iDRY Vacuum Kilns

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Big Slabs: Sales and handling

Started by jemmy, June 23, 2017, 10:44:34 PM

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xlogger

Has anyone put 8/4 white oak straight from the saw into their DH kiln? Say about 400 ft load. How long did it take? I'm looking into my book Nyle sent me and see where it says db 90 wb 86. I don't have any just trying to understand the setting.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

plantman

I'm no expert by any means but a few ideas come to me when I think about marketing wood. First off, because it's a product with individual character people want to see, touch, and feel it in person. That makes selling it a local endeavor or you're going to have to take your 1000 lb slab and truck it to a flea market somewhere people want natural wood. People with deep pockets are always looking for something to impress their neighbor so I think big city areas are good for high end product. If you don't want to risk much then you're probably willing to settle for less reward, meaning that you could advertise on craigslist outside of your area the fact that you have these big logs and will mill them for a price and then you let the next guy worry about whether they warp, crack, split etc.
I personally believe that if there was a big demand for slabs of wood the mills would be producing and selling them at Home Depot. Obviously , it's a small niche market. You could speculate and produce a finished product but when you're all done you will have only a limited number and then be saddled with the task of marketing them. Not only that but warehousing you're product cost money.
If you are reasonable and get those huge dollar signs out of your eyes I think producing less expensive rustic furniture for a local market might be the way to go. Just think about whether you would buy it yourself before you go producing a 500 lb picnic table.

grouch

Quote from: jemmy on July 08, 2017, 01:01:05 AM
Grouch, I thought that drying them with in a conventional kiln would do that? And from the people that I have talked with there has been one constant and that is the best way to dry thick slabs is to vacuum kiln them. I'm going to air dry them to 25-30% then send them to the vacuum kiln so that it minimizes the potential for imperfection. And a new development (after talking with another vacuum kiln owner/operator) said that he cuts red oak and gets it into the vac kiln the same day. Now, is there anything wrong with this intel? I've heard two separate things both from reputable operators, and I'm confused as to what which was one is correct. Also, is there much demand for red/white oak live edge? After our discussion one of the vac kiln owners said that he practically never gets orders for either species. I figured oak would be one of the most sought after things you could produce. Is that assumption wrong? Another question, if I am going to be vac drying them, should I cut them thinner then 3" or should I keep that thickness?

You're asking the wrong person. :) See YellowHammer's replies, for example.

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WDH

Surely a vacuum kiln will do the best job, but they are too expensive to operate on a small scale. 
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

rjwoelk

Just a rough calculation on the weight would be in the 32000 lb after slabing. 37000 lbs in the raw.  just a close figure. As a long haul driver, find a trucking company, it is a light load. may be cheeper than hauling several loads yourself.
Lt15 palax wood processor,3020 JD 7120 CIH 36x72 hay shed for workshop coop tractor with a duetz for power plant

YellowHammer

Quote from: xlogger on July 08, 2017, 08:27:41 AM
Has anyone put 8/4 white oak straight from the saw into their DH kiln? Say about 400 ft load. How long did it take? I'm looking into my book Nyle sent me and see where it says db 90 wb 86. I don't have any just trying to understand the setting.

No, I have never done it, as it would be painfully slow and inefficient.  For example, generally, 4/4 upland white oak has a maximum drying rate of about 2.5% per day.  If it's 8/4, the max rate would be cut in half, and I generally like to use 1% per day as my target for white oak, anyway.  So a green tree may have at least 50% or 60% Moisture Content.  So right off the bat, it would take about 2 months, at 1% per day, including sterilization and equalization.  Which means under optimum conditions, the kiln is tied up for 2 months.  Now consider the accuracy required to meet that schedule...if the moisture removal rate is misjudged, miscalculated or mismeasured by even a half a percent, the drying time could extend to 4 months of kiln occupancy time, which would be unacceptable to most people. Of course, if it's in error in the other direction, it's a dead load of wood. 

Consider that I try to get a load out every 7-9 days as I try to minimize kiln occupancy time for the finishing and sterilization stage.  So putting green wood, especially white oak, directly in the kiln would cost many lost loads. 

As far as the Nyle settings, they are very conservative and sometime not realistic.  They want the dry bulb at 90° which would be nearly impossible to hit and hold in the the south in the summer, where we routinely exceed that outside air temperature, so venting hot air won't work, as the air coming in is already hotter than what the schedule calls for.  So the kiln schedule is a basic suggestion, and I always figure I will make measurement and suitable adjustments after the first 24 hour cycle after I've measured my moisture loss. 
YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

xlogger

So in your answer on about putting thick oak straight to the kiln is only red oak?
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

plantman

I've never dried wood but from a common sense perspective it would seem to make sense that a wood which is permeable like red oak would dry more easily than a impermeable like white oak.

