Changing Drill Press to VFD. HELP

[Jerry Hillenburg]

I bought a like new Powermatic 1150 VS serial #8615V167 in 1993 and it served me well until 2005 when the drive sheave assembly was damaged beyond repair because of a loose bolt. I patched it up and it runs, but I cannot adjust the speed and it is very noisy. It is not the most used machine in my shop, so for 7 years I have used it with no speed adjustment along with hearing protection. It does what I need it to do but it is not a joy to use.

I have decided to do something about it. I really was not interested in rebuilding so I went drill press shopping. There is NOTHING new out there under $1500 that can possibly compare to my 1150. This DP has had a gentle life in my cabinet shop - very little use. The way I see it, I have to get interested in rebuilding.

In another thread discussion ( http://www.sawmillcreek.org/showthre...68#post1949868 ) Contributor Van Huskey suggested that I change my OEM variable speed to a step-cone sheave setup making it a standard step-cone speed adjustment THEN add VFD.

PLEASE, help me with the VFD - I know absolutely nothing about VFD. What specifically do I need? Your advise will be greatly appreciated.

I have a new in the box Baldor 3hp 1725rpm 3ph motor that is the same physical size as the ¾ hp on the DP (see pictures) - will it work for my application?

[Van Huskey]

The 145T motor will fit I THINK... That is an excellent motor if it works. Don't let anyone question the high horsepower since the belt would slip before it could send all 3hp and the 1150 is built like a tank anyway. It is 1725rpm which is perfect. I would suggest the 3hp Teco 50 drive. I usually recommend factorymation but they haven't had the 3hp in stock for a while, heres one source: http://dealerselectric.com/item.asp?...ID=165&PID=737

One thing to keep in mind is you don't want to run it at low speed for a long time, the fan that provides cooling will also slow down... DPs tend to only be run for a few minutes at a time so it doesn't usually become an issue. At lower speeds the motor powered by the VFD will keep constant torque down to probably 175 RPM or so BUT HP will drop off BUT with a 3hp motor you probably will never notice an issue. By having such a high HP motor you will have far less to worry about.

At this point get the drive train worked out and make sure the motor will fit. Once this is done it will just be a matter of getting the VFD and wiring it up. You can use the on off switched wired through the VFD's low voltage auxillary circuit and I would think it was cool to put a 10k ohm pot attached to the current VS crank which would allow you to control the speed just like you always did (less effort to move though). Understand you want to wire the VFD directly to the motor (no disconnect or on/off between them). Any on/off will be handled by either the push pad on the VFD or like I said a switch wired to the aux inputs on the VFD. When you have a better idea exactly how you want to control the motor and if this motor will fit and which VFD you are going to get the more specific we can be in wiring it up.

[Salem Ganzhorn]

I have the same DP with a 3/4 HP 3phase using a Teco fm50 VFD. It works very well. I agree mostly with Van: fix the drive train first! If you have lived with a single speed this long maybe it isnt worth fixing the reeves drive. But I would at least look at OWWM before giving up.
Salem

[Richard Wolf]

God, I want to know how people keep their shops so clean?

[Van Huskey]

God, I want to know how people keep their shops so clean?

I don't have a problem keeping a shop clean, my problem is with the house.

[Geoff Crimmins]

A also think the 145T motor will fit. I expect you'll find it has a 7/8" diameter shaft, while the 56 frame motor probably has a 5/8" shaft. (I believe Powermatic made sheaves to fit both shaft sizes.) Redmond Machinery probably has used sheaves if you want to repair the Reeves drive. If you want to use the VFD then that won't be necessary. A VFD is fairly simple to wire, but it take a while to wade through the instruction manual to program it. BTW, you are correct that you have an excellent drillpress that is well worth repairing.

[Mike Heidrick]

I think I would choose a Sensorless Vector constant torque model for a drill press. Here is the JNEV-203-H1 from Teco at $215 http://dealerselectric.com/item.asp?...ID=165&PID=370

Hitachi also makes a nice one.

Also think about the enclosure you will mount it in. There are Nema 4 enclosures for these or you can buy it with one right from the start - many have speed control POTS, direction, and disconnect switchs built right in. Plus you do know it will be a 220V tool after this 3hp and VFD upgrade (maybe it was before?).

[Jerry Hillenburg]

Wow, so much to digest.

Mike the DP is wired 220v single phase now. I plan to keep it 220 single phase but my shop does have three phase.

Mike, you suggest the Vector J NEV-203-H1 from Teco for $215 - it has only single phase input. Van, you suggested the Vector FM50-203-C from Teco for $184 - it has single or three phase input. It would be nice to have both single and three phase input since I have three phase. Aside from the phase input, what is different in these two? Is there another model that combines the advantages of both?

