Progressing along on my kiln chamber build. Super-insulated slab is down, epoxy on concrete cured. So, let the framing begin!
My chamber is 22' long and I intend to load it from the side (not end). Thus, I need two 10' doors.
Would appreciate some wisdom from those who've gone before me:
1. Other than Nyle's plans for construction/insulation, and tips on hinges and gaskets...that last?
2. Since I need a 21' clear span on loading side, and tips for what to use to frame/span that far? I have some oak that I could saw into some silly-sized beams, perhaps an LVL, or man-up for a steel I beam. Again, I know all will work at some degree, but looking for some words of wisdom from those who've walked the path ahead of me! :D
Thanks. Will post some pix along the way.
Parallel chord trusses are another option. Is the header supporting anything (are the doors swinging on the side posts), just supporting the doors (track), or is it supporting some section of roof and doors? Need more info, like a sketch, or you need to determine load and allowable deflection.
Just a 10x22 box (shed) with the two 10' doors along the front, attached to the corners. Design is per Nyle's instructions, but they do not mention the clear-span details. I'll make a sketch if it helps.
Thx
With a box kiln it's all about the stability of the doors to maintain the door seals, assuming as Don mentions that the door header isn't load bearing which I built mine so it wasn't. Ready made trusses would be fast for framing.
If I was going to build what you are doing, I would go out of the box a little and build the opening for the doors as well as the door frames out of welded steel or aluminum and use the weld on security gate hinges with grease fittings. I'd make it a premade structure welded flat on the ground, corner braced and then attach it to the wooden building as a big door unit. It would be difficult but would never sag or degrade with some proper paint. I've got the setup on our security gate and it's been working for years with an 18 foot swing gate. With big doors the issue is door jamb strength, hinge strength, and door stability, holding the doors out in space through all the thermal cycles. The other key whether built from wood or steel is to build the doors as light as possible with wood or light and stiff with steel. The less they weigh the less they will sag.
It will be easy to build something that will work for a short term me, much more problematic to build one that will last for a decade.
On the clear span you could always put a temporary adjustable post in the middle and take it out when loading and uloading.
When in place it could help seal the doors in the center
Just my 2 cents
I think I would build a flitch beam if you can get a piece of steel that long. Say a piece 12" wide by 1/2" thick and sandwich it between two 2x12s.
I built parallel chord trusses for my 20 foot openings. Thus far (2 years) it's worked well.
The chord was around 4' tall.
I'm guessing about a foot of overhang on the roof so 6' of roof x 21' bearing on the header 126sf x whatever your snow+ material load is, probably in the neighborhood of a couple of tons up top. The trouble I see is that 6" end post trying to restrain racking from the 10' door hanging from it. That calls for a welded moment resisting frame, a steel post welded to a steel header or a large steel L bracket firmly connecting that joint. If it were a flitch plate header you could make the post the same way and weld the connection between the post and header plates. Flitch plates are not the most efficient use of steel though, the same weight in an I shape is stronger and stiffer. Steel parallel chord and steel post might be worth exploring. Steel fabricating plays into that efficiency cost equation too though.
Might could use door mounted castor wheels mounted to the free ends of the doors to roll on the concrete apron when they are opened, and to support them when they are closed.
What kinda monster have I created!? :o ;D
I like Yellow's idea of steel frame, but I don't have any idea what size it would take for a 20' span.
What if I were to do a "flitch beam" with a LAM and steel for the long span, then do as Yellow suggests and build a welded steel frame to insert into the opening, much like a commercial metal door.
There's a metal fab shop about 1 mile from me that does custom work. I could get them to build whatever I want (and can afford) I suppose.
Anyone have any pix/plans/sketches as food for thought?
Thx
ps. Would a 3.5 x 1.5 x 1/4" inch steel box tubing frame works a frame, ok to span? Since I'm planning 2x4 construction, per Nyle's plans, it would be mighty convenient. Steel costs looks like about $500. Could do the doors in aluminum to save weight, at a cost of about $1200-1300 materials.
I like the idea of Scott's truss. A steel truss with steel posts, might be able to simply span it with pan deck from that header to the back wall without further framing... the steel shop should be able to design and quote any or all of that.
