The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Melena on June 16, 2010, 10:49:28 PM
-
I'm not sure this should be in the tech section, but it is kind of technical so here goes.
Since I crunched my front fender on the way to the 49er Rally, I had to get a new fender. Luckily I found a used fender in good condition except for the paint and the dirt on the underside. It looked like it was off of a bike that was used to bushwhack through the desert. The front part didn't have any paint left. So, I have decided to do the painting myself.
I took off the metal mounting bracket and cleaned it up. I started out by wet sanding the fender with 320 grit wet sandpaper. The paint that was left came off very easily except where it was protected from the sun right under the forks. It does look like there is a primer on it that got partly sanded off. Now it is smooth and clean and ready for paint.
[size=12]Now for the questions.[/size] What kind of paint is the best? Should I use a primer first? Is there anything else I need to do to prepare it? I've got 400 grit wet sandpaper for between coats.
I also got a pair of BMW hand guards. They are white and I'd like to paint them black or maybe yellow. What is needed to prepare very smooth and shiny plastic for painting and what kind of paint should be used?
Justin, I know you have painted motorcycles. What would you suggest? Anyone else have any ideas?
Thanks for your help!
-
You definitely do want to use primer - ideally an automotive grade paint & primer from the same company - some mfgrs chemical bases do not play nicely together, and I find the easiest way to avoid this potential issue is to use the same brand/product line. Not only will the primer help seal the part and any remaining paint from interacting with your new paint, when it goes on and dries you may possibly see "lines" where you thought you had sanded things smooth enough, but there was still a line/discontinuity -> more sanding needed! (and re-prime). Let the primer fully cure for several days before applying any color. The fully cured primer should stick well to the subsurface, and leave a clean surface for the color to stick to. I use disposable latex gloves when handling the primed parts to avoid leaving skin oils, dirt etc. on the primer surface.
I've used Rustoleum paint on bike parts in the past, but I think that I'm going to try something else, especially for plastic parts. Things seemed to get 'weird' when I used the Rusto enamel primer and semi-gloss black on my sidecovers. Justin or others can give better recomenndation. If I don't get a decent paint sprayer for my compressor first, I may try to get some Eastwood automotive paints - they used to be available in spray cans (probably still are).
You can certainly hand-sand, but you'll need to get some finer grit paper. I use 400-600 for smoothing and cleaning up runs/orange peel, and go up to 1000 for wet sanding color coats. A little Maguire's fine polishing compound maybeat the end. Are you thinking of using a clearcoat?
There are folks here who know much more about auto-painting than I do - I'm sure they'll chime in soon!
-
As you dont know the "paint History" nhmaf is right to point out you could have problems with chemical reactions even though you have sanded it down.There a a number of sealants available which you spray on before the primer consult your paint shop im sure you get good advice also if you want to go the extra mile finish the job with a protective clear lacquer(again talk to the paint shop) this will protect from Fuel/brake fluid spills ect.All these products are availiable in aerosol if you dont have any spray gear.
Lou
-
Above advice is very good.
Generally, if you prime the fender and you don't have any weird reactions with the substrate, chances are your topcoat(s) will be fine. The best paint is made at the automotive paint store, is mixed with a reducer (thinner) and has a catalyst added. It is then clearcoated with clear that is also mixed right before painting. This is difficult, expensive, and requires an air compressor and a gun, but also requires that you clean everything up. Drag.
Use a rattle can. Go to an automotive store that carries paint, and ask for help. The auto touchup spraypaint is better than regular spraypaint, has a dedicated topcoat clear, as well as primers specifically made for them. Follow the directions. Watch some how-to videos. This route is cheap, with no cleanup or waste. By the way, you shouldn't have to sand between coats of paint or clearcoat. (Unless you mess up!) Yes, sanding between coats of primer to arrive at the final perfect base is done with "wet" sandpaper, as would be any subsequent "oops" repair of paint and clear. I use 600. 400 is about right for the primer, but too aggressive for the paint/clear.
For the plastic, try Fusion by Krylon. It is for plastic specifically. A supermoto rider I ride with painted his white plastics black with it. He then crashed, repeatedly, on the track and it just scuffed up. It did not peel. Amazing. Do not paint the plastic handguards with regular black spraypaint. I don't think it will work.
What color is the bