Wavy cuts on the sawmill

[westisthebest]

This is a question for those who actually know what they are doing. I have been using the lt40 woodmizer and several of the last logs have been real wavy. I was curious what the fixes might be. I am cutting pretty big(32" wide) white oak. The blades are old but were resharpened. I didn't know if new blades would be that much better. I cut up a cedar tree in the middle of the oaks and had no issues, thought maybe because it was that much softer. I got a lot more to cut up and I don't want to take a chance at screwing more wood up. Any help or advice I would appreciate.
Thanks, Chad

 

[FredP]

when they were sharpened did they re-set the teeth? if there isnt enough set they will heat up.

 

[TBradley190]

A buddy of mine has a woodmiser and has cut alot of lumber for me and I have helped him out alot over the years. When he cuts soft wood such as pine, cedar, juniper, and cypress he has an optimal speed that it can feed well and produce flat cuts, but when it comes to hardwood such as oak, walnut, and hard maple he has to slow down the feed if not the blade will wonder no matter the tension. But he does his own sharpening and tooth setting and I know that has alot to do with of course. But you may want to try a new blade and slow down a bit and see what happens.
Good luck with it

Tim

 

[CrealBilly]

a wavy cut can be the result of a a lot of different things - but have you adjusted the drive belt tension? If the drive belt slips at all during a cut - you'll never get a straight cut no matter how slow you go. Check the maintenance manual - it give the directions and specs to tighten the drive belt.

 

[sawman101]

I had a sharpening shop for many years. I did a large volume of sawmill bands for many different sawyers from several states. The main cause for wavy cuts in lumber is attributed to set. Having more set to one side causes the blade to either dip or climb in the cut, then because it can only travel so far, flexes back the other direction. I used the Timberwolf semi-automatic setter with excellent results. Less costly, and slower is the Cook's Cats Paw setter, but is very accurate. Also, you may consider positioning the blade further back on the band wheels. The teeth do the cutting, not the band body. When the teeth project just in front of the wheel, the leading edge of the band, the teeth, is less stable in the cut. Ideally, the teeth should be at the apex of the crown. This works on smaller width bands, and I think the same principle will work on the 1 1/4 bands too. Less tension is also needed when set up that way, which reduces tension on the tooth set in contact with the wheel.
I'd really be interested in knowing the results. Good luck, and happy sawdusting!:saw:

 

[westisthebest]

I think that dull blades were the culprit. I found a blade that had been resharpened but not used since and didn't have a problem with it. Maybe it was sharpened different or better than the other I had been using. I am just going to take the rest to be sharpened and maybe get a few new so I will know if they are wavy now there is something else up. Thanks for the responses.

 

[CrealBilly]

I think that dull blades were the culprit. I found a blade that had been resharpened but not used since and didn't have a problem with it. Maybe it was sharpened different or better than the other I had been using. I am just going to take the rest to be sharpened and maybe get a few new so I will know if they are wavy now there is something else up. Thanks for the responses.

Don't forget to check the tension on your drive belt, I was getting about 200BF out of a new blade before I had to change it because it would start to wave. After tightening the drive belt it was back up to about 1200 BF, best part I got some extra mileage out of the blades I changed out @ 200 BF. According to WM you should check the drive belt tension every 50 hours of operation. Here's a link to the specs from WM