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Gorton 1-22 Mastermil Tracemaster mill -- the fly in the honey

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
Howdy folks,

Some time ago I acquired a 1962 1-22 Tracemaster mill with a B360 3D True-Trace unit, in unknown working condition.

According to the successor corporation that owns the rights to True-Trace, the tracer valve is totally obsolete and no parts are available.

Based on a read of some old historic brochures, when Gorton came out with their Mastermil line, now fitted with the True-Trace units, they pitched the "Tracemasters" as being "fully functional manual mills". No doubt this approach was intended to appeal to and placate the "old school" shop owners who weren't so sure about stepping up to "new technology" and wanted to keep one foot in what they knew and understood.

I took solace in this "fact" because I always had doubts about whether the tracer unit would work. Hence, it was comforting to know that I could use the machine as a manual mill if it did not.

Because the machine was so grungy, and because my attention is so divided with so many other grungy acquisitions, I never fiddled with the knobs and levers until I could get around to thoroughly cleaning and servicing the machine. Only yesterday, we finally got around to it. For no particular reason, I started with the Y axis, cleaning the ways on both sides of the saddle with mineral spirits, then applying fresh oil, and moving the saddle back and forth until it was clean and lubed. Then I cleaned and lubed the vertical ways and got the knee clean and operating smoothly through its full range of travel. Both the saddle and the knee have conventional acme lead screws to mechanically control their full range of travel. The knee is also controllable by a hydraulic cylinder.

Finally, I turned my attention to the table. The left end of the table is fitted with a long hydraulic cylinder. The table does have a hand wheel at the right end but has no visible lead screw. The actuator shaft is smooth (ball screws???). After cleaning and lubricating the table, and greasing the hand wheel, I discovered that, stop to stop, the table's total mechanical range via the hand wheel, is only about FIVE INCHES!

It happens that this machine was custom built in 1962 for the Marshall Manned Space Flight Center, the predecessor to NASA. Hence, I've now been b**** slapped by the possibility that it indeed was NOT built as a "fully functional manual mill".

If this turns out to be the case the burning question becomes:

Where to now???

My dilemma with the tracer unit is that it may or may not work. The problem is that facing spending hundreds of dollars in new hoses and fresh fluid just to test the system. Even if it works, there are no guarantees from one day to the next. So, it's possible, perhaps even likely, that, only after I spend a significant amount of money, the tracer won't work at all, or will work for only a short time before giving up the ghost.

I may be a crazy fool, but that doesn't mean I'm stupid... so, I may indeed take the plunge. Nevertheless, before I do, metinks it is prudent for me to explore the full range of options.

Although I'm no expert, to my eye, this mill is in very good shape, all things considered. Also, I'm a simpleton. And this mill is.. er.. simple. The table itself, is quite large and wide. It has a fixed head that neither swivels nor tilts. The motion is controlled by a long hydraulic cylinder that sticks out the back of the ram. So, with an operational tracer and/or viable alternative means of mechanical and/or hydraulic control, the work envelope is quite spacious.

Save for those add-ons, the mill is totally manual. It doesn't have the "dyna drive", power down feed, or any of those other accessories that are so often on these mills and that, today, don't work, due to the obsolete vacuum tube electronics. Save for the hydraulics, the mill is fully functional and seems to be tight and well cared for.

In summary:
On the Y axis
the table's range of mechanical movement is quite spacious. This could be increased dramatically by the ram, which is only hydraulically controlled as best I can tell.

On the Z axis
there is full mechanical control of the knee with a conventional crank. The knee is also controllable by a hydraulic cylinder.
The spindle has a down feed is fully mechanical and fully manual. There is a lever (like a drill press) or a micrometer stop controlled hand wheel. Otherwise, the machine has no power down feed, no table power feed, and no knee power feed.

Hence, on Y and Z, I'm golden.

But on X, unless I'm overlooking something obvious, from stop to stop, I am limited to a puny 5 inches of travel, more or less.

A friend, and member here, (you know who you are...) has suggested that fitting a 48" Bridgeport lead screw and half nut might be an option. It appears that a brand new lead screw can be had on ebay for under $400. Under that scenario, I would endeavor to retrofit a lead screw and install a DRO, and scrap the hydraulics. As a practical matter this is appealing. However, the machine DOES have some historic value in my mind. And by that, I'm not thinking "I can sell it for a bunch of money". Rather, I say it from the stand point of "responsible conservatorship". I only care about money when I'm totally out of it.

