Z Trucking Heating

[jstone]

Does anyone know if a faulty QC could cause the Z truck to heat up? After about 10 minutes of carving my Z truck heats up to the point that I can not hold my fingers to it. All seems well. The ring on my QC does not look parallel with the rest of the Z truck and I am wondering if this would cause any vibration that would cause it to heat the Z truck. The QC itself does not get hot nor does it appear to hold the bits loosely. It seems OK.

Thanks in Advance

[ChrisAlb]

Does anyone know if a faulty QC could cause the Z truck to heat up? After about 10 minutes of carving my Z truck heats up to the point that I can not hold my fingers to it. All seems well. The ring on my QC does not look parallel with the rest of the Z truck and I am wondering if this would cause any vibration that would cause it to heat the Z truck. The QC itself does not get hot nor does it appear to hold the bits loosely. It seems OK.

Thanks in Advance

Hi jstone,

It shouldn't be getting so hot you can't touch it for sure. If the chuck and flex shaft aren't getting too hot, I'd take a look at the spindle bearing. Pull the flex shaft out and spin the chuck by hand. It should be very smooth and spin freely with no "rough" spots or clicking noises.

What type of material are you carving and how deep? Harder woods with deep carving/cutting will cause things to "warm" up a bit more but still shouldn't get "too" hot.

Also, the QC collar "should" be straight. If it's not, you likely have dust and chips in the chuck that should be cleaned out. Otherwise it WILL cause damage to the chuck and or bit adapters.

Hope that helps

Chris

[jstone]

Chris
I am doing some plaques using centerline, 60 v groove bit in maple. The bearings turn smoothly with nothing happening to make me concerned in that area.

[ChrisAlb]

Well that certainly shouldn't be making it work very hard. OK, if the bearings are good, how about the truck bearings. With the power off (at least 20 seconds) Move the truck by hand up and down (Z direction). You should feel only a minimal resistance and again, it should be smooth.

[Jeff_Birt]

Sounds like you flushed grease out of the top spindle bearing by using too much flex shaft lube to me. I did the same thing. If there is something wrong with the chuck your bit will wobble and it will show in your carving. You can check the top bearing by taking the 'top hat' off the Z-truck and carefully pulling up the rubber seal on the bearing. In my case the ball retainer had disappeared (got pulverized).

[Kenm810]

Just a couple of thoughts,
Have you lubed the flex-shaft recently, after running the first project I pull the the shaft connector out of the top Hat on the "Z" truck to check for any lube that's not supposed to be there, I’ve read a few posts say the any extra lubricant may leak down to the spindle bearing and damage them. Also I’ve had the bearings corrugated metal spacer sleeve drop out of the carving head and fall between the traction belts, I found it in the Down Draft dust compartment. The bearings turned smoothly but the QC Chuck and Bit wobbled a little. I had to send the machine to Texas for that one.

[jstone]

Chris,
The z truck moves up and down snugly with a fluid motion. I dont think there is any concern there.

Jeff & Ken
I have not lubed my flex shaft for quite awhile. It barely gets warm. I will have a look at my bearing on the top to see if I have a retainer left. It does seem that the heat begins on the top half. My carvings are top notch since my QC does not wobble and turns smoothly.
I will have to take a look a little deeper to see if I can find anything that does not look right.

Thanks
Jerry

[Digitalwoodshop]

Ken hit the nail right on the head..... Picture a cooling fan running at full speed blowing air. Now dip that fan into a tub of water and hear the motor and fan slow down and get hot and blow up..... The difference is air is easier to push than water.

Now the Spindle Bearings racing around the track at thousands of RPM's.... No Problem..... Now you over lubricate the flex cable and the excess oil migrates down to the dust seal of the spindle bearings and into the bearings. Removing the 2 screws from the Spindle top hat will reveal a dry bearing top or a bearing with oil laying on it, seeping into the ball bearing area. Now picture that thick oil being like the water and acting as a resistance to the ball bearings racing around inside the bearing. It goes on like a blender and the oil and the bearings get HOT and the oil eventually turns to GREASE thickining.... You come in to find your Spindle VERY HOT and wonder why....

I learned this the hard way too as did many others.... The grease gets so HOT it gets hard and you have heard of Rail Road Cars having the Bearings catch on fire..... They even have Heat Detectors along the Rail Road Tracks that trigger a alarm as a hot wheel passes.... Same with your spindle.....

Clean the oil from the top hat and call LHR. It will only get worst from here out.... The only real fix is a Spindle Replacement or Bearing Replacement..... I have not even attempted the Spindle Bearing Replacement YET.... Still waiting on 2 back ordered Bearings that fell through the cracks at Christmas.....

Good Luck.

AL

[jstone]

I was talking to the people at LHR and told them my problem. They were very helpful. Instead of sending my machine to them, they sent me a new z truck. I finally got the time last weekend to swap the new one for the old one. What a difference!! My machine is about half as noisy as before and now there is no heat to speak of!! Everything looks good on the old one except the QC. It looks like it might cause a vibration since the ring that lifts up to loosen the bearings so as to install a bit holder is not parallel with everything else on the z truck. Thanks again for the excellence in customer care at LHR.
(PS - I did not find it hard at all to change out the z truck following the posted instructions)

[Cbrown]

Just talked to LHR about my Z-truck overheating, but they told me they won't sell me a new z truck. Has to be installed by one of thier techs. Other then losing the machine for awhile, he was very helpful.