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got a chance to run a TM mill. Wow, what a turd

viper

Titanium
Joined
May 18, 2007
Location
nowhereville
We sponsor one of our local universities for race part design, mfg, etc. We decided to take a part in and supervise them running it in their place. We programmed very conservative understanding the TMs have about 5hp or so. I cannot remember the exact cutter engagement but I was really shocked at how much the machines vibrated. We ran a 3/4 2fl dry in Al. Approx engagements were maybe 3/8 axis, 30% radial.

The spindle seemed to be handling the load fine but the vibes were surprising. I really thought the TMs were pretty close to a naked VF but I was wrong. We had a Tree knee mill that was quieter than these.

Now, I realize running more flutes would help as well as possibly using a better cutter all around but this was an educational shop so everything gets broke..... I watched another guy trying to drill press a 1" hole at 1500 rpm in steel with a really long bit.... I had to reach for my ear plugs and when I commented that they needed to slow WAY down, all I got was "we are in a hurry". I think they went through 3 bits for one hole....
 
We sponsor one of our local universities for race part design, mfg, etc. We decided to take a part in and supervise them running it in their place. We programmed very conservative understanding the TMs have about 5hp or so. I cannot remember the exact cutter engagement but I was really shocked at how much the machines vibrated. We ran a 3/4 2fl dry in Al. Approx engagements were maybe 3/8 axis, 30% radial.

The spindle seemed to be handling the load fine but the vibes were surprising. I really thought the TMs were pretty close to a naked VF but I was wrong. We had a Tree knee mill that was quieter that these.

Now, I realize running more flutes would help as well as possibly using a better cutter all around but this was an educational shop so everything gets broke..... I watched another guy dry to drill press a 1" hole at 1500 rpm in steel with a really long bit.... I had to reach for my ear plugs and when I commented that they needed to slow WAY down, all I got was "we are in a hurry". I think they went through 3 bits for one hole....

that bad huh? That isn't good to hear. I was really looking forward to getting one when I graduate... One to start my business.
 
I am sure some people do fine with them but I guess we are used to a little more rigidity. Another thought here is that we are not sure what foundation they are sitting on or if they are leveled correctly which could cause this but we did run 3 different ones and all seemed to do the same thing.
 
I respectfully submit that you did the students a gross disservice by not pointing out the basic shop theory of speeds and feeds. "we're in a hurry" translates to me they they are ignorant of the basic concepts. A calm lecture and explanation and short demonstration will be appreciated by them - it's why they are there!

I worked with college students for nine years and never once let something like that go... they are capable of understanding, by your inaction you implied that that is an acceptable method. Trust me when I say that they will follow but you must lead!

Teach one and that one will teach two and so on...

With best intent,
Bernie
 
I respectfully submit that you did the students a gross disservice by not pointing out the basic shop theory of speeds and feeds. "we're in a hurry" translates to me they they are ignorant of the basic concepts. A calm lecture and explanation and short demonstration will be appreciated by them - it's why they are there!

I worked with college students for nine years and never once let something like that go... they are capable of understanding, by your inaction you implied that that is an acceptable method. Trust me when I say that they will follow but you must lead!

Teach one and that one will teach two and so on...

With best intent,
Bernie

The "drillers" were not part of the group under our supervision. All we could do is make a recommendation and listen to their excuses. There is a reason they have limited access to this machines shop, they ruin tools and machines. As to our running of the TM, we played with feeds/speeds a touch but it was obvious the machine was not going to run out the door but should not be standard practice.

I was actually most pissed about the lack of attention from a few students that just want to be "design" engineers. I had stern words for them and my brother, a senior aero structures design engineer, had a talk with them about how much money it is costing airplane companies when green horn engineers do not "design for manufacturing" as we call it. We are specialists in that field and get to see all the mistakes that come from an idiot of an engineer that thinks that just because their computer can generate a model for it, "the cnc machines must be able to make it". After all, don't you just hit the button and it spits out parts???
 
While i am sure the TM is light duty...but also take into consideration that chances are good the machine has been pounded on.


I have worked with some Students from a similar background...what was learned at school brought them back several steps from where they should have started. Tons of bad habits and little knowledge. What I saw is "Just get Er Done" and to hell with the Tooling, Machines and if the part comes out wrong...Just make it work anyway.
 
The one thing that made my tongue fall out of my mouth was when we noticed all the retention knobs were loose. Our group indicated their instructor told them to finger tight them only...... Needless to say, we friggin tightened them on the tools we used.... They then got another lecture about knobs, holders, pull force, and price of spindle. Knob breaks loose, and takes, tool, holder, part, and spindle with it. NOT worth it....
 
fair

It sounds to me like you ran into a poorly leveled and maintained machine. Do you think it is fair to put the blame on the manufacturer?
 
I would be willing to wager my left nut on it.... Even though I could not be certain, I know the machines were professionally installed because no one knows jack about machines there and I have not see too many university shop floors less than 6" thick.

