"Sapwood Pull" Ruins Sawmill Wood! Part 2 of Extractives Video

[@Zarealy]

Good stuff! Thank you for taking the time to share your knowledge with us.

[@HobbyHardwoodAlabama]

Glad it was helpful!

[@danmaciosekmaciosek6166]

Ive been running a sawmill for5 years now, still learn alot from your videos. Thanks

[@HobbyHardwoodAlabama]

Thanks!

[@knlstam]

Another great video. Look forward to any videos you may do on the topic of kiln drying.

[@HobbyHardwoodAlabama]

Thanks.

[@vincealdrich7960]

Thank you so much for your video channel! I have been watching for quite a while now and have learned a ton. I appreciate your knowledge, personality, demeanor and sense of humor

[@HobbyHardwoodAlabama]

You are welcome!

[@make-somedust]

So all I can say is you’ve forgotten more than I will ever know. The knowledge you share is “Priceless”

[@HobbyHardwoodAlabama]

Thanks! That's one reason I like to film when I'm sawing, I have no idea what will come up in the process, and I can talk about it real time while I'm sawing.

[@MakerBoyOldBoy]

Professor, thank you for the time to teach us, the willing to learn. After soaking in a healthy percentage of your teachings I'm wondering how I made good stuff at all from the Big Box Store firewood I bought for years. One wood stress issue I had to work out from sheer ignorance was milling absolutely straight lumber for picture frame mouldings I created. No matter how careful I cut the wood it would restabilize itself from the internal stress to accommodate the missing slice. Takes time after each slice. I think I managed over a period of time to take skin slices to minimize the movement. Time consuming. I later was visiting a wood specialist who designed, milled and assembled laminated wood propellers using a high tech adhesive. He was doing precisely the same type of wood slicing stress equilibrium I had used. He did warn his clients when they took possession of their shiny new prop that if they break it don't come back to me.

[@HobbyHardwoodAlabama]

Most production mills are designed to maximize yield and do not care about board straightness. Then they are put in a kiln and "case harden" or basically shrink wrap by drying the out fibers very fast and so put in a highly stressed state where as soon as you cut into it, the stress is released and the board will move. Typically, that's when travel saw blades get pinches, or you notice smoked edges on cuts, and stuff like that.

[@MakerBoyOldBoy]

@@HobbyHardwoodAlabama Thank you again for insider info lugs like your students would never be allowed to know about. This answers why there is forever stressed lumber which can never be relied upon.

[@perry9492]

My theory on why the sap wood moves so much is because there is a moisture gradient with the outside being dryer than the inside and that causes the top to be in tension since the wood tends to shrink more the dryer it gets. Good video as always. I would like to come and hang out up there sometime. Not afraid to help.

[@HobbyHardwoodAlabama]

Could be, and thanks for commenting!

[@SmokyMountainOutpost]

Good information. I’ve milled a lot of logs to build this homestead and seen that over and over. Learning quite a lot and appreciate your time and effort. Richard

[@HobbyHardwoodAlabama]

Thanks! I figure most folks who run sawmills are pretty sharp and like to know how do to better, but much of what is out there just doesn't explain the reason stuff happens. That's what I try to do a little different on my channel, provide some of the engineering behind the "Why" and most times it's a lot different than what people commonly think, or were led to believe. I was watching one of your recent videos with the washboard on one of the cuts, and you got lots of comments to "just saw faster and it will go away." That is true to an extent, but washboard is caused by a very specific set of circumstances causing and resonance or "band bounce", and yes, sawing faster sometimes loads the band and put more force on it and dampens the vibrations, but the reality that's like someone having unbalanced tires on their truck and the garage mechanic just telling them to "drive faster until it hopefully smooths down." I'll be doing a video on it sometime soon, and I appreciate your mentions.

[@SmokyMountainOutpost]

@@HobbyHardwoodAlabama we will be looking for it. No need for reply just wanted to say thanks again.

[@jesseking2368]

Very helpful pair of videos. Thank you!

[@HobbyHardwoodAlabama]

Glad it was helpful!

[@Sawbucs]

Now that you made the comment, would be well worth it, for you to explain how to take out stress in the drying process.

[@HobbyHardwoodAlabama]

That would take quite a few videos!

[@Sawbucs]

@HobbyHardwoodAlabama I watch as many sawmill videos from every source. Yours are by far the most informative. I've recently went back and watched your videos as far back as 2 years. I would think it worth it. Buts that's up to you if you want to put in the effort.

[@gregwaters944]

Great example of wood movement, never heard of this type of movement.

