Show us your Door Thread

[Chach]

Very nice, Ricky!

Thanks, I appreciate it.

Ricky

[Dino_Pizza]

NO WELDING on my door. I can’t weld and the last thing I need is another tool I never use in my garage, so after 12 years, my “temporary” door made of left over oven cement and board and insulation broke open. And I wanted it to be all stainless or common steel and no aluminum or zinc coatings.

New Door Ingredients:
I bought a Common Steel at 20gauge thick sheet (I have to spray paint it with high heat bbq paint to prevent rust.)
20g common steel was easily cut by HF electric sheers (yay!, this was my 1st hurdle)
I used 6 u-brackets (stainless steel of course) for the frame, on the inside to bolt-sandwich the inner and slightly bigger outer door together.
I then cut one 2” steel strip for the bottom and sides… then a 24” piece for the curved top that needed a bend at each end so they can be bolted to the sides at a small overlap.
I applied a tube of high heat food safe silicon as a bead into the inside seams of the inner door and edge, then layer in 2 layers of good oven insulation then layer a piece of oven safe silicon ( blue mat from Amazon) cut to fit so there would be a minor bit of insulation between the 6 brackets and the outer door.
Bought those bbq handles on Amazon.
Put thru-bolds in from the outer door to sandwich it together, added more silicon sealant (very little at minor gaps), spray painted again and it’s done.
OH, I put 2” peel and stick Kevlar-nomax smoker felt along the bottom and the door goes in softly but tight.
There was some steel filing, and oven arch grinding that was unavoidable but it fits great now. The 20 gauge common steel finished door feels really solid, I’m glad I didn’t go thicker or thinner.
……….
last week made pizza, then put the door on at night at 650°., it was 475° next morning and 270° on third morning. The IF gun said door was. 150-125° for the first two days. I am HAPPY .

Other hurdles: finding SS brackets (these where for barn-door 2x4 barricade and where the most expensive parts), that I had to drill with hand drill, good bits, and drilling oil. Buying 2-3 $8 to $15 SS lock washer, screw and bolt packs, and I was so nervous about bending my 2” wide edge 90° for the bottom piece and a partial bend for the curved top, but simple mallet and vise bolted to short piece of wood on my patio table was all the work bench I needed and it turned out great.

The Dorothy’s Slipper magnet is temporary until we find something unique and larger and then glue a magnet on it, Perhaps a painted Italian tile or slice of polished stone. Last pic is Lamb Shank with fresh sauce from our garden tomatoes , and a grilled octopus with Mayer lemon, zucchini, and rosemary.

[MarkJerling]

Looks good Dino! Like you, I can't weld, so I really like your solution.

[Dino_Pizza]

Thanks Mark, I have to thank this community for all the inspiration over the years to figure out ways to do things that are new to us and so unique to a WFO build.
Cheers, Dino

[david s]

Nice job. You may have gone a bit heavy with the brackets and bolts as they are highly conductive steel. The bigger and thicker they are the more heat they'll conduct from the inside to the outside. How heavy is the finished door? The only way to test it is to use it. Can you report on its performance for the benefit of members?

[Dino_Pizza]

Hi David, nice to chat with you again.
The door is 12.5 pounds (5.7kg).

DAY1 …..After a pizza fire, it was well saturated at 650°F when the door went on.
DAY 2 ….12 hours later it was 470°
DAY 3……24 hours later it was 250°
(I did cooke a brisket later on day 2 and it was still 400°F)

The put the IR thermometer gun on the face of the door each day and it was 150° on DAY 1&2 and 125° on DAY 3.
My oven arch walls were also 150° the 1st day, same as the metal door.

This was my one and only use of the door. I’ll make notes again next time,it is summer and quite warm here.
Thanks, Dino,

[david s]

Hi David, nice to chat with you again.
The door is 12.5 pounds (5.7kg).

DAY1 …..After a pizza fire, it was well saturated at 650°F when the door went on.
DAY 2 ….12 hours later it was 470°
DAY 3……24 hours later it was 250°
(I did cooke a brisket later on day 2 and it was still 400°F)

The put the IR thermometer gun on the face of the door each day and it was 150° on DAY 1&2 and 125° on DAY 3.
My oven arch walls were also 150° the 1st day, same as the metal door.

This was my one and only use of the door. I’ll make notes again next time,it is summer and quite warm here.
Thanks, Dino,

That's pretty good 5.7kg is pretty manageable. Can you touch the bolts that run right through the door on the outside? I assume not as the temps you recorded suggest.

[UtahBeehiver]

That's a good way for non welders to build an insulated door. Thanks for sharing on the blog.

[Dino_Pizza]

Thanks UtahB,
and the final door did not have all 8 of those SS u-brackets as on my test door out of cardboard, just 6 you see holding in the insurance in one pick. That six made it sturdy enough.

[Sixto]

Id love to get recommendations from the experienced builders regarding door insulation, I'm having a hard time sourcing cal-sil board, so I'm considering 10:1 perlcrete or rockwool board (called ProRox 960 which indicates an R-5 per inch?) whichever I go with would be fully encapsulated in stainess steel. I guess I'm trying to see which one would do a better job of insulating per inch of thickness...