So, under that mind set, I'm wondering about the viability of finding parts from another appropriate Gorton mill, and re-fitting it with such components as may be required to make it a "fully functional manual mill".

The ideal solution from my standpoint would be an approach that would not permanently alter the mill, in case the Smithsonian comes knocking at my door after I'm dead and gone. I've thought about how I might install a DRO and even power the cylinder with a hydraulic hand pump such as a porta-power unit, or some similar off the wall fix that will overcome the problem cheaply, and without permanently altering the machine.

If y'all have any suggestions as to a viable retrofit I will be happy to hear them. I have not given up on the idea of getting the hydraulics going. However, I'm actually considering buying a hydraulic hose crimper and doing it myself rather than plunking down the kind of money it would cost to replace all the lines on the mill.

But any and all ideas, observations, and comments will be welcome - especially those by somebody who's "been there and done that".

Sincerely,

Vernon
 

Heavey Metal

Banned
Joined
May 10, 2011
Location
Texas
Put a crossover in the x cylinder with a needle valve.

Now can you push x to within 5" of where you want to be.

Look there may already be a valve plumed in
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
Heavy,

I think I understand the concept... and I like it!

Not sure what a cross-over valve looks like... mebbe I will take some detail pictures and post 'em. Otherwise, I will try google images.

Thanks!

V
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
Bill,

Very left brain. Thanks. Repair work is indeed where we want to be. As best I can tell, that's the only dimension to the evolving trade that allows for creative thinking and problem solving.

Since I don't have a left brain I am unlikely to do any kind of real analysis. However, that is not to say that I'm blithely gonna start a bonfire using franklins for tinder.

V
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
In furtherance of the suggestion Heavey Metal makes above, it appears that Harbor Freight has a ten k foot operated hydraulic pump for just north of a franklin. My original thought was a hand operated pump but foot operated would be far better. There is indeed some kind of valve with a hand wheel plumbed into the x axis cylinder and i had wondered what it was for.

I will shoot a couple of pictures later in hopes yall can orient me as i k.ow next to nothing about hydraulics. But if a cheap foot pump will reliabl move the table back and forth that should get me where i need to be.

v
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
I don''t really know what a needle valve looks like or does... but here are a couple of pictures. One is the cylinder mounted on the left end of the Gorton mill table. The other is a picture of two valves that appear to open and close two lines. I presume that one valve and line controls movement in one direction and the other controls the opposite direction.

If it is a viable plan to plumb in a foot pump that would be great.

Thanks again!

V
 

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Galane

Hot Rolled
Joined
Dec 6, 2010
Location
Idaho, USA
I just had a look at one of these today. A possible upgrade short of replacing the hydraulic cylinders with ball screws and servos or steppers is a fixed volume hydraulic system where each axis has its own rotary vane (or other constant volume type) pump and a servo or stepper to drive it.

As long as the hoses can't expand and the fluid is incompressible and the pumps always move the same amount of fluid per degree of rotation, there's a constant relationship between how much the pump turns and how far the cylinders move. Put encoders on the motors and run it just like having the motors driving ballscrews. Still have the cylinders sticking way out the back and to the left, but wouldn't need that huge fluid tank, no reservoir at all, just the fluid in the pumps, lines and cylinders.

With hand cranks on the motors it could even be used manually.

If the manual version nut block and screw for the X axis can be swapped for the ram, then you have an easier path to retrofitting ballscrews for normal CNC drive. Put a simple reversible hydraulic pump on the ram to manually move it fore and aft then put together one constant volume hydraulic loop for the knee for Z axis.

It's a big, beefy machine, unfortunately stuck with a terribly obsolete control system. I was looking up on old Bridgeport mills last night with this same system and they could cut at the extreme speed of up to 13 inches per minute. Paint dries faster than that. ;)
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
I just had a look at one of these today. A possible upgrade short of replacing the hydraulic cylinders with ball screws and servos or steppers is a fixed volume hydraulic system where each axis has its own rotary vane (or other constant volume type) pump and a servo or stepper to drive it.

