Great Stuff?

[family wagon]

Originally Posted by maggiemae

We really appreciate your insight.
Did you still use the same method... The one posted earlier with the air hammer and modified chisel?
How many chisels did you go through with the ceiling?

Yeah, same method. On my thread there's a little mention about using a pin punch in the air chisel for popping the mandrels out of the rivets, too. But I only did two ribs with the chisel before pulling out the plasma cutter to test how much mess it would make. No chisels were harmed because I changed methods... but I did start a small fire on the floor with the shower of burning metal from the plasma cutter. Oops.

[taskswap]

Did you pop out the mandrel first or just try to chisel straight through the whole thing?

[family wagon]

Originally Posted by taskswap

Did you pop out the mandrel first or just try to chisel straight through the whole thing?

The walls down low by the chair rail had some small rivets, 1/8" maybe, which I just went after as-is. They were small, aluminum, and come to think of it the mandrels were usually broken off pretty deep too. But for the larger aluminum rivets on the wall, and for the steel rivets on the ceiling, the mandrels were usually broken very near the surface of the head. I popped those mandrels out through the back before chiseling the heads off. It's amazing how much difference it makes. It made a notable difference even when plasma cutting instead of chiseling the heads off, too.

[taskswap]

Is this a suitable technique for exterior panels you plan to re-use, or does the chiseling damage the holes/surface? I was planning to drill those but this is starting to sound like a good excuse to get a new tool. ;)

[family wagon]

Originally Posted by taskswap

Is this a suitable technique for exterior panels you plan to re-use, or does the chiseling damage the holes/surface? I was planning to drill those but this is starting to sound like a good excuse to get a new tool. ;)

It's pretty rough. The chisel will definitely scratch and mar the surface, but has a good chance of denting or even cutting into the panel. I'm going to re-use my rub rails and my roof, so those rivets are getting the drill treatment. For that I've been drilling to where the head is nearly severed from the shank, then putting the pointed chisel (or drift? ) into the hole. It finishes breaking the head from the shank and (sometimes faster, sometimes slower) pops the shank out the back side of the hole. But it's hard to control; often it bounces out and pecks at the surrounding metal which I'm not so happy about.

[jazty]

Originally Posted by taskswap

Is this a suitable technique for exterior panels you plan to re-use, or does the chiseling damage the holes/surface? I was planning to drill those but this is starting to sound like a good excuse to get a new tool. ;)

Another method for removing blind rivets is to use a flap-disc on an angle grinder. I have removed many blind rivets this way when I wanted to preserve the metal. It removes paint or course, but if you plan on painting anyway it isn't a problem. Just be careful not to dig too deep.

[nat_ster]

I use my 1 inch hand chisel with hand guard and 2.5 pound hammer to remove the rivets without damaging the panels. The hand approach gives more control than the air chisel.

Some of my rub rails had the rivets dimpled into a indent, preventing the chisel from getting under the edge of the rivet. Like others, I drilled out the center, then used the chisel to remove the head.

I have also used the flap wheel. It worked good, but I prefer to use methods that don't use expensive consumables like drill bits and flap wheels.

Nat

[HolyBus]

Interesting. Another one of my messages deleted from a thread.

[nat_ster]

Originally Posted by HolyBus

Interesting. Another one of my messages deleted from a thread.

I better start watching for that too. thx

Nat

[maggiemae]

Yaay we took the first panel down yesterday! Justin used the grinder for the dome headed rivets and a drill for the hollow ones! Thanks for all your help!
The panel is still in great shape! We left one side on but have full access to the needstobeinsullated space. We also finished painting the outside!

[EastCoastCB]

Yeah the rivets are maddening. Congrats on getting them out. It really is for the best. When my friends showed up to help, they all tried like hell to convince me that the metal panels needed to stay. This was due to the sheer amount of work.
I knew better though.

[maggiemae]

Originally Posted by EastCoastCB

Yeah the rivets are maddening. Congrats on getting them out. It really is for the best. When my friends showed up to help, they all tried like hell to convince me that the metal panels needed to stay. This was due to the sheer amount of work.
I knew better though.

Totally agree. Lots and lots of work though. I think if there was any insulation at all up there like many other busses have, we would have just left it.

Now we have to decide on what kind of insulation. Panels have the best r value, but aren't curved. Rigid closed cell foam is costly, and we are not going to remove that black stuff.
Also has anyone put a bit of insulation in between the beams and the inner metal ceiling? Maybe some tar paper?

[EastCoastCB]

Tar paper would be worthless. Fiberglass is next to useless.
You need foam board, scored on one side and bent into place where necessary. Great stuff around the edges, and you'll have decent insulation. For the kind of winters you folks have out there, I'd really want to put a lot of deliberate thought and effort into insulating.
I plan to drive my bus out there to live and am building accordingly.

You don't have to take out the tarry stuff. I have to, but I'm glad its coming out. If my hatches hadn't leaked their entire lives I'd be leaving mine most likely. Getting rid of it has so far been the hardest work I have done on my bus. Makes the rivets look fun.

