Yes. Last Friday I had the service guy out at my place to listen to the machine and debug the problem. He agreed that it sounded like the transmission, but wanted to run the standard test procedure. This involves taking the motor and transmission loose as a unit, removing the cogged belt that connects the transmission output pulley to the spindle input pulley, and running the motor again to see if the noise was still there without the spindle connected. He did that, and the engine and transmission together were quiet as a mouse. He said this pointed to the top spindle bearing as the culprit.
Next he checked the oiling system on the mill. The machine has an automatic oiling feature, so that while it is running every 30 minutes or so it squirts oil out into 16 little "meters" that oil the ways, the ballscrews, and the spindle bearings. These meters are kind of like jets, with really small orifices. Only one of the meters goes to the spindle bearings. The service guy disconnected the oil line going to the spindle and put a little test tube on the end of the line. Then he gave me a program to input that ran the mill table across a repetitive motion so that the oiling system would work with the spindle not running, and told me to run it for four hours like that, and then measure the amount of oil in the test tube. It was supposed to have 2-3 ccs of oil in it at the end of the test. He was suspicious that the meter was clogged and that the spindle bearings were not getting oil, and he was right. After the four hours of the oiling test were up I looked in the test tube and it was pretty much bone dry. Looks like that $10 clogged meter cost me a spindle.
The local service place did not have the correct replacement spindle cartridge, so the service guy got that lined up to ship from Haas in California; it is supposed to be here tomorrow. They are going to call me to confirm that it came in and arrange to install it. I'm hoping that they can get somebody out here on Saturday so that I can be up and running again this weekend, but if not I will have to take a vacation day one day next week so they can put it in. Then, finally, I can get back to machining the manifolds.
I think I mentioned previously that I had purchased another CNC machine to take the load off my old Milltronics machine; this one is another Haas machine, a smaller one called a VF-2. It has many of the same systems as my VF-4, and is about the same vintage. Over the weekend last weekend I thought it would be a good idea to check the spindle oil meter on that machine too. What do you know, it was also clogged! It was not completely blocked like the one on my VF-4, but the 4 hour test that was supposed to result in 2-3 ccs of oil resulted in less than 1 cc. So I had the service place order a new meter for that machine also, and I put that in earlier this week. Now both machines give the correct amount of oil to the spindle during the four hour test.
One positive out of all this is that I have learned a whole lot about how these machines work and how to fix and diagnose problems with them. When the service guy was here he was really helpful in answering all my questions and explaining his answers thoroughly. He seemed like he really knew what he was doing, which I suppose makes sense since he works primarily on Haas machines. The learning curve for me reminds me of when I got started with working on cars. Over time the mysteries of how everything on a vehicle works peeled away, and I got very comfortable doing just about anything to my cars. I need to get there with the CNC machines too...
