Roof Raise Confusion

[EastCoastCB]

Originally Posted by Rusty

Yes, OxyAcetylene torch is for cutting metal, but the business end of a TIG is also called a torch, on a MIG it's a gun 'cuz stuff (wire) comes out.

Precisely.

[Drop out]

Ok, I've got stuff in Nuclear research facilities. I've done bridges but smaller.

I'm not certified, I never needed it, the bridges were private and the research stuff, they didn't know how to certify that.

I've done less heavy iron than small stuff, that's one of the reasons why I like TIG.

I don't think I'll get in to hobby bridges any time soon so I like welders that are good for small stuff and maybe the occasional 3/8" or 1/2" plate. A 300 amp TIG welder can do all that and aluminum, copper, silicon bronze brazing, Titanium, etc.

Oh, a TIG welder has a torch too but it doesn't cut anything.

I've grown fond of plasma cutters for cutting. Oxy-atcetaleyne is more versatile but a lot more fuss. If you can only rough cut with a torch, you're not doing it right.

[EastCoastCB]

Originally Posted by Drop out

Ok, I've got stuff in Nuclear research facilities. I've done bridges but smaller.

I'm not certified, I never needed it, the bridges were private and the research stuff, they didn't know how to certify that.

I've done less heavy iron than small stuff, that's one of the reasons why I like TIG.

I don't think I'll get in to hobby bridges any time soon so I like welders that are good for small stuff and maybe the occasional 3/8" or 1/2" plate. A 300 amp TIG welder can do all that and aluminum, copper, silicon bronze brazing, Titanium, etc.

Oh, a TIG welder has a torch too but it doesn't cut anything.

I've grown fond of plasma cutters for cutting. Oxy-atcetaleyne is more versatile but a lot more fuss. If you can only rough cut with a torch, you're not doing it right.

No reason to get all egotistical about this stuff.
By rough cut, I mean that because I'm used to running Komatsu CNC plasma tables and such.

[Drop out]

Yeah, I was thinking whip but that's not right. My guns are a lot more fun than MIG welding so I didn't think of that.

[EastCoastCB]

The Twister table I used to run could cut SO FINE it was ridiculous. I miss that machine a lot, but I'm way happier NOT working in that shop.

[Drop out]

Did I hit your leg? Sorry.

[Tango]

Just a side note...nearly everyone I know that bought a cheap-o non-gas shielded mig wound up selling it pretty quickly and getting a better gas shielded version. Once you get any welder, you will find a kajillion uses for it and want to get serious. The smoke and spatter of the non-gas units gets old really fast.

Me... I LOVE both of my Millers! Worth every penny.

[EastCoastCB]

Originally Posted by Drop out

Did I hit your leg? Sorry.

Dude- seriously?
I don't even know why you're going on with this. I'm not here to argue or have a pissing contest.

[Drop out]

You pulled out the nukes and bridges first, after you misquoted me. A career in welding should have given you a bit thicker skin. Shops have pissing contests all the time, no one gets away clean.

I apologized, you should take it.

[family wagon]

Originally Posted by Tango

Just a side note...nearly everyone I know that bought a cheap-o non-gas shielded mig wound up selling it pretty quickly and getting a better gas shielded version. Once you get any welder, you will find a kajillion uses for it and want to get serious. The smoke and spatter of the non-gas units gets old really fast.

I bought my first (and so far, only) welder a little over 15 years ago and had only a few weeks' training through an evening adult community education class at a nearby vocational school. It's the "bottom-of-the-line" 240 volt Miller MIG, meaning "the smallest one they made that's still 240 volt." It was hard to pony up the cash, but just as you say, I've found a kajillion uses for it. It has more than paid for itself by enabling me to repair things that had to be repaired -- not to mention the countless "optional" things I've been able to do because I have a welder sitting around. My first sign of what was to come was when the door skin around the latch mechanism in my '95 Grand Cherokee tore out just a few weeks after I'd bought the welder. When one considers the alternatives (buy a door from a junk yard and probably have to paint it to match, or have a body shop make repairs) I probably justified the welder on that first repair alone.

[Drop out]

Yep, that's a common story and the step from 115 to 220 is a big one.

The regrets come in stories about flux core and 115v.

I've never bought a 115v flux core welder but I had to use one once (on a piece that was too heavy to move and too far from the 220) and I got so pissed off I think I broke my hand breaking off the shitty weld it made.

You could say that means a shitty flux core weld is stronger than my hand but I just say I'm never using a 115v wire feed again.

[EastCoastCB]

No regrets here, my roof is solid as can be, and it was done with 115 and flux core.
I'd love a bigger better welder but this little sucker was cheap and its very handy. I do plan to eventually get a bottle of gas for it, but they're expensive and I've been patiently waiting for a freebie.
If you ever find yourself in FL come by and try it. Seriously!