Not sure if you have a metal building contractor nearby, but you might look at a pair of "C" or "Z" purlins sandwiched to make a beam. I used two 12 ga 8 inch "Z" purlins boxed with 2x8's between to form a box beam for my solar kiln to frame the doorway. Pics are in my gallery. The steel purlins were left over from a steel frame building that was engineered for NW PA, 10 lb dead load and 50 lb live load over a 25 ft span on 5 ft spacing, so spanning a 20 foot opening was easy. It was a few years ago that I bought them, but I think they were about a dollar a foot surplus.
Joe
If the peak of the kiln roof is centered over the door then the door header won't be load bearing, and a simple gable truss can be used to support the roof over the front door opening. Simple wooden 2x4 trusses can free span 32 feet with no problem.
The door frame and supports would be independent of the trusses.
The main load on the door frame will be the verticals where the hinges attach, which need to be stabilized to prevent the door from sagging.
Also, since the door seals by Nyle are face seals, the door jambs need to be wider than the doors so that the seals can be attached to impact the inside door skin. For example, if the doors were 2x4 thick, the door frame would need to be made from 2x6 stock.
Just curious - why did you give up on the container kiln plan?
Quote from: Southside logger on April 24, 2018, 11:43:28 PMJust curious - why did you give up on the container kiln plan?
Two primary reasons were space and aesthetic. I need to load from the long side, plus since we want to make our buildings all look pretty (part of the overall design), decided to do traditional. PLUS, when I grow weary, it will make a MIGHTY nice man-cave building! :D
Perhaps a visit to several local farms with barns, especially old barns, will give you some useful ideas. They do make hinges for large doors.
For gaskets, you could use old fire hose that looks like fabric. Very effective. The local fire department will appreciate the new hose that you bought for them to replace their old hose.
One issue, with using metal frames and doors with large spans in a kiln, is that when the kiln heats up, the metal expands, while the rest of the wall, if masonry or wood, does not. This creates cracks, as something has to give when the door frame expands.
You could also make your door frames out of heavy gauge metal framing.
3 5/8" it can be welded together and made very strong and can be purchased very reasonable.
I have seen some things made with it.
Yea - the big metal box is ugly, but I am going to wrap it with some board and batten and frame in a couple of old windows that I have so from 20' away it will look like a building.
smiley_thumbsup
Great stuff! Yellow, do you have a pic of your building you could share?
I'd like to see your front, non-load-bearing wall!
Thanks.
The problem with either is really that unbraced portal frame. If you could run out to say 24' and have a 4' solid wall section that houses a tool or equipment room at one end that would go a long ways towards bracing the opening. A bracing wall at both ends even better.
This is another way to build a braced opening with narrow sidewall sections;
http://www.anthonyforest.com/assets/pdf/apa/glulam/Tech_Topics_A_Portal_Frame.pdf (http://www.anthonyforest.com/assets/pdf/apa/glulam/Tech_Topics_A_Portal_Frame.pdf)
One of mine has an opening that size. I used a flitch beam comprising two 12x2's and 1/4" corten plate. Its way overkill... after the kiln falls over i think ill use it for a bridge girder.
My door is built on 3" aluminium RHS frame with a fair bit of cross bracing for strength without excessive weight, ½"marine ply skins, foam filled. Due to a breakdown of the other unit he kiln was commissioned before i got to hinge the door (plan A had big hinges one side and a support wheel for the far end. The single big door rather than two smaller ones was to get a better seal) so I just lifted the door into place with the forklift and cranked her up.
2 years later I still lift the door into place with a forklift: It's not much slower then swinging doors would be without the footprint of a swinging door, it seals like a bottle, and if it aint broke dont fix it.
Honestly I'd talk to some coldroom installation guys - they can probably do a nice lightweight SIP panel door with a good seal for half the price of building your own and you'll get a better job.
I have a couple pics.
With the gable directly over the door, it is a free span structure, non load bearing. I constructed the beefy doorframe header not for the roof strength, but as a top brace and anchor for the top end of the side door jams, which is where the hinges attach to the building. It must be very strong or the weight of the cantilevered doors will cause sagging. I put a half a dozen hinges on each door, and it still has some give. The doors are constructed as lightweight as possible, with the foam insulation, and are stiffened using glue and screws and plywood. I screwed the sill into the concrete.
(https://forestryforum.com/gallery/albums/userpics/21488/Kiln.JPG?easyrotate_cache=1333940649)
Notice the face seals on the doors on the door frame, and matching foam on the doors for them to seal.
(https://forestryforum.com/gallery/albums/userpics/21488/IMG_0207.JPG?easyrotate_cache=1379380486)
Quote from: Don P on April 24, 2018, 05:58:42 PM
I like the idea of Scott's truss. A steel truss with steel posts, might be able to simply span it with pan deck from that header to the back wall without further framing... the steel shop should be able to design and quote any or all of that.
