Nikken NX5 spindle speeder duty cycle and temperature questions

Thanks in advance to anyone who can shed any light on this. I have done a fair bit of searching online and can't find anything.


I bought a used Nikken NX5 CAT 40 mount mechanical (planetary gear) 5:1 spindle speeder with max output of 20k rpm. Cooling is all by air.

I have no idea how old this thing is. It appears to be in good shape and runs smoothly.


I found a PDF manual that appears to be the correct one for my model at:

http://www.lyndexnikken.com/images/files/file/Toolholders-Instructions-Manual/Spindle Speeder.pdf

Page 13 of this document addresses heat generation, but the information they give leaves a lot to be desired. For instance, it says that you can run it at 18-20,000 rpm output for 30 minutes, but that you have to have a "cooling air blow" (they show this as an air stream directed at the body of the speeder). Presumably this means 30 minutes per hour, or 50% duty cycle.

My question is, how hot can this thing get? I am running a part that takes about 5 minutes, so I should be able to run several of these in a row before having to let the speeder rest. However, after even one 5 minute long part cycle, the speeder body is over 150 degrees F, even with the "cooling air blow". I have been using my flood coolant to pull the heat out by directing it at the speeder body (being careful not to get any coolant into the seal areas, and blowing excess coolant off gently before running it again), and I can get it back to room temp in about 3 minutes.

Before you ask, there is definitely grease in it.

Aside from the duty cycle that they give, there must be some kind of reasonable maximum temperature that this thing can be subjected to, right? I have a LOT of these parts to make at their 5 minute cycle time, so if I don't have to be waiting 3 minutes between cycles I can save myself a LOT of time.

Any input will be greatly appreciated!

-Jon

Manual says 35c above ambient maximum temperature. Given a typical 21c ambient that would be 76c or 76x9/5+32 = 168.8F. Heat transfer rate is a function of temperature differential, so as the temperature goes up more heat can be disappated to the air. If it is only at 150F then it shouldn't be a problem. Blowing air across it keeps the differential high. A ring of air nozzles around it might help as well.

Hi Gary,

Yeah, now that you mention it, it is right there on page 10 of the manual I linked to before! A serious case of RTFM, I suppose...

Math/conversion question: 21C + 35C is 56C, no? That is only 132F. That being said, it is really hot here lately and my AC is only keeping it to about 75-80F in the shop (let's call it 26C). So, my max temp should be 26C + 35C = 61C, or 141F.

I am having a hard time getting a solid temp reading on this thing with my non-contact IR thermometer. The black top part gives me the best reading, and the most I was seeing was 130F, though it was definitely getting too hot to touch so it had to be at least 140F.

Either way, I bought a 40k rpm air turbine spindle, and have the Nikken as a spare, for now.

-Jon

Oops, senior moment on the math! So what do you have for an air compressor to run the air turbine? I suspect your compressor could take a beating and run up up a serious electric bill.

Hi Gary,

I have a 15hp Ingersoll Rand screw compressor, so I am not too worried. The spindle wants 14CFM and my compressor is rated to 60...

So far so good with the turbine, so I'll keep my fingers crossed!

-Jon

wozzwinkl said:

I bought a used Nikken NX5 CAT 40 mount mechanical (planetary gear) 5:1 spindle speeder with max output of 20k rpm. Cooling is all by air.
I have no idea how old this thing is. It appears to be in good shape and runs smoothly.

-Jon

Click to expand...

Jon, do you still have the NX5? Have you used it since obtaining the air spindle? How do you like the NX5 at this point? I am curious because I am considering one myself. Thanks.