6 ms·

I can't think of any reason to acclimatize them this way instead of kiln drying/vaporizing them (depending) to roughly the right moisture content and waiting fo

I can't think of any reason to acclimatize them this way instead of kiln drying/vaporizing them (depending) to roughly the right moisture content and waiting for 1% change (instead of kiln drying them to 0, or waiting forever for completely green wood) There are studies going back to the 70's by the forestry service (and others) showing there is no change in mechanical properties of pine/fir from these drying schedules. (This is not true of a lot of hardwoods, but is true of these softwoods) Waiting years seems like a pointless waste of time.

maxerickson 8y ago
The stockpile is "tiny" so I guess it doesn't really matter unless they are running low on material.
- komali2 8y ago
  Doesn't make sense to put the capital forward for a kiln if they don't need it!
  - DannyBee 8y ago
    A solar kiln costs just about nothing (less than a thousand bucks, easy)
    - shub 8y ago
      Still more time and money than stacking boards in the back of the shop.
jeromenerf 8y ago
> Waiting years seems like a pointless waste of time. They have a long running stock. They are not wasting time anymore, they may be wasting storage though. Something could be said about the stock fire risk exposure, but hey, they are the firemen after all.
exDM69 8y ago
The material they show in the article is massive. Thick, long and heavy. Even if there are kilns big enough, the wood would no longer be straight after a fast kiln drying. A 50' 3x3" board would be twisted and bowed so much that the ladder would be a spiral staircase. It doesn't matter for 20' 2x4 destined for a construction site. Even if the wood was kiln dried, it would still have to acclimatizate for months or years before it would be at a stable 13% humidity of San Francisco.
- DannyBee 8y ago
  "The material they show in the article is massive. Thick, long and heavy. Even if there are kilns big enough, the wood would no longer be straight after a fast kiln drying." This is not true, depending on timeline. It's true of the production rate kilns, and as you say, it doesn't matter for construction lumber, which is why they do it. But assuming 3+ years to dry your 3x3" board, even doing it in a kiln at a 6 month rate (or whatever) would be a vast improvement, and would basically not bow or check. Again, there is actually a vast amount of research on drying schedules vs defects and how to optimize for whatever you want for a given wood species. As for kiln size, again, solar kilns are quite trivial to build for basically any size or shape, and can easily be temperature controlled for something like this. (and they could easily build a kiln in the space they have shown in that article) To whit: I've built a solar kiln in maryland for 30+ ft boards before, and cost of materials was < $1000. (I used to buy lumber from a guy who was responsible for handling downed trees for some cities in northern virginia, and he used to saw and sell the lumber. He did the nail removal, etc) "Even if the wood was kiln dried, it would still have to acclimatizate for months or years before it would be at a stable 13% humidity of San Francisco." Why? You can just stop drying it at 13% (instead of the 7-8% that is normal).
  - coryfklein 8y ago
    These ladders last decades so presumably most of the shop work is in maintaining existing ladders, not in pumping out lots of new ones. It would be a waste of time and money to kiln fire the wood for 6 months when you can just order it 1-2 years in advance and leave it in the corner to accomplish the same purpose.
padobson 8y ago
I'm not sure how many degrees of separation this knowledge is from programming, but it's got to be one of the highest values I've ever seen on HN. Bravo.
- DannyBee 8y ago
  I've been woodworking heavily for 20+ years, and actually have run 3-4 kilns. Just FYI.
- blattimwind 8y ago
  FYI hobbies and dayjobs are not legally mandated to be correlated.
- tptacek 8y ago
  It's funny how well this kind of lowbrow snark works here until exactly the moment it totally doesn't.
Aloha 8y ago
It probably is a waste of time, unless time is not a critical factor. If time is not a critical factor, it'd be a premature optimization to bother with a kiln.
pm24601 8y ago
> "I can't think of any reason to acclimatize them this way instead of" .... I bet the expert woodmakers doing this job have very good reasons. Reasons that you haven't thought of.. Seriously, these people are experts. They probably know their job, really, really well.
- DannyBee 8y ago
  "I bet the expert woodmakers doing this job have very good reasons. Reasons that you haven't thought of.. Seriously, these people are experts. They probably know their job, really, really well." This is just a random appeal to authority. If you would like to be constructive, please be constructive. First, there is one person doing this. Or was. It was Jerry Lee, who recently retired. He did it for 30 years. In fact, for giggles, i reached out this morning, and Jerry Lee says he is not an expert by any means in any of this. He was just a pattern maker who thought he could be helpful. He had no particular expertise in this when he started, and he would argue he is in fact, not an expert. When I asked, he said they just didn't need to do it faster. So it turns out no, they aren't magical experts trained in the artisanal art of ladder making with information passed down from the ages, and no, there are no magical reasons that only the wood cognoscenti have thought of. Sorry. They just use the forestry handbook data and info like everyone else!
  - donarb 8y ago
    Isn't a forestry handbook a "random appeal to authority"?
    - tptacek 8y ago
      At the point where one of us literally called up the dude who was doing the work and asked, can we dispense with the message board rhetorical kung-fu and just have the rest of the conversation? Thanks.
    - DannyBee 8y ago
      Actually, no, it's a very very very well thought out resource that has references to where the research comes from and citations for it's data. It may come as a surprise, but this really is engineering. People have been studying wood as an engineering material for a very long time, and there are a large number of published studies on pretty much anything you can think of from drying rates to density to you name it. Take a look at https://www.fpl.fs.fed.us/products/publications/several_pubs.php?grouping_id=100&header_id=p https://www.fpl.fs.fed.us/products/publications/several_pubs...