As long as the hoses can't expand and the fluid is incompressible and the pumps always move the same amount of fluid per degree of rotation, there's a constant relationship between how much the pump turns and how far the cylinders move. Put encoders on the motors and run it just like having the motors driving ballscrews. Still have the cylinders sticking way out the back and to the left, but wouldn't need that huge fluid tank, no reservoir at all, just the fluid in the pumps, lines and cylinders.

If the manual version nut block and screw for the X axis can be swapped for the ram, then you have an easier path to retrofitting ballscrews for normal CNC drive. Put a simple reversible hydraulic pump on the ram to manually move it fore and aft then put together one constant volume hydraulic loop for the knee for Z axis.

It's a big, beefy machine, unfortunately stuck with a terribly obsolete control system. I was looking up on old Bridgeport mills last night with this same system and they could cut at the extreme speed of up to 13 inches per minute. Paint dries faster than that. ;)

Galane,

Not sure I understand it but I like it! One of our sons will be starting at Texas A&M in their school of mechanical engineering in about two weeks. Maybe he will take the idea and run widdit!

Best holiday wishes.

VT
 

tdmidget

Diamond
Joined
Aug 13, 2005
Location
Tucson AZ
I just had a look at one of these today. A possible upgrade short of replacing the hydraulic cylinders with ball screws and servos or steppers is a fixed volume hydraulic system where each axis has its own rotary vane (or other constant volume type) pump and a servo or stepper to drive it.

As long as the hoses can't expand and the fluid is incompressible and the pumps always move the same amount of fluid per degree of rotation, there's a constant relationship between how much the pump turns and how far the cylinders move. Put encoders on the motors and run it just like having the motors driving ballscrews. Still have the cylinders sticking way out the back and to the left, but wouldn't need that huge fluid tank, no reservoir at all, just the fluid in the pumps, lines and cylinders.

With hand cranks on the motors it could even be used manually.

If the manual version nut block and screw for the X axis can be swapped for the ram, then you have an easier path to retrofitting ballscrews for normal CNC drive. Put a simple reversible hydraulic pump on the ram to manually move it fore and aft then put together one constant volume hydraulic loop for the knee for Z axis.

It's a big, beefy machine, unfortunately stuck with a terribly obsolete control system. I was looking up on old Bridgeport mills last night with this same system and they could cut at the extreme speed of up to 13 inches per minute. Paint dries faster than that. ;)
No. No. No.
No you can't pump from one end of the cylinder to the other.
No. you can't run without a reservoir
No you can't run with a foot pump
No you can't turn the pump by hand
Yes the pix posted are useless, can't even tell where that is on the machine.

Post pix of the whole machine and some that show the relationship of one part to another
need one of the control valve
 

Galane

Hot Rolled
Joined
Dec 6, 2010
Location
Idaho, USA
Why wouldn't a fixed displacement pump in a constant volume hydraulic system work to drive a cylinder both directions by reversing the pump to change directions?
 

tdmidget

Diamond
Joined
Aug 13, 2005
Location
Tucson AZ
Why wouldn't a fixed displacement pump in a constant volume hydraulic system work to drive a cylinder both directions by reversing the pump to change directions?
Because the displacement of the rod end is less than the tube end. What that would do is effectively lock the cylinder. The reservoir is a place for the excess to go to or to pull additional oil to go the other way.
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
At this point the preferred plan is to see if we can fab up an inexpensive lead screw and half nut (or whatever it's called) and install a DRO. An alternative plan would be to install some kind of makeshift hydraulic system such as Galane is suggesting - also with a DRO. We would be happy to have the thing be operable as a manual mill - preferably with power feeds on all axes and a DRO. It is a very nice mill although it will never be as versatile as a Bridgeport.

V
 

tdmidget

Diamond
Joined
Aug 13, 2005
Location
Tucson AZ
Why not get a manual for this thing and see what the OE did? If they said that it could be run either way then maybe you just have some parts missing. If you only have 5.5 inches stroke out of that cylinder then something must be wrong right there.
 

Doozer

Titanium
Joined
Jul 23, 2001
Location
Buffalo NY
What you need is an
Orbital Steering Valve.
I think Surplus Center has them.
They are used in full hydraulic steering systems
like tractors or off road stuff, that only use a
hydraulic cylinder to steer. No mechanical linkage
to the steering wheel, all hydraulic steering.
Would work well on a Moog hydropoint as well.

