Wood-Mizer LT20

[Silverfoxfintry]

Hello.

My Son David is looking at a second hand LT20 mill.
This will seem like a silly question to a lot of you. But we have no knowledge of Wood-Mizer products.
It apparently is Fully Hydraulic.
Does this mean that it has hydraulics operating the cutting feed? Or do you have to manually push the cutting head when cutting, or is the feed hydraulically operated?

Thank you.

Silverfox.

[barbender]

Hello Silverfox,

I see you are in Scotland. The LT20 is a Euro only model. I'm not well versed in them, but from what I've seen they have similar function to an LT35 or LT40 hydraulic over here. An LT40 always has power feed, I'm not sure about an LT35 hydraulic. At any rate, the power feed is DC electric on ours, I would expect yours to be the same.

[Silverfoxfintry]

Thank you for your help.
After careful consideration we have decided not to proceed.
The mill we currently run is British built Forestor Jacko.
It is fully hydraulic with a separate 7hp engine powering all functions.
On a good day it is a dream to operate. However recently we have been having problems with blade tracking. The blade will not settle on the wheels. Is it possible that excessive water lubrication is causing this problem? A phenomenon similar to "hydroplaning" when a car hits standing water?
Just a thought.
Silverfox.

[ladylake]

 Look  for a bad bearing if the blade wont track .  Steve

[barbender]

I would second looking for a bad bandwheel bearing if it doesn't want to track correctly.

[customsawyer]

Not familiar with that mill. Are the band wheels belted or steel? If belted the belts could be worn and blade is making contact with the steel. If steel then the wheels could need to be recrowned.

[Silverfoxfintry]

The wheels are not belted. I am not aware of any crowning on the wheels.
I am familiar with crowning pulleys for flat drive belts. I was not aware that it was possible on steel bandsaw blades.
I will have a look at the wheels and see if they are flat or crowned.
I am aware of another mill with a later serial number, it has belted wheels.
It was obviously a problem.
It is not possible to modify our wheels to take belts, however it is possible to machine them to crown them.
Can any advice be given about the radius of the crown?
Thanks again for all the help.
Silverfox.

[Silverfoxfintry]

I have managed to find original drawings of the Band Wheels.
They are crowded. Ours are worn. No crowning.
I plan to remove the wheels and get them to a local engineering workshop to get them restored to original specifications. 
Hopefully this will solve the problem.
The Jacko Mill is an incredibly well built machine. It is a single post design. The main beam is a 12" x 6" square section tube, with a 1" thick plate screwed to the top. We have loaded 38" diameter Oak logs and the frame stayed true. No flexing.
It's a pity that, like so many British designs lack of sufficient capital caused the company (Standrange) to fold sometime ago.
Silverfox.

[customsawyer]

How many hours on the wheels?

[Silverfoxfintry]

How many hours on the wheels?

I have now idea. The mill is currently on its third 25hp main engine and the hydraulic power pack on its Second. 
Depending on orders it can run up to 40hrs a week, but 20/25is more normal.
The hour meters that Kohler supply don't last. I do an oil and filter change Three times a year. 
I removed the idle wheel today and double checked the rim.
When using a straight edge it is pretty well perfectly flat.
If anything slightly concave. But less than 0.001".
I will pull the drive wheel on Thursday ( it's a pig to remove)
Silverfox

[Silverfoxfintry]

Thanks to "James Sharp" I have obtained the original specifications for the mill.
The crowning should be 2 to 3 degrees. Meeting in the centre of the rim.
Both wheels are now with the machine shop.
I will update when we have them refitted.

Silverfox.

[jpassardi]

Good to hear.  How's everything in Scotland?

[Silverfoxfintry]

Good to hear.  How's everything in Scotland?

Everything is going well.
After a nasty few days with snow, wind and rain. Today was perfect! Calm, sunny and warm enough to work outside.
Today we refitted the newly crowned wheels and reset the tracking and blade support rollers. Took the chance to level the bunks and the power head.
The crowning seems to have worked!
Did a couple of test cuts on a 24" larch log.
The cuts look perfect and the blade performed better than I have ever seen. 
I am still recovering after my knee replacement so I was only on site for about 3 hrs.

[Silverfoxfintry]

Well.

Twenty odd hours now milling with the crowned band wheels.
It's quite a difference. Once the blade has been tracked it stays tracked. No more wandering blades.
Thank you all for the help and advice.

Silverfoxfintry 

[Magicman]

   Thanks to the value of the Forestry Forum again. 

[thecfarm]

You are   ing now!!!!