maxerickson 8y ago

The stockpile is "tiny" so I guess it doesn't really matter unless they are running low on material.

komali2 8y ago
Doesn't make sense to put the capital forward for a kiln if they don't need it!
- DannyBee 8y ago
  A solar kiln costs just about nothing (less than a thousand bucks, easy)
  - shub 8y ago
    Still more time and money than stacking boards in the back of the shop.

jeromenerf 8y ago

> Waiting years seems like a pointless waste of time. They have a long running stock. They are not wasting time anymore, they may be wasting storage though. Something could be said about the stock fire risk exposure, but hey, they are the firemen after all.

exDM69 8y ago

The material they show in the article is massive. Thick, long and heavy. Even if there are kilns big enough, the wood would no longer be straight after a fast kiln drying. A 50' 3x3" board would be twisted and bowed so much that the ladder would be a spiral staircase. It doesn't matter for 20' 2x4 destined for a construction site. Even if the wood was kiln dried, it would still have to acclimatizate for months or years before it would be at a stable 13% humidity of San Francisco.

DannyBee 8y ago
"The material they show in the article is massive. Thick, long and heavy. Even if there are kilns big enough, the wood would no longer be straight after a fast kiln drying." This is not true, depending on timeline. It's true of the production rate kilns, and as you say, it doesn't matter for construction lumber, which is why they do it. But assuming 3+ years to dry your 3x3" board, even doing it in a kiln at a 6 month rate (or whatever) would be a vast improvement, and would basically not bow or check. Again, there is actually a vast amount of research on drying schedules vs defects and how to optimize for whatever you want for a given wood species. As for kiln size, again, solar kilns are quite trivial to build for basically any size or shape, and can easily be temperature controlled for something like this. (and they could easily build a kiln in the space they have shown in that article) To whit: I've built a solar kiln in maryland for 30+ ft boards before, and cost of materials was < $1000. (I used to buy lumber from a guy who was responsible for handling downed trees for some cities in northern virginia, and he used to saw and sell the lumber. He did the nail removal, etc) "Even if the wood was kiln dried, it would still have to acclimatizate for months or years before it would be at a stable 13% humidity of San Francisco." Why? You can just stop drying it at 13% (instead of the 7-8% that is normal).
- coryfklein 8y ago
  These ladders last decades so presumably most of the shop work is in maintaining existing ladders, not in pumping out lots of new ones. It would be a waste of time and money to kiln fire the wood for 6 months when you can just order it 1-2 years in advance and leave it in the corner to accomplish the same purpose.

padobson 8y ago

I'm not sure how many degrees of separation this knowledge is from programming, but it's got to be one of the highest values I've ever seen on HN. Bravo.

DannyBee 8y ago
I've been woodworking heavily for 20+ years, and actually have run 3-4 kilns. Just FYI.
blattimwind 8y ago
FYI hobbies and dayjobs are not legally mandated to be correlated.
tptacek 8y ago
It's funny how well this kind of lowbrow snark works here until exactly the moment it totally doesn't.

Aloha 8y ago

It probably is a waste of time, unless time is not a critical factor. If time is not a critical factor, it'd be a premature optimization to bother with a kiln.

pm24601 8y ago

> "I can't think of any reason to acclimatize them this way instead of" .... I bet the expert woodmakers doing this job have very good reasons. Reasons that you haven't thought of.. Seriously, these people are experts. They probably know their job, really, really well.

DannyBee 8y ago
"I bet the expert woodmakers doing this job have very good reasons. Reasons that you haven't thought of.. Seriously, these people are experts. They probably know their job, really, really well." This is just a random appeal to authority. If you would like to be constructive, please be constructive. First, there is one person doing this. Or was. It was Jerry Lee, who recently retired. He did it for 30 years. In fact, for giggles, i reached out this morning, and Jerry Lee says he is not an expert by any means in any of this. He was just a pattern maker who thought he could be helpful. He had no particular expertise in this when he started, and he would argue he is in fact, not an expert. When I asked, he said they just didn't need to do it faster. So it turns out no, they aren't magical experts trained in the artisanal art of ladder making with information passed down from the ages, and no, there are no magical reasons that only the wood cognoscenti have thought of. Sorry. They just use the forestry handbook data and info like everyone else!
- donarb 8y ago
  Isn't a forestry handbook a "random appeal to authority"?
  - tptacek 8y ago
    At the point where one of us literally called up the dude who was doing the work and asked, can we dispense with the message board rhetorical kung-fu and just have the rest of the conversation? Thanks.
  - DannyBee 8y ago
    Actually, no, it's a very very very well thought out resource that has references to where the research comes from and citations for it's data. It may come as a surprise, but this really is engineering. People have been studying wood as an engineering material for a very long time, and there are a large number of published studies on pretty much anything you can think of from drying rates to density to you name it. Take a look at https://www.fpl.fs.fed.us/products/publications/several_pubs.php?grouping_id=100&header_id=p https://www.fpl.fs.fed.us/products/publications/several_pubs...