1968 GMC

I can't take credit for the stand/door mount attachment idea. I saw it in a build thread on the 67-72 forum. I'm not creative enough to think of these things!
 
I got the inside of the cab seam sealed and epoxied the rest of the cab last night. I forgot how strenuous it is to do yoga inside the cab in order to get underneath all of the dash area without touching the floor too much.

I'm excited to start filler work. I know that sounds crazy but it's not that I like doing filler work, but that it means I've reached a milestone and that it's progressing.

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I spent a couple hours just spreading mud last night, probably 15 batches. I have my work cut out for me. Clean Sheets are awesome, I just wish I didn't have to clean the spreader off every time.

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I spent a couple hours just spreading mud last night, probably 15 batches. I have my work cut out for me. Clean Sheets are awesome, I just wish I didn't have to clean the spreader off every time.
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Don't clean your spreader every time. Pick up about 6 spreaders. They are to cheap to worry about the cost. Get yourself a metal coffee can or something similar and put about 3 inches of lacquer thinner in it. When you finish spreading your filler, toss the spreader in the coffee can and retrieve the one that is on the bottom. Wipe it clean with a shop towel and do your next batch. Your spreaders will last forever and you will always have a nice clean one to use. The lacquer thinner will keep the filler from hardening and will soften it just enough, you can wipe the spreader clean.

John
 
This is what 5 hours of sanding looks like. I've got almost all of my first round of filler sanded down. I got sick of sanding the other day and decided to work on brake lines for a bit and then got stumped so I'm stalled on that too. It felt weird applying bondo to unsanded epoxy, but as promised it bit into the epoxy (within the 7 day window) and feathered out just fine.

It's a little harder to find time to work on it nowadays with my fiancee taking classes and a new puppy at home, but we're figuring it out. My dreams of having the cab, doors, and fenders painted before winter aren't realistic anymore so I'm just working to get the cab painted. Sometimes life gets in the way of our hobbies and that's okay. I'll just be happy when the cab is done as it is by far the biggest chunk of bodywork.

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They are alot of work. No harm in just getting the cab done, you can build alot of the truck with just the cab and core support done.
 
Not great pictures, but just a quick update. I've been sanding on the cab every chance I get and I think I'm finally done with filler. I'm taking tomorrow off so I can finish prepping the cab, doors, and fenders fo a coat of epoxy so that I can shoot some high build on Thursday and block sand on Saturday. I'm on a mission to have these parts turned blue by the end of the month.

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Looks great! Just a suggestion: If you are going to be taking this truck to shows, with the hood open, I would make the passenger side of the firewall match the driver's side. Fill in the arc where the firewall went around the heater fan. I didn't on mine, and I'm sorry every time I open the hood. Again, just a suggestion.
 
I got everything done yesterday that I wanted to. Theoretically, filler work on the cab, doors, fenders, and cowl should be done. I sprayed one coat of unreduced epoxy over everything and I'm mostly happy with it, but 80 grit scratches are my nemesis. I knew that the filler spots would flash, but I still see a lot of sand scratches. I start with 80 to level and feather then 180, but it looks like the 80 left some deep scratches in the metal. Will two coats of high build and sanding of those coats fill those scratches? Also, should I sand out the cratering prior to shooting high build? Or can I shoot high build over the craters and sand the high build without issue? The last picture shows scratches and cratering. The seam sealer came out pretty well though.

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My opinion only.

One coat of epoxy was not enough. If you can before your seven day window passes put 2-3 more coats of epoxy on it and block with 180 or 220. It will fill those scratches. From there you can decide whether you need 2k or whether Epoxy alone will do it.

Also, nothing will fill scratches until you sand it. Never expect the scratches to dissappear when the primer is first sprayed.

John
 
I was planning on shooting high build tomorrow, is there an advantage of epoxy rather than high build for this particular situation? I have plenty of both.
 
I was planning on shooting high build tomorrow, is there an advantage of epoxy rather than high build for this particular situation? I have plenty of both.

Wow. That is a bit of a loaded question. For me, a hobbyist with lots of time, I like to use the epoxy as much as I can. It is less prone to chipping, has better adhesion and less shrinkage. It can be recoated out of the same batch for several days and I don't have to clean the gun every 30 minutes. Only SPI can be used this way because it is the only epoxy I know of that will build, but when possible, I use nothing but SPI epoxy and body filler from metal to paint.

The guys who do production work will probably give you a different answer but to them time is money.

John
 
I hear ya. I will probably use the high build since I have it and put on two coats tomorrow. Will 320 followed by 600 over that be enough to get rid of the scratches?
 
I hear ya. I will probably use the high build since I have it and put on two coats tomorrow. Will 320 followed by 600 over that be enough to get rid of the scratches?

Block your high build with a minimum of 180 on the first round of sanding. Use guide coat to see if you are flat. Only after you have everything blocked flat do you want to be moving up to 320.

Since your going over some good scratches it would be best to spray your high build and let it sit for a few days, maybe even put it on the sun to eliminate any shrinkage you might see before you sand.
 
Just for future reference, I like to put at least 2 coats of epoxy under the 2K for a couple reasons. First is the extra corrosion protection it provides, and second is as you are blocking the 2K you will inevitably go through to the epoxy in places. If there is only 1 coat metal will appear real quick. With 2 or more coats, you have a little more room for error. If you do hit metal you must spray epoxy over that spot anyway, ,then wait overnight, so you're not saving any time. High build 2K has quite a bit of wave to it, and starting with 320 will not get it out (ask me how I know). Start with 180 minimum, even though I have been starting lately with 120 with good results. If I were you, I would go ahead and sand it lightly with 180 then spray 2 more coats of epoxy tomorrow, with an hour in between. Wait and spray your 2K the next day. I think you will be ahead in the long run.
 
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Tomorrow will be 48 hours, is the 180 required to recoat with more epoxy?

And how long do you have to wait to spray 2K? The tech manual doesn't address 2K, just polyester.
 
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