Commercial fridge build.

[muralboy]

This may be a dumb question - but how does someone handle the insulation issue with a standard old residential refrigerator conversion?  Is there a different type of insulation used in those units or is it easier to access the interior?

 

[cedar eater]

 
This may be a dumb question - but how does someone handle the insulation issue with a standard old residential refrigerator conversion?  Is there a different type of insulation used in those units or is it easier to access the interior?

If you get one old enough, it will have fiberglass or rock wool insulation instead of foam insulation. Those are naturally fire resistant and neither melt nor degrade from heat. Some also have some paper type insulation in the doors. If it has fiberglass insulation, it can be "glued" to the walls of the outer and/or inner shell with tar, which you can choose not to try to remove.

 

[sawinredneck]

I would be curious about how you could get a hot wire down the back, especially if there is anything it would catch on. But if you can do it in a well ventilated fire safe area, you might be able to just heat the metal lining enough to melt the insulation. I think an electric "heat gun" paint stripper might be safer than a torch for heating galvanized.

There was another builder that used rebar to get a chainsaw chain through to cut it out. Use the rebar to punch a hole then bailing wire to feed the thinner wire through the hole, or all-thread, or smaller pipe etc.

 

[madman mike]

There was another builder that used rebar to get a chainsaw chain through to cut it out. Use the rebar to punch a hole then bailing wire to feed the thinner wire through the hole, or all-thread, or smaller pipe etc.

that builder also had a stainless interior if I recall correctly. With the fridge were talking about here it has a very thin galvanized sheet metla interioir, very easily dented and punctured.

I really hate ton say it but they are not good fridges to convert to smokers, its a lot of sweat and $$.

The only way to get at the insulation is to open them up one the top and or bottom, and unless you separate the inside and outside you wont be able to properly clean the polystyrene off the walls. you will destroy the inside walls getting it apart and never mind cleaned. the walls are riveted together and the seams are often bent inward so the insulation actually works to hold it all together.

it can be done, but man its a huuuuge expensive conversion.

 

[sawinredneck]

I fail to see how a hot wire can hurt the interior walls? I don't have to use rebar, there are many options for creating a hole and passing a thin wire through. As you put it, it seems like I'm trying to create the Grand Canyon with a spade shovel?
Ever seen a Colman "gas tree"? I was one of the machinist that built the machine that makes them. First time I'd ever seen a thermal drill bit. Own a Rubbermaid cooler? Chances are I worked on that blow mold some time or another. Got a "Peter pump"? Yeah, I worked on that one as well.
I retired from machining when I got pigeonholed as a five axis operator that was skilled with titanium.
There are lots of ways to think outside the box, look at wire edm and sink die edm for starting examples. Then look at how surfboard cores are formed with hot wires.
Don't dismiss things just because you can't understand them please.

 

[muralboy]

So problem solving here guys....let's assume The walls are thin and either the inside or outside wal is going to get damaged.
-Why not maintain the integrity of the outer shell and frame and gut from the inside by removing the inside walls
- strip the foam back as far as you can
- increase the wall thickness slightly for added insulation
- install new interior walls

It will be a few $$ but considering the costs, still got to be cheaper than buying a unit of this size. Might help to make friends with a welder if you don't know one already
Gonna take some sweat equity and time, but almost everything we love doing here takes time and effort - 14 day dry cures and 12+ hr smokes.

Half the fun is the satisfaction of completing the task.

Don't lose heart. Good luck.

 

[cedar eater]

So problem solving here guys....let's assume The walls are thin and either the inside or outside wal is going to get damaged.
-Why not maintain the integrity of the outer shell and frame and gut from the inside by removing the inside walls
- strip the foam back as far as you can
- increase the wall thickness slightly for added insulation
- install new interior walls

It will be a few $$ but considering the costs, still got to be cheaper than buying a unit of this size. Might help to make friends with a welder if you don't know one already
Gonna take some sweat equity and time, but almost everything we love doing here takes time and effort - 14 day dry cures and 12+ hr smokes.

Half the fun is the satisfaction of completing the task.

Don't lose heart. Good luck.

I just bought painted metal roofing to cover over my deck when the tarp that I've been using succumbed to a hailstorm. It looks like it would be a good metal for inside a smoker. It cuts easily enough with a circular saw and it has ridges every nine inches that could be used for racks. Adding a piece of J-channel in between those ridges would get you  4.5 inch rack spacing. The paint is well baked on and would get well seasoned.

 

[mneeley490]

There was another builder that used rebar to get a chainsaw chain through to cut it out. Use the rebar to punch a hole then bailing wire to feed the thinner wire through the hole, or all-thread, or smaller pipe etc.

Actually, it was a length of 3/8" threaded rod. Not quite as thick as rebar. Taped the chain to one end and pulled it thru. The same could probably be done with a hot wire.

 And yes, the interior was stainless steel. It was a tough build, but in the end I think it was worth it. Would have been a lot easier if they could invent some solvent that will melt poly foam.

 

[sawinredneck]

Well.... There is always MEK?

 

[mneeley490]

Well.... There is always MEK?

Tried MEK and everything else on the market, including unlit gasoline. Nothing removes it except elbow grease.

 

[sawinredneck]

Aren't you just a shining ray of hope, lol!

 

[madman mike]

you may be able to cut the foam out with a wire, but you still have to clean it off the interior walls. I tried a conversion with a cooler just like yours, but a single door. If you have the time and $ go for it. Personally I don't see the reason. Easier and cheaper things to make a smoker out of.

Ill def enjoy watching the build and look forward to learning from it as I have every other build ive followed. Just thought I would add my 2cents from experience.

 

[sawinredneck]

Man, you guys are killing me here! Sounds like I just need to buy a custom trailer instead?

 

[mneeley490]

 
you may be able to cut the foam out with a wire, but you still have to clean it off the interior walls. I tried a conversion with a cooler just like yours, but a single door. If you have the time and $ go for it. Personally I don't see the reason. Easier and cheaper things to make a smoker out of.

Ill def enjoy watching the build and look forward to learning from it as I have every other build ive followed. Just thought I would add my 2cents from experience.

Hahaha, you got that right!  I'm not sorry I built mine, I'm still having a lot of fun with it. But if I ever do another, it'll be with a vintage fridge.

 

[madman mike]

look around at auctions places that does a lot of restaurant equipment. this is one im watching right now a few hours away from me. http://mcdougallbay.com/bid.php?arg=782FE9CB-B1CE-49A0-A203-47187C3087BE

 

[cedar eater]

Man, you guys are killing me here! Sounds like I just need to buy a custom trailer instead?

You won't know until you try it. I thinks it better to know that you have a daunting task ahead of you, but it sounds like you already did. I'm sure you can keep the cost down some by increasing the amount of time you devote to it. You just have to be willing to do that. Cutting it apart with a hot wire sounds like an interesting approach. Maybe once you do that, you can burn or melt the foam off at temperatures below the boiling point of the zinc and the scorch point of any paint or other coating that you want to keep.