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Discussion in 'Fridge/Freezer Builds' started by porkbelly, Nov 9, 2010.

  1. porkbelly

    porkbelly Newbie

    hi, i have seen a lotta post in here saying if you use the newer fridge you need to strip out the foam...yet i just took the back off my cajun injecter and there it was full of foam...is there a differents in that foam and the foam used in newer fridge...i have no clue thats why i'm asking....if not it would save a lotta work..ty   Billy
  2. eman

    eman Smoking Guru Staff Member Moderator OTBS Member

    Everything i've seen was to remove the plastic interior not the insulation.
  3. tjohnson

    tjohnson Smoking Guru Staff Member Moderator Insider OTBS Member SMF Premier Member

    Yup, Polyurethane Foam is OK, but you gotta take out all the plastic.  Some old appliances may have used "Rock Wool" and that actually fire retardant.

    Polystyrene foam is not heat resistant enough for high temps in a smoker.

  4. porkbelly

    porkbelly Newbie

    hi guys, yes i knew about the plastic...i'm hoping to do another fridge mod. one day and don't think i'll be lucky enough to find and old 1 like i have so i was just wondering...ty for ur comments....Smoke On
  5. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Hi all,

    I'm new here, just starting my first build. I picked up a Victory stainless steel restaurant-type single door fridge and have just finished gutting the components. Now I'm looking at the insulation. The specs for this unit say it is "foamed in place polyurethane".  I just want to make sure that the concensus here is that polyurethane is ok? The factory seal on this thing is very tight, and I really do not want to tear it apart if I do not have to. I plan on making this an electric smoker, so temps probably will never go much over 275 or so. Inside and out is all stainless steel, except for the inside of the door and some door trim, which I will have to replace.

    So please tell me you all think polyurethane is ok, as that would save me a LOT of time and trouble. I will have pics of this build posted soon.

    Mike in Everett, WA
  6. michael ark

    michael ark Master of the Pit

    Bad news .It's not ok.
  7. Bearcarver

    Bearcarver SMF Hall of Fame Pitmaster Group Lead OTBS Member

    Poly & heat don't mix.

    If you're talking about the same polyurethane I'm thinking of, I did a test when I was young & stupid (as opposed to old & stupid).

    I held a strip of polyurethane between my fingers. The strip was about 2' long.

    I lit my cigarette lighter and touched it to the far end of the poly, figuring if it burns, I can just drop it.

    It went up into a ball of flames, and got to my hand before I had time to let go.

    It stuck fast to my hand, and hurt like Heck, until it cooled off. Then I had a few blisters for awhile.

    All I remember is the "Whooof" noise it made, one tenth of a second before it hit my hand!

  8. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Well, dang. I thought I might have caught a break.
  9. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Well I've stripped out everything but the stainless steel inner lining. It is stuck in place by the blown in foam. Getting the foam out (and getting to it) has become much harder than I thought.

    Does anyone know what might dissolve it? I've tried lacquer thinner and it was like throwing water on it. A stripper with methylene chloride softens up the first inch or so, but doesn't do anything else.

    Looking at finding some methyl ethyl ketone (MEK) now. I've heard it might work a little better.




    Last edited: Jul 4, 2011
  10. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Well evidently there is nothing known to man (other than fire) that will dissolve polyurethane foam. So still doing it the hard way. I poked a hole all the way through it with a steel rod, then threaded 7 feet of chainsaw chain through the hole. Duct taped both ends for handles, and used it like a bucksaw to go all the way around the 3 sides. Took about 1-1/2 hours that way, but they are apart. Still scraping all the sticky foam from the nooks and crannies. Man, I hope this will be worth it.
  11. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Short update: I painstakingly scraped the remaining foam from both the outside shell and the inside liner. What residue was left, I took a blowtorch to and burned it off. Fire good.

    Now comes the arduous task of reassembly and conversion to electric. I still have to find a 240v element to mount inside. 

