How To....interact 4 Ac Spindle Motor Retro

[camarogod98]

I thought i would put a small thread up here for all you guys that have interact 4's but have dead spindle motors or drives. As you all know the interact 4 has a DC spindle setup...when they are working they work great but when they break down it costs mega bucks. The interact 4 is one hell of a cnc knee mill because it has a BT40 spindle and is rigid enough to take big cuts unlike the rigid ram QC30 machines (dont waste your time with these ones) that do nothing but chatter.

I did a complete retro on my interact 4, this included a 4 axis ajaxcnc control and a AC spindle setup. The ajax control is awesome....its the 2nd one i have done and i love the control, its a really good deal for the money. You can use your original SEM motors. all you will need to do is just adapt the ajax encoders on the back of them. I made some nuts to screw on the shaft end and then turned the nuts down to fit the encoder bore, made a spacer so the encoder would fit under the stock cap and that was it. The motors work great...I did the exact same thing on my interact 1 retro and i ran them for 4 years with no trouble.

moving on to the spindle.

I did some research and found out that a Marathon Micromax 10 HP Y996 AC motor ($758 from automationdirect.com) fits the machine. you could use the smaller 7.5 HP motor but you might as well buy the biggest you can. all you need to do is make an adapter plate to bolt the motor onto the stock mount. You will also need to bore your motor pulley out to fit the shaft. Remove the plastic fan from the bottom of the marathon motor and get yourself one of those round thin brushless blower fans (around $100 from mcmaster carr) and bolt it on the bottom of the shroud. You need to remove the plastic fan so you can wind the motor up past its rated speed. the plastic fan could explode and it would also not cool the motor properly at slow speeds.

As for the AC drive. I recommend a HITACHI SJ200 (can use single phase power) or a SJ300 (must use three phase power but has encoder feedback).

I went with the SJ300 drive ($890 from driveswarehouse.com) because i thought i would need the encoder feedback to control the speed better than what a sensorless vector drive would do (SJ200). I am running my SJ300 in sensorless vector mode and it works GREAT, the speed is consistent. these drives have came along ways in the last 10 years.

If i could do it all over again i would get the SJ200 so i could run my machine without a phase converter.

as for getting the new spindle setup to work with your heidenhain control.....I will leave that up to you. I would throw the old control in the dumpster and just get a ajax setup. You will love it!

finding a spindle motor to fit into the machine was a challenge, thats why i posted so you guys could just go out and buy something and know that it would work.

[bherr]

camarogod98,

Can you tell me what HP the DC motor is. I just had mine re-worked and the prolem I'm having is the spindle keeps shutting down in the middle of a cycle run. I just purchased a 7.5 HP phase converter and still having the problem, also the phase guy wanted to know which leg I had the hot lead wired to (T3) I don't have a manual so can you tell me which leg is the hot one. I have a black, blue and red wires coming from the machine to the switch box mounted on the rear of the machine. Its a series II 1985 model year with the Contraves and Heildelhain controller. Any help would be greatly appreciated.

Ben Herr

[camarogod98]

the motor in my interact 4 was 7.5 KW...I think that is around 10 HP. I had to have a 15HP phase converter to power my interact 4 when it had the orginal DC motor setup on it. These machines draw a ton of amps when the motors spin up from zero to speed. You might be able to adjust the accel ramp time on your drive.

If you need another spindle motor i have my orginal (in good working order)that i can sell you for 500. the only thing wrong with my spindle setup was the MTI-1 card was blown.

[UKRobotics]

According to all the datasheets and tech manuals i've ever been able to get my hands on, the series II interact 4 has a 5kw spindle.

When you consider that each axis is rated at ~1kw thats about 8kw which is getting on for 11hp.

A 15hp phase converter sounds about right for one of these machines. I'm not supprised you've been having problems with the 7.5hp one.

[bherr]

Well fellas the motor is a 15HP and I had to purchase another phase converter to handle it. I purchased a Phoenix 7.5 which was too small. Had it hooked up for maybe 1/2 hour and then call Phoenix Phase Converter's and they refused to take it back, so be careful. anyhow if you know of anyone that's looking for 7.5 HP phase converter with soft start, let me know. I'll sell it for $350 + shipping, Paid over $400. + shipping

Ben Herr

[camarogod98]

my motor says 7.5 KW on its tag. I think the interact MKII was 5KW.