Which steel?

Alexjpx · 07-12-2018, 08:11 PM

So all the windows are out and I'm putting in sheet metal. 2 questions.

1. Which gauge steel? I was thinking 18

2. Galvanized or not? I was reading that painting galvanized steel was tricky. I was going to paint the bus with some type of enamel but read it isn't the best for galvanized.
thoughts? Thanks

EastCoastCB · 07-12-2018, 09:51 PM

Quote:

Originally Posted by Alexjpx

So all the windows are out and I'm putting in sheet metal. 2 questions.

1. Which gauge steel? I was thinking 18

2. Galvanized or not? I was reading that painting galvanized steel was tricky. I was going to paint the bus with some type of enamel but read it isn't the best for galvanized.
thoughts? Thanks

18ga is what I use. Its perfect for the job.
I just buy regular hot rolled 18, but recently got 3 sheets of cold rolled for the same price and hot rolled.

o1marc · 07-12-2018, 10:19 PM

Quote:

Originally Posted by EastCoastCB

18ga is what I use. Its perfect for the job.
I just buy regular hot rolled 18, but recently got 3 sheets of cold rolled for the same price and hot rolled.

I meant to ask you what the going rate was down there for 18g? Not your buddy deal, but going rate. My salvage yard here wants $75 for a 4'x10' sheet of 18g.

Tango · 07-12-2018, 10:26 PM

18g is probably ok as long as you use smaller sheets...like one piece per window. Most bus bodies are around 16g and some fab their metal to odd specs. BB is more like 15g.

As for galvanized, unless you go with Galvalume which is prepped and ready for painting, it can be tricky. Paint will not adhere to galvanized (or aluminum) unless it is properly etched first. Cold rolled steel is much easier to work with and can be welded easily if needed. Galvanized can be quite toxic to weld.

EastCoastCB · 07-13-2018, 05:18 AM

Quote:

Originally Posted by Tango

18g is probably ok as long as you use smaller sheets...like one piece per window. Most bus bodies are around 16g and some fab their metal to odd specs. BB is more like 15g.

As for galvanized, unless you go with Galvalume which is prepped and ready for painting, it can be tricky. Paint will not adhere to galvanized (or aluminum) unless it is properly etched first. Cold rolled steel is much easier to work with and can be welded easily if needed. Galvanized can be quite toxic to weld.

I have to disagree.
16ga would be overkill for skinning over windows and roof hatches.
I've used 16, 18 and 20 and 18 is definitely the sweet spot for bus skinning.

YMMV of course.

thrifty1 · 07-13-2018, 07:51 AM

My ceiling metal was 19 gauge, and that’s what I used to skin probably 12 windows. Saved lots of money on it as well. You can see the results on my thread thing. Now that I have spray foamed and sealed it all it feels solid as a rock.

Tango · 07-13-2018, 08:56 AM

I'm just sayin' the "ideal" is to try and match as closely as possible whatever is on the rig. But if that's not possible, going up one gauge will help reduce the possibility of oil canning if properly installed.

EastCoastCB · 07-13-2018, 11:11 AM

Quote:

Originally Posted by thrifty1

My ceiling metal was 19 gauge, and that’s what I used to skin probably 12 windows. Saved lots of money on it as well. You can see the results on my thread thing. Now that I have spray foamed and sealed it all it feels solid as a rock.

Where did you find 19ga??

EastCoastCB · 07-13-2018, 11:11 AM

Quote:

Originally Posted by Tango

I'm just sayin' the "ideal" is to try and match as closely as possible whatever is on the rig. But if that's not possible, going up one gauge will help reduce the possibility of oil canning if properly installed.

18 is a little thicker than the buses I've patched up.

thrifty1 · 07-13-2018, 11:14 AM

When I pulled the calipers on my ceiling metal material it was thinner than 18 gauge, and thicker than 20. No joke lol

EastCoastCB · 07-13-2018, 11:55 AM

Quote:

Originally Posted by thrifty1

When I pulled the calipers on my ceiling metal material it was thinner than 18 gauge, and thicker than 20. No joke lol

Then that would be 19ga.