Mike you also mentioned an enclosure for the drive. Are the plastic encasements they come in insuffeciant to protect them? If you put them in a Nema 4 (dust/water tight) enclosure how do you use the control panel?

Geof, no doubt about it, the 1150 is a DP to be proud of and I am going to make mine better with VFD. The motor is a ⅞" shaft. Will try to get OEM step-cone sheaves from Redmond Machinery. If they are crazy expensive I will talk to Grainger or McMaster Carr.

Salem, As of today, I am now a member of OWWM (http://www.owwm.org/viewforum.php?f=1). I plan to spend some time there.

[Van Huskey]

I think I would choose a Sensorless Vector constant torque model for a drill press. Here is the JNEV-203-H1 from Teco at $215 http://dealerselectric.com/item.asp?...ID=165&PID=370

Hitachi also makes a nice one.

Also think about the enclosure you will mount it in. There are Nema 4 enclosures for these or you can buy it with one right from the start - many have speed control POTS, direction, and disconnect switchs built right in. Plus you do know it will be a 220V tool after this 3hp and VFD upgrade (maybe it was before?).

Mike correct my logic but I don't see the need for a sensorless vector drive in his application. The FM50 will give constant toque down to 6hz. The vector drive will adjust the output via motor feedback to keep the RPM constant under load but I don't see how that is needed here. He is using a motor with 4 times the HP of the original (I think it was 3/4hp) and more than the single blet drive train will carry anyway. The motor will slow from synchronus speed (1800) to plate speed (1725) at 3hp so it is unlikely that after gearing the bit would slow more than 20-30 rpm at 3hp and in practice 10-15 rpm at the point the belts would slip, I just don't see that loss of speed at SERIOUS HP requirements being an issue here. That all said if he wants a speed pot right on the drive instead of using the up/down buttons or installing a remote pot then that would be a good low cost drive for that feature.

As for the enclosure a NEMA 4 would cost more than the drive itself, plenty of people just mount them with their "whimpy" IP20 rated chassis right to the press.

[Van Huskey]

Wow, so much to digest.

Mike the DP is wired 220v single phase now. I plan to keep it 220 single phase but my shop does have three phase.

Mike, you suggest the Vector J NEV-203-H1 from Teco for $215 - it has only single phase input. Van, you suggested the Vector FM50-203-C from Teco for $184 - it has single or three phase input. It would be nice to have both single and three phase input since I have three phase. Aside from the phase input, what is different in these two? Is there another model that combines the advantages of both?

Mike you also mentioned an enclosure for the drive. Are the plastic encasements they come in insuffeciant to protect them? If you put them in a Nema 4 (dust/water tight) enclosure how do you use the control panel?

Geof, no doubt about it, the 1150 is a DP to be proud of and I am going to make mine better with VFD. The motor is a ⅞" shaft. Will tryo try to get OEM step-cone sheaves from Redmond Machinery. If they are crazy expensive I will talk to Grainger or McMaster Carr.

Salem, As of today, I am now a member of OWWM ( http://vintagemachinery.org/ ). I plan to spend some time there.

Teco makes the same drive with 3 ph input, there are plenty of 3ph & 1ph input Vector drives but as I said I do not think you need it, but if you decide to get a vector drive instead of just a V/Hz drive like the FM50 know there are PLENTY of choices, but I am not sure if any are as cheap as the Teco Mike linked to.

They make NEMA 4 enclosures to fit most all these drives with full use of the front controls but they are EXPENSIVE the 3hp Teco I mention is ~185 with its native IP20 protection and near $500 with a NEMA 4x enclosure. Some people put them in large metal boxes (need about 4 times the cubic area of the drive itself for cooling) and run all the controls remotely, in this case all you need is on/off and VS, those can be run with small gauge wire like 18g thermostat wire. Again most of the DP setups I have seen use nothing more than the IP20 case they come in, your shop looks like it has good dust collection...

If you want to get in touch with a large group of VFD gurus go to Practical Machinist, they have an entire forum devoted to phase conversion and VFDs. You will get a lot of varied opinions though.

This looks duanting and you can spend all your extra time for 2 lifetimes learning about VFDs and motor control BUT you will see very quickly that all you NEED to know to do this conversion will come very quickly and painlessly. The drivetrain conversion will probably take more work and thought. My first thing would be to compare the cost of fixing the Reeves drive vs going VFD.

[Mike Heidrick]

Its not that the chasis is whimpy, its is protecting the drive from dust. No IP20 drive should ever be mounted outside an enclosure in a dusty environment. Folks do it all the time yes, but that does not make it right. An enclosure that has 2" of space around the drive is sufficient.

All controls can be remote mounted.