Here is how mine is designed.
The bottom is comprised of three 2x12's sandwiched together (and glued). The parallel chord truss above is glued with construction adhesive and screwed to the 2x12's. It is a 20' span.
Not shown in the photo is the 1/2" plywood that was attached in full sheets covering the 2x12's and truss. It too was glued well and nailed close. For that matter, all of the exterior plywood was glued and nailed. I did this in order minimize racking in all directions and to add a lot of shear strength.
Finally, on the inside the truss was filled with closed cell spray foam, as was the rest of the kiln walls and floor.
No issues with sagging at all.
On a side note, the kiln is designed for 2000 bd ft of 4/4 oak in two stacks side by side 4' deep, 8.5" wide and stacked 30 layers high with 3/4" stickers 18" on center.
(https://forestryforum.com/gallery/albums/userpics/13296/Door_header_C.jpg?easyrotate_cache=1524863818)
Quote from: scsmith42 on April 27, 2018, 05:25:38 PMHere is how mine is designed. The bottom is comprised of three 2x12's sandwiched together (and glued). The parallel chord truss above is glued with construction adhesive and screwed to the 2x12's. It is a 20' span
This is awesome and
very helpful! Thanks much! That would seem to be a design that would work well for me and and aesthetic that I can get past the War Dept.
A few questions, if I may:
- Are the 2x12 headers all single-board spans? (the pic looks like the front one is two pieces)?
- Is the chord truss engineered design (is there a spec for it) or did you just make it to what you thought was right?
- The sides are of concern as elaborated above. Can you outline that a little too? I'm assuming that it's more 2x12's stacked and glued?
- What is your front opening height and how high is the total structure in the front?
Thanks for your efforts and picture posting!
I think this design with Yellow's idea of a metal door frame is what I'll do.
I would go with aluminum door frames, no rust and light weight.
Full opening fold back hinges so if you hang an end of a pallet of wood loading the kiln, (you will eventaully) the doors are opened completely out of the way and you will only scuff the door opening and rip the seal off that, not the doors. Not that I've ever done it, a couple times.
Remember that if you are going to drive your skidsteer in through the door you can't cant have a raised wooden door threshold or it will get torn up in a hurry. So the bottom door seal will be against concrete, or a garage door type floor seal on the concrete to meet the bottom door seal.
Here's a picture of a Kiln Direct one, I used some of these ideas for mine, many years ago.
Notice all the hinges, face seals of both the doors and the door frame, lots of cam lock clamps on the door frame top to keep the doors pressed against the seals.
(https://forestryforum.com/gallery/albums/userpics/21488/TTF-4150_front_view1.jpg?easyrotate_cache=1422792948)
Quote from: PA_Walnut on April 28, 2018, 06:51:36 AM
Quote from: scsmith42 on April 27, 2018, 05:25:38 PMHere is how mine is designed. The bottom is comprised of three 2x12's sandwiched together (and glued). The parallel chord truss above is glued with construction adhesive and screwed to the 2x12's. It is a 20' span
This is awesome and very helpful! Thanks much! That would seem to be a design that would work well for me and and aesthetic that I can get past the War Dept.
A few questions, if I may:
- Are the 2x12 headers all single-board spans? (the pic looks like the front one is two pieces)?
- Is the chord truss engineered design (is there a spec for it) or did you just make it to what you thought was right?
- The sides are of concern as elaborated above. Can you outline that a little too? I'm assuming that it's more 2x12's stacked and glued?
- What is your front opening height and how high is the total structure in the front?
Thanks for your efforts and picture posting!
I think this design with Yellow's idea of a metal door frame is what I'll do.
The 2x12's were 16 footers so there is a spice in each layer (offset across all three layers).
I swagged the truss design. One thing we messed up was that my guys installed the truss upside down on the header. The diagonal members should be pointed up and towards the center. It was already glued and screwed when I checked on them, but with the exterior plywood glued on it has not budged at all.
I'm not sure what you're asking about the sides. The corner posts are multiple stacked 2x6's with plywood glued and nailed on the outside of all walls.
Door opening is approximately 8' tall. Overall height on the door side is about 14'. I designed it this way in order to allow me to fork our standard kiln stacks into it (the standard VT design requires 5' deep stacks in order to fill to capacity, but my Nyle carts are based upon 4' stack depth).
