Priming a shell

[PeterK]

I’ve booked my Targa for stripping with Envirostrip and had intended that they epoxy prime it after stripping. However, they no longer offer epoxy - only etch or weld-through primers.
My understanding is that I can’t spray epoxy over etch but what about over weld though?. My suspicion is that weld through would need to be removed before epoxy is applied but is that correct?

If so, how should I remove it - wipe with celly thinners or sand off?

Would I be better getting a bare shell returned and epoxy it quickly ?

Thx
Peter

[inaglasshouse]

Bare shell, surely?
Next step, presumably, is a load of inspection, fabrication and welding to fix all the rust. You can’t tell anything in detail about the state of the metal, after it has paint on it. Ask me how I know!
So to properly evaluate it needs to be bare metal.
It’s a misconception to think that a shell will immediately rust in a dry-ish workshop environment. You have months or years to play with, if you need them.

[inaglasshouse]

Also Envirostrip - I’d advise a search on here before going down that road.

[KS]

Also Envirostrip - I’d advise a search on here before going down that road.

You're not confusing Envirostrip with a certain other Midlands-based company that offers a similar service, are you?

[RichardBTek]

Hi Peter

Richards right you'll have quite along time before the shell starts to deteriorate if you keep it dry and well aired. You'll need to assess work required before you cover it with paint and you can clean and prime repaired areas as you go. There's no point in priming things you are going to throw away either. I etch primed the areas that required little or no work (dash, engine bay etc) to reduce deterioration and work at the end.

Richard

[inaglasshouse]

Also Envirostrip - I’d advise a search on here before going down that road.

You're not confusing Envirostrip with a certain other Midlands-based company that offers a similar service, are you?

Hi Keith,
Not confused. About this, anyway!
Cheers, Richard.

[PeterK]

Thanks guys - sounds like a nice saving by not getting it primed. So I guess bare metal shell returned by Envirostrip in a covered trailer, quick scuff with pads, wipe down with panel wipe, then a rust passivating wipe, then another panel wipe, then spray is the way to go. Guess that means that Xmas will be spent 'paint prep-ing' the garage !

I know there are horror stories about all of the methods of stripping, but Envirostrip are the least scary for me in the risks of panel warp, rust re-appearing, paint not sticking or leaching of chemicals. I intend to check critical dimensions with a big stick (aluminium beam with pointy things on each end) when it's back

I don't fancy trying to hand strip all of the car and am hoping (naivety at its best ) that there won't be many areas to treat. I've spent 18 months finding and removing rust and bodged patches. All that's left are the major panels where I can't see from the inside, where of course there is always the chance that there is rust or damage covered by filler.

Peter

[jtparr]

Peter

Envirostrip were great for the E

I did a quick scuff pad clean and wipe down before I blasted epoxy over what I could at the time ....maybe a week after the shell was returned to me

The process they use seems to leave a gentle residue like the POR-15 Metal ready product...like a zinc passionate effect

A lot of the car was still pretty good and clean even after the 18months or so between Envirostrip and Barry completing his work

Jonathan

[911hillclimber]

I have just hand removed all exterior paint (cellulose top coat, primer filler on bare metal applied in 1989) using paint stripper and elbow grease.

The bare steel panels showed surface rust, a pale rust colour ghosting over the areas, in 4 days at most, some areas in 2 days.
Unless your work space is humidity controlled I think you will have acute surface rust issues on a bare shell within a week now the weather is changing.

If the process you have considered, done in the Midlands or not, was bad, that process would have been dumped by the classic car industry years ago.
I used the 'Midlands' base a few years ago on some Lambretta panels, sure worked, from a solid looking side panel to more pin holes than the stars in the Milky Way.

A de-humidifier could be your best friend?

[Gary71]

A de-humidifier could be your best friend?

Mine is running flat out

[inaglasshouse]

The bare steel panels showed surface rust, a pale rust colour ghosting over the areas, in 4 days at most, some areas in 2 days.
Unless your work space is humidity controlled I think you will have acute surface rust issues on a bare shell within a week now the weather is changing.

Yep, need to keep the environment dry. But if you do, you have ages. The oxidation reaction simply doesn't happen without water.

My shell spent the best part of 6 months with Barry, without any paint on it. Very little surface rust, and getting rid of it before paint was a tiny part of the job.

And my '65 car, unrestored, has some areas where the underseal long since departed and it's back to bare metal. That survived as shiny steel in Arizona and Southern California probably for many years, and is still shiny in my dehumidified garage. I've found the Mitsubishi dehumidifiers great.

[inaglasshouse]

BTW I wasn't trying to imply that Envirostrip is a bad company.
But depending on context I'm not a big fan of the process, for reasons Jonathan very helpfully illustrated in his thread:
viewtopic.php?f=43&t=55758&start=195#p562116

For me, for a 911 a shell in reasonably decent condition, there are too many spot welded seams with a very close fit, which have been happily sitting for years and not rusting (either because they had paint on the components pre-assembly which was not destroyed by spot welding, or more likely because they were seam sealed / painted shortly after assembly). Acid treating those close-fitting seams, then leaving a residue behind with no way of flushing it out and re-treating the area, does not seem like a step forward to me.

With that said, you know the risks, and blasters have destroyed perfectly good panels too. It also depends on condition - for the "E", or indeed for my 70 911, so much metalwork would ensue that those inaccessible areas would probably all come apart and get proper attention anyway.
Not sure there is a perfect answer...