Money Pit: The Sequel - Full Repaint Project

[bmwman91]

It has been a little while since the last update, but actual progress is happening. The paint shop needed to get a few other jobs cleared out of the queue, so the car sat for a few weeks while that happened.

Despite the delays, the car is at the shop and fully underway! When I dropped the car off at the start of the month, the general thought was that it would be done sometime around the end of the month, or maybe early August. If it is done later than that, it is fine too as I am in no rush! Due to some house remodeling plans that I have had, I think that the best course of action after the repaint will be to put it into a self-storage unit for ~2 months while I sort out the house stuff. That will give the paint ample time to finish hardening in a place which is out of reach of cat claws. Bringing it home and putting it under a cover is a no-go since the painter said that the paint would be soft enough to pick up some texture from a cover until it has more time to finish curing (they bake the paint, but that only does so much).

The other thing is that I am due to SMOG testing by early September, and the car is 100% not going to be reassembled by then. I may be able to find a shop to do it on the disassembled car since all of the engine and emission equipment are still fully intact and in proper working order. Worst case, I pay the PNO fee and then properly re-register it a couple of months later or something.

A couple of additional to-do items have also come up. I want to replace the front windshield since it had some chips in it, and I managed to chip the bottom perimeter when moving the wooden glass rack around...a little rock got between the glass and the floor and that was that. I will call around to some glass shops this week to see if I can get an E30 front windshield. The other items that I will need to order are new / reproduction VIN and information stickers for the body and door jambs. Those were removed for the repaint. It sounds like there are a few places that make them, although they are not cheap.

[DEV0 E30]

Great work and detail in your posts. Looking forward to more!

[bmwman91]

Donor parts are always easier if available, but I've seen guys turn a piece of sheet metal into a windshield channel patch panel with a brake, a shrinker and some weird hammers and some dollies. I've also seen pinholes in a panel like your roof fixed by a spot weld which is then ground down.

I see. No question, if there are any actual pinholes or spots that look questionable, they are getting TIG'ed and ground. Maybe even some small cuts and patching depending on what the body shop thinks once they are in there and have all of the paint off. I am going to ask them to go through the entire sunroof opening to sand off the paint and scrape out as much old body sealer as possible as part of prep, and then reapply body sealer to the entire exterior perimeter of the joint between the roof shell and sunroof cassette before painting. It isn't a roof replacement, but it should keep water from wicking into there again like it has been with the nasty old and cracked sealer.

[varg]

As far as cutting and patching as you suggest, do you mean cutting out the areas around the front corners and having replacement sections welded in, both on the cassette and roof skin? For that, I assume that I need to locate a clean donor car to chop them out of?

Donor parts are always easier if available, but I've seen guys turn a piece of sheet metal into a windshield channel patch panel with a brake, a shrinker and some weird hammers and some dollies. I've also seen pinholes in a panel like your roof fixed by a spot weld which is then ground down.

[bmwman91]

There's no short way out of the rust problem but to remove it all and replace with good metal if the remaining metal is too thin. No seam sealer or chemical will stop the process short of caking the metal in something like cosmoline. Any rust converting agent will also cause paint adhesion issues. In a dry climate it will progress slowly but if you're already torn down to almost a bare shell and painting you may as well repair the panels correctly since much of the labor (removing glass, headliner, sunroof parts) is done already. Cutting and fabricating the patch panels alone isn't going to be days worth of labor for a competent sheet metal man and will cost barely anything in parts given the scope of the work already being done. If you do sell your E30, your quality and well documented restoration showing you didn't skip steps will help your resale value too, look at it that way as well.

Yeah, part of my willingness to gamble with a temporary fix here is the fact that I can keep this away from liquid water (outside of washing, and it will at least have fresh sealer over the outside of the joint which should keep water out anyway), and humidity here generally maxes out at 70%. So really, I think that atmospheric water vapor is going to be what ensures that the existing rust continues to creep along slowly.

If the converter will make for tough painting, then I am going to be better off without it.

As far as cutting and patching as you suggest, do you mean cutting out the areas around the front corners and having replacement sections welded in, both on the cassette and roof skin? For that, I assume that I need to locate a clean donor car to chop them out of?

[bmwman91]

Sunroof cartridge is a bit of a bummer but its workable. I would try get up around the edges with rust converter in a spray bottle. Agitate it with a brush and spray it out with some wax and grease remover. Hair dryer/Heat gun it dry and unload a spray can in the edges the best you canto give it a good barrier. The cartridge can be removed but you will upset the shaping around your sunroof opening due to the process required to drill out spotwelds and jimmy the roofskin off the sealant. Getting the roofskin perfect again is a shit time. I had to buy a new frame as it basically acts as a Jig to set everything perfect again. Honestly I think it would of been easier for me to just go a slick top. Then there is the issue of the sunroof itself. They rust inside out as they aren't painted from factory internally. They should of dipped them! Something else I had to buy new due to buying 3 sunroofs only for them to be rusted out.

you're doing a great job so far tho! I quite enjoyed getting all the little parts cleaned up and restored. The SEM paint is glorious, brilliant on your door frame trims too.

Wow, yeah I think that a roof replacement is definitely out of scope for this project. It sounds like something you really need an experienced professional for. I have seen at least one project on here where it was done, and I recall it being no joke!

On top of the bad decision to not dip stuff up there, the main failure of design that I see is that the corners at the front where the outer roof shell was broken over and down are shallower than the straight parts. I assume that this was due to limits on how the metal would flow in the forming process, but it left the joint well within the height of the fuzzy sunroof gasket. So, basically a wet sponge is sitting in contact with the corner joints and once the body sealant gets any cracks, water is going to wick in constantly. Stupid!

[varg]

Oh, and varg did you just spray the converter on the visible areas, or did you spray it into the joint? I am researching converter products and am wondering if they would cause any adhesion issues if they are applied and then left on, particularly in something like the roof-cassette joint.

I haven't removed the panel since I replaced the rusted out stock panel, and it hasn't been opened, only tilted up, since then since the rods that push the drip rail back were rusted up and damaged in removal. It is purely an act of applying ospho to visible rust with a dropper to slow it because my E30 can't be garaged and driven only on dry days until the wagon is on the road. No rust converter is anything other than temporary slowing of the rusting process, it only chemically reacts with a shallow layer of steel and that layer is still permeable to oxygen and water since rust is very porous.

How long would you say it was between when you bought the car (with things in about the same state as mine) and now with the millimeter size holes? Has the car been in the rain much?

Yeah, I am bummed to see the rust there, and I know that anything short of full cut-and-weld is not a solution, only a delay of the inevitable. If a local donor car appeared tomorrow with a rustless roof (sunroof or not), I still wouldn't do it because I am fairly confident that I would be looking at $10K in additional labor, and I am not even sure f this shop would be willing to basically more than double the amount of time and labor for this since they have a high volume of normal repair business to handle.

I am in awe of the restorations that some other people on here have done, but I just don't have the time or money for that sort of thing. There's a tough conversation in my head here. On the one hand, I am spending a not-insignificant amount of money on the parts and paint job, so obviously the idea of leaving the roof in this state begs the question of "why bother?" On the other hand, I think that careful cleaning and sealing combined with keeping the car out of the rain should buy me several years of additional enjoyment form this car. The humidity here basically never gets above 70%, and I can keep the car covered and/or garaged when it rains. In the end, when the car is finally in a state where I will either need to do the roof swap or scrap it, I am still not out as much money as someone who buys a new M-series after 5 years of depreciation.

As far as mitigation, I am also leaning toward wire brushing, converting, neutralizing, and injecting with seam sealer. The body shop can sand down the whole perimeter in the sunroof bay and apply sealer in there before painting. Since this bit of rust was not part of the original estimate, I need to go talk to them about what they can or will do there, versus prep that I may be better off doing myself. I may also be able to make some small stainless scrapers to get into the gap between the roof and tray to get as much crap out of there as possible before filling.

I've had my car for 9 years and it has been consistently exposed to Florida rains during most of that time, and mostly garaged when not in use for the past 5 years or so. It has not been garaged for the past 8ish months and the rust has progressed visibly in that time. I have also wire-wheeled the bubbles, treated with ospho and sealed with superglue 3x over the last 5 years, the roof pinholes first appeared around the time I got a garage, rusting from inside out, no doubt in between the roof panel and the cassette.

There's no short way out of the rust problem but to remove it all and replace with good metal if the remaining metal is too thin. No seam sealer or chemical will stop the process short of caking the metal in something like cosmoline. Any rust converting agent will also cause paint adhesion issues. In a dry climate it will progress slowly but if you're already torn down to almost a bare shell and painting you may as well repair the panels correctly since much of the labor (removing glass, headliner, sunroof parts) is done already. Cutting and fabricating the patch panels alone isn't going to be days worth of labor for a competent sheet metal man and will cost barely anything in parts given the scope of the work already being done. If you do sell your E30, your quality and well documented restoration showing you didn't skip steps will help your resale value too, look at it that way as well.

[bangn]

Sunroof cartridge is a bit of a bummer but its workable. I would try get up around the edges with rust converter in a spray bottle. Agitate it with a brush and spray it out with some wax and grease remover. Hair dryer/Heat gun it dry and unload a spray can in the edges the best you canto give it a good barrier. The cartridge can be removed but you will upset the shaping around your sunroof opening due to the process required to drill out spotwelds and jimmy the roofskin off the sealant. Getting the roofskin perfect again is a shit time. I had to buy a new frame as it basically acts as a Jig to set everything perfect again. Honestly I think it would of been easier for me to just go a slick top. Then there is the issue of the sunroof itself. They rust inside out as they aren't painted from factory internally. They should of dipped them! Something else I had to buy new due to buying 3 sunroofs only for them to be rusted out.

you're doing a great job so far tho! I quite enjoyed getting all the little parts cleaned up and restored. The SEM paint is glorious, brilliant on your door frame trims too.

[bmwman91]

Here is a week's worth of photo dumpage...not in chronological order.

I got a variety of smaller prep tasks out of the way this week. One random thing that I did was to clean up the front AC evaporator shroud thing. It was looking pretty badly oxidized and sad. Maybe 15 years ago these would have been cheap and easy to come by, but that is not the case anymore. I am not sure what material it is exactly, but it is some sort of thermoplastic. It feels like polyethylene or polypropylene just based on its very slick feel and the way that a knife cuts into it. As will become a theme later on in this post, I got some use out of my little MAP/Pro hand torch. You can see the ugly oxidized area, and the small part I ran a quick test on.




This is one of those things that takes a patient, gentle touch. Don't try to rush it by stopping at any point with the flame, just keep moving and make another pass. After doing the top faces, the part was fairly warped. So, I flipped it over and did the bottom side (which did not need it as badly, but it did benefit from it anyway). After hitting both sides it was straighter than it was before I started (it was pretty badly potato-chipped all on its own). It is a little hard to tell in the picture, but the surface was not all that even in appearance and had some streaks. As far as I can tell, it was just plasticizer leeching onto the surface after the reheating.




A quick wipe with some acetone and a wash with Simple Green had it all looking really good by the end.




You have to be careful when working around little thin areas like this or they will melt / burn away pretty easily. As tempting as it was to hover around here to try to get the oxidation out of the bottom corners of the recess, it was going to lead to bad times. These are covered by rubber bits anyway.





Another, bigger, task was to refinish most of the black painted metal pieces that are part of the sunroof mechanism. At first I ran an experiment by sanding the front-most top covers lightly and then spraying them with SEM Ultra Trim Black. This stuff is awesome BTW. Not the cheapest, but it goes on without any primer as long as things are clean, it dries fast, and is pretty damn durable for a rattle can product. Oh, and try not to breathe it, it smells like cancer even more than normal spray paint.




The top of the long rear rails was in OK shape, but had some minor rust pitting at the front.




Unlike all of the other parts, I am not going to get these powdercoated. They are riveted on to the lower portion of the rails, and while masking would keep the paint off of there, there just isn't a good way to a) get all of the grease out of the gap between the pieces, and b) get the paint up inside the top plate properly. I debated milling off the flared part of the rivets to separate the pieces and get a proper powdercoat job going, but the risk of making a big mess of these NLA parts is too high. There are some on eBay that I considered buying to experiment with, but I would rather not ruin perfectly good ones that someone else could use if my idea didn't work out.




Anyway, I hit them with the wire wheel and some brake cleaner, masked them up, and blasted them with paint. They came out looking pretty good overall. I did not remove all of the original paint so there are some slight uneven spots near the front where rust had broken it, but nobody but me will ever see this. The underside where the sliding parts all go is still sort of bare metal which isn't ideal, but again I am not going to try to separate the parts.






I tried out the same technique with the front top plates, but I did not like the pock-marks from the old paint, and as durable as the SEM stuff is I do not like the idea of sliding parts rubbing on it.




So, it was time for more fun with the hand torch. It made quick work of the paint, old and new. I think that the original paint was a powder coat product.




I had to make a couple of passes with the torch and wire wheel to get these properly cleaned (picture is after the first pass).




After another pass.




Next I gave the burniness to the rest of the metal parts from up there. All of these will be going off to the powder coater this week for a refresh. DIY'ing the prep work should save me some money. The headliner frame warped a little when I made the first cooking pass due to me pausing for a few too many seconds in one spot. It was nothing major, but I was not super happy about it, so I got out the second torch and deliberately overheated the same spot on both sides simultaneously and that took out 90% of it.




Everything got a quick pass with a metal finishing abrasive pad by hand, and a wash. Honestly, cooking the headliner frame was probably 5 times faster than trying to remove all of the old spray adhesive with solvent lol. FIRE!




There were some little rubber bits that had been on the frame, which I peeled off. Sadly, the solution to the old rubber cement on these was not fire. It was lots of scrubbing with acetone and a brass bristle brush. I briefly tried the wire wheel on my grinder, but that was going to eat the part so I had to do it the old fashioned way. All in all it took maybe 30 or 40 minutes.






The front portions of the 4 bumper shocks got the wire wheel to knock off some rust, some brake cleaner, and the SEM paint. the rear portions were not really rusty, and I wanted to keep the OEM part numbers and markings visible, so I masked that stuff off.




I spent a bit of time up in the sunroof opening with acetone and a rag removing the old spray adhesive from the headliner. Ultimately since it is all 100% accessible now, I may just have the paint shop go all the way in to the rim of the inner opening, so the little bit of remaining adhesive can be dealt with by them. I used a long wooden paint stir stick to scrape out the rest of the grey butyl rubber sealant strip material that was out of reach.

Also on the list this last week were the window regulators. They were both in good shape and mostly just in need of cleaning and some fresh lubricant, but on both sides the plastic roller things were either not rolling super nicely or actually a little lose from wear. I took measurements and can pretty easily turn out some new ones on the lathe, but that would require cutting off the riveted axles and making something new to replace them.




So, since new regulators are still available form BMW and not too badly overpriced, I just got some new ones. I will still try to properly refurb this pair and sell it in the future, but since I am not 100% sure about what I want to do there I am just getting new ones. The motors are NOT part of the regulators, and NLA. Even of they were not NLA, they were hideously expensive back in the day. These motors are perfectly good still and just in need of a little cleaning. This coming week I will actually pull the rotor portions out to inspect the brushes, but I expect them to be fine.






Externally, they just needed some new harness tape, a wipe with some acetone, and some brushing to get the old grease out of the spur gear. I'll add some new grease to the gearbox when I receive it (Loctite LB 8034 as recommended by Jordan).






One of the threaded holes in the gearbox was starting to strip, so I decided to put some of my extra Helicoils to use. The stock screws are some ST4.8 (approx. M5) self tapping things, so it was a prime target for my M6 inserts




Since these are shallow blind holes, I needed to turn the provided taper-tap into a blind-tap. A grinder makes this pretty easy. When you do this, always start the threads with a tapered tap as a blind tap will both not start them very nicely nor will it cut easily, especially when it's been ground down like this. Soft materials like plastics can easily get screwed up if you are not careful with one of these "special" taps.




The repair went fine, and I was able to sink the insert a couple of turns, so I don't expect to have issues with it. Never leave these things flush with the top of the hole or they will just start stripping out. Always sink them at least a full turn, better two or three if possible.






Cleaned up motors.




There is not too much else to do to prepare at this point. The sunroof parts should take a week or so to get back from the powder coater, some grease for window and sunroof related stuff is on order, and I am corresponding with CATuned now about the headliner material that I want. Per a Youtube video, I saw that you can get either the Euro cloth, or the German cloth for the non-suede headliners. Both look nice, but the German one has a tighter looking weave which I prefer. Once I pull the trigger on that, I think that I might actually be done buying things.

The main hold up is the set of replacement sheet metal parts for the rear tail where the rust patch needs to be chopped out. The items are in the mail, but the international shipper does not have very granular tracking information.

[bmwman91]

subbed! can't wait to see it all freshly painted

Thanks! Yeah I am really itching to have this project done, although it is very likely to be ~2 months until it is back in one piece again!

[s-thetikz]

subbed! can't wait to see it all freshly painted

[bmwman91]

Oh, and varg did you just spray the converter on the visible areas, or did you spray it into the joint? I am researching converter products and am wondering if they would cause any adhesion issues if they are applied and then left on, particularly in something like the roof-cassette joint.

[bmwman91]

Lovely progress. Coming along nicely.

Thanks, yeah I am relieved to be done with the disassembly part of it. A lot was learned along the way!

NIce progress. I feel blessed to have a slicktop. I am more and more convinced to do the prep work and remove it all myself. Just need to find a shop and start the hunt.

Slicktop for the win! I do love having the sunroof on nice days, but if I had been able to find a slicktop back when I was buying this car I would have done it. The extra head room would be nice too...when I have a helmet on, I have to open the sunroof and lean over lol.

Following this one, it's good to see the process in detail. It's really interesting to see all of the parts laid out like that, I haven't seen it before.

My sunroof area is significantly worse than yours, but I still think your sunroof cassette and associated panels will need to be removed to fix it properly since there is rust between the panel seams. I'm guessing it'll be cheaper to convert my car to a slicktop than to repair all of the rust around the sunroof cassette and the hidden rust that inevitably will be in it as well, but your car has less than half the rust up there that mine does. Mine looked about like yours when I got it - one pinhole near the sunroof showed up shortly after I bought it, now it has multiple 1-3mm holes around the cassette over the driver's seat which are currently wire-brushed, treated with ospho and sealed with superglue. For me, the floor rust is good welding practice and then do the battery box can follow, with chip guard on it would be hard to tell that the welding isn't perfect.

How long would you say it was between when you bought the car (with things in about the same state as mine) and now with the millimeter size holes? Has the car been in the rain much?

Yeah, I am bummed to see the rust there, and I know that anything short of full cut-and-weld is not a solution, only a delay of the inevitable. If a local donor car appeared tomorrow with a rustless roof (sunroof or not), I still wouldn't do it because I am fairly confident that I would be looking at $10K in additional labor, and I am not even sure f this shop would be willing to basically more than double the amount of time and labor for this since they have a high volume of normal repair business to handle.

I am in awe of the restorations that some other people on here have done, but I just don't have the time or money for that sort of thing. There's a tough conversation in my head here. On the one hand, I am spending a not-insignificant amount of money on the parts and paint job, so obviously the idea of leaving the roof in this state begs the question of "why bother?" On the other hand, I think that careful cleaning and sealing combined with keeping the car out of the rain should buy me several years of additional enjoyment form this car. The humidity here basically never gets above 70%, and I can keep the car covered and/or garaged when it rains. In the end, when the car is finally in a state where I will either need to do the roof swap or scrap it, I am still not out as much money as someone who buys a new M-series after 5 years of depreciation.

As far as mitigation, I am also leaning toward wire brushing, converting, neutralizing, and injecting with seam sealer. The body shop can sand down the whole perimeter in the sunroof bay and apply sealer in there before painting. Since this bit of rust was not part of the original estimate, I need to go talk to them about what they can or will do there, versus prep that I may be better off doing myself. I may also be able to make some small stainless scrapers to get into the gap between the roof and tray to get as much crap out of there as possible before filling.



Of course, discussion and opinions are welcome here. If I'm being an idiot feel free to let me know! And if anyone has had a similar situation and made a temporary repair of some sort that has lasted a decade, I am interested to hear about it.

[varg]

Following this one, it's good to see the process in detail. It's really interesting to see all of the parts laid out like that, I haven't seen it before.

My sunroof area is significantly worse than yours, but I still think your sunroof cassette and associated panels will need to be removed to fix it properly since there is rust between the panel seams. I'm guessing it'll be cheaper to convert my car to a slicktop than to repair all of the rust around the sunroof cassette and the hidden rust that inevitably will be in it as well, but your car has less than half the rust up there that mine does. Mine looked about like yours when I got it - one pinhole near the sunroof showed up shortly after I bought it, now it has multiple 1-3mm holes around the cassette over the driver's seat which are currently wire-brushed, treated with ospho and sealed with superglue. For me, the floor rust is good welding practice and then do the battery box can follow, with chip guard on it would be hard to tell that the welding isn't perfect.

[monty23psk]

NIce progress. I feel blessed to have a slicktop. I am more and more convinced to do the prep work and remove it all myself. Just need to find a shop and start the hunt.