L200M Shipping Container Insulation/Painting Questions

[Swernicus]

I've done some searching through the forum and it's easy to see the recommendation is to use a reefer container for DH kiln chambers.  I wish I could go that route but I have a 20' standard container on site already and my plan is to convert that to a L200 chamber.  I've read the various threads on related builds but I have some specific questions still about corrosion prevention and insulation..

I plan to have the interior of the chamber sprayed with closed cell foam at 2-3" thick (any recommendations on thickness would be great, is 3" necessary).  However, should I paint the interior steel surface with a rust preventative coating before insulating?  Obviously a spray foam job will do a decent job of air sealing but I'm not so confident it will entirely coat the steel interior and protect it from the extremely corrosive kiln environment.  The container is in good shape with minimal rust right now.  It is sitting on asphalt pad with no covering.

Next question is would it be a good idea to build stud walls on the interior walls and have the cavities filled with foam and trimmed back, then tack polyiso foam over the studs?  I mainly am considering this because i have seen similar kiln containers with exposed spray foam and it gets damaged, seems to degrade, and just doesn't look very sightly.  One container i have seen seemed to have the foam delaminating from the steel walls due to shrinkage it appeared.

Lastly, i plan to use a track system to load and unload, so what is the best method of insulating the floor of the chamber? My initial thoughts are to use polyiso board adhered to the ground with spaces cut out to allow the track to lay in it, with proper relief so the wheels can slide by.

I am just starting to get the wheels turning on this project as the weather here in MI finally warmed up and I can start working on this.  Maybe I should have used al that winter time to plan better... haha

[Southside]

You are asking for advice and I am going to give you the advice you don't want to hear. Sell your existing container or re purpose it and get a genuine insulated sea can. The effort and expense you put into your corten steel container will become heartbreak when it begins to dissolve before your eyes in just a few years. 

[K-Guy]

The effort and expense you put into your corten steel container will become heartbreak when it begins to dissolve before your eyes in just a few years. 

Well said!! 

[farmfromkansas]

If what I have read is correct, the L200M should be able to handle a 40' insulated shipping container, so starting with a 20' is going to cost you half the available production.

[Swernicus]

Yeah, it's sort of an opportunity cost equation.  I have the 20' one on site now, it's already there and paid for.  So yeah i can spend 2k more on spray foam or try and sell it and invest in the reefer.  The problem is the reefers are over $7500 from what i can see and that's not including freight.  I can't find one within 500 miles either. Been looking on and off for about a year.  

Finally reserved myself to outfitting the 20' i have now.  I can always upgrade later, but I dont think i can hold off not having a kiln any longer!  :D

With that being said, I understand the best option is to just ditch what i have and upgrade to the reefer, however... could you humor me with some advice on how to make this one work for now?  It's not my permanent setup but there's a huge market demand for dried lumber where I live and I am shelling out alot of cash to haul my lumber back and forth to guys who are basically running this identical set up 50 miles away.

I appreciate the feedback guys

[Southside]

I would look at stick building one then.  You are loosing so much capacity in that 20' unit and I would not give it a year before you could see the issues happening.  

[scsmith42]

I built my first kiln in 2003 using a 45' high cube shipping container and a Woodmizer 200 (Nyle 200) unit. It's been in almost constant use since then.

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]If I were building a new container kiln today from a non insulated box I would do the following with a 45' high cube container:[/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]1 - build a "bay window" so to speak on one side of the container about half-way from the entrance to the back of the container. Install the Nyle unit in the bay window area.  [/font]Then clean and paint the entire interior with an epoxy or 2 part urethane paint to preserve the metal. Over it attach plywood and apply Cool Seal.