I've never seen those odd gauges for sale, and I worked in steel for over a decade. Not saying they aren't out there, but they're probably hard to find and very expensive. 18ga can even be a little tough to find. The bus manufacturers must have ordered their odd gauges special.
I called around central FL and all I could find in 18ga was in Orlando and they only had it in 4x8's of cold rolled for $110 each and they only had a couple. I ordered some 18 ga from a supplier through my step dad who works with steel and got 3 4x10's for $160! That's hot rolled.
Saw the prices going up so I ordered 3 more in cold rolled and got em for $180.

EastCoastCB · 07-13-2018, 11:56 AM

Quote:

Originally Posted by thrifty1

When I pulled the calipers on my ceiling metal material it was thinner than 18 gauge, and thicker than 20. No joke lol

Oooooooh, I see! You used your old ceiling metal for skinning!

I thought you'd went and bought 19ga somewhere. Derrrp!

thrifty1 · 07-13-2018, 12:44 PM

Haha nope just repurposed. I did have to buy a sheet of 18 gauge around here and paid 89.34 for a 4x10 cold rolled sheet though.

Tango · 07-13-2018, 11:10 PM

Seems a number of Skoolie makers spec their own (oddball) sheetmetal. And you are right...no one sells a match.

brokedown · 07-14-2018, 07:51 AM

I used ceiling panel metal for the windows I deleted. I decided that deleting windows was more work than it was worth after doing just 4 of them though. I'm going to use more of the ceiling metal (and chair metal) as I go, I plan on having very little scrap when I'm done!

Jolly Roger bus 223 · 07-14-2018, 01:21 PM

My 86 Thomas is all 15-gauge ?
but anyway?
Galvanized will hold a regular paint if you wipe it down good with plain old white vinegar.
That cleans the coating off of the galvanizing and opens its pores so have the paint ready as soon as the vinegar dries especially on a hot day.
And if using full sheets I might could recommend(depending on cutting on bending methods) cleaning and painting the full sheet and then it's just touch ups.
A primer paint on especially cold roll is must have base.
I ain't a painter and never want to be but have been around sheetmetal,sheet steel, and steel for a while and I know that vinegar will save the cost of self-etching primer/paint on galvanized

EastCoastCB · 07-14-2018, 02:13 PM

Quote:

Originally Posted by Jolly Roger bus 223

My 86 Thomas is all 15-gauge ?
but anyway?
Galvanized will hold a regular paint if you wipe it down good with plain old white vinegar.
That cleans the coating off of the galvanizing and opens its pores so have the paint ready as soon as the vinegar dries especially on a hot day.
And if using full sheets I might could recommend(depending on cutting on bending methods) cleaning and painting the full sheet and then it's just touch ups.
A primer paint on especially cold roll is must have base.
I ain't a painter and never want to be but have been around sheetmetal,sheet steel, and steel for a while and I know that vinegar will save the cost of self-etching primer/paint on galvanized

The Thomas I've got of Kubla's is 18/19.

Got a pic of that 15ga skin? I've seen the ribs in 15, but 15ga skin would be massive overkill.

Tango · 07-14-2018, 05:40 PM

No pix but that is what my old ('78?) BBAA miked out to. I used 16 to fill in the gaps when I did my roof raise. Not really that much difference between the two. Just impossible to match.

mikeypj · 07-14-2018, 08:00 PM

Quote:

Originally Posted by thrifty1

My ceiling metal was 19 gauge, and that’s what I used to skin probably 12 windows. Saved lots of money on it as well. You can see the results on my thread thing. Now that I have spray foamed and sealed it all it feels solid as a rock.

So did you reuse any of the sheet metal removed from the bus on the windows?

thrifty1 · 07-14-2018, 08:12 PM

All I used was the ceiling metal for skinning the windows. The inner panels were galvanized or something and hard to work with. I just plasma cut them out and trashed em.

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