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Swing Blade Tension4/7
We operate a Peterson 10" WPF sawmill doing 30-50MBF each year. We Mill in hard species like Bur Oak, Osage Orange, Walnut Crotch etc and have experienced great difficulty in keeping this mill cutting true in all conditions, especially milling Osage Cants lately.
We have experienced the blade wanting to dive in deep horizontal cuts, and wander side to side in our 6-10" deep back cuts. We have adjusted the mill carefully.
I am wondering if it is a blade tension issue since our blades are 3-5 years old and though they are sharp, our sawdoctor does not offer tensioning so we are going to mail one of the blades off and see what happens when we get it back.
Have others experienced difficulty with these mills? At the end of a full week running our mill right now you feel like someone gave you a good beating...
I run a Lucas Mill, and yes I have run into similar problems, mostly with White oak, although I can imagine Osage is as bad or possibly worse. Tension in a log can be reduced by rolling the log 180 degrees, although on a swing blade mill that's a little more difficult than many band mills. Try doing your cut in several shallower passes (i.e. if you are making an 8" cut, try doing it in two 4" cuts). Occasionally I have found the worst tension in the first cut as I open the face, and after that it's not such a problem. Some logs don't seem to be mill-able, -I had a 20" white oak log and after cutting off about a 3" thick face the entire log bowed upward about 2" -Amazing to watch! In the end, what makes milling interesting is to figure out how to make things work out.
As far as I know the blades are hammered flat so no tension problems.
With a Lucas the one pass horizontal cut is limited to about 6" because of the saw geometry. The blade should be tilted down slightly. It's in the book.
Wear and tear on the trolley thewheels/bearings can cause the carriage to skew when pulling the saw into the cut as can pulling from different points on the saw trolley. More so when the wheel grooves get excessive wear.
Drive belt slippage can really cause the saw to cut weird.
If the blade is sharpened wrong, slanted top surface on the carbide. it can cause the blade to pull to one side.
Gullet shape on the blade has an effect of sawdust ejection and is a normal wear and tear feature on all circle blades. The inner surface needs to be square to the flat of the blade. Your saw doctor should be on that.
Over heating can cause blade warpage and can cause miss cuts. Is the water flowing enough?