1980 Caravelle Shell Off Renovation

[timzog]

Originally Posted by perryg114

Well for the ribs to do anything they need to be attached to the bottom or top skin, preferably both. Flush rivets would be good or counter sunk stainless screws. You want to create an I-beam out of your materials. You have the stringers going in the right direction though. Spot welding would be ideal if you had the rig for it.

Perry

I didn't understand your question before, since I was thinking you were talking about the main ribs that separate the skins in the trailer shell. I am using 1/8" pop rivets spaced at 2" to attach the bottom skin to the homemade aluminum C channels (I believe this is what you called the ribs). The bottom skin is attached to the steel frame using 3/16" aluminum rivets with big heads.
I attached 6 stringers to the bottom skin today. With 24 rivets per each piece of C channel, that's a lot of rivets to pull by hand, but I hope that I'll develop massive forearms by the time this is done.

The top skin will be attached by 1/8" aluminum countersunk buck rivets where I can access both sides and blind rivets where I can't. Around the perimeter, it will be attached with 1/4" stainless bolts secured with locktite. Based on some good advice from Wabbitteer, I will use lots of rivets in the middle of each sheet to create a fixed point that will allow the sides of each sheet to expand equally upon changes in temperature.

[ddstech]

Originally Posted by timzog

Started work on the bellypan.
Used 1/16" x 1 1/2" angle to frame around the front of the grey tank. Buck riveted the .0625 5052 sheet to the angle and attached it to the frame with 3/16 rivets.

Used 3/16" pan head rivets from vintage trailer supply to attach the .032 5052 bellypan to the frame. Used a 4 x 10 sheet cut into two 5' lengths to span the main frame members and leave 3" on each side which I will use to attach to the curved section of the belly wrap around the perimeter.

My biggest regret is doing my belly pan after putting the shell back on. I was not able to put all the pieces together in my head so i opted to do it after. Looking good!

[timzog]

Attached a few small sections of bellypan to the odd shaped section in the front around the spare tire holder. Since I had it lying around I used .0625" aluminum for this. I had to cut around the brackets for the spare tire holder. Used 3/16" rivets to attach to frame and overlapped it over the main bellypan piece, pictures of this didnt come out well which seems to happen often when taking pictures of reflective surfaces. I then insulated this area using foam again, Used 2" and 1" foam to fill the 3" depth.
Then I started putting the floor assembly together. First had to learn how to do countersunk rivets. Best tool ever is a micro stop countersink tool which allowed for incredible precision in countersink depth. Attached 4 3" wide pieces of 1/8" aluminum as splices. Peg board is really useful for laying out things like this Left gaps in order to miss the frame. Used bucked 1/8" rivets to attach the two pieces. Started with a 1 inch spacing in two rows but realized pretty quickly that it was overkill so I went to a staggered spacing on the rest of the splices so it is basically two rows separated with 1" with a 2" spacing in each row.



I went ahead and used a can of spray foam to tighten up and seal any gaps in the solid foam and then immediately applied a bead of marine grade sealant (thanks Wabbiteer) to the top of the frame before putting down the front floor section. I used buck rivets wherever I could reach and since this is under the bed I used 3/16 pop rivets for the places I couldn't reach. I also used a couple stainless 14/20 machine screws with nuts and blue locktite in a few places.




Flush buck rivets. I still have to work on my technique a bit.

[timzog]

After a great vacation with my family in the NW, I had some time this week to work on my Caravelle.
I prepared the second sheet of flooring by flush buck riveting 3" strips of 1/8 sheet along th next leading edge to serve as a splice.
I bought an aluminum flush table base on eBay and attached it to the underside of the floor after drilling a hole for the the pedestal with a hole saw. It may be overkill but I used a ton of rivets to attach to the floor. I'll make a little circular cap so when we don't want the table it will disappear.
I applied a bead of marine adhesive and set the 2nd sheet in place. I am still in the process of riveting it all down. I am using 1/8" flush solid rivets wherever I can reach the back side. In the places that will be covered by cabinetry and I can't reach I am mostly using 3/16" pop rivets. In the places where I want the floor to be flush and I don't have access I am using 1/8" flush pop rivets- LOTS of them. In the places where I want lots of strength and I do have access I am also using 1/4" SS machine screws and nuts with locktite.

[timzog]

Here are some pics of the recent progress. Just two more sheets to go!!

[perryg114]

So how does the existing new floor handle you walking on it? Looks like you are making good progress.

Perry

[timzog]

Originally Posted by perryg114

So how does the existing new floor handle you walking on it? Looks like you are making good progress.

Perry

Thanks Perry,
It feels very secure and solid. There is no sign of deflection when I stand on it which is much improved over the old plywood floor. I'll have to stand in the middle of the biggest span and take a picture of a straightedge across it.
Tim

[timzog]

I put the third section of floor down yesterday. It is only about 200 rivets per section. I wonder if I am over doing it?

