Hi, has anyone stripped the paint down to the whatever plastic the fairings are made of? Lots of tight curves and soft material, seems like potential to make a mess.
Do I need to go that deep?

My auto paint expert advised against taking it all the way down when I did this so I just cleaned and sanded to abrade the surface.  How you prep might depend on what you are spraying though.  I used a Sikkens automotive enamel.  I did not have to prime first either but I would probably do this since I was spraying white over maroon and the nicks and scratches show a lot more than if there was grey primer underneath.

I have done a lot of paint on bricks in the past 6 years(three repaints, two major touch ups + a lot of drop repair).

My prep on painted parts that aren't having the color changed is to wet sand with 600 wet-or-dry to remove the shine.  For color change, I wet sand with 320.   Prep for fiberglass repair involves 80 grit on a disc sander.

I use a light gray high build primer under my paint jobs.  Wet sand with 600. 

Defects are filled with 3M acrylic glaze.  Sand with 220 or 320 then prime with the light gray High Build.  Sand that with, you guessed it, 600.

I use acrylic auto enamel with a clear coat.  No sanding between coats of base or mid coat.  After a light coat of clear I put down five medium wet coats of clear.  Make sure to let the paint flash for at least five minutes between coats.  Make sure that edges get a good coat of clear.  They are hard to get paint on, and easy to sand through.

After 24 hours, wet sand the orange peel with 2000 followed by 2500 and buff out with 3M Perfect-It steps 2 and 3 with a power buffer and 3" foam pads.

Be careful with the parts for at least two weeks.  Even the two part acrylic clears take that long to reach full hardness.  The single part clears often take longer.  Anything in contact with the part for an extended time before the clear fully cures will leave a mark,  The paint is especially sensitive to gasoline for at least two months.

I always use the two part rattle can clear on fuel tanks now to get the best fuel resistance.  A bit more expensive, but holds up a bit better.

Thanks, I guess I was a bit hesitant to paint over the clear, I will go the clean and rough up, prime route. Are you guys using cans of spray paint, or a HVLP gun to spray the paint?

Depending on the size of the part I use either a cheap Badger 250 airbrush or a Harbor Freight HVLP(the cheap one) for base coat.  There are You Tube videos on how to prep that HF gun for good performance.

I do primer and clear from rattle cans.  I hate cleaning guns.  The most important parts of my paint jobs is the prep and the wet sanding and buff on the clear.  I don't really agonize over laying down the base coat.

My paint jobs are not show or OEM quality, but still look pretty good, even up close.  My bikes are for riding.  The one in my avatar was done on a collection of mismatched parts to do sort of a SE paint scheme.

I use an HVLP conversion gun (run off of an air compressor).  I used to have an HVLP turbine rig but never saw it as being that much better for spraying mostly small parts.

Thanks, I am working with a mis-match of parts as well. The air brush may be useful for the vents in the lower fairings. I am not looking for a flawless finish for the bike,but I don't want to look like an idiot either, My son and I redid a 69 MGB a few years ago and did the paint our selves,came out pretty good, we used a two part enamel , no clear coat., tough to buff out , it is easy to take the paint to the primer on corners. I will be going with what I think is Madison Silver, that is what the bike is mostly now,it was an RT but I am putting RS fairings on it.

I know how hard those two part enamels can be.  They were designed to not need buffing, but you needed a robot to put on the right amount of paint without dry spray or runs.  I have used Awlgrip and Imron and hate them.  Terrible to work with, and almost as toxic as chemical warfare weaponry.

1K acrylic enamel works pretty well for me.  Since the base doesn't need to shine, I put on lots of fairly light coats until I have the color density I need.

Lately, I have been using a 2k acrylic clear in a rattle can.  It's a couple bucks more per can, and once I activate it there is no storing it for more than 5 days, and only if I put it in the freezer.  It seems to hold up better to fuel than the 1k stuff.  I like to let it cure for at least 4 weeks before getting gasoline near it.

To avoid sanding through, I try to get extra coats on corners, trying to get them wet enough that there is little chance of orange peel.  I try to keep the edge of the spray pattern where the dry spray tends to form on flat areas where it's easier to sand.  I lay all my parts as flat as possible when I paint them so critical surfaces are horizontal to minimize runs.  Let the coats flash for at least 5 minutes(10 is better) to help prevent runs.  Patience is golden.

Thanks guys, I took the bike out yesterday for a nice ride . I love the RS fairing, Its going to be a lot of work to get them to match the bike. I am tempted to find a lower mile none cobbled together Rs and ride that. This bike is a high mile bike I bought ten years ago and have gone through it with parts from all over , motor ,transmission, rear drive ,all from different bikes.

I have chosen a color that is similar to the one that is on the bike now. I am gong to paint the whole bike. The color I want is Nantucket blue from a 69 Chevy Camero.

When we painted the MG we used PPG paints, It is very confusing trying to find paint here, I guess I will see if the PPG dealer is still around, still have to drive 45 miles though.
point seven five, what brand of paint are you using?

The place I get my paint is a DuPont dealer as well as a couple other brands.  The cans of paint and the sale receipt name Chromax and Chromabase.  I am not sure if it's actually a DuPont product anymore as I seem to have heard that DuPont has changed lines or something.  It may be the paint dealer I go to has changed suppliers.

In any event, I'm using an acrylic 1K system of base and clear coat.  Since the clear is universal as long as it is acrylic, I use Jammin' Clear or a 2k that I can't recall the name.  They both come in rattle cans so I don't have to hassle with cleaning the gun when I am done.