Basically I started with Gene's VT design, narrowed the depth by a foot and increased the height at the bottom by 3' in order to accommodate my standard kiln stacks. I also widened it up.
IMO a metal structure would not require the extent of material that the wood one does. Aluminum frames with foam infill for the doors would be a great way to go (as per Robert's recommendation).
Thanks once more for the elaboration on your design. I have the slab painted, so need to start building. I used Polycuramine, (Rustoleum's Rock Solid) which is alleged to be 20x more durable than epoxy.
Been a bit distracted by just purchasing a LARGE load of walnut logs, planting 150 fir, spruce and white pine trees, seeding the hill with mega-pounds of clover for the bees, and last but not least, installing the new V3 debarked on my 40Wide, so that it reaches in far enough to debark smaller logs too. Thanks WoodMizer for the gratis upgrade to making this right.
Excuses don't dry wood though, so need to bust-a-move! :D
Pix of Rock solid floor coating. Time to frame. (had J-bolts ready to place during concrete work, but got to it too late...concrete was too setup, so will drill and anchor.) :'(
(https://forestryforum.com/gallery/albums/userpics/46676/IMG_0120~0.JPG?easyrotate_cache=1524997765)
(https://forestryforum.com/gallery/albums/userpics/46676/IMG_0121~0.JPG?easyrotate_cache=1524997763)
Another one that might help with header design. You'll need to register but they don't spam. Go to apawood.org and search for z416 "Nailed structural-use panel and lumber beams". I would use full height 6x6 solid posts as part of the end assembly, using the header ply to brace the posts from the deep beam as well as possible.
A little construction geek stuff. The concrete and inspection folks prohibit "wet stabbing" anchor bolts into concrete. What usually happens is the bolt pushes the aggregate down and just cream flows up around and over the hook providing little strength. They want to see us hang them from the formwork prior to the pour and pour around them nowadays. Actually that kind of forces us to get them in the right line and to the correct depth but it does take more time.
I would love to know how well that floor holds up. Did you do any grinding or acid washing for surface prep?
Quote from: Crusarius on May 01, 2018, 12:40:52 PMI would love to know how well that floor holds up. Did you do any grinding or acid washing for surface prep?
I'll report back at a later date. I did not etch, since it was a new pour. I left the surface a little rough to help with adhesion. I put the little specs on there so it would look better once scratched-up, etc.
It's also cool, so when I retire from lumber, I can make it into a man-cave, complete with bourbon tap. 8)
I have an aluminum door set and frame being manufactured too. Gonna cost more per sq ft than my house! :o
You might consider getting the door seals from Nyle ASAP. Then get them to the metal guy and have him mount it.
Well, 15 months later...kiln build is almost done and ready to build and hang doors. My metal guy ghosted me, so going with wood for now: light as possible build, wood frame, 5" (two layers) of polyiso in center, and some VERY light skin to cover, either in metal or something like 1/4" pine B&B to match rest of build.
Of course, lot of seals and cam-locks to hold them tight.
Anyone have info/links for really great super-duty hinges? The sides have solid oak 8x8's to bolt or lag to, so I don't see issues there.
Thanks in advance.
p.s. I'll post some pix asap.
P.A. Walnut, when you get that all done come up here and build me one!
PA tractor supply has barrel hinges. they work very well for very heavy doors. I had a shed that had a 15' opening and two very large doors. they worked great.
Here is a link for one half of the hinge.
https://www.tractorsupply.com/tsc/product/national-hardware-n131-409-298bc-pintle-zinc-plated (https://www.tractorsupply.com/tsc/product/national-hardware-n131-409-298bc-pintle-zinc-plated)
here is the other half.
https://www.amazon.com/National-Hardware-N131-060-294BC-plated/dp/B000BQT1JE/ref=asc_df_B000BQT1JE/?tag=hyprod-20&linkCode=df0&hvadid=168556243666&hvpos=1o2&hvnetw=g&hvrand=17810590222632361197&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9005646&hvtargid=aud-799727667774:pla-305765441651&psc=1 (https://www.amazon.com/National-Hardware-N131-060-294BC-plated/dp/B000BQT1JE/ref=asc_df_B000BQT1JE/?tag=hyprod-20&linkCode=df0&hvadid=168556243666&hvpos=1o2&hvnetw=g&hvrand=17810590222632361197&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9005646&hvtargid=aud-799727667774:pla-305765441651&psc=1)
I have had very good luck with them. You can get them both at tractor supply but their website is less than stellar when searching.