[Wabbiteer]

I'll only start worrying when you tear those floor panels out overnight to go with kevlar and carbon-fiber honeycomb reinforced panels.

Very little has been said about the shell and other trailering accoutrements...

Have you glommed onto the new range, dishwasher, washer & drier, central vac and sauna yet?

[timzog]

Originally Posted by Wabbiteer

I'll only start worrying when you tear those floor panels out overnight to go with kevlar and carbon-fiber honeycomb reinforced panels.

Very little has been said about the shell and other trailering accoutrements...

Have you glommed onto the new range, dishwasher, washer & drier, central vac and sauna yet?

Nope, trying to save room for the hot tub!

[timzog]

Plumbing question:
Is there any reason not to connect a shower drain directly to the exit of the grey tank? There would be a Hepvo trap between the two. Water always finds its level so it seems like it shouldn't matter whether the drain entered the tank from the top or side. It would be really easy to put a T on the exit of the grey tank and connect the drain to that. I can make it work to have the drain enter at the top but it will be a lot more fittings and I want as few connections as possible.
Tim

[Wabbiteer]

Good question for me too at this stage of my project

I'd be wary of setting up a temperamental drain line that may be partially air-locked... as in a slug of air that can't be pushed down or escape up and out of the way to allow full flow.

Does the shower drain pipe itself tie into a vent stack, and if so, where? What are the OD pipe sizes involved and how long is the pipe run and what is the vertical drop to the top of the GW drain pipe?

[Max Well]

I was just listening to Colin on the VAP and if I'm not mistaken he ties his drains into the drainpipe.

[timzog]

Originally Posted by Wabbiteer

Good question for me too at this stage of my project

I'd be wary of setting up a temperamental drain line that may be partially air-locked... as in a slug of air that can't be pushed down or escape up and out of the way to allow full flow.

Does the shower drain pipe itself tie into a vent stack, and if so, where? What are the OD pipe sizes involved and how long is the pipe run and what is the vertical drop to the top of the GW drain pipe?

With the hepvo traps, you don't need a vent for the drain line since they are self venting. I will have a vent for the tank itself. The drop from the bottom of the shower to the top of the inside of the tank is about 4 1/2". I am trying to figure out how to get the hepvo mounted horizontally at the midpoint of that distance and it will be easier if it goes into the drain instead of the top of the tank. If the hepvo is above the tank I am afraid that I won't have enough water above the valve to open it fully and get full flow through the shower drain. Of course if the valve is too low, it will not allow the grey tank to fill fully and wil l back up in the shower drain line.
The grey tank drain is 2" and the shower drain is 1 1/2". The runs will be short, no more than a few feet. I should be able to maintain 1/4" slope per foot throughout assuming that I can get my trailer level

[timzog]

Also, the top of the GW pipe is another 4" below the top of the tank so there is an 8" drop from the bottom of the shower to the top of the main drain pipe. I do think the most relevant issue though is the height of the water in a full grey tank.

[jm2]

Originally Posted by timzog

The grey tank drain is 2" and the shower drain is 1 1/2". The runs will be short, no more than a few feet. I should be able to maintain 1/4" slope per foot throughout assuming that I can get my trailer level

while fully recognizing that it's not the same exact assembly, you might take a look at a current national residential plumbing code for their stated limitation for "trap arm length".

that might give you an idea of where you design idea stands? that is, if the code says "3 feet" limit, and you're trying to go "2 feet", then you're likely to be ok.

[Wabbiteer]

Hepvo US Tech Guide

I fear the ventless description is being taken too literally - these folks speak in terms of multiple hepvo traps on a drain branch circuit allowing air INTO the system (admittance; cheater valve, mechanical) via the other hepvo traps; they mention 'full bore flow' as a positive aspect but that will only happen if the air in the pipes has somewhere to be displaced to.

Nowhere in their diagrams do they show the drain branch being completely ventless, terminating into pooled water & slightly pressurized, ie: the bottom of the tank.

We might be able to get away with it easier if we'd oversize the pipe to 2" after the hepvo trap, in regards to flow rate, but theres still the problem of pressurizing the line with 4-6 inches of water column... How does the bladder handle 0.25 psi on its discharge side?

[timzog]

Originally Posted by Wabbiteer

Hepvo US Tech Guide

I fear the ventless description is being taken too literally - these folks speak in terms of multiple hepvo traps on a drain branch circuit allowing air INTO the system (admittance; cheater valve, mechanical) via the other hepvo traps; they mention 'full bore flow' as a positive aspect but that will only happen if the air in the pipes has somewhere to be displaced to.

