Hydraulics stopped on LT35HD - turned out to be easy fix

[WV Sawmiller]

    It has been a couple weeks since I cut anything so I cut a big tulip poplar yesterday and cut a 16" diameter 14' long log off to get 4 more 2X6's I need for rafters to finish my lumber shed and for a customer who just needed 70 bf of 7' lumber. Normally the 7' would be a pain but worked well with the 14' I could just cut in half.

    Rolled the log on the arms and it lifted easily then arms would not lower nor would the other hydraulics work. Went and got the manual and cell phone. Was going to call WM but troubleshooting said make sure head was forward on the power strip (it was) and mentioned ground issues so just for giggles I moved the head back and forth a few inches. Everything worked fine after that. Evidently some moisture or sawdust or such was blocking contact on the ground and easy fix. Not sure why it even worked at the start.

    Went ahead and cut my log with no problems. Got my rafters and about 86 bf of side lumber which is more than enough for my customer plus a little. Not super yield out of the log but had a little flare and sweep but still provided what I needed.

     I still have the butt log and second section up in the woods plus will get some wood, even if only stickers, out of the top. Meanwhile the deer, my horse and mule are enjoying the green leaves.

[Ralph]

I have the same issue with my 2013 lt35. My power strip is only 16 in long. The contact  causes dead areas on the strip. I do not know why, as it makes good contact with the strip. I end up sanding the strip clean and the hyd work fine. Any advice as to why this happens is welcome.

[Dave Shepard]

One thing to do is be sure the head is stopped before using the hydraulics. If the head is moving it will arc and you will get dead spots.

[Chuck White]

Good point Dave!

I was having issues with my LT40 a couple of years ago, cleaned the power strip then stopped head movement anytime the hydraulics were used, no more problems.

[Brucer]

Moving the head while running the hydraulics causes arcing. The arc burns a small pit in the copper strip (and the brass shoe). Next time the head is parked on top of one of the pits there is more resistance. When you're running a motor, more resistance = less voltage to the motor = more current through the strip. The pit gets worse. Eventually you have s copper strip that's so badly pitted it can't be polished.

Corrosion also increases resistance = less voltage = etc. Ditto for the negative shoe on the bottom rail.

A quick pass over the contact surfaces with emery cloth one or twice a year makes a huge difference. It also means longer brush life in your motors.

I found it also helps to increase the pressure of the shoe just a little (disconnect the battery first!). I've got mine just tight enough that the shoe polishes the copper strip. Now I just have to use emery on the bottom rail.

If you have to move your head to a different spot to get your hydraulics working, time to attend to the contact surfaces.

[WV Sawmiller]

Thx for the info. I'll check my strip. I only have 78 hours on the mill and its hard to believe there could be that much wear and tear on it. I don't think I have been using the hydraulics while the head was moving but I will certainly be real diligent in the future not to do so.

[Ralph]

Does leaving the head parked on the contact strip when not in use cause issues?

[Dave Shepard]

You would have to have a problem in the hydraulic box for there to be issues. If you had a draw in there, I think you'd know about it pretty quick. My mill has been parked on the strip when not in use since it was delivered. No problems.

[Brucer]

The copper strip will oxidize over time -- regular use wipes the corrosion off (provided there is enough pressure on the shoe). Salt will accelerate the corrosion if you're near the ocean.

On older Wood-Mizers the shoe was connected directly to the battery. If you left the head at the front over the contact strip, the strip would be live even with the ignition switch turned off. Anything conductive (such as sawdust) that connects the contact strip to ground will let current flow through the shoe and increase corrosion (and also drain the battery).