If I were you, I would just go to a place that supplies the local collision shops and get their 1k acrylic base and clear.  They are all pretty much the same.  The big thing is if they can match the BMW colors.  My guys are pretty good and have been able to find formulas or close matches.  For example, they have found that Ford's Fire Red is an almost perfect match for Mystic Red.  Most of these paint places can match the color if they can't find the code.  The important thing is to not come in at the end of the day, and be patient while they search for your match.

Update. I have prepped all the parts and sprayed them with sealer , when I sprayed the sealer I realized painting the front and back of the muti shaped parts front and back is going to be tricky. Do you guys hang the parts or set them on a table or racks?

I usually hang them as it makes it easier to get in the tight and curly bits. If you haven't already bought the topcoat and you're not using HVLP, go for acrylic 2K rattle cans rather than 1K. It's tougher but apparently has the disadvantage that most pro paint shops say it's only good for eight hours after you've pulled the activator. This is 'passed on' information from research. I'm about to respray my RT from the ground up and I used to use HVLP blowing cellulose topped with enough clearcoat to fall into, but the law has changed on VOC paints.  Also, I no longer have a workshop where I could close one end off for painting so HVLP is out for me. Hence, I've spent a lot of time researching and reading up on the more modern stuff. 2K acrylic definately seems to be the way to go.

I still hate rattlecans with a passion and I still really miss my old DeVilbiss JGA. PointSevenFive is right on the mark with one thing though: cleaning out HVLP guns is a real PITA. You could always tell what colour the last bike I sprayed was by just looking at the paint runs on the wall... and the floor... and wherever else I'd sprayed the cleaner. The upside was it was great for sealing the walls!!!

The only acronym/abbreviation I didn't have to look up was PITA!

Shows how long it is since my last venture into automotive finishes. There will be some in my future, so a refresher might just be needed

Bill

Dai, I use this 2k clear:

https://www.ebay.com/itm/SprayMax-3680061-2K-Glamour-High-Gloss-Clear-Coat-11-8-oz-1-Case-6-Cans/362071612205

6 cans is just about enough to do 3 medium wet coats on the bodywork on a K bike with a 7th if you have a belly pan.

Make sure you shake well before and after popping the hardener.  The spray pattern is a nice fan with decent atomization.  A quick upside down shot clears the nozzle between coats.

I have had good luck with putting the leftover catalyzed clear in the freezer where it stays usable for up to a week.  Just put the can in a bucket of hot water for 10-15 minutes to warm it up before you use it.

I have a table top paint booth that handles 1 or 2 parts at a time.  It's really nice to not have to worry about clear flashing off in the gun while I change parts on the turntable.

Guys when you talk about 2k paints, is this the isocyanite (probs not spelled right) stuff that's supposedly pretty toxic?
I ruled it out for my own respray because I wasn't sure how far to go with the breathing/extraction gear/back garden acceptability.
In the real world, what measures do you take/recommend for home jobs?
Cheers
chris

Hi Chris,A good quality respirator is a MUST.Whether spraying in a 5 Acre field or indoors.The gas propellant used in cans, adds to the breathing hazard and also 
lowers the point of flammability.1K-2K-2KX just more of the toxic stuff for harder/shinier parts.Have fun breath in AND out

2-pack is as toxic as fck. A good mate used to spray it using a full-body positive-pressure suit for protection. If you want to breathe in 2K acrylic fumes directly yeah - it could be very nasty but a reasonable 3M respirator (e.g. the 6121M fitted with a VOC cartridge) would be okay providing you don't lock yourself in a cupboard to do it. Bear in mind that 2k is available off-the-shelf and 2-pack isn't. Read what it says on the tin. The nearest 2K supplier to you is just up the road from Motorworks (!)

http://autopainthuddersfield.co.uk/

They're 'away till May 12th' (lockdown?) but there's a few videos on site and a phonecall wouldn't go amiss when they're open again. I'm going to use these guys for paint because they have a very wide range and I will be talking to them about PPE.

Ah - I never answered your question. Yes, it does use isocyanate for the hardener but it's a tiny quantity.

Damn - can't find the videos any more. It's been about three days since I checked their ebay site and it looks like stuff is scrolling off because they're away.

Most of the paint being sold for auto repair is acrylic and the 2k stuff is toxic, but not as bad as the heavy duty polyurethane industrial stuff like Imron or Awlgrip.  The commonly available acrylic is more of an irritant and serious problems seem to occur only after prolonged exposure.  Still, you want to take precautions when you use it.

I have built a small tabletop paint booth with fans and filters to control overspray.  I wear a NIOSH organic vapor mask and goggles to protect my eyes from any overspray that escapes the booth.  I paint in my garage and leave the door open while painting.  Because the door is open for ventilation, I try to shoot early in the day before the flying bugs wake up and start cruising.

A note on masks.  Organic vapor cartridges will absorb stuff from the atmosphere while they're just sitting around between jobs.  Eventually the carbon that does the vapor removal gets saturated and stops working.  THen you need to replace them.  Keep your mask in a ZipLoc plastic bag between jobs.  And wipe down the inside with a little rubbing alcohol before you put it away so it smells better the next time you wear it.

You can download MSD sheets from the websites of the companies that make your paint.  Definitely a good idea to check out the recommended safety procedures. 

The websites also have technical information on mixing and application.  Things like reduction ratios and flash times are important as well as setups for guns.  Never assume the application requirements.

If you can't get the information on the interweb, ask the paint dealer.  They will have the information.

Finally got it done. RT to RS. collected all the fairings from all over, got them painted and installed. I took 1 inch out of the rise of the RT bars. 
Works well for me 
Thanks for the help.

 

Good job!