Sawing Large White Spruce

[woodpecker]

Been out cutting some timber to build my garage and workshop, Fir, Tamarack, and White Spruce. I have no problem sawing all the other species of wood getting excellent results. The white Spruce is a problem especially the large ones, getting wavy cuts. I've been sawing the dimensional lumber over sized then Re Edging it on the mill to get strait edges which is more work but the thickness is still wavy and I don't like it. I've tried everything I can think of 7/8 pitch 3/4pitch 10 degree hook angle 8 degree hook angle more set keep checking the blade tension, it's getting a little frustrating. Any one else have this problem and found a solution? I need help any suggestions would be appreciated. Thanks in advance for your replies. ??? Phil

[woodbeard]

Hi Phil, welcome to the forum
What sawmill do you have?
Softwoods can be especially problematic in this way because of the difference in hardness between the knots and the rest of the wood.
Afraid I cant help too much, but hopefully someone else will- I still encounter this problem myself. Usually in larger logs, like you say.

[kderby]

Hi Woodpecker,

I have the same issue with large Engleman spruce on a band mill.  The knots or even a change in the grain will make a wave.  If I go slow, it seems to help.  Not every tree or cut "warbles." I think you'll just have to take it in stride and accept that this is rough sawn....literally ;D

[woodpecker]

Thanks for the replies, I'm using a Thomas mill with a 20 horse V twin. Never had a problem like this even in hard woods. I hate to think I may have to just accept this, kinda proud on the product I've been making. I have a suspicion heat could be the problem causing the blade to stretch and detensioning through the cut. Any one have any ideas on extra cooling? Thanks Phil

[RENOVATOR]

I am sawing spruce also.  I am running 2k on the blade tension, mixing dawn, veggie oil and water as the lube and brand new blades(changed every 200bdft).  What I've found is that the blades right out of the box will minimize the wave and as soon as the wave starts to get unacceptable, I'll change the blade and write "Spruce" on the blade with a white grease pencil.  I can then take that same blade, sink it in to any hardwood and easily get another 700 bdft out of it, so there's not really a downside except for the time invested in blade change.

[leweee]

 
Large knot Norway Spruce & hibernating Clarke mill.                                                                                                                 

Things I have learned sawing spruce with big Knots.
    Feed from the butt end towards the top ( limbs on an angle in the log)
    20 thou. minimum set per side.
    Slow feed rate at Knots
    Extra lube at big knots (over 2" in. dia.)
I use 3/4 pitch 10 degree hook with bar oil & kerosene lube mix

[thecfarm]

Another member from Maine and he has a Thomas mill.Welcome to the forum. I have one too.I think the blade pitch has alot to do with it.I sell all my spruce to the sawmill now.I tried to cut a spruce once,I won't do that again.I had move waves and bad lumber than I ever seen.Don't think I got one usable board out of the tree.I threw it on to the burn pile before anyone could see it.I can saw anything else on my land and it comes out real nice.I just have a pepcock to adjust my flow.Open it all the way,that will give you some coolant.I usally only let mine drip every few seconds.The spruce that I tried was only about a foot through,small for my trees.I hace cut some big pine and hemlock and have had hardly any trouble beside big hard knots.That spruce was a bear.I could not see no reason why that was being that way.I changed blades thinking that it was dull,same results.I slowed the speed that I was pushing the blade through,same thing.The knots were very small.I don't think they was even ½ in size.I sawed through bigger hemlock knots than that at a good rate of speed.Seems like someone was on here awhile back and they set thier blade at a cetain pitch and it worked for them.Good luck.

[Percy]

I cut lots of Engleman and Sitka spruce up here. What Ive learned is to use HUGE(lubemizer wide open) amounts of water/blade lube.  Also around 30 thou set(need HP but it works for me)helps. If you can cut them green as opposed to dry, you'll have much more sucess getting waveless lumber. Also, change blades as soon as they lose their "wow" factor.

[SwampDonkey]

Maybe some Maritimers can pipe in here. I see all kinds of spruce and cedar cut on portables. Looks nice to me, so there must be a technique involved. I even seen 3 year old spruce full of sawyer beetle holes cut up and used for a barn/loft.

[LOGDOG]

WoodPecker,

   Call WoodMizer and ask them if you can "try out" one of their 4 degree hook angle blades. I've used it on Spruce and got zero waves. Wide set will help too. If you end up resharpening the blade yourself, set it to .030 - .032 first and then "kiss sharpen" lightly. That will give you razor sharp teeth - sharpened to the angle they'll be cutting at. Love that 4 degree blade!!!!!

LOGDOG

[woodpecker]

Thanks again guys for all the input.
LOGDOG I sharpen and set my own blades my own blades will try that hook angle. Were you using that hook angle on a 3/4 in pitch? That may not make much difference, I let you know how I make out. It's a shame that white spruce is so hard to cut it's one of the best framing lumber species out there when you consider the strenth to weight ratio. JMO. Thanks  Phil

[spencerhenry]

i have cut alot of big knotty blue spruce. and alot of engelman spruce. engleman mills way better than blue, usually because the knots are smaller, and fewer of them. i dont like milling blue, mostly because of the hassle with the knots and wavy cuts, but there are other reasons also. but there are a few things that i have found that allow me to mill big knotty blue spruce with high quality results. 1. the blade must be SHARP, i dont mean kind of sharp, or pretty sharp, i mean cut you to ribbons if not useing gloves sharp. 2. the blade guide rollers must be set up PERFECTLY, and checked every time the guide arM runs into a log end, or branch etc. 3. run the feed slower through the knots. 4.limit the amount of blade in the wood if at all possible. 5. run thicker blades like .055". 6. run plenty of water, i wide cuts i run the pump wide open. 7. keep the blades clean, sometimes after hitting a pitch pocket, i hold a chisel, or felling wedge, or piece of wood on the blade as it is running, scraping off the buildup.
but ultimately my solution was to not ever buy blue logs again. if the logs are free, then i would only mill the ones with small knots. i also toss the 6 to 8 feet of the butt log on the bigger ones, too much shake.

[Brad_S.]

This suggestion won't help you at the moment, but waiting until the log is frozen solid makes them a breeze to cut. ;D

[leweee]

 ;D ;) 8)

[LOGDOG]

WoodPecker,

   When I used the 4 degree hook I was using a 7/8" tooth spacing. It won't matter though if you use 3/4" tooth spacing. It's more about the angle of approach for the tooth so to speak. I love spruce but used to hate to cut it because of the same issues. Once I found out about wide set and a low degree of angle on my hook I didn't have any trouble. I think you'll life it. You need to slow the feed rate just a bit but in "difficult to cut woods" we kind of need to do that anyway. Hope it works out for you.

LOGDOG

[woodpecker]

Thanks LOGDOG will give this a try I'll let you know how I make out Phil