I think it is a pretty fair assumption to say they do not handle a 3/4" cutter in Al very well IMO. They did machine a decent part and it was to size so all I was saying it is chewed with it's mouth open.
 
Viper,
I completely understand your frustration. Cavemen with lasers, sad waste of good money. Help the ones who listen, I have several grad students that were hired for there practical skills learned in my shop, they quickly out classed their peers. Our schools are not teaching "blue collar" skills - we need them now more then ever!

Keep trying, it is making a difference!
 
I don't know, we have a ten year old TM1 and it runs a 3/4 end mill in aluminum really well. I'll run a 3/4 end mill 3/16 deep and full width, with about a .0045 chipload, and it cuts nice and smooth. If the cutter wasn't the greatest, I would suspect that. They only weigh about 3500 pounds, so you can't run them like you would a VF3, but they are really nice machines.
 
It is very possible that you can find a sweet spot that they like to run at as well as cutters that they like. We ran high end streakers that are Al hogs. Would rather push a 3fl but without coolant and pocketing, that would not have been a good decision.
 
We sponsor one of our local universities for race part design, mfg, etc. We decided to take a part in and supervise them running it in their place. We programmed very conservative understanding the TMs have about 5hp or so. I cannot remember the exact cutter engagement but I was really shocked at how much the machines vibrated. We ran a 3/4 2fl dry in Al. Approx engagements were maybe 3/8 axis, 30% radial.

The spindle seemed to be handling the load fine but the vibes were surprising. I really thought the TMs were pretty close to a naked VF but I was wrong. We had a Tree knee mill that was quieter than these.

Now, I realize running more flutes would help as well as possibly using a better cutter all around but this was an educational shop so everything gets broke..... I watched another guy trying to drill press a 1" hole at 1500 rpm in steel with a really long bit.... I had to reach for my ear plugs and when I commented that they needed to slow WAY down, all I got was "we are in a hurry". I think they went through 3 bits for one hole....

I had a TM1 for 3 1/2 years. I have to strongly disagree with your statement that the TM1 is no good. You need to run it the way it was designrd to be run. I used mine to cut 718 incinel and 6/4 titanium. You just need to do it right. You can't put a 3/4 inch end mill in and expect to hog a lot of material. The machine just won't do that. It will however work great if you keep your cutter size down to .500. A 2 inch fly cutter removing .050 material works fine, but don't try to take a1/4 inch. The machine just won't do it. For a prototype mnachine the TM series milling machine machines can't be beat.

That's my 2 cents worth.
 
Sorry for not reading every reply, how would you compare the performance to a Bridgeport 3 axis? I have thought that some day I would like to have one as a support machine that could be used for some light machining to the bigger machines.
 
We have Bridgeports and a TM2 and the latter is way more powerful. I'm sure it's less powerful that a VF-3 but it's a very good prototyping machine.

I do wonder a bit about floors though. We are on a floor which was originally designed as a vault for an X-ray machine for cancer treatment. The adjacent vault got dug up and it was literally two feet thick on the ground floor. Our TL-1 and TM-2 work great and the floor may be a factor. It's funny how you hear about some of these units that seem to perform poorly where most seem just fine.

R
 
I would say it is about finiding the sweet spot. I have a TM3 and was not very impressed when i started running it. I ran too large of cutter and it vibrated like crazy. I mainly cut aluminum but also some 4140 annealed.

I tried the 3/4" cutter and had to run it very slow to keep machine together.

I have since swithced to 3 flute Zr coated 1/2" endmill for aluminum and 5/16' Zcarb AP from SGS for the 4140. My metal removal rates on the 4140 were higher with the smaller endmill since I could push it harder.

Ran it at 4500RPM - 40ipm - .600DOC - .080" stepover on 4140 annealed.
 
I had a TM1 for 3 1/2 years. I have to strongly disagree with your statement that the TM1 is no good. You need to run it the way it was designrd to be run. I used mine to cut 718 incinel and 6/4 titanium. You just need to do it right. You can't put a 3/4 inch end mill in and expect to hog a lot of material. The machine just won't do that. It will however work great if you keep your cutter size down to .500. A 2 inch fly cutter removing .050 material works fine, but don't try to take a1/4 inch. The machine just won't do it. For a prototype mnachine the TM series milling machine machines can't be beat.

That's my 2 cents worth.

Exactly my 2 cents as well!

Ever hear the one about the guy who buys a new car, drives out of the dealer's lot at 60mph straight into tree, gets out of the car and says "This car's CRAP!" ?
 
It sounds to me like you ran into a poorly leveled and maintained machine. Do you think it is fair to put the blame on the manufacturer?

We bought a new TM, had them set it up. The table wasn't flat, nor were the axis' orthogonal. Our badly abused and thoroughly worn out Chinaports had more rigidity and power. We sent the POS back to Haas.

I'm guessing some folks have better luck than we did. Obviously we aren't alone though.

Doug
 








 
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