--Doozer
 

Vernon Tuck

Stainless
Joined
Oct 26, 2008
Location
Brenham, Texas
Why not get a manual for this thing and see what the OE did? If they said that it could be run either way then maybe you just have some parts missing. If you only have 5.5 inches stroke out of that cylinder then something must be wrong right there.

TD,

Here's some history that I hope will clear things up. This mill was built in 1962. It is a Gorton "Mastermil" model 1-22 "Tracemaster". It was custom built for the Marshall Manned Space Flight Center - the predecessor to NASA. No doubt it was ordered by the US gummint in their haste to catch up with the Rooskies after they launched "Sputnik" in 1959.

To be clear, Gorton, which no longer exists, was, back then, a major player in the machine tool game. There machines were beautifully and massively made. And they featured "cutting edge" technology. Of course that was then. Today, they are obsolete.

Gorton manufactured a manual machine called the 1-22 "Mastermil". They also manufactured a 1-22 "Mastermil" "Tracemaster". The "off the shelf" Tracemaster was marketed as being "fully functional as a manual mill". No doubt they marketed them this way to appeal to the grumpy old shop owners who were reluctant to embrace this "new fangled tracer technology".

However, THIS machine was custom built to the specifications of the space mission honchos. I did not know any of this when I bought it. I HAD read up on them and indeed HOPED that it would turn out to be a "fully functional manual mill" because I was well aware that the tracer equipment may or may not be operable.

Once I got the thing into our shop it took about a year to get it hooked up as I was busy with some other acquisitions plus some remodeling - especially electrical work. Today, the MILL ITSELF it operable with a VFD. To date, I have NOT brought the tracer hydraulics online.

So, to clarify, the X axis 5 inch travel limitation has nothing to do with the hydraulics. Rather, the mill has 5 inches (give or take) of mechanical lead-screw travel on the X axis.

I don't know why this is, but I speculate that the purpose was to "zero" the milling head when commencing tracer machining. No doubt there are some people in this forum (John Oder where are you??) who have experience with - or at least memories of - tracer mills.

You will please keep in mind that I am not a machinist. Hence, I barely understand how a manual mill works or should work. My knowledge of tracers is based on what I've read. My experience is a virtual goose egg.

The reading I mention above has consisted of every at least a cursory review of every manual I've been able to find for every permutation of the 1-22 mastermil (both fully manual AND tracers). I've also carefully studied many photos of different machines I've found on ebay and elsewhere.

My conclusion is that this machine is significantly different from the manual machines AND the standard issue tracemasters. Among other differences, our mill is significantly more bare boned and simple. For example:

The manual 1-22 mills generally had a power spindle down-feed, a power knee, and power table feeds. All of those "cutting edge" features were however, vacuum tube based. It would appear that the people who own these machines today are pulling their hair out trying to figure out work-arounds for these systems which are today totally broken and totally obsolete.

I will get some pictures of the entire mill and post them soon. But meanwhile, here's what is, in my mind, significant about this mill: It has a hydraulic cylinder mounted to the left end of the mill (facing it) as well as a hydraulic cylinder mounted behind the ram. The tracer arm is mounted to the right side. If the hydraulics were operational the mill would have a huge work envelope! The table is quite ample. It's 12"x54" if my memory serves me.

As I've already mentioned if the table is centered (it is) the hand wheel mounted to the right end of the table will move the table approximately 2-1/2" to the left and the same amount to the right of center.

The milling head neither swivels nor nods. As best I can tell, the ram does not have the ability to move by any means except hydraulic.

The quill however can move down (just guessing here) about 8 - 10" with an optional lever (sort of like a drill press) or alternatively, with a micrometer adjustable downfeed.

The knee, which is movable with a hand crank, has a significant range of motion. Don't know the range of motion but it's ample. The knee's "lead screw" if that's what it's called is INSIDE OF A HYDRAULIC CYLINDER. Hence the knee moves up and down two ways.

In the Y axis the table's motion is controllable only mechanically. The range of this mechanical motion is quite ample and measurable by a micrometer adjustable hand wheel. This significant range of Y axis motion is hugely increased by the ram hydraulic cylinder - or at least would be, if the tracer hydraulics were operational.

So, in summary, the signifcant limitation on the mill (the fly) is this limited table motion on the X axis. But the work envelope (the honey) is potentially larger than any mill I've ever seen or heard about, although, given my background, what the hell do I know??

But I do know beautiful machinery when I see it and this is a beautiful machine if ever I saw one.