    Just a warning to others: If I had known then what I know now, I would not have started out with a fridge containing polyurethane foam. Had I an older fridge (which I now see can be had sometimes for free on craigslist), I would go that route instead. Perhaps next time.
  12. mavrick813

    mavrick813 Smoke Blower

    I would think a piece of piano wire may have made the task a lot easier. Anyone here ever empty one out and blast it with a Roofing torch? Bypass the scraping all together??
  13. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Wire was the first thing I thought of, but I couldn't find any that was abrasive enough. Believe me, this foam is e'ffing TOUGH. As I posted above, one and a half hours of sawing back and forth with a very sharp chainsaw blade. And several more hours of scraping. Heck, I started this back in June and now I'm almost finished. I'll post pics of the project in another thread. 

    I used a torch for just the residue. I filled 4 big, black yard waste bags with all the foam I took out of this thing. Burning that much foam would have sent a column of black smoke high over the neighborhood and ruined whatever it was sitting on, which was my driveway. And my next door neighbor is a fireman.
    Last edited: Dec 15, 2011
  14. ankorklankor

    ankorklankor Newbie

    I'm working on a SS fridge that looks very much like yours, I don't know what kind of foam is in it but plan to remove it all and replace with mineral wool.  I have a 2 man saw that is about 5 ft long and will try to saw the foam to separate the sides if that doesn't work I will try the chain saw chain method that you did. 

    I called the company that made it and they would not even talk to me about the type of foam they use, they are not willing to get involved and didn't want the liability I can understand that but they could have at least told me what kind of foam it is.

  15. how about building a fire in side would that melt out the foam and then just have to clean it up after?
  16. mneeley490

    mneeley490 Master of the Pit OTBS Member

    Well, I think you have to remember that the smoke & fumes from this stuff is supposed to be toxic. So flame it at your own risk. I wore goggles and a respirator when I burnt off the residue, and even that made a substancial amount of smoke. I'm not sure it would melt without burning.
  17. dward51

    dward51 Master of the Pit OTBS Member

    When you burned the foam, was it pretty obvious it was not going to work "as is"in the smoker?

    I've seen posts both ways and apparently there is more than one kind of polyurethane used in these things.  The one post above indicated his poly woofed so fast he could not even drop it when he tested a strip.

    I know yours was a Victory fridge unit, but I'm considering a Victory warmer conversion and their spec sheets show the unit as 1500 watt heating elements and a normal operating temp is 150 to 180 with the max of 220.  I'm thinking either they used a different foam than the "woof" post had in it.  I would just as soon not have to go through what you did in your Victory fridge dissassembly if I can avoid it.  If their max spec is 220 and we are smoking at 225-235, I can't imagine their foam only has that narrow a safety margin above the 220.

    With a torch, I would imagine any foam will burn at a certain point. I guess my question is how volatile did the Victory fridge foam look when you burned it out?
    Last edited: Apr 14, 2012
  18. mneeley490

    mneeley490 Master of the Pit OTBS Member

    It did not go up like napalm like Bearcarver's foam. But once flame touched it, it did shrivel and turn black, and send out some acrid smoke.

    Try emailing Victory and see what they recommend. As yours was a warmer, it might be a different kind of poly. I just knew that I didn't want to get the dang thing built, then have to tear it apart again.
  19. dward51

    dward51 Master of the Pit OTBS Member

    That might be a good sign as heat from a torch would have been way above what we are looking at in a smoker.  Given enough heat, pretty much anything synthetic will shrivel and turn black or burn.

    I will try to contact Victory, but I suspect the response will not be conducive to modification of their product for liability reasons.  If their warmer system can be run at up to 220* I just can't see the danger zone being very close to that.  There would have to be a huge margin of error for those same liability reason.

    Well, the wildcard is "IF" I can get the warmer at a decent price to make it worth my while to strip it down.

    Other that that, it's sounds like from the specs and manual all it needs is a smoke source.  It has an external heat/air circulation fan, moisture vent on top and two 750watt heating elements (one on each side at the bottom of the chamber). It has a analog dial temp setting but a digital temp sensor readout (not a digital controller though).  I would replace the analog control with an Omega digital one and SSR, but might could still use the existing separate digital temp module with another probe as a meat temp readout.  Sounds like the only thing missing is a Amazin Pellet Smoker and a fresh air intake for the pellets "as is" (assuming the blown in foam is safe for the mid 200's).