What are the pros and cons of the Milacron Arrow 500. . . garage shop

Hi:

I hope this is the right forum for this question. Let me know if I need to repost.

I do one-ofs and prototypes. I have been on the lookout for a smaller vmc that will replace my manual mill. However, the Milacron Arrow 500 is one that I can't find reliable information or history on from my buddies in machining.

I found an Arrow 500 with control techniques controller (never heard of this one) built in '94. I was wondering if it is applicable for my small operations and how it compares to the last production years of the BMC 20 from Hurco. For instance:

What about tolerances?
How reliable are the spindle and bearings?
How reliable is the ATC?
What is the availability of parts, especially boards and steppers/servos?
Does Milacron still provide support?
If you have any knowledge about this controller; does it even compare with Fanuc and or Hurco's ultimax or on the negative side, Yasnak?
How temperamental is this machine when it gets intermittent use?
Is rigid tapping and wiring for a 4th axis install typical for this model?
Are there any issues that you are aware of?

If you can push some info my way I'd really appreciate it . The cost (without rigging or shipping) is in my budget of 12k or so.

Thanks!

4 big minuses
1) Cincinnati is no more and support is really expensive.
2) Some parts like drives are specific for that particular machine, so buying spares on e-bay my be just a vaste of money
3) Very bad flatness along the X. The X linear rails on that machine are on top of the guides (like on a knee mill) When table moves along the X, center of mass is shifting causing table to rock.....i am effin serious....in my case was around Z would wander 20thou... yes 0.020"!!!
4)Rigidity is not good. The frame is fabricated out of steel sheets and welded together. Column is simply bolted to the bed.
5)Depending on what spindle is in there.. if its pre-greased for life. then the life itself is about 10000 hours for brand new until it seizes up.

zero_divide said:

4 big minuses

Click to expand...

I don't know if they are as bad as ZD here has made out, but the control techniques control is a retro, and not a common one. The 94 vintage arrows had 850's I think originally, the 2100's started in 1995. 0.020 rock z height in the x table would be a repairable mechanical issue, but might take linear rails to correct. If you expect it to keep up with a manual 50 taper mill from WW2 keep looking, no 40 taper machine will do that. The column is held down with taper pins and bolts....usually mogliced in place at tram.... original tram anyway. One of three of my larger machines I have had the column loose and rescraped it in bolting it down steel on steel. The permanently lubed spindles will go more than 10k hours.... at least in my experience, but it depends how hard you drive it.
biggest downer to me is the control, no help from cinci/mag on that control.

The machine with pre-greased spindle we have is around 19000 hours.
In that time we changed whole spindle once and after another 9k we changed all bearings. so around 10k for a spindle. We run machines at max rpm unattended sometimes 20hrs a day. that may be the issue too. But other auto-lubed ones are still going... soo....

The design of x linears is flawed and table will be perfectly flat for only like 2 months after you replace everything. Both our arrows are really roking, but bosses don't have patience to fix them.

Again in places where ppl care about their equipment those problems may not be as rampant, but i believe they still will be.

Hi psient.
I have a 95 arrow 500 with the same FNC control techniques controller. I had it in my 1st garage for 5 years and in my new garage for 2 years. I use it about 20 hours a week. I have not had any spindle or ATC problems as of yet. I had the x axis drive sent to radwell for repair once, which was $1000. I've replaced the crt with a flat screen. I ran it on a rotary phase converter for 5 years; it didn’t like that, but had no choice. I have it on true 3 phase power now and it has less problems.
The control uses fanuc g code. I use mastercams haas post processor for my programs. Today the z axis screwed up, I'll be asking for some help in this forum when I'm done here. It holds .0005 tolerances no problem. It's not a rigid machine that’s for sure. I mostly cut aluminum. Mine has rigid taping, but no 4th axis drive.
Overall a good garage machine if you have true 3 phase power.