[Asetechrail]

My little 115v Lincoln will weld with gas or flux core. When using flux core you need to reverse the polarity. It is a lot easier to get nice welds with gas but most of my work has been with the flux core. When you are working outside in windy conditions the gas is about useless. I don't have a nice shop to work in so flux core has been very handy.

[The Rockwood Colony]

Originally Posted by Drop out

If you just want to weld hat channel together, I would suggest a pop rivet through the top of the hat because the cost will be minimal.

Rivets alone would be fine, rivets glue and welding is very redundant.

If you don't want to buy a quality machine I suggest eliminating the weld. That will work for your budget and you don't have to learn welding.

If a Hobart is too expensive for you, stop.

You can buy a quality used welder and sell it when you are done if you can't afford to keep a welder but not buying a welder is lots cheaper than that and no risk.

Speaking of risk, improper welding can weaken metal so jumping in to welding is a risk.

Learning and a cheap machine is not a recipe for good welds (this goes for flux core, MIG and TIG).

I agree that it could be redundant to adhere, rivet, and weld the hat together but I was told by a few friends that weld that welding would add strength so that is the only reason I was even considering it. I will say that I do have to weld in a couple spots I think unless anyone has any other suggestions. The transition on the roof that goes from the original roof height to the 21" higher roof height will need some sort of supports on that angle like square tubing. Is there a way that i could rivet and adhere that part of the structure together too? AND the back of the bus above the door is where i am popping all of the rivets out to raise so I will need to extend the supports back there but they don't look like the hat channel I had made so I was thinking I would just have to use square tubing to extend them once again and weld it unless someone has a better idea. I have to say though that I'm not 100% sure how to assemble everything in an order where the adhesive cures while being clamped and everything being installed the proper way. This is the order I was kind of thinking:

1. support bus roof
2. cut hat channels
3. raise roof
4. figure out a good drill spacing for the new hat channel and predrill all of them.
5. apply adhesive (which only gives you an hour to an hour and a half to work with it before it sets) like jelly on a sandwich and lap the new and old hats and line up the predrilled holes.

And that is where I'm stuck currently without welding because this adhesive needs clamping power while it cures. Well I can't lap the hats all the way around the bus, and then continue to support the roof while I install all of the sheet metal with rivets all the way around the bus all at the same time. So then I thought, hey I can just clamp the new hat down all the way around the bus and let it cure for a day and then come back, take the clamps off and that should support the roof without the jacks while we start installing the sheet metal (so I've been told) but that freaks me out. Just having glue to hold up the roof while we start installing sheets?!?! Scary. So then I thought, hey, what if I adhered all of these hats together and then on the inside of the "C" part of the hat I bolted the new and old hat channel together for clamping power so then I would get the clamping power and have the extra support from those bolts in the middle of the hat. I could leave the bolts there also permanently. Then the next day I would lay down the other panel adhesive between the new sheet metal and every surface that the sheet metal touches and rivet them on.

I hope that made sense to somebody. My heads spinning just from writing it. I will take any and all suggestions or critiquing! Thanks

[Drop out]

You are over thinking this.

If you want glue (which isn't necessary), just dril a couple holes (through the top of the hat) where your hat channels overlap and pop rivet them together right after you apply the glue. That will do all the clamping you need or you can skip the glue.

The only question in my mind is where is the side panel getting cut and/or moved.

I have never done this but looking at the pictures, I would be tempted to cut half of the hat channels high and half low and make the raise height a multiple of the rivet spacing so the new rivets will be even.

Such a strategy would make the seam a zigzag and let the panel stiffness reinforce the seam.

I might change my mind if the joint detail at the floor or roof of the side looks easy to duplicate.

I might try to get another side (rub?) strip made to hide the seam in the side wall depending on the location of the cut.

Think about how it was made initially, how you could duplicate it with the tools available to you and then how to make what you want with those tools.

You don't want to reinvent the wheel, you just want to copy it and maybe reinforce it a bit.

One other thing to think about is where you can hide any gaps. It would be tempting to start riveting at the corners and work in or start at the middle and work out but doing that might lead to wrinkles. Find a spot at the front or back where you can trim and hide, then give yourself some extra material, start at the other end and trim to fit when you get to the other side.

Things will lay flat and look nice if you keep everything pulled tight when you are drilling and riveting.

Glue might be nice but getting everything held together right while it cures will just complicate everything.

[EastCoastCB]

Originally Posted by Asetechrail

My little 115v Lincoln will weld with gas or flux core. When using flux core you need to reverse the polarity. It is a lot easier to get nice welds with gas but most of my work has been with the flux core. When you are working outside in windy conditions the gas is about useless. I don't have a nice shop to work in so flux core has been very handy.

Yeah same here.

Good example- raising a bus roof in a cow pasture with the breeze blowing and only a 110 outlet available.

