Aerogel - Spaceloft Insulation for Fridge / Freezer

[bartonman]

Amazing Job Weyalan. What a great use of space.

[Weyalan]

Originally Posted by lateral

Great Job! Specially like the radii- easy to keep clean.
What paint did you use for the white? Spray or brush?

The paint is all Wattyl product.

All the white surfaces are first treated to a coat or 2 of 2-pack timber preserver (also Wattyl), then 2 coats of high-build 2-pack undercoat (UC230, from memory), then 2 coats of 2-pack top-coat (Poly U400).

The paint is rolled on with a 4" short nap mohair "finishing" roller

[Weyalan]

For what it is worth:

I noted that with the freezer sitting at a happy -5 deg C, the compressor ran 10 minutes then off for about 75 minutes. The thermostat was only turned just under 1/4 of the way from "off" to "max"

[lateral]

Originally Posted by Weyalan

For what it is worth:

I noted that with the freezer sitting at a happy -5 deg C, the compressor ran 10 minutes then off for about 75 minutes. The thermostat was only turned just under 1/4 of the way from "off" to "max"

Bugg@r! We just redid our freezer last year with foam. Hadn't been exposed to aerogel then.

Did you do all your radii with 411? Also, the nap size of the mohair roller & how many coats of U400?
Sorry for the inquisition; Sure beats fubars tho'.

Thanks!

[Weyalan]

Originally Posted by lateral

Bugg@r! We just redid our freezer last year with foam. Hadn't been exposed to aerogel then.

Did you do all your radii with 411? Also, the nap size of the mohair roller & how many coats of U400?
Sorry for the inquisition; Sure beats fubars tho'.

Thanks!

I'm happy to answer as many questions as you have, nevertheless, be warned - wife and I are very much in the "enthusiastic amateur" class of boat refitters - no professional training or qualifications.

The rollers are, I'm pretty sure Uni-Pro 100mm mohair rollers similar to those shown in the following (eBay) link
Uni-Pro 10 Mohair Roller Covers 100mm Mohair Baby Roller Covers | eBay
At a guess I'd say the nap is about 3 or 4mm... not much at all.

We generally use 2 coats of Poly-U400, with a very light sand (240 grit) between coats. The small roller is pretty good for tight spots, but we still use a brush for "cutting-in" where required.

The fairing and coving are all done with R180 epoxy resin and whatever filler powder we had at the time - maybe West microballons for that part of the project (I don't think that there is all that much difference between them). My wife generally does all the coving (while I mix the resis & filler) - she has better skills than me in that area. I whip-up coving sticks from offcuts of tinber or ply to suit whatever size fillet she requests. For what it is worth, the large radius on the front corner of the stool / locker is 6mm bending foam, set into the 9mm ply faces, with a layer of glass inside and out, faired, sanded and painted.

[George64]

I read the whole topic, impressive. If I want to insulate my fridge, probably more or less rebuild the box in my boat and don't want to spend the money for Cryogel, would this be a reasonable/good alternative for insulation:
Unidek Polydek Spouwisolatieplaat 2,5 RE EPS 124,5x71,5 cm dikte: 83 mm wit - Polystyreen platen

(RC-value of 2,5m² K/W)

[foggysail]

Originally Posted by Weyalan

I'm happy to answer as many questions as you have, nevertheless, be warned - wife and I are very much in the "enthusiastic amateur" class of boat refitters - no professional training or qualifications.

WOW!!! A project you and your wife are surely proud to display!!! Superb job!

Question-- in your opinion, is it possible to spray the epoxy or fiberglass resin rather than apply it with a brush or roller? After reading this thread, just thinking of making my own box fridge to set out on my rear deck whets my intrest...after current projects get finished.

Spraying could eliminate or at least greatly minimize sanding. I have not tried sanding fiberglass resins but I have sanded epoxy resins. That is a big PITA. Sandpaper quickly fills with the sanded resins, not an easy job.

Foggy

[foggysail]

After a quick Google--

Well, so much for spraying either epoxies or polyester resins. Dumb idea. Health hazards too great, not even sure if epoxies can be sprayed, equipment too expensive and +++

Foggy

[Weyalan]

Sorry for the slow response, foggysail. I don't know if epoxy resin could be sprayed, but I can't really see why not, provided you have a good mask and filter, glasses, etc. (we use Sundstrom) and reasonable ventilation. I personally wouldn't bother with spraying resin, but I would have given spraying the 2-pack varnish a try, if it wasn't for the fact that we were working inside the boat the whole time... we couldn't get the bench top out ... it was too big! But yes, in theory, sparaying of 2-pack varnish could have, potentially, saved some sanding.