[family wagon]

Originally Posted by maggiemae

Also has anyone put a bit of insulation in between the beams and the inner metal ceiling? Maybe some tar paper?

EastCoastCB has you covered for the gaps between the ribs, but you're also looking for something to reduce heat transfer between the steel sheet and the ribs. You'll be re-installing a fastener like a rivet or screw in all the holes, I guess, and you want to build a sandwich to reduce the conduction there?

There's a fun list of Thermal Conductivity of some common Materials and Gases at Engineering Toolbox for ideas. Apples, for example, at 0.39 Watts per meter. Smaller numbers are less conductive, ie better insulators. The chart has a line for "insulation materials: 0.035-0.16." I guess, according to somebody's definition, an "insulator" has conductivity less than or equal to 0.16 W/m (so apples aren't really an insulator). Polystyrene and polyurethane foams are shown at 0.03 and fiberglass at 0.04, so that's a reference point to think about. Paper is down there too at 0.05 and felt at 0.04. But for a sandwich application like this all these may be poor choices because they'll compress easily when you tighten the fasteners (and over the years).

There's no getting around the fact that the thickness of the layer matters. Rubber such as truck mud flaps (is that natural rubber?) comes in at 0.13; teflon at 0.25 would have to be twice as thick as the rubber to get the same level of thermal conductivity.

Things on the chart that looked interesting to me: acrylic (Plexiglas), hardboard (Masonite), cotton (as denim perhaps?), various kinds of woods, cork, other kinds of plastic sheet. Some of those are maybe not so ideal because they'll degrade if (when) they get wet. Some of these materials are pretty thin and might require several layers (ie the denim). Sign-making shops (or their distributor) are a good place to get a wide variety of plastics in sheet form. Since you'll only need narrow strips, you might be able to get a good deal on their scraps rather than slicing a whole sheet.

[HolyBus]

Are you refering to putting tar paper where the ceiling panels rivet back on? So the rivet goes through the ceiling panels then the tar paper then the framing? Not a bad idea.

[nat_ster]

Like mentioned, you all need to remember the condensation up there.
Putting silly things like tar paper up there just gives more to hold that moisture and cause mold, ect.

Also dont forget the heat. Things like rubber, tar paper ect in a non vented living space heat up, break down, and stink. That stink is the product giving off gasses that are not safe for humans.

Vaulting the lifted ceiling makes insulating so easy. Also finishing the ceiling will be easy also. Trying to do anything with curves takes a ton of time, and leads to poor installs/ performance of the product. Flat surfaces are the way to go.

My vaulted ceiling is a perfect 4 feet on each side. This was important to make full use of 4x8 sheets of rigid Styrofoam and FRP.

This would be the same for paneling, arborite, or any other covering that comes in full 4x8 sheets.

Hard to beat a good roof raise. ;)

Nat

[maggiemae]

Eastcoast, you're right about the paneling, it seems like our best bet. I know spray foam is good too... But paneling will be easier and more efficient, you're right!

Familywagon, that's so interesting! Maybe I should just insullate my ceiling with apples, lol. It'd smell lovely for about a day!

Holybus,
Yes I'm thinking about something that I can 'sandwich' in there. Tar paper strips seemed like a good option. My thoughts are: it's thin enough to go in between the beams and inner metal, it's uses are on roofs where it gets hot and wet, and also under bathroom floors, where it gets hot and wet. This leads me to think that (and correct me if I'm wrong) it's application as a "sandwich" between that tiny space will be ideal, stopping some of that metal on metal bridging. Tar paper is meant to not absorb water, and be able to be long-lasting in hot conditions (like on a roof), right?

Nat, the tar paper wouldn't be on the inside of our living space, it would be inside the ceiling. Also, I'm not sure that we can do a roof raise. I just worry about the structural integrity of the bus, and the time it takes (we only have 15 weeks left on this build). A raised roof would be nice as far as vertical space goes... it's just not for us, the cons far outweigh the pros for our build.


Ooh, also... We still have the rubber floor reminants that we tore out. Maybe those could work?

It's really not a huge issue to find some sandwich material. I was just trying to brainstorm and see what y'all thought!

[maggiemae]

Oh! I forgot to say,
Family wagon, that is a great idea about the sign shops and their plastic reminants! I will have to call around tomorrow! Plastic would definitely be the way to go if the price is right. The only thing is finding the right price . Also, making sure we get plastic that can handle high temperatures.
Thanks!!

[EastCoastCB]

https://www.youtube.com/watch?v=wIjxASydhR4

This video build does a good job of showing what I'm talking about.

[jazty]

Originally Posted by maggiemae

Oh! I forgot to say,
Family wagon, that is a great idea about the sign shops and their plastic reminants! I will have to call around tomorrow! Plastic would definitely be the way to go if the price is right. The only thing is finding the right price . Also, making sure we get plastic that can handle high temperatures.
Thanks!!

One more thing to be aware of.
If you space the metal panels 1/8" away from the metal beams using plastic or the like you will find that many of the screw/rivet holes on the curve don't line up any more. You can probably enlarge the holes in the panel to make it work, though.