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Bodywork and Paint Help Needed

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Suppatime
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Bodywork and Paint Help Needed

Post#1 » Mon Jul 02, 2018 6:48 pm

Hello All:

Still trucking along with Puchy. Engine brackets have been fitted and I'll be hitting the underside of the body with some 3M polyurea before mounting it to the chassis... I'll also be doing the bodywork and spraying the truck myself. Hooray projects!

Here's the issue I'm facing though, and I can't find information anywhere. The truck has been media blasted and coated with etching primer... but this was done easily 2 months ago now. I know it won't rust in its current state, but I'm hellbent on painting it in its entirety before I reassemble.

What's the process I need here? I've been looking for products to clean the etching primer with but haven't found any... do I just dry sand with 400 grit, hit it with some canned air, bondo and sand, hit it with air again and paint? I've heard I may just need to hit the whole thing with fresh etching primer first, but can't find any info anywhere.
Project Puchy

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Re: Bodywork and Paint Help Needed

Post#2 » Mon Jul 02, 2018 6:51 pm

Might as well get you guys a little more excited:

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Wolf-y

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I'm aware the engine is sitting too high. Have the correct fan shroud and the whole thing ended up coming down 1.5".

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Gearing up to fit a black 2.5" intercooler.
Project Puchy

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vadimivanovich
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Re: Bodywork and Paint Help Needed

Post#3 » Mon Jul 02, 2018 10:10 pm

If the etching primer was done thoroughly, you should be fine cleaning with soap & water, dry in the sun, and then roughen everything up with 4-600 grit.

Bodywork & filler should be done one panel at a time, with the hood & roof being the hardest to do right. Body filler should ideally be applied in one go, and rough-sanded with 40-grit using a rubber block (as long as possible to help flatten without ripples) while the filler is still soft - like a cheese consistency or slightly stiffer.

Be aware that bondo sets up super fast in the heat, so do that work at night or in the shade, using the minimum hardener permissible. Use a scale to make sure you get the ratio right. Mix thoroughly and quickly!

Body glaze is just a thin version of filler. It works better for shallow ripples because you can spread it over a large area thinly and more evenly. It's an easier filler to work with for many things.

Also be aware that when you apply more than one coat of filler to the same spot, different layers will sand at different rates - the fresher layer will be softer. This can make flatness difficult to achieve. It can help to knock down the high spots when fresh and wait a few days to let the hardness even out for final sanding.

When the filler is done, go over the whole car with slick-sand or feather-fill polyester filler primer. It should be wet-sanded with 400 grit & a short block. This stuff is thick enough to fill sanding scratches that you otherwise would only notice after paint. This coating can be thinned out for use as a sealer too - or use a separate sealer. Only then are you ready for color & clear (or just color for single-stage paint).

Shooting all of this primer will give you practice for the final paint work. Paint is thinner and tends to run more easily, so be careful. A primer gun can have a 1.8 to 2.0 mm spray needle, while the paint gun should be anywhere from 1.0-1.4, at least that's what has worked best for me. Guns are cheap nowadays, so just get the right tools for the job. Eastwood has a package deal I think.

It's so good to see you at this point Drew!
"The way you think is the way you live"

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Re: Bodywork and Paint Help Needed

Post#4 » Tue Jul 03, 2018 1:06 am

Good to see you are still hanging in there. Just keep going one step at the time.

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Re: Bodywork and Paint Help Needed

Post#5 » Tue Jul 03, 2018 6:20 pm

Thanks for the advice, Vadim. I have experience using Bondo and sanding with a block prior to paint, but have never painted essentially bare metal. This is a new ballgame for me. I last did a truck about a month ago in the SoCal heat, but with temps approaching 107F this coming week, that stuff is going to set in seconds, not minutes. We'll see how good I am. Mixing properly is priority, and I think I'll do that in the shade if not in A/C.

I'm happy to apply that stuff thick and evenly, wait for it to dry and then sand probably an hour later. Gunna get some exercise in... looking forward to it!

The only stuff I have to worry about getting straight is the seams where Thor merged the '79 body shell with my '80. His work is factory perfect to the mm, but the big seams for the rear panels over the tires were welded from the outside as getting in there is near impossible. That's my biggest concern, as I have to grind down those welds and have to figure out what product to use to fill those gaps and smooth. The roof and all my pillars are perfect. I have some areas around the window holes that will need some love, as well as the D-pillar and front fenders. Hood is good as-is.