Quote from: xlogger on July 10, 2017, 05:04:16 AM
So in your answer on about putting thick oak straight to the kiln is only red oak?

WDH

While still a difficult to dry species, red oak is not as difficult to dry as white oak (one of the most difficult).  Still, I would not put a green load of any kind of 8/4 oak in my kiln because of the very slow and long drying time, tying up the kiln for a couple of months like Yellowhammer points out.  If it is air dried to 20% of less, you can dry it in 1/5 the time, and the wood is not worth enough to me to give up 5 kiln loads for 1 kiln load of oak. 
Woodmizer LT40HDD35, John Deere 2155, Kubota M5-111, Kubota L2501, Nyle L53 Dehumidification Kiln, and a passion for all things with leafs, twigs, and bark.  hamsleyhardwood.com

Ron Wenrich

I went to a hardwood dimension plant where they had predryers.  Basically it was a shed open on one side with fans pushing air through the lumber.  Most of their lumber was red oak, cherry and maple, at that time. 

I also wonder about getting surface checks in white oak.  I had some that we put on sticks and the buyer was reluctant to buy it because it got surface checks.  It was in the spring, and we had some pretty good breezes and low humidity.  He explained the surface checks came from drying the skin too quick and sometimes they don't seal back up during the kiln process.  Would you have that problem going from green straight into a kiln?
Never under estimate the power of stupid people in large groups.

plantman

I've read a lot about treating wood with antifreeze. The author of a study claimed that he treated the wobbley legs of a chair and they firmed up. He claimed that it would get rid of checks in wood. Maybe everyone doesn't want antifreeze in their wood but it would be nice to simply treat the green wood, stabilize it , and make it ready to use. The author claimed that the color change was not noticeable . Today antifreeze comes in orange as well.

Quote from: Ron Wenrich on July 10, 2017, 11:28:38 AM
I went to a hardwood dimension plant where they had predryers.  Basically it was a shed open on one side with fans pushing air through the lumber.  Most of their lumber was red oak, cherry and maple, at that time. 

I also wonder about getting surface checks in white oak.  I had some that we put on sticks and the buyer was reluctant to buy it because it got surface checks.  It was in the spring, and we had some pretty good breezes and low humidity.  He explained the surface checks came from drying the skin too quick and sometimes they don't seal back up during the kiln process.  Would you have that problem going from green straight into a kiln?

xlogger

Quote from: WDH on July 10, 2017, 07:24:55 AM
While still a difficult to dry species, red oak is not as difficult to dry as white oak (one of the most difficult).  Still, I would not put a green load of any kind of 8/4 oak in my kiln because of the very slow and long drying time, tying up the kiln for a couple of months like Yellowhammer points out.  If it is air dried to 20% of less, you can dry it in 1/5 the time, and the wood is not worth enough to me to give up 5 kiln loads for 1 kiln load of oak.
That's what I was thinking but looking at Robert's post #74 threw me off. I guess this should be under the drying topic.
Timberking 2000, Turbo slabber Mill, 584 Case, Bobcat 773, solar kiln, Nyle L-53 DH kiln

YellowHammer

Red oak can tolerate 3.8% at 4/4, half that at 8/4, which is still very slow.  More forgiving than white oak, but generally will still check if thick wood is milled in the summer. I will mill most of my oaks from Thanksgivng to Christmas to get best quality of wood and minimum kiln time.  Slow drying conditions when the wood needs it, slightly faster when the wood can tolerate it.     

Here's why, starting about page six. 
http://sbisrvntweb.uqac.ca/archivage/030108539.pdf
YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

scsmith42

When I have dried 8/4 QSWO or QSRO from green in my Nyle, it was a 3-1/2 month kiln run.  I can only do it in the winter because I'm unable to keep the temps low enough to start the load during the summer time.

It was only successful after I added a misting system into the kiln.  During the first few weeks I have to add moisture in to keep the RH% higher than with 4/4; otherwise it will surface check.

Rather than assuming a 50% reduction as thickness is increased, I have had better success reducing the drying rate by 60% per additional inch of thickness over 4/4.  Thus, starting with 3.8% for 4/4, the drying rate for 8/4 is 1.5%, and for 12/4 is .6%.  Since 8/4 QSWO is milled green at around 2-3/8", my targeted maximum daily drying rate is about 1%.

Having said all of that, the only kiln that I'll load with green 8/4 oak is a solar kiln during the fall, winter or early spring.  I have had some excellent success with that.
Peterson 10" WPF with 65' of track
Smith - Gallagher dedicated slabber
Tom's 3638D Baker band mill
and a mix of log handling heavy equipment.

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