Tos Grinder/Planer

Greetings All,
I am in the market for a large table/long stroke
bed type mill and came across a 2mtr stroke planer
grinder with all slideways in excellent condition.
The machine is overall 11.4 tons with massive dc
varible speed drives which draw 100 amps....too
much for us without going for a transformer.

As this is a +-1978 model, is it not possible to dump the old electics for something more modern?
that would use less power and still be efficient.
We want it to flatten plate liners etc and as it has a grinding head that seems to take a large cup wheel and a horiz/vert heads, seems to be a usefull machine. cost = usd 13,000.

The manual shows very little of the mechanicals,
that are pretty much self explanetory, but the electricals take up a A4 3/4" thick manual showing
wiring and trouble shooting....all in german.

It seems Tos went to great detail to create an
electrical system that works but seemed to accept
the fact that electrical problems would be encountered on a regular basis.

Are planers as outdated as shapers with the modern
milling inserts and feeds? Are there inserts and tooling out there designed to take the impact one
would get with planing?.

A thought came to mind of making a milling head and putting a long leadscrew on the table so one could feed the table to exact co-ords.

Like I said, the machine is in excellent condition
with no scratches on any slides or the bed and I
have a 2m stroke with no table sag or rock. I
want to hold a 0.02mm over the length of the stroke and the 750mm wide table, and from what I see, it may be possible with the right setup.

Any idea's or have you seen any mods to a machine like this?

Thanks
Andy

A converted planer makes one of the most versatile, user-friendly machine tools. We have a planer mill at one of our facilities. It started out by being built in 1939 as an openside planer by Cincinnati-Hypro, for the US Naval Shipyard at Norfolk, Va. They sold it in 1947 to s machine shop in Philadelphia, PA, who ran it as a planer until 1972. It had the massive DC drivemotor for the platen you describe and DC motors for rapid traverse of the various feeds. In 1972, the shop in Philly converted this planer to a planer mil with the addition of two 30 HP milling heads. Suddnely, the massive DC driv eon the platen made no sense and gave no real good control for feeding/stopping as was needed for milling. They cobbed up a lighter DC drive of about 10 HP and later added DRO. We bought the planer mill off their shop floor and had it rebuilt before putting it into use in our facility. The rebuilders had done this sort of thing a number of times, and simply got rid of all the existing DC drives on the rapid traverses, got rid of the cobbed-up DC feed driv eon the platen. The went over to AC Vector Drives (Baldor), and upgrade the DRO asdie from rescraping all the sliding surfaces. Other thing they did was to add an independent lube oil pump and spin-on type filter since the original lube oil pump (for bedway lube) worked off the pinion shaft on the platen feed. We would be making smaller moves at slower feeds, so having an independent lube oil pump worked really well for us. The Vector drives are programmable, and allow us to creep the platen or the crossfeed or downfeed or rapid traverse them. We are doing really fine work with this machine tool. We added a right angle head on our vertical milling spindle and are really handling some interesting jobs.

As an aside, the firm which furnished us a rebuilt/upgraded LeBlond Engine lathe has a big bedway grinder in their shop. It is a converted G.A. Gray planer with a way grinding head. I think they may have gotten rid of the original DC drive used when the machine was a planer and went to some sort of smaller drive with more control.

For the amount of trouble you may encounter trying to put the TOS electrics right, if you are intending to use the planer as a grinder or mill, you might want to consider replacement with one of the new AC Programmable drives. The DC motor drive on a planer is generally larger than what is needed for milling or grinding, and the controls usually take the form of a cabinet full of clapper-type relays and similar. The old electrics on planer DC drives are usually maintainence-intensive, so replacement with an AC Vector drive is something to consider. On our planer mill, we use the vector drive in conjunction with DRO and are able to creep the table right to the thousandth if we need to feed to a precise location. We did not originally envision needing that degree of control as we planned to be taking only long cuts. However, as we got into the work and got to know the machine, we found we could creep right up to where we needed to be. We have a pendant type controller, so it works out handily. The Vector drives eliminated a mess of old-time electrics with rehostats, calpper type relays, contacts and attendant problems. The Vector drives also use a fraction of the power the old DC drive used, so something to consider. Any good electric motor shop should be able to retrofit the right type of AC drive. Baldor makes a wide range as we have used them on other machine tool retrofits as well.

Joe Michaels

Joe Michaels

We have a 48x48x192 Gray planer at work, which has a dc drive. This machine is a standard planer with no milling heads. As Joe mentioned the dc electrics are a real hassle. There are two big cabinets full of every type of relay, resistor, rheostat, and contactor you can imagine. Originally the dc came from a 75hp motor-generator set that was supplied with the machine. This in turn powered the 40hp dc motor, which is directly coupled to the drive pinion. The speed is varied by changing the field voltage in both the generator and the motor.

About a year ago the motor generator had a short to ground at the generator commutator. Talk about an explosion! Melted copper ran from the unit. The local motor shops qouted rebuilding it for $10-12,000. So I thought what a great time to convert to an ac vector drive.

After looking into the feasability of this we decided to buy a used generator and motor. We could not use the old motor, as the MG set had one common shaft for the motor and generator. The reason we went back to dc is that due to the low speed of the drive pinion an ac motor would have to be approx. 100hp to get the same torque. We thought of a gearbox in line with a smaller ac motor, but again your talking big bucks. I think the whole set up would have cost around $30,000, plus whatever it would cost to add the reversing controls, wiring, etc.

We ended up buying a used 100hp ac motor and a big old dc generator from a dealer in such things, thier name escapes me. A few pieces of channel and a coupling and we thought we were ready to go. We fired everything up and had no power for some reason. Come to find out the generator was not self exciting as advertised. We looked into a solid state dc drive to power the field for the generator. It was something like $2000. So I bought another self exciting generator, much smaller, to make the field for the big guy. A motor off the old air compressor in the storage shed drove it nicely. It is somewhat humourous to see the little MG set bolted to the floor next to the big one. At the time we were wondering if we'd have to get an even smaller set to make the field for that one. It turns out that it worked fine. With the help of one of the most knowledgable men in the old school dc drive worlds help (Milton from PB electric), we got the old girl up and running again. Keep in mind this is just for planer mode only.

I have often thought of putting a milling head on this machine. I hesitate to convert to a planer mill only setup, because we use every bit of versatility that only a planer can offer. I did once see a set up at another local shop, where they had thier planer rigged for both milling and conventional planing. They had a small ac drive through a gearbox and a chain that drove a sprocket on the pinion shaft. When used as a conventional planer the chain was simply removed. They took one of the standard rail-heads off and replaced it with a Cadillac 50hp milling head.

The other thing that few people realize is that a planer with conventional planer tooling can make a part a lot flatter than a planer-mill can. This is due to the fact that with a single point tool there is less part deflection, heat, etc. Our planer can hold 0.001 over its entire table. I always thought that I would use a milling head for roughing, and then finish with a single point tool in planer mode, the best of both worlds. But when we have a lot of roughing to do, we run both the rail-heads at once, with one tool set about 1/2 inch below the first one. So effectively your removing 1" per pass with about a 1/8 feed per stroke. Granted you could mill this off with a carbide face mill faster, the tooling is cheap, and we just let her cut like this all day, unattended. We use HSS tooling mostly, but some carbides for finishing iron and bronze. Plus it is fun to have a chip that is wound like BX cable 2" in diameter, and 6 feet long that you can pick up from one end without it breaking.

And, although I have never run one, I have always shyed away from TOS machines. I looked at several horizontal boring mills, and found them to be of poor design and construction. But again, that is just my first impression.