Nowhere in their diagrams do they show the drain branch being completely ventless, terminating into pooled water & slightly pressurized, ie: the bottom of the tank.

We might be able to get away with it easier if we'd oversize the pipe to 2" after the hepvo trap, in regards to flow rate, but theres still the problem of pressurizing the line with 4-6 inches of water column... How does the bladder handle 0.25 psi on its discharge side?

It seems to handle downstream pressure easily. Check this out.

http://www.youtube.com/watch?v=VbwUe...e_gdata_player

Regarding the venting, the trap only needs to be able to let downstream air through. The tank must be vented so that it can admit water without building pressure but I don't understand what else would need to be vented.

[Wabbiteer]

Gosh it would be easy to say you're absolutely right, lets launch and do it the easiest way . I'm looking at a 32-gallon 'shallow' tank and am pondering a grey water only plumbing system for my project & that option of ventless tie-ins to the main drain line sure is tempting.

Anyhow, a man'f selectively displaying certain design characteristics purely as benefits always makes me a little suspicious.

If it seals so perfectly to not allow ANY stack gas to back-flow and permeate the living area, then filling the GW tank will pressurize the shower drain tube and put hydrostatic pressure on the bladder. Sure, they show 'high' static back-pressure videos but do they show it passing fluids in normal installations when there is also some back-pressure built up?

How well does that bladder valve work when there is 6" water column (0.25psi) pressure against the discharge side? Does it require 6" of water column on the inlet side to overcome the higher-than-ambient (non-equalized) atmospheric pressure?

I don't understand what else would need to be vented...

One thing I see is maybe the hepvo already restricts the flow enough ("offering a minimal resistance to flow") that trapped air or suds foam will not impede the metered (reduced) flow rate.

In the design we're looking at, draining directly into a pool of standing water, is not an acceptable practice. Usually the air in the pipe below the trap ALSO has to be provided somewhere to be pushed effortlessly OUT of the waters path into.

The air will fight like h*ll to always rise above any fluids trying to coax it downward, like a string of ping-pong balls in a pipe with enough buoyancy water flow can't simply 'piston' them out of the way or down the line.

Any sizable quantity of water entering a closed-circuit pipe will have to compress, interfere with, the air trapped in that ventless pipe at some point. It might be seen as a bubble trapped in an elbow or vertical section that gets caught by turbulence to cut the true water flow rate by 60-80% as in the 1-1/2" pipe suddenly has an effective diameter of 3/4" or less...

How about calling their 1-877-787-8833 number they displayed on that tech guide PDF?

[timzog]

Originally Posted by Wabbiteer

Gosh it would be easy to say you're absolutely right, lets launch and do it the easiest way . I'm looking at a 32-gallon 'shallow' tank and am pondering a grey water only plumbing system for my project & that option of ventless tie-ins to the main drain line sure is tempting.

Anyhow, a man'f selectively displaying certain design characteristics purely as benefits always makes me a little suspicious.

If it seals so perfectly to not allow ANY stack gas to back-flow and permeate the living area, then filling the GW tank will pressurize the shower drain tube and put hydrostatic pressure on the bladder. Sure, they show 'high' static back-pressure videos but do they show it passing fluids in normal installations when there is also some back-pressure built up?

How well does that bladder valve work when there is 6" water column (0.25psi) pressure against the discharge side? Does it require 6" of water column on the inlet side to overcome the higher-than-ambient (non-equalized) atmospheric pressure?



One thing I see is maybe the hepvo already restricts the flow enough ("offering a minimal resistance to flow") that trapped air or suds foam will not impede the metered (reduced) flow rate.

In the design we're looking at, draining directly into a pool of standing water, is not an acceptable practice. Usually the air in the pipe below the trap ALSO has to be provided somewhere to be pushed effortlessly OUT of the waters path into.

The air will fight like h*ll to always rise above any fluids trying to coax it downward, like a string of ping-pong balls in a pipe with enough buoyancy water flow can't simply 'piston' them out of the way or down the line.

Any sizable quantity of water entering a closed-circuit pipe will have to compress, interfere with, the air trapped in that ventless pipe at some point. It might be seen as a bubble trapped in an elbow or vertical section that gets caught by turbulence to cut the true water flow rate by 60-80% as in the 1-1/2" pipe suddenly has an effective diameter of 3/4" or less...

How about calling their 1-877-787-8833 number they displayed on that tech guide PDF?

If the Hepvo valve is above the grey tank and the grey tank is vented, I don't see how there will be any hydrostatic pressure on the back of the Hepvo except maybe from sloshing around. I am trying to get my head around the air bubble concept. I see that there is a difference between flowing into the top of the tank where it can just drop in and having to flow through the bottom, but my gut tells me it will be effective with a 1 1/2" drain pipe. I'm planning on mocking something up tomorrow and I'll take some pictures and post.