I will probably end up with 2 doors, the insulated door to keep residual heat for as long as I can, and a plain SS plate door to control air/smoke and minimize rain infiltration.

A question about Stainless, i've read that it warps, is there a minimum gauge I should use for the inside face on the insulated door... what about if it's a plain non-insulated metal plate?

Thanks to all for a helpful thread!

[MarkJerling]

Id love to get recommendations from the experienced builders regarding door insulation, I'm having a hard time sourcing cal-sil board, so I'm considering 10:1 perlcrete or rockwool board (called ProRox 960 which indicates an R-5 per inch?) whichever I go with would be fully encapsulated in stainess steel. I guess I'm trying to see which one would do a better job of insulating per inch of thickness...

I will probably end up with 2 doors, the insulated door to keep residual heat for as long as I can, and a plain SS plate door to control air/smoke and minimize rain infiltration.

A question about Stainless, i've read that it warps, is there a minimum gauge I should use for the inside face on the insulated door... what about if it's a plain non-insulated metal plate?

Thanks to all for a helpful thread!

See my post #141 above. I used either 0.9mm or 1.2mm thick stainless steel, I can't remember which. Following below my post, a few posts down, is a similar design to mine, but made nicer than mine! While the stainless steel sheet facing the oven warps slightly when the oven is hot, it soon returns to flat as the oven cools.

I now also have a thin aluminium "outer" door which I use to keep the weather out.

[Sixto]

That sounds great for the Stainless or Aluminum, Thanks Mark! Any suggestions about the insulation material if I can't get calcium silicate???

[david s]

I came at it from a different angle. I like the look of a wooden door as it's traditional for Italian ovens. But the problem is that it burns if it gets to 250C.The Italian's solution was to soak the door in a bucket of water prior to fitting it.If it charred up badly they'd just make another.
Using a highly conductive material like stainless or aluminium as a facing for the door, where you are wanting it to insulate seems counter productive.
My solution, which does have its drawbacks, is to use a 20mmm wooden door with a cast 20mm insulating panel bolted to it using 3/16" 316 stainless bolts, being as thin as I dared to reduce conductivity, and with the panel held away from the wooden door with high temp silicon to reduce heat travel by conductivity.
I've arrived at this solution mainly due to fabrication time and appearance.
The insulating panel needs to be fairly light and insulating, but at the same time durable. This is not easy because you can make it stronger but that reduces insulation value. Making it more insulating makes the panel lighter but very susceptible to wear and damage. A compromise somewhere in the middle is how I now do it.
I works pretty well, but you can't place the door after a pizza cook up and expect it to hold the heat the next day because the door will burn. Because my oven is small it's no big deal to flash it up again, but for roasting and baking with the oven below 300C, the 20mm of insulation does a fine job of both holding the heat and protecting the timber door.

The one handed operation is also a bonus with the door's total weight only 3.3kg

[Sixto]

...My solution, which does have its drawbacks, is to use a 20mmm wooden door with a cast 20mm insulating panel bolted to it using 3/16" 316 stainless bolts, being as thin as I dared to reduce conductivity, and with the panel held away from the wooden door with high temp silicon to reduce heat travel by conductivity...

Thanks DavId!, I like the wood look and functionality also. Can you share more details about the cast insulated panel? is that a perlite/vermiculite and cement mix? If so, what ratio would be strong enough to face the fire directly, and would you recommend a leaner, more insulating mix if you had a metal layer facing the fire?

[david s]

Because earlier versions of the insulating panel were not really strong enough, they wore out with a fair bit of use. I had used mill board which is about as strong as calcium silicate board. The cast panels I have developed use a 4:1 mix of sand and calcium aluminate cement to a depth of around 3mm which becomes the face of the panel sitting against the oven mouth. I then immediately make up a mix of 125ml calcium aluminate cement,500 ml sand and 700 ml medium grade perlite and some AR glass fibres and some pp fibres. For added strength I also embed three 6mm round steel bars into the centre of this layer for added strength. This is enough to fill the remaining 17mm of mould thickness. On remoulding 24 hrs later I wrap the panel in plastic for a further two days.
One big advantage of calcium aluminate cement, apart from its ability to withstand higher temperatures than OPC, is that it achieves its full strength after 24 hrs, although I always give it a couple of days to be sure. It has taken me a long time to arrive at this brew because the panel can be made stronger with the addition of more cement, but that reduces its insulating capacity. The richer mix for the face that faces the heat and sits against the oven mouth does a good job of strengthening that part. A metal facing is an alternative solution, but because it is so conductive is working against you to work as an insulator. It also increases the door weight substantially and introduces a third layer of material which adds to the fabrication costs in terms of labour and materials.I have considered doubling the panel thickness but that would increase the weight, make handling the door more difficult and the door would require two handles rather than one. This modification would also increase cost of materials and labour. For folk making a one off door the extra labour and materials are probably not a factor.