Replicating Styrofoam "Lego" Piece in Black Tank Pan

[ashleyfigs]

I've had a hard time finding an answer, so I figured I would start a new thread.

The blank tank pan in our 1968 Ambassador originally had a styrofoam "Lego" looking piece inside of it under the tank itself. From my research it seems that this piece served as both insulation and kept the tank at the right angle to drain properly. Our original styrofoam piece was in okay condition and we may have considered re-using it, but our neighbors' chickens thought it was a tasty treat and pecked away at it, making it unusable.

So my questions are:

1) If you replicated this foam piece, did you use styrofoam or another foam material and why?
2) What is the best way to cut this piece?
3) Do I need to replicate the raised "Lego" circles for aeration (or some other reason) or can I just replicate the angle with a smooth piece of foam?

Thanks!

[mikextr]

Following. Will be doing this job soon.

[Al and Missy]

I'm tacking on here because I have a similar problem. In a previous post I described trying to replace the dump valves without completely dropping the pan. I lost that battle and had to drop the pan.

Even before I completely dropped it, pieces of styrofoam sheet came from everywhere. It was impossible to determine where they all came from and further, it was obvious that the pan had been dropped and replaced before because there were two pieces that were crushed at different angles from the floor joist running across the trailer between the two tanks. I did stuff the long rectangular pieces between the tanks and the frame parts to keep the tanks from moving fore and aft and put the larger pieces that were obviously under the tanks back under the tanks.

I am now trying to put the pan back and despite my best guesses based on lines on the inside of the pan that seemed to indicate tapered pieces of styrofoam under the tanks, the pan is bowing at the front/rear center near the points where the drains exit the tanks. It is as if the styrofoam there is too thick. As the OP said, I think the foam serves a dual purpose - insulation, and as shims to take up the slack between the pan and the tanks to provide adequate support.

I want to be sure that the tanks have adequate support particularly around the shower and toilet drains so as not to put stress on the drains but I don't want to push the drains up either.

Should I just tighten it up or try to equalize it by removing some of the foam under the drain area?

Thanks,

Al

[TomW]

Here's what I did in 2004:

http://home.hiwaay.net/~tomorkim/BoxInsulation.htm

It has held up well.

Tom

[A W Warn]

You might contact a local commercial/industrial roofing contractor, hoping to get lucky enough to find some tapered insulation scraps. Roofer's use this to create crickets (slopes) to direct water to a drain on flat or low sloped roof structures. If they do not have a scrap piece, they might direct you to a supplier.

If it were me, I would be tempted to use flat sheets of blue board insulation. Or, cut my own slope using a wood rasp. Since a trailer is always moving, my opinion is the tapered insulation is not needed. Using a wheel block to enhance drainage works just as well.

(If you cut insulation be extremely careful to not breath any particles. It collects in lungs and is there forever)

[Al and Missy]

Originally Posted by TomW

Here's what I did in 2004:

http://home.hiwaay.net/~tomorkim/BoxInsulation.htm

It has held up well.

Tom

Thanks! Airstream obviously took a lot more care in 1967 than they did in 2002. I'm thinking I could get a sheet of styrofoam and cut out some pads with a piece of sharpened PVC pipe. The trick is going to be getting the height right.


Al

[Al and Missy]

Originally Posted by A W Warn

You might contact a local commercial/industrial roofing contractor, hoping to get lucky enough to find some tapered insulation scraps. Roofer's use this to create crickets (slopes) to direct water to a drain on flat or low sloped roof structures. If they do not have a scrap piece, they might direct you to a supplier.

If it were me, I would be tempted to use flat sheets of blue board insulation. Or, cut my own slope using a wood rasp. Since a trailer is always moving, my opinion is the tapered insulation is not needed. Using a wheel block to enhance drainage works just as well.

(If you cut insulation be extremely careful to not breath any particles. It collects in lungs and is there forever)

Thanks Alan. The tapered foam is used (I think) because the tanks are tapered to the drains. The gray tank drain is not at the end, but about 2 feet from the roadside end so it may need to be supported with foam sloping up from the drain to the roadside end.



Al

[jessl_99]

Originally Posted by TomW

Here's what I did in 2004:

http://home.hiwaay.net/~tomorkim/BoxInsulation.htm

It has held up well.

Tom

Just curious did you make a new galvanized sheet metal box for the tank or use existing.

[TomW]

I made a new one:

http://home.hiwaay.net/~tomorkim/GalvanizedBox.htm

Tom

[jessl_99]

Originally Posted by TomW

I made a new one:

http://home.hiwaay.net/~tomorkim/GalvanizedBox.htm

Tom

Great work. I like the bed frame recycle too. I am considering epoxying together a plywood box and then coating the whole thing with epoxy.

[Trnpk Crsr]

I think that “Leggo” pieces were intended to provide gaps for warm air from the furnace to circulate under the take to keep it from freezing.

Cheers,

John