Bandmill Tuning Basics

A beginner gets the Rx for wavy cuts. June 12, 2006

Question
I bought a 36" Hudson bandsaw mill. I can't get it to cut straight boards, especially from smaller logs. Does anyone else have this problem with sawing, and know what to do?

Forum Responses
(Sawing and Drying Forum)
From contributor P:
I have the Hudson Oscar 30".

Wavy boards can be caused by:
1. Blade not sharp (try a new blade).

2. You are sawing too fast (slow down, especially if you see a knot coming up).

3. Improper blade tension (read the manual and do the Flutter Test with the guides moved out of the way. You can get wavy boards if the tension is too high, or too low).

4. The guides are adjusted wrong. You need about 3/8" between the back of the blade and the roller guide, so when you are pushing hard, the blade just hits the roller. If you have the ceramic guides, take a putty knife and make sure there is no pitch build-up (do this every day). Also keep the guides as close to the log as possible.

5. You can also call Woodmizer (who make the blades for Hudson), and get them to send you a blade with a different pitch or hook angle (ask for a blade consultant). There are other blade options out there for frozen wood, of different species. Also, sometimes the first cut into the log (on small logs), or you are taking a thin slab, does sometimes come out wavy, even with the precautions above. I will sometimes rotate the log an extra time (at the end) and skim off 1/4" to take out the wave from the first slab.



From contributor K:
We have an Oscar 36 also and the remedies that Contributor P described are very accurate. Except from our experience on smaller diameter logs (8” or less) when brought into the third cut of the Kant. The dogs twist the smaller Kant into a trapezoid angle. We are currently experimenting with two 8” C-clamps attached to a ¾” diameter pipe that will hold the smaller Kants at the proper position. The clamps are placed just before the dog and toe board assembly across the width of the bed.


From contributor A:
To the original questioner: You didn’t say if you get wavy cuts or boards that are not straight, the wavy cuts have been well covered, if you are getting tapered boards check the bed for level. I had one side near the end sag a 1/4 inch and made boards that were thin on that end. Cut short logs fine but when I cut long log the carriage would drop at the end. The log stayed clamped flat because only the end sagged. Kevin my log stops got out of square after awhile, so when I turn the first quarter turn I check the flat side with a level and tap a small wood wedge to hold it vertical


From contributor J:
I have a 36" Hudson farmboss. The blade tension should be set 30 to 36 lbs of torque. Your blade guides might be a little lose - loosen them up and put medium pressure with your thumb and index fingers and tighten them with an allen wrench.