Much appreciated for all the work moving towards paint, but I'm not giving this old gal a glossy paint job. I'll likely be using Raptor liner that's color matched to DB-728, flakes and all. That gun needs to be 18-22" away from the surface for the rough texture I'm going for. Floors, the underside of the body and the inner fenders will be hit with 3M polyurea first and I don't care about overspray if I'm going to have to clean it up with the Raptor stuff later.
Project Puchy

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Re: Bodywork and Paint Help Needed

Post#6 » Tue Jul 03, 2018 6:21 pm

Johnny... this has been the project of a lifetime. Part of me wishes I'd just purchased a nicer truck. The rest of me is stoked that I'm giving this one a second life. Here's to shooting blue flames out of my custom exhaust when I shift gears.
Project Puchy

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kafkaonwheels
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Re: Bodywork and Paint Help Needed

Post#7 » Wed Jul 04, 2018 2:59 am

First, I am no bodywork technician or experienced painter. But I also did my G bodywork myself, currently under epoxy primer, needing still some pinhole etc. fixes and then it is ready for finer coats. It is a tough road to go, not sure if I want to do it ever again. I did read and watched lot of material before and during the job. There are various different approaches to do all this, I just chose what was available here and what I thought would give long lasting result.

Hopefully you already know this, if possible stay in one manufacture products (sealer, primer, paint etc.) and read datasheets before use (they all available from online for major companies). MB itself approves Glasurit, PPG Refinish, R-M, Spies Hecker and Standox.

With etch primer, you really want to find out the exact used product: first, some of them may cause problems to polyester filler when filler is applied directly over, compatible primer may be needed between; second, in datasheet there is recommended procedure for re-coating, some etch primers have no maximum time, some need just sanding, some need sanding and using one coat of same product etc. I think that to get it completely off you need to re-blast all the surfaces. I didn’t used etch myself, went for 2k epoxy.

For a shell I went for epoxy filler used in marine works: mixing ratio, work time (up to 60 min) and spreading is much better than polyester but price is many times higher, also little tougher to sand and longer cure time (+24h). Professional will probably roll their eyes if read or hear this.

I recommend keeping the doors to shell, getting them as flush and straight as possible and then doing least a rough filler work and sanding. Seen some trucks where doors don’t match the body, once the filler is on you cannot force adjust them.



Wish I could say it is easy work but it is not true, sanding filler is so dull that in most car shows cut it just to 30 second clip. But overall, rougher the journey, more you will grow and appreciate all other things. After first year in my project, I stopped counting hours, money and setting deadlines, rather enjoy process by trying to make all as good as I can detail by detail.

Good luck!
1985 300 GD Turbo (Project)

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VolvoC303
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Re: Bodywork and Paint Help Needed

Post#8 » Wed Jul 04, 2018 10:53 am

If at all possible, hire a body guy who wants some side work to help. Body work on this scale isn't something you can just figure out from watching videos or doing some light repair in the past. Don't let ego destroy all this effort. I have put a ton of trucks through this process in my rare 4x4 resto/importing career and even body shops sometimes (often) screw it up. There are endless tricks of the trade to bondo work and prepping, etc.. (And its ALL about prep) You run a huge risk of having endless issues down the road regardless of how it might look at first.

I know you are set on this dark color and bedliner paint scheme but I'd seriously consider how hot it's going to make your interior in the socal sun and how impossible it's going to be to spot rust and deal with that liner stuff down the road. You also can run into fitment issues with windows, trim, etc.. I've never seen it go well in the long run and forgot about re-selling it some years later. It will take massive man hours to strip that stuff off when that time comes, and it will someday.

I'll shut up now and go pee in the wind instead. :D
Off-road with the sound of a Mercedes diesel motor, the security of full lockers and a super-duty chassis.... that's why.

'79 300GD -617A

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Re: Bodywork and Paint Help Needed

Post#9 » Fri Jul 13, 2018 7:51 pm

kafkaonwheels wrote:First, I am no bodywork technician or experienced painter. But I also did my G bodywork myself, currently under epoxy primer, needing still some pinhole etc. fixes and then it is ready for finer coats. It is a tough road to go, not sure if I want to do it ever again. I did read and watched lot of material before and during the job. There are various different approaches to do all this, I just chose what was available here and what I thought would give long lasting result.