[Weyalan]

Just a quick update... we got on to a good school of Australian salmon on Saturday and ended up with about 5kg (11 pounds) of fresh fillets that evening. We put these in the freezer (minus dinner) and ramped it up and by next morning they were solid frozen

[Roy M]

I guess I missed something, so please bear with me. Assuming one places a one inch thick vacuum insulated panel between two one-inch thick aluminized polyurethane panels, resulting in a three inch thick insulation, not counting the inner and outer wall thicknesses, how does an aero (or any of its kin) gel offer superior insulating qualities for the price?

I am assuming that the final assembly includes an air and vapor proof barrier between the insulation and the interior or exterior of the sandwich.

I ask this because I am on the point of purchase of my super-insulation panels so that I can complete my new reefer box. And, where can I purchase three inch wide Aerogel strips in the USA? I might include these on the "end-grain" of my insulation sandwich between the box structure and the three inch cap structure which includes the hatch lids, made by RParts and filled with vacuum insulated panels (VIPs).

[foggysail]

Those of you who built your own stuff, how did you incorporate the evaporator? Are you using something mounted against an interior wall, recess it in an interior wall or did you run copper tubing under the fiberglass barrier between the insulation and the box interior?

Although I still have an unfinished project...that will get done during the winter, I want to explore building a refrigeratored chest to sit on our rear deck. I often have to change a refrigerator in our apartments so if I find one that uses R134a, I intend to rip out the compressor and condenser. That will be the easy part, just have not conceived how the address the evaporator.

Another question-- do you have an interior icing problem that requires manual defrost?

Thanks--

Foggy

[senormechanico]

foggy,
For mine, see post #51 of this thread.
I used 3M 5200 as an adhesive on the outside of the liner to adhere SS strips, drilled and threaded so I could mount the evaporator from the inside with machine thread fasteners.

[Weyalan]

Originally Posted by Roy M

I guess I missed something, so please bear with me. Assuming one places a one inch thick vacuum insulated panel between two one-inch thick aluminized polyurethane panels, resulting in a three inch thick insulation, not counting the inner and outer wall thicknesses, how does an aero (or any of its kin) gel offer superior insulating qualities for the price?

I am assuming that the final assembly includes an air and vapor proof barrier between the insulation and the interior or exterior of the sandwich.

I ask this because I am on the point of purchase of my super-insulation panels so that I can complete my new reefer box. And, where can I purchase three inch wide Aerogel strips in the USA? I might include these on the "end-grain" of my insulation sandwich between the box structure and the three inch cap structure which includes the hatch lids, made by RParts and filled with vacuum insulated panels (VIPs).

You can buy SPACELOFT (Aspen Aerogels) on eBay.
3/8" costs $5 per square foot. It comes of a 57" wide roll, so you can buy as much as you need and cut it into strips. I have no idea if $5 per square foot is a good price for this material, nor do I know how this compares to the cost of vaccum insulated panels.

I think if you trawl through the last 2 or 3 pages of this thread there is a post by a SPACELOFT vendor in the USA.

To me, the big advantage of SPACELOFT over vacuum insulated panels (VIP) is that you can bend it, fold, it and cut it into whatever shapes you want. Obviously, VIP has higher R value, but their disadvantage relative to SPACELOFT is their relative fragility and the contraint of not being able to bend and cut to shape. I guess it is all about horses for courses.

[foggysail]

Originally Posted by senormechanico

foggy,
For mine, see post #51 of this thread.
I used 3M 5200 as an adhesive on the outside of the liner to adhere SS strips, drilled and threaded so I could mount the evaporator from the inside with machine thread fasteners.

SenorM--

Yes, I had glanced at that earlier, should have looked closer at it. I THOUGHT IT WAS A COMMERCIAL BOX!! GREAT JOB! Fiberglassing!!! Your box along with the others pictured in this thread are awesome! That will be a challenge I will share later as I get further into the project. I just cannot get a thing done during the late spring, summer and early fall. There are just too many demands made on my available time. Off topic-- I have followed your posts along with others on solar. I mention it here only because my added refrigeration is going to rely on my current 390watt installation coupled with another 390 watts (two 145 watt DM panels) that are still contained in their original shipping container that I will install next season. Power should not be a problem.

OK, back on track--- I see the mechanical box mounted as shown in your pictures that I presume is your evaporator. Did you build that, purchase it or is it from a salvaged unit? How are you addressing defrost? I expect to see the evaporator ice up even if the box is kept below freezing or am I overestimating the problem?

Last summer I just got fed up with ice hauling to our Igloo cooler. Thought about purchasing an Engel box. I decided to make my own knowing there will be little if any cost savings but it will be what I want.

Foggy