Techno CNC lemon

[salmoncreek1]

We bought a CNC 4896 LC Plus Series from Techno Inc. and have had problems from day one with it. Currently we are having a problem with the 1/2" profile cutter progressively going deeper into the sacrifice board with each part it cuts out. I was wondering if anyone might know why? Thanks

[cpsheets]

Is this a new LC with servos or an older one with steppers?

[salmoncreek1]

This machine is new and has the servo. I called the company's subcontracted field service tech and described the problem and he said that it sounds like the Z is slipping on the drive shaft. Because the tool drop off had changed and was off. What do you think?

[RandK]

It's worth checking to make sure that allen head bolt inside the drive coupler housing is tight. Remove the black plastic cap on the side and look in there with a flashlight while somebody jogs until it is lined so you can get a ball end on it. If that is loose the machine thinks the axis is level but it has dropped or raised due to gravity or plunge force. I would think this would be rather random and not just from one part to the next. There should be a document on your s/w install cd that has pictures of that coupling and the spec on the clearance between the halves.

It's usually pretty obvious when its the tool moving in the collet or holder but a loose spiral cutter will pull itself down into the work.

[salmoncreek1]

Thanks for the advise. We actually got the company to send someone out to look at it. I will ask him to look at that.

[Patternboy]

Hi salmoncreek1
I sound like you have the same problem that I got on our CNC router model 5950 from Techno, the Z axis was dropping by itself when cutting a toolpath, I was cutting a 3d pattern and suddenly the Z drop down by 1/2" into the pattern and the CNC kept on running, I was using a .5"x 5"L. ballnose and made a nice groove in my piece, luckuly it was pine, it happen 3 or 4 time after, I called the distributor and they found out that the brake system in the Z axis motor was defective, they replace the motor and never had any problem with it after.

[salmoncreek1]

Patternboy, this is interesting information. As of yesterday Techno had sent someone out and the problem still exists, and has spent an additional 5 hours on the phone troubleshooting and told us that it must be the computer... then decided to send a new cable that goes from the computer to the machine. This has not worked. We are also having a problem with the Y axis returning the tools back to their proper location. They are off by at least 1/4". I will try to suggest this to them.
Thanks

[Patternboy]

Hi salmoncreek1,
like I said I have a RG 5950 and the problem started last march, they finally decide to change the motor for the Z axis in July. I asked them to extend my warranty because I couldn't use the CNC, they gave me 4 months extension.

What was happening is that I was making a 3D complex part, my toolpath was done with MasterCam X2 router Pro, I used the waterline toolpath with a .5" x 5"L ballnose, my stepdown was only .005", I suspected the motor that control the Z axis because the drop happen when the toolpath was making is stepdown, but that time it whent .5" in one shot and the CNC kept ongoing, the next time it happen it drop about an inche but the CNC stop and gave me and error on the Techno interface's monitor. This is the error message;
M3 position error. (Z axis)
No controller power.

Do you get any error message when it happen. If you an error message, ckeck inside the controller unit, on the left, remove panel and below on the left, there is 3 blue cassettes type with green flashing light, if you have a red light when it happen, the motor is the problem.
Do you deal with Techno-Isel from New-York.