[@HobbyHardwoodAlabama]

Many thanks!

[@deniscarter6613]

Thanks Professor another great video explained

[@HobbyHardwoodAlabama]

Very welcome

[@SeansWoodBarn]

Another great lesson, Professor! Thanks again for taking the time to pass along the wisdom.

[@HobbyHardwoodAlabama]

My pleasure!

[@bryanhenderson5926]

Great info and linked with the visual real time milling it is very understandable. Doc.

[@HobbyHardwoodAlabama]

Thanks! It's hard to argue with real video! You know who I'm talking about.

[@bryanhenderson5926]

@@HobbyHardwoodAlabama yup

[@customsawyer2526]

Great video. I'm going to have to call you and talk to Chip later today.

[@HobbyHardwoodAlabama]

Wait til you see my next video about my loose nuts!

[@kevincasey7931]

You answered another question I've wondered about perfectly on last few cuts. Another question? Do you edge the rest of sapwood off before kiln drying or after. Ty much

[@HobbyHardwoodAlabama]

Preferably before drying for the high grade lumber to increase its value and "flatness" not so much for low grade, because I need to keep the yield up on low grade because it's worth less.

[@karlscaife6970]

Great job,thank you

[@HobbyHardwoodAlabama]

Thanks for watching!

[@liquidrockaquatics3900]

My uncle told me years ago when my grandfather made walnut clocks from cookies that he used to split off the sapwood carefully and leave the heartwood, but I don’t know if they wrapped them up or what after that

[@HobbyHardwoodAlabama]

Sapwood is just a problem in pretty much everything!

[@A..n..d..y]

Another good one.

[@HobbyHardwoodAlabama]

Thanks again!

[@Aaron-sl9lu]

Thank you, what species are less of a concern for sapwood pull?

[@HobbyHardwoodAlabama]

Typically less dense species with less extractives and stress.

[@johnwoody4905]

Good video and job really nice walnut I have 2 pine 2by 4's that are a total mess everything else is better than lowes..take care, be safe and well.

[@HobbyHardwoodAlabama]

Thanks 👍

[@bryansmith9327]

I have noticed that in all 3 videos you have done about stress that you are flat sawing. How much of a difference and what is the procedure to follow if you are quarter sawing the wood?

[@HobbyHardwoodAlabama]

You are right on, quartersawing intentionally puts the stress in the slip or curve direction and usually results in boards not stressed in the face or bow directions. So by its sawing pattern, the boards will dry much flatter than face sawn, unless stress is identified before hand and taken into account.

[@wernerberry7800]

Thanks so much for another great video Robert! You're a great teacher!

[@HobbyHardwoodAlabama]

I appreciate that!

[@randyschrock4738]

How are you able to run you're hydraulic s on both ends of your mill?

[@HobbyHardwoodAlabama]

Great observation! This mill was designed for that, but if you have a WM mill with a single contact strip so the hydros only work on one end, then you can easily install a second contact strip on the other end, run a connecting wire between them, and you will be able to do run hydros from either end.

[@theBamaJammer617]

Professor, maybe you should go ahead and give yourself the title of Doctor! That sounds more impressive! Another good video. Great outhouse analogy!

[@HobbyHardwoodAlabama]

Nah, I think that Doctors are for setting broken bones and Professors are for teaching, but I appreciate it!

[@falfas55bgas]

side wood aka jacket boards :)) Brad ...So when you say you've got the cant' to 6", is it actually 6" or is it 6.5 or 7"? What I'm getting at is, do you need to end up with 6" after drying? Or 6" after drying and straight lining one side? Or is it less than 6" at that point?

[@HobbyHardwoodAlabama]

By NHLA rules, the 6" is only required off the mill, and it can be crooked. However, I like to ove rcut the cant based on how much movement I'm seeing real time and maybe adjust to 6.5" or sometimes 7" and try to get them to clean up to at least 6" wide at a minimum when they come out of the kiln. I do lose a little on edge drop doing the SLR cleanup to bring the boards down to 6" wide but I make that up with them being straight and S4S. So I anticipate the edge drop when I'm sizing the cant to predict where to cut it to increase the value of the final dried board.

[@douglassiemens4245]

The amount of knowledge you impart could be overwhelming, if you presented it like the engineer you are. Thanks for teaching in easy to understand Southern.😂

[@HobbyHardwoodAlabama]

I like this comment! Thanks!

[@liquidrockaquatics3900]

My wife said you’re the only man that knows what six inches looks like 😂😂😂

[@HobbyHardwoodAlabama]

Because I use a measuring tape!