We just used the largest strap hinges that would fit and struc screws. The doors are ~8x8, 1/2" ply 2x framing with 2 layers of foam. I've been thinking about trying layflat hose wrapped around the doors and pumping it up to form a seal.
Another large kiln opening in need of a door. As you can see in pic my kiln is in the back of a building. I am thinking a bifold, airplane hanger type door to save space in front of the kiln. Opening is 24' any ideas on how to make light door that will be rigid as it goes from verticle to horizontal?
My header is a 12" double LVL.
(https://forestryforum.com/gallery/albums/userpics/34928/20181102_191557~0.jpg?easyrotate_cache=1572870790)
Quote from: logbyr on November 04, 2019, 07:34:54 AM
Another large kiln opening in need of a door. As you can see in pic my kiln is in the back of a building. I am thinking a bifold, airplane hanger type door to save space in front of the kiln. Opening is 24' any ideas on how to make light door that will be rigid as it goes from verticle to horizontal?
My header is a 12" double LVL.
(https://forestryforum.com/gallery/albums/userpics/34928/20181102_191557~0.jpg?easyrotate_cache=1572870790)
Since you're indoors on a slab, a roller wheel mounted outside the doors at the bottom of the doors will relieve a lot of stress from the door hinges.
However a horizontal bi-fold door wouldn't be a bad option either. Probably get a better seal on it.
Something to keep in mind if your kiln is on a pad larger than the chamber is that the concrete will suck the heat out of the kiln. I recommend an insulated floor on top of the pad.
Thx for the warning. I have pex tubes in the floor and intended on firing up the zones under the kiln and in the office behind the kiln this winter. Next summer when I've realized some cash flow I would like to insulate the main building and keep the whole thing warm next winter.
I had not thought of heat creep out of the zones under the kiln. May have to bite bullet and just deal with it this winter. Most of my wood is sub 20% moisture so it should be a short kiln time. I think 3 or four fills and I'll have enough dry wood to sell untill warmer weather kicks in
When I used to build houses, came up with a way to build a 16' garage door header that did not sag. Used 2- 2x12 's at the bottom of the header, and 2- 2x4's at the top, just under the top plate, and would frame the wall with the bottom 2x12 and bottom 2x4 nailed in, with blocking under the headers so they would stay straight, then rip 2 sheets of plywood that went from the top of the 2x4 to the bottom of the 2x12, use glue before laying down, then lay the corresponding 2x12 and 2x4 on top of the plywood, using glue as well, then nail through the boards with 3 1/2" nails, stand the wall and then put flat 2x4's on 16" centers on both sides of the ply between the headers. This way you can have about a 3' wide header over your opening which will not sag. Should work for a solar kiln as well.
If possible, for this winter, you could lay some rigid insulation board about two feet or three feet wide all around the outside of the kiln on the floor to minimize heat loss. Concrete does conduct heat well, so floor insulation inside the kiln is indeed appropriate in the future.
For a kiln that has its own slab, it is suggested that a trench outside the edge of the floor be dug about two feet deep and then vertical board insulation is placed around the entire foundation and edges of the floor. And then fill the trench back up. Also, any concrete above the ground needs to be insulated on the exterior.
Ready to get doors up today. Build them out of hemlock for frame. Will see if pintle and strap hinges will hold it.
As for floor insulation, I'm good. Put down mono block forms and 2" polyiso under it. Slab is well insulated.
(https://forestryforum.com/gallery/albums/userpics/46676/IMG_9984.JPG?easyrotate_cache=1523958964)
(https://forestryforum.com/gallery/albums/userpics/46676/IMG_9991.JPG?easyrotate_cache=1523958878)
I have never seen those forms before. I like those.
Quote from: Crusarius on November 26, 2019, 07:25:09 AMI have never seen those forms before. I like those.
Yes, they are just brilliant! Makes pouring easier and great insulation. WIN:WIN!
So you just did you gravel base set the forms put the foam in the bottom and pour? I love it. What kind of cost are they?
Yes, gravel base, set the forms, use 2x8's to hold them together, stake them down, fill center will more gravel (to make a monolithic pour--thicker at the perimeter).
They are awesome, fast and easy.
I have NO affiliation with them at all, just pleased customer. Monoslab EZ Forms. Mine were about $1k.
I'm going to upload more pix of my entire build...been a labor of love. (for a long-term use)!
Awesome. Thanks for the info.