[family wagon]

Originally Posted by The Rockwood Colony

So then I thought, hey I can just clamp the new hat down all the way around the bus and let it cure for a day and then come back, take the clamps off and that should support the roof without the jacks while we start installing the sheet metal (so I've been told) but that freaks me out. Just having glue to hold up the roof while we start installing sheets?!?! Scary. So then I thought, hey, what if I adhered all of these hats together and then on the inside of the "C" part of the hat I bolted the new and old hat channel together for clamping power so then I would get the clamping power and have the extra support from those bolts in the middle of the hat. I could leave the bolts there also permanently.

I can understand your discomfort trusting the adhesive that much! The bolts are a fine idea, as are the pop rivets Drop out suggested. A note on pre-drilling: things never work out that well for me on a one-off project like this; the pre-drilled holes would all be just a little off. At most, pre-drill the hole in just one part and drill through the second part after the two parts are aligned in place.

I don't recall how you're planning to do the lifting of the roof. In my case I used scaffold frames with screw jack leveling feet; it was easy to just leave those in place until I had finished securing the hat channels. With the hat channels re-riveted top and bottom and the scaffold removed, mine sat with just the hat channel sticks holding up the roof for over a year before I got the new sheet metal fastened into place.

Originally Posted by Drop out

I might change my mind if the joint detail at the floor or roof of the side looks easy to duplicate.

I might try to get another side (rub?) strip made to hide the seam in the side wall depending on the location of the cut.

I raised my roof by disconnecting all the hat channels at the chair rail at the floor. Most were held by 4 rivets, but some were held about about 20. Part of what both enabled and drove me to do this is that I wanted to re-skin the full side of the bus, so it didn't make any sense to cut the hat channels part-way up. Such a cut does make more sense when one is leaving the lower half of their walls in place.

Rub rail is indeed a nice way of concealing horizontal lap joints in the sheeting.

[Brewerbob]

I need to go back and read this thread in its entirety.

ECCB,
You did a 10" raise you said right? Any idea how much of that 10 you'll lose once you put the ceiling and floor back in? I'm thinking 3" for the ceiling and +2" for the floor.

The ribs on the BB are 2" deep. I'm not going overboard worrying with the thermal bridging of screw/nail heads. I don't think that would make a measurable difference. But I do NOT want the new ceiling to be flush with the ribs with a 1" wide metal bridge x 14 ribs either. So spray or board foam at least 1/2" over those? Maybe a full inch?

Same with the floor. If I spray 1 1/2" deep and then the flooring system itself. Assuming solid wood flooring (don't know that I will go that route), that's 1/2" ~ 3/4" on top of the insulation.

So taking upper end of the above, your 10" raise is now only 5". As I recall, you're going to be chasing the weather so won't need the insulation. But then someone said that CabinBus was said to be hot and he has 3 1/2" under the wood siding?

I want to get quotes for sheet metal and get it bought but I just don't know what width to get. If it's cheaper to buy 48" wide sheets than 36" sheets then I'll do that and cut it myself but if it's the same or cheaper, I'd rather have straight edges.

[EastCoastCB]

Originally Posted by Brewerbob

I need to go back and read this thread in its entirety.

ECCB,
You did a 10" raise you said right? Any idea how much of that 10 you'll lose once you put the ceiling and floor back in? I'm thinking 3" for the ceiling and +2" for the floor.

The ribs on the BB are 2" deep. I'm not going overboard worrying with the thermal bridging of screw/nail heads. I don't think that would make a measurable difference. But I do NOT want the new ceiling to be flush with the ribs with a 1" wide metal bridge x 14 ribs either. So spray or board foam at least 1/2" over those? Maybe a full inch?

Same with the floor. If I spray 1 1/2" deep and then the flooring system itself. Assuming solid wood flooring (don't know that I will go that route), that's 1/2" ~ 3/4" on top of the insulation.

So taking upper end of the above, your 10" raise is now only 5". As I recall, you're going to be chasing the weather so won't need the insulation. But then someone said that CabinBus was said to be hot and he has 3 1/2" under the wood siding?

I want to get quotes for sheet metal and get it bought but I just don't know what width to get. If it's cheaper to buy 48" wide sheets than 36" sheets then I'll do that and cut it myself but if it's the same or cheaper, I'd rather have straight edges.

I'll only be losing 2" on the floor and an inch on the ceiling... So around 7" net raise. Its PLENTY spacious now.
Cabin bus has factory insulation with some fiberglass under the siding. I'll be using foam.

[Brewerbob]

Originally Posted by EastCoastCB

No regrets here, my roof is solid as can be, and it was done with 115 and flux core.
I'd love a bigger better welder but this little sucker was cheap and its very handy. I do plan to eventually get a bottle of gas for it, but they're expensive and I've been patiently waiting for a freebie.
If you ever find yourself in FL come by and try it. Seriously!

I have zero experience with welding but I do have the same Hobart you do. As novice as I am, I say WTF when I try welding and forgot to open the valve on the gas. It's a night and day difference on the bottle. Welding with solid wire and no gas certainly sucks. I do have flux core that came with the welder but I've not used it much.