It is not lightly that I consider stripping off the tracer hydraulics. The only reason I'm reluctant to attempt to get the tracer going is that it's potentially such a money pit. There are about 100 miles of hydraulic hoses between the mill and the hydraulic power unit. These hoses don't look too bad but if they blow (and they will sooner or later) it will be a big mess and a potential health and safety hazard. Replacing them all will cost a significant hunk of dough as will replacing the approximately 40 gallons of hydraulic fluid in the power unit. Once I've spent that money there is an excellent possibility the tracer valve will not work at all or will not work properly. And if it does, for how long?

But to be clear, the machine is complete. And to my eye, save for the toll taken by the passage of 50 years, it is complete. And it is not too far from what I would call "pristine".

In its current condition and with it's current limitations the machine would probably be adequate - and possibly superb - for pistol smithing and small engine work. So, in line with the philosophy of "when life gives you lemons make lemonade" maybe we will be happy with what we've got. It's not like I don't have another mill. There's a Bridegeport 2J in the back room. But compared to this Gorton the Bridgeport looks like a happy meal toy.

As soon as I can find time, I hope to dismount the table cylinder and the table and get a look at the lead screw. I'm hoping I can cobble something together that will enable me to operate the mill manually, hopefully with Bridgeport style power feeds on X and Y in conjunction with a DRO, and moth-ball the hydraulic cylinders for posterity. In other words, I hope to re-task the mill without permanently altering it. This thing very well could have made parts that went to the moon.

Regards to all. Please keep those "off the wall" "out of the box" and "out of this world" ideas coming.

VT
 

Galane

Hot Rolled
Joined
Dec 6, 2010
Location
Idaho, USA
How about using a cylinder to push a cylinder? Match cylinders of the same volume, but not necessarily the same diameter and stroke, to the table, ram and knee cylinders.

If you can't get the volumes to match connecting a pair of cylinders' ends together with hoses, use two single acting cylinders, one to push each way on the cylinders on the mill. That would take 6 cylinders and motors to drive them instead of 3 and most likely some tricky calculations by the control software to keep things balanced and knowing where the table and head are, but it would do away with the big oil tank and valves and most of the hoses.

It's easier to push a certain volume of oil with a smaller diameter, longer stroke cylinder than it is to push the same volume of oil with a larger diameter, shorter stroke cylinder. Like the difference between a regular hydraulic car jack and a NASCAR jack. The garden variety one has a tiny pump cylinder and it takes a lot of handle strokes to lift a car. The NASCAR style has a larger pump cylinder and can lift a car in 3 or 4 pumps, but it takes a big guy to be able to apply the force in the shorter time to do it.

To avoid a linear drive pushing a hydraulic cylinder piston from getting too long, fit an offset block to the end of the ram, with a bearing, and "fold" the leadscrew drive alongside the cylinder.

With the drive cylinders arrayed in a vertical rack, the effect of them going up and down while the mill moves around could be quite entertaining.
 

tdmidget

Diamond
Joined
Aug 13, 2005
Location
Tucson AZ
Galane, are you related to Rube Goldberg? I don't think that the OP needs more complication than it has now. What, by the way, would make these "drive" cylinders go up and down?

Vernon, manuals are available on line. One site has the entire manual on line but not clear enough, at least on my puter, to read.
 

Danny VanVoorn

Titanium
Joined
Nov 3, 2002
Location
St.Louis, Missouri, USA
TD,
The manual 1-22 mills generally had a power spindle down-feed, a power knee, and power table feeds. All of those "cutting edge" features were however, vacuum tube based. It would appear that the people who own these machines today are pulling their hair out trying to figure out work-arounds for these systems which are today totally broken and totally obsolete.
VT
That maybe true for a 1962 model but not for the 1968 1-22 Mastermill I had, it was equipped with an electronic variable speed drive system made by Reliance that worked great and no vacuum tubes.
I have a limited amount of time on a tracer mill, I was given an assignment in trade school to make some tools for the body shop class. Why only the 5" travel seems really odd but could have been special built for use to make batches of very small parts. I am certain that a working and set up properly tracer mill could hold very tight repeatability. The shop I work at currently used to make repair fittings for air frame parts from plaster molds taken directly from the damaged area on a Cincinnati Hydrotel tracer mill. I didn't get directly involved but still find that work impressive.
Dan
 








 
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