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]2 - attach metal studs all around the outside of the kiln, and some 3/12 pitch roof trusses on top of it. [/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]3 - have the entire exterior, including the underside of the container sprayed with around 3" of close cell spray foam. [/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]4 - apply some type of exterior wood such as board and batten, etc, and put a roof on top of the trusses so that the entire foamed exterior is covered in some type of protection, save for the doors. [/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]5 - insulate the inside of the doors with foam boad, shooting for 3" of thickness. [/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]6 - install a track system inside the container consisting of 1/4" x 4" flat bar, with an inverted 1.25" angle running down one side for the kiln cart wheels to track down. I would install fan baffles and 6 fans inside the container. This is important to spread the weight from the kiln carts across the floor.[/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]This setup will allow you to stack up to 6' of lumber (in a 9'6" tall high cube container) on your kiln carts and roll them under the baffle.[/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]Nyle can provide cart plans and sell you the roller wheels.[/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]Unless you are milling a fast drying species such as pine or poplar, a 20' standard height container will only let you dry around 35% of the capacity of an L200. Frequently you can source a surplus refrigerated semi trailer that would be a better choice than a 20' steel container.[/font]

[font=system-ui, -apple-system, BlinkMacSystemFont, .SFNSText-Regular, sans-serif]Scott[/font]

[Swernicus]

Thank you for the great info!

Do you have any paint recommendations? I really am just looking to have this kiln last for about 2-3 years before I move to a bigger facility and have room for a 40ft HC reefer.

Thanks!

[K-Guy]

the L200M should be able to handle a 40' insulated shipping container

That depends on what you are drying, hardwoods or softwoods. On hardwoods it still has more capacity than a L200 can handle but a 20 can't hold enough.

[scsmith42]

Thank you for the great info!

Do you have any paint recommendations? I really am just looking to have this kiln last for about 2-3 years before I move to a bigger facility and have room for a 40ft HC reefer.

Thanks!

Personally I'd suggest building for the long term.  
When you move to a larger facility you  may want to dedicate the smaller kiln for long drying species, such as slabs, and build a larger kiln for higher volume lumber.
Re paint, any good industrial grade two part paint should work well.  I've use products that are designed for ocean based oil rigs and they are quite durable.
I'd seek out local paint suppliers to see what they have available for high humidity, caustic environments.

[Swernicus]

My L200M is going to arrive in the next week, and my effort to get an insulated container have been fruitless so I'm moving forward with the one I have.  The market for containers (insulated and standard) is pretty insane right now... to get a 40' reefer delivered it's about 8-10k depending on condition, and the few 20' ones i found at auction were very far away and would be a nightmare to coordinate moving across the country...

I was wondering if anyone had some suggestions for insulation the floor of the standard shipping container without lifting it up or tipping it.  Probably another bad idea but would it be possible to lift all the plywood on the floor and insulate the spaces between the floor beams with foam board or spray foam in those cavities?

Any suggestions are appreciated.  Excited to start building this thing!

[K-Guy]

I would recommend getting the 40' insulated container and partitioning it.

[cabindoc]

Do what I did.  Find a refer truck body in good shape.  If you want it somewhat portable, they can be moved almost as easy as a shipping container.  I paid $800 for 21'  Or 40' retired refer trailer if you don't mind it being that high off the ground.

[scsmith42]

My L200M is going to arrive in the next week, and my effort to get an insulated container have been fruitless so I'm moving forward with the one I have. 

I was wondering if anyone had some suggestions for insulation the floor of the standard shipping container without lifting it up or tipping it.  Probably another bad idea but would it be possible to lift all the plywood on the floor and insulate the spaces between the floor beams with foam board or spray foam in those cavities?

Any suggestions are appreciated.  Excited to start building this thing!

On mine the floor is not plywood, and removing it would be an incredible pain. I would personally have it lifted up by a crane and the underside sprayed with closed cell spray foam insulation.

[Southside]

The joy of having man toys!! (Personal crane)  ;D

[Swernicus]

I've been looking into what it would take to have it lifted up, or even tilted enough to get spray access to the underside... but not many options where I am and the heavy equipment i do have access to would probably lift/tilt it however I would not feel safe going underneath to spray.  

The floor in mine is marine plywood screwed down.  I plan to pull that up and replace it and also replace the fasteners with SS ones.  

While i have the floor panels up i figured i'd try and insulate underneath rather than building up insulation inside the container and robbing myself of valuable chamber space.  I have extra closed cell spray foam from my day job so the floor is a perfect place to use it.