Build thread for the 72 GMC, finally. Thanks John!

That looks great!

I'm really looking forward to 3 coats of 2K and sanding this stuff. When the epoxy was wet I could see some surface defects, but honestly it's all pretty good. A combination of poor skill and dark meant that there were some runs and sags, but overall it was all pretty good, even the roof through all of those seams. I was thinking as I did it that I had reskinned the roof, and also sliced through both B pillars to improve the panel gaps. I remembered welding air using drill bits to space out the panel gaps as I clamped to the door. And now it all looks very good. If you didn't know this style of truck very well, you'd never notice the shaved drip rails, the improved countor of the A pillar to roof junction, the welded seam at the back of the roof, the missing fuel filler, the custom hood front, and everything else. I'm pretty happy with it!

Dusterbd13-michael said:

That looks great!

Thanks!

Takes about an hour to get here. Now to go over it all with 400 and see if I can get it in 2k. 

That one close up is a modification I did to the hanger so I can mount the fenders and doors at the same time. 

I had a super weird issue during this session. I was using the new 2.0 tip and the regular spi 2k primer. I mixed the primer well, then mixed the batches of primer and activator. Each mix was 30 seconds long. I used the entire first gallon and the entire first quart of activator, so I presume I mixed correctly. 

After 3/4 of the primer was gone I was going slow. It looked dry and the pattern felt narrow. I was adjusting the gun and not happy with it at all. The compressor was struggling, but I was still over 40 psi at the gun. I finally looked at the tip and saw primer build up through the outer discharge holes and at the tip itself. It was like looking at stalactites. I wiped it off, then it was ok for a bit, then the started again. 

Why!!??

I was running a dryer in front of the gun. I strained every batch as I poured. I can't imagine what I did wrong. 

tuna55 said:

I had a super weird issue during this session. I was using the new 2.0 tip and the regular spi 2k primer. I mixed the primer well, then mixed the batches of primer and activator. Each mix was 30 seconds long. I used the entire first gallon and the entire first quart of activator, so I presume I mixed correctly. 

 

After 3/4 of the primer was gone I was going slow. It looked dry and the pattern felt narrow. I was adjusting the gun and not happy with it at all. The compressor was struggling, but I was still over 40 psi at the gun. I finally looked at the tip and saw primer build up through the outer discharge holes and at the tip itself. It was like looking at stalactites. I wiped it off, then it was ok for a bit, then the started again. 

 

Why!!??

 

I was running a dryer in front of the gun. I strained every batch as I poured. I can't imagine what I did wrong. 

Any ideas on this? There's a (slight) chance of me getting another short session of 2K next weekend for the backside of some things.

Not sure what the pot time of the 2k is for your product. 

When I was doing the high build featherfill I had a similar issue. Turns out that I mixed a big batch and the exothermic nature of the product created a runaway heat cycle and product was starting to go off in the gun.

The solution was to mix smaller batches and I ran some cleaner through the gun between rounds of freshly mixed primer.

I sprayed Slick Sand for high build on my '61.  It has a pot life of something like 12 or 15 minutes.  Except I was spraying outside, and with the temperature, it was curing in the gun in 7 minutes.  I had to freakin' BOOGEY.  And ONLY mix the amount I could spray.  And I was using a 2.3 tip!

Having said that, after sanding I ended up with some of the best looking bodywork I had ever done.

Nice, thanks for a consensus there. I did indeed mix two batches into one to save myself from stopping. That's likely it.

At any rate, like is said above, the primer looks fantastic.

I got home from a busy business trip, ready to jump in to a flurry of pent up kids activities and laundry and mess. We had three things scheduled for Saturday and so many things. 

But a couple of kids have covid. 

So we're not going anywhere. 

So I can prime and sand today. 

In reply to tuna55 :

 Booooo! For sick kids.

Yaaaaay! For truck progress.

I haven't posted in here in years but I'm so stoked for you being at this stage!

First round of sanding is very promising. The worst spot is behind the fuel filler patch, but you can't even really see it. 

I found three tiny shallow spots on a door. Two tiny shallow spots on the gate, and generally that was it save some minor voids. It's all down to 400 grit now and I have another sanding session to do before I do the second coat of 2k. I think I'm on track for body color I can be proud of in the spring. 

Going to be a long winter waiting for the color!

In reply to NOHOME :

Tell me about it. I don't think I have enough time or weather, but this way it'll be absolutely ready for a seal coat and color. 

chandler said:

I haven't posted in here in years but I'm so stoked for you being at this stage!

Thanks dude!

NOHOME said:

Going to be a long winter waiting for the color!

It just gives more time to get the air ride suspension finished.

Well that's the last coat of 2k primer. Wow. I did normal sized batches and cleaned the tip after every batch and that was very helpful. I managed to clean off everything I was remotely worried about before beginning, but I finished just minutes ago in the dark with a headlight. No pictures. It's good. 

SkinnyG (Forum Supporter) said:

NOHOME said:

Going to be a long winter waiting for the color!

It just gives more time to get the air ride suspension finished.

Rewind like five years to when I re-engineered the entire suspension. 

Ok.  I went back and skimmed through 2017-2019.

I kept seeing coil springs.

Looks like you're all set for the air ride conversion! (grin)