It's not my forte either, but I don't have a choice at this point. Luckily I'm down to bare metal all around (well, epoxy primer now) and there's really only a few problem areas I need to worry about.

kafkaonwheels wrote:Hopefully you already know this, if possible stay in one manufacture products (sealer, primer, paint etc.) and read datasheets before use (they all available from online for major companies). MB itself approves Glasurit, PPG Refinish, R-M, Spies Hecker and Standoff.


This is all very good to know. Thank you!

kafkaonwheels wrote:With etch primer, you really want to find out the exact used product: first, some of them may cause problems to polyester filler when filler is applied directly over, compatible primer may be needed between; second, in datasheet there is recommended procedure for re-coating, some etch primers have no maximum time, some need just sanding, some need sanding and using one coat of same product etc. I think that to get it completely off you need to re-blast all the surfaces. I didn’t used etch myself, went for 2k epoxy.


I'm a little past this at this point, but I'll find out what etching primer the shop used after media blasting. This is really good to know, and luckily it's been very hot and very dry lately in SoCal.

kafkaonwheels wrote:I recommend keeping the doors to shell, getting them as flush and straight as possible and then doing least a rough filler work and sanding. Seen some trucks where doors don’t match the body, once the filler is on you cannot force adjust them.


Luckily for me all the doors are currently on the truck. I was thinking about removing them for painting -- er Rhino lining -- but I may just swing them open.

kafkaonwheels wrote:Wish I could say it is easy work but it is not true, sanding filler is so dull that in most car shows cut it just to 30 second clip. But overall, rougher the journey, more you will grow and appreciate all other things. After first year in my project, I stopped counting hours, money and setting deadlines, rather enjoy process by trying to make all as good as I can detail by detail.
[/quote][/quote]

I have no choice but to enjoy the process. Some of the work at the base of the rock sliders is going to be particularly challenging, but past that, I'm not too worried. Gunna get some hammer time in before applying any sort of filler.

Thanks for the well wishes!
Project Puchy

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Re: Bodywork and Paint Help Needed

Post#10 » Fri Jul 13, 2018 8:25 pm

VolvoC303 wrote:If at all possible, hire a body guy who wants some side work to help. Body work on this scale isn't something you can just figure out from watching videos or doing some light repair in the past. Don't let ego destroy all this effort. I have put a ton of trucks through this process in my rare 4x4 resto/importing career and even body shops sometimes (often) screw it up. There are endless tricks of the trade to bondo work and prepping, etc.. (And its ALL about prep) You run a huge risk of having endless issues down the road regardless of how it might look at first.


Good to see you on here again, Vince! I will absolutely be looking into guys who are experienced with this and are interested in helping me out, but the truth is, I have enough money to install the engine and transmission, redo the wire harness and get a new windshield at this point. Mocking up the body work, the radiator, the shroud and placing the engine and transmission while making sure there's clearance for the shift linkage and the transfer case have been... time consuming and expensive. My plight for having a 1980 with the donut engine mounts.

VolvoC303 wrote:I know you are set on this dark color and bedliner paint scheme but I'd seriously consider how hot it's going to make your interior in the socal sun and how impossible it's going to be to spot rust and deal with that liner stuff down the road. You also can run into fitment issues with windows, trim, etc.. I've never seen it go well in the long run and forgot about re-selling it some years later. It will take massive man hours to strip that stuff off when that time comes, and it will someday.


A desert sand beige color on the outside, black on the underside of the body and black on the floor and up the firewall. My whole interior is redone in black, headliner included. I know it's going to be hot here, but that's why I have cooled seats and am tinting my windows as dark as I legally can with Llumar Air Blue tint, a ceramic tint that reduces interior temperatures by as much as 30 degrees F.

Regarding fitment issues, you've inspired me to spray some rust inhibitor around where the windows meet the body and I won't be hitting that with the bedliner... simply going to stick with something like POR-15 there. Trim-wise, everything mounting to the outside is rubber, save the door latches and handles, and I plan on using my old handles to push into the material as its drying. The truck's value will hold just fine if I ever decide to sell... but that's never been the plan.

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