ They seem to have the best prices and sometimes also have NOS with warranty.
Factorymation (http://www.factorymation.com/s.nl;jsessionid=X2gGMJmPy19pSJNJvrxPQL51nmlFJ62P2lgTGJgv15w81gNyfsYkxYvtPykFj8NBhv5JLvl49Zv3JCcphMjvTWTLh9p1cTwYc0TnR6QLvknnYnyy7dLWMvd7rtp9kVGT!-1517549075?sc=2&category=11) seem to have the best technical support.
3 phase motors are simple and a lot of times can be found used at bargain prices.
I'm still learning about vfd's but think I have nuff knowledge I can anwser questions if ya have any.
If you go with a DC motor, you always have the problem of the carbon brushes.
Yes, thanks about the DC brush maintenance and for the other tips so far. Looks like I could get a TACO FM50 for 2hp for less than $150. Seeing a lot of used Baldor 2hps at less than $100 incl shipping on EBay and found a new one M3558 for about $230 plus shipping. Would be great to find a used one in a pile somewhere local for free or a few bucks with no shipping but that takes time and effort. Just need to find some places to look and give this a few weeks to settle.
My old lathe had belts.
The new one, DVR-XP by Teknatool out of New Zealand, is computer controlled, from 100 rpm up to 3600 with 5 presets, and a reverse button (after stop- with screen warning). It will sense a big catch and drop power in a rotation so is pretty safe.
I can't imagine ever going back........
Quote from: Lud on September 18, 2010, 04:45:28 PM
My old lathe had belts.
The new one, DVR-XP by Teknatool out of New Zealand, is computer controlled, from 100 rpm up to 3600 with 5 presets, and a reverse button (after stop- with screen warning). It will sense a big catch and drop power in a rotation so is pretty safe.
I can't imagine ever going back........
Is there any danger of a chuck or faceplate unscrewing when you run it in reverse?
My chuck and face plates have locking set screws and the only time I've run in reverse is sanding. Hasn't come off yet.
Confirmed. Only use reverse for sanding and finishing. No cutting.
It does make a huge difference on the finish you can achieve. The sand paper grabs the wood pores in two directions. Round stuff has pores going every whichaway! The progression thru the papers makes a smoother surface by alternating directions.
I like to blow the dust out of the turning very carefully before putting on the mineral oil..it's dust, i.e. crud inside your art! I apply the oil at very loww rpm..going both directions as pressure and heat give you uniform saturation and then the beeswax.....both directions again with a nylon finishing pad and then cotton Tshirt for a fine shine!
It's quick with the right equipment . ;)
Do you know of your variable speed lathes have electric braking when stopping or slowing down? One can get in a VF controller a transistor option that runs an optional resistor pack to get dynamic braking, both are at extra cost. Probably not the right spirit to be in a hurry after all turning is supposed to be fun but it would keep your hands off the turning work and probably would be a nice feature with a lot of starting and stopping.
Quote from: terrifictimbersllc on September 19, 2010, 06:47:16 PM
Do you know of your variable speed lathes have electric braking when stopping or slowing down? One can get in a VF controller a transistor option that runs an optional resistor pack to get dynamic braking, both are at extra cost. Probably not the right spirit to be in a hurry after all turning is supposed to be fun but it would keep your hands off the turning work and probably would be a nice feature with a lot of starting and stopping.
Can't tell you about all the options, haven't read all the manual that came with the lathe and it's been so long since I programed the VFD I put on my mill, I would have to go back and re-learn the process. I can tell you I remember programing the thing to stop, rather than slowing to a stop.
You can program the TECO FM50 for braking...anywhere from a little to a lot. The resistor option would only be required for some unusal machine.
My 20" bandsaw used to run forever when turned off. It has a manual foot brake to get it stopped. I programed the FM50 for braking and never touch the foot brake anymore.
The concern of things coming off is valid with some machines. A grinder comes to mind.
Most lathes have a hand disc/plate? that slides thru your hand that brings the turning to a full stop. Heck, after the turning's smooth I'll just put my hand on it to brake it after hitting the OFF button. I even turn with gloves on all winter despite some folks safety concerns which are based on lathes lacking state of the art controls. I mean I appreciate what could happen IF I was using my old lathe and tried it. Sheesh! :o :o
Thanks again for your comments which helped me to decide to get a VF drive and 3 phase motor. I ordered a Baldor EM3558 2hp 1725 rpm 3 phase motor and a Toshiba VFS11S-2015PL-W VF controller, which has a knob speed control on it. It has some programmable braking on its own and is also "resistor ready" if one wants to add a resistor to help slow down larger loads faster. Will wait to see if that is necessary. Will add a manual foot switch in series with a reversing switch when I set it up. Have to look at adding a set screw or something to keep my faceplate and Stronghold chuck from coming off in reverse, maybe not necessary but the thought scares me. Going to take about 2 weeks to get the stuff. Pontiac Electric in Pontiac Michigan had great prices and Tony there was very helpful. thanks again i'll post about it later.
Got the new motor today! I don't think I will be stopping the lathe anymore with a turning tool! Still waiting for the VF drive. Here's my current setup, the lathe pulley cover is removed for clarity. That's a Stronghold chuck on the right and a 4 step pulley on the left and in the back. The Baldor 1/2 hp came out of the trash somewhere but I never detected anything wrong with it. Served me well for about 18 years or so mostly spindle turning.
(https://forestryforum.com/gallery/albums/userpics/21495/2822/lathe-3.JPG)
Here's the new motor!
(https://forestryforum.com/gallery/albums/userpics/21495/2822/lathe-1.JPG)
3 phase 2HP 1760 rpm TEFC inverter ready, 208-230/460V input. Will be running it with the VF drive putting out 240V 3 phase from 240 V 1 phase input. It is a "Premium Efficiency" Baldor EM3558. The sticker on the shipping box looked like ones you see on the refrigerators at Sears, said it costs only $1500 per year to run it all the time at 10 cents per KW-h. Probably won't do that, I need to stop and sharpen tools once in a while! 8) 8)
Update, still waiting for the VF Toshiba drive. A new shipment to the manufacturer was held up in customs. Should have it in a week.
One of my cousins had all of his machine tools set up with VS all lathes and bridgeports set up to run from full speed to a stop and back up with the turn of a knob . everything was 3ph. neat set up but over my head.
Well, finally got the Toshiba VF controller the other day and got it installed yesterday. Will post pix and details separately when I get a chance. What a difference turning with 2hp variable speed compared to 1/2hp step pulley. Big help just dialing up the speed as blank gets round and then more as bowl shape nears completion.
Only thing stopping it is if the belt slips with a heavy catch (jam) in end grain. The motor rests on its own weight on the belt and pulley (Conover design). Can prevent that with some fine tuning probably.
This Toshiba drive has a couple dozen low voltage contacts inside to support dozens of functions. Even has a network cable. Yet out of the box installed I'm able to use it without any programming for forward VS turning using the knob to dial up the speed.
Toshiba used to make a solid VFD and probably still do.