Haas Toolroom Mills: $5000 for 4"?

[61SedanMan]

I am about to purchase a Haas toolroom mill. I am torn between the TM-2 and the TM-3. $5000 is alot of money for an extra 4" of Y axis, IMO. I am curious what you guys think. Also, I would like to know what owners think about these two models as far as rigitity cutting steels, part repeatability......you know..the works. Thanks.

[DSL PWR]

Well I only have a tm1 but the drives and spindle are the same on the tm series, and I'd think rigidity woul also be comparable. I cut steel plate, 1045, 1018, and a little 4140. I can slot with a 3/4 insert mill .1" deep at 18-20 ipm, and shoulder at .1" deep and up to a 1/2" pass at about 30ipm (60-75 % spindle load @3055 rpm). The tool and spindle will do more but the machine starts to vibrate when you go much past that. In aluminum (6061) I can go as deep as I dare and bump the feed rate up untill my spindle is %100+ (.2 slot at about 100-120 ipm). I've bumped the spindle up to 6000 rpm.

I find it's repeatability as good as your setup. The best job to show this was some large pillow blocks I had to interpolate out to a -.001 press fit. I needed to go 3.25 deep, about 6.5" dia, and once I had the tool dialed in I did 6 blocks and needed to tweak the tool offset once (.0005).

Flood coolant on these machines can get messy. The back guard leaked like mad, and the Haas tech used a pop can to make a coolant tent over the y axis limit. A tube of silicone got most of the leaks down to drips. Once you admit to yourself these aren't enclosed vmc's the factory coolant guards do a pretty good job of keeping the mess contained.

Do you need the extra 4"? Are you sure? Extra travel is always nice. If you decide on a tm2 get the tool changer (also recomended on the tm3), you are probably like me, and thought you can live without the extra expense. This changed when I did 300 changes in about 5 hrs... Even the manual tool change is better than screwing around with an r8.

Whatever you decide these tm's are a great bang for the buck, you just need to work within their limits. Make sure you have a good tooling budget to get going (they are more expensive than drugs). I've had my mill for about 8 months and have about 10k in tooling now.

Good luck