The loss of hp at low speeds would be the concern and why I recommended . Plenty of stories on PM and even Alan on woodnet has had issues at slow speeds with his setup. Again feel free to do what you need to. Just know the speed ratings you need to keep the available hp.

www dot forums.woodnet.net/ubbthreads/showflat.php?Cat=&Board=UBB2&Number=5797783&page=2 0&view=collapsed&sb=1&o=&fpart=1

If you have 440V 3 phase then search (#1708) Bonfiglioli Vectron VFD 3Phase 3HP 6.5am 2.2kw SYN10 T 400 09 AF NEMA4X on ebay. I use one of these on my bandsaw feeder (mine is 1/2hp though). They are awesome. $270. Awesome deal for ip65 nema4 enclosure.

[Van Huskey]

Mike, I certainly wasn't saying I was right just what my thoughts would be.

I didn't mean the standard IP20 chassis was pyhsically weak just weak on protection, basically open air with regard to dust, maybe worse than that since it has active cooling. My thoughts were based on almost every VFD I have seen in a woodshop was sans enclosure and I haven't seen anyone attribute a failure to environmental conditions but it certainly could happen.

Regarding the torque/hp. Correct me if I am wrong! The FM50 is rated for contant torque to 6hz so constant torque down to 175-180 rpm at the motor depending on load. The problem isn't torque it is HP as HP will drop in a linear fashion with RPM so at 175 rpm the motor will only produce .3 HP. Lets say we want to keep HP at or above the stock 3/4hp since Jerry never said he needed more HP than he had. As long as we keep the rpm of the 3hp motor at 432rpm or above it will produce the same HP as his stock motor (or more). So we need to never go below 15hz to keep the 3/4hp. The vector drive (and all cheaper vector ones) use an internal sensor to monitor the load and adjust the output to keep rpm constant (very important in some applications) and would help keep the motor from bogging in a DP application if the drilling becomes too hard. However, Jerry is planning to put on a 3hp motor with 4 times the HP of his stock motor. This motor will drop to 1725rpm at 3hp (not factoring in the 1.15 service factor). Moving into a practical example lets say Jerry is using a mechanical 4-1 reduction at 60hz the motor will be running 1725rpm (or a little more with less than full load) and the spindle will be at 432. (Low speed stock on the 1150 is 400rpm) At 432rpm he would have 3hp (but the single belt won't transfer that anyway). Now, drop the frequency to 15hz and your spindle is at 107rpm and you are getting 3/4hp if Jerry trys to stop his spindle like Alan with his hand he will get wrapped around the DP! Jerry will have a 4-1 electronic range without dipping below his normal HP, if he sets up his low speed at say 250 rpm he could run from 250 to 1000 rpm without touching the belt and never have less than 3/4hp (and never go over 60hz, so he could even extend the range). My point being Alan and the other people that have low HP at low speed didn't get a motor with 4 times the stock HP, that fixes a LOT of the potential issues. Many people buy a 3ph DP and just add a VFD then they end up with miniscule amounts of HP at low speed, even a vector drive isn't going to do much for the large difference.

Again I could be completly off base (wouldn't be the first time) but Jerrys massive motor (by DP standards) gives him all kinds of breathing room.


The most vulnerable part of my proposition is how much torque is actually needed for the bits at slow speed, in my example the mechnical reduction increases the torque by a factor of 4, is this enough??? Then again with just two step cone pulleys instead of the normal three in a non-VS DP what is the maximum mechanical reduction, it may be closer to 3-1, then all the numbers need to be run again. Much easier when you have a standard 12-16 speed drill since you are probably going to be able to get up to 10-1 mechanical advantage.

[Rick Fisher]

A 3hp Motor on a Drill press won't cause any problems due to the configuration of the sheaves and pulley's .. The middle speed will have the most power.. on the fastest and slowest speed, there will be little change in power compared to a stock motor ..

The maximum power that motor can transfer will be limited to the size of the smallest sheave.

A 2.65" Sheave will transfer 1.7 hp in a 2 spindle application ..

The thing is .. the Drill press was designed to work well with a smaller motor and the sheaves will transfer all the power the Drill press needs.. The rest is just electron's and maybe belt wear.. lol

My point is .. if your going to skip the stock pulley system to change speeds, leave it on the middle section, avoiding the smallest sheaves... You will get a bit more power ..

If you put a fancier VFD on the press and run it on the slowest or fastest speed, say the smallest sheave is 1.35" .. your motor losing 66% of its power would still have more power than needed.

[Mike Heidrick]

It sure sounds good and worth a try IMO.

[John Coloccia]

re: VFDs

If you're going to go this route, I suggest getting one with a knob.

I do wonder, though, why not just fix the Reeves drive?