Tormach Rigidity

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rexcsmith
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Tormach Rigidity

Post by rexcsmith »

I'm looking at the Tormach 1100. I'm wondering how it does at cutting steel. I've found videos that are impressive when cutting aluminum, but nothing to do with cutting steel. I'm wondering if the machine is rigid enough to use a 3/4" cutter on mild steel? I'm a little disappointed the machine only has a 1 1/2 HP motor.
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Dave_C
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Re: Tormach Rigidity

Post by Dave_C »

Rex,

There are Utube videos from NYCCNC with lots of test using end mills and face cutters just to show what this machine will do. It is pretty impressive to say the least!

I've actually studied the base and column designs of several of this size machine from all the manufacturers that I could find and I'll have to admit, the PCNC 1100 has the most material in their design and that usually means a more rigid machine.

I'm not sure why you need a 3/4" end mill with a CNC machine though because you can do multiple passes at a given depth so easy with CNC programming. I prefer to make lighter passes which generally gives me a better final finish and puts less strain on the machine as well.

Dave C.
I learn something new every day! Problem is I forget two.
RET
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Re: Tormach Rigidity

Post by RET »

Hi,

I wouldn't worry about the spindle motor power. I have a 1 1/2 HP. D.C. variable speed drive on my Bridgeport mill and recently I was using it with a 1" dia. end mill (3/4" shank) to take a 1 3/4" deep cut in aluminum using a roughing cutter at about 150 rpm. That gave a pretty good finish and the chips came off easily without any fuss from the motor (it wasn't even working hard). I was feeding manually and it was easy to tell when the cutter was being forced. As long as you kept below that rate, the feed was easy and was about 4 or 5 inches per minute. I was actually impressed by how much metal you could remove and how easy it was. Of course, the removal rate would be a lot lower in steel, but still respectable.

I wasn't using any coolant. If you used coolant you could double the spindle speed and feed rate and I'm sure that the motor could still handle it.

The difference in performance between a conventional end mill and a roughing cutter is amazing. All you would have to do is take a light climb mill finishing pass with a conventional cutter to get what you want while letting the roughing cutter do most of the work.

CNC doesn't give you any "feel," so you have to know what speeds and feeds are right from your conventional machining experience.

Don't expect production machine performance from any "home" machine because it won't happen. Today's production machine performance is very impressive. The speeds and finishes are "WOW." Remember however, that a lot of their performance depends on the tooling as well as the machine.

Richard Trounce.
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Mid Day Machining
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Re: Tormach Rigidity

Post by Mid Day Machining »

rexcsmith wrote:I'm looking at the Tormach 1100. I'm wondering how it does at cutting steel. I've found videos that are impressive when cutting aluminum, but nothing to do with cutting steel. I'm wondering if the machine is rigid enough to use a 3/4" cutter on mild steel? I'm a little disappointed the machine only has a 1 1/2 HP motor.
I have a PCNC 1100 in my garage, and I'm here to tell you, if you're planning on running a 3/4 inch end mill cutting steel. you are absolutely looking at the WRONG machine.

I run the hell out of mine, but I never use bigger than a 1/2 inch end mill when cutting aluminum, and 3/8 when I cut steel.

I do however cut titanium and inconel 718 on my machine. Truth be told, I'll take all the inconel I can get. I have spent the time and money to learn how to cut it, and it actually cuts quite nicely in a Tormach. It's just very, very slow. But Inconel cuts slow on a Mori or a Mazak too. AND, chips are worth about $2.50 per pound and solids are about $4.00, and when it's customer provided material, that all goes in my pocket.
You can buy good parts, or you can buy cheap parts, but you can't buy good cheap parts.
rexcsmith
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Re: Tormach Rigidity

Post by rexcsmith »

Regarding my question about the 3/4" end mill. It's mainly what I've become accustomed to using with my home brew CNC RF45. It cuts through aluminum like butter. I've been doing mostly aluminum, but now I need to do some steel. The 3/4" end mill shakes the machine in steel. That's why I was wondering what the performance would be in the Tormach. Sounds like if you have a Tormach, you don't go there. I have discovered a couple of good videos of the Tormach 1100 cutting steel with smaller cutters. The approach is much different than I've been using with the big cutter. So, if I go for the Tormach, I'm going to have to change my thinking about how I do CAM setup. No problem there; I'm mainly interested in getting a quality part in a reasonable amount of time.
The other machine I've been considering is the Charter Oak which (I think) is based on the newer RF45. Anyone using that one?
thanks for all the feedback, rex
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Re: Tormach Rigidity

Post by JimGlass »

I heard once a standard Bridgeport, turret, kneemill should not run endmills larger than 1/2". Most of us have run larger endmills than 1/2" in a Bridgeport type mill. There is a big difference between running machine that someone else bought compared to running machines we buy ourselves.

I bought a new JET step pulley Milling machine and a JET 13" geared head lathe in 1999. I never run them hard and so far have never had a "crash". After 16 years of daily use they are still in like new condition with slightly more backlash today that there first day in the shop.

I have seen a couple of Tormach 1100's at the CNC workshop in Ann Arbor Michigan. My gut feeling is a 3/4" endmill will take its toll on that little machine over time. Then again, it is all about depth of cut and feed rates. If you plan to make money with the machine it will be about depth of cut and feed rates.

After 45 years of walking on chips, that is my opinion. Jim
Tool & Die Maker/Electrician, Retired 2007

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Mid Day Machining
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Re: Tormach Rigidity

Post by Mid Day Machining »

JimGlass wrote:I heard once a standard Bridgeport, turret, kneemill should not run endmills larger than 1/2". Most of us have run larger endmills than 1/2" in a Bridgeport type mill. There is a big difference between running machine that someone else bought compared to running machines we buy ourselves.

I bought a new JET step pulley Milling machine and a JET 13" geared head lathe in 1999. I never run them hard and so far have never had a "crash". After 16 years of daily use they are still in like new condition with slightly more backlash today that there first day in the shop.

I have seen a couple of Tormach 1100's at the CNC workshop in Ann Arbor Michigan. My gut feeling is a 3/4" endmill will take its toll on that little machine over time. Then again, it is all about depth of cut and feed rates. If you plan to make money with the machine it will be about depth of cut and feed rates.

After 45 years of walking on chips, that is my opinion. Jim
I would never use a 3/4 inch end mill to cut steel on MY Tormach.

Shortly after I got my machine, I got a 75 piece aluminum job that required some serious pocketing.

After contemplating the best way to do this job, I decided to plunge ruff the pockets. I was able to deliver 5 parts per week and the customer was ecstatic. So was I considering I was getting $575.00 per part. I liked making $2,875.00 per week.
You can buy good parts, or you can buy cheap parts, but you can't buy good cheap parts.
rexcsmith
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Re: Tormach Rigidity

Post by rexcsmith »

After a lot of experimenting, I'm a little more knowledgable about what my RF 45 will do. For sure, no 3/4" cutters on steel. The machine dances the jig with those. It also doesn't care for cutters with inserts. I have a 1/2" 1 flute insert cutter, and it chatters like mad if you try to go down more than about 50 thou. I can do reasonable cuts with a typical 4-flute end mill and the machine behaves itself pretty well. I can run nearly 20ipm taking .1" slices with a .3" deep sidecut. Given that the mill was very well behaved, I think I can push it farther than that on size of slice.
It's pretty clear that the RF45 is not an industrial strength mill. I have to be very careful to keep it from dancing.
That said, I cut out the two Center Plates for the tender on the 10-Wheeler using full 3D CAM. It took a long time, but they came out very nice. Too slow for my taste, so I'm researching a more robust mill to move my home-brew CNC gear onto.
I really like what I see in the Tormach, but I sense that it isn't going to work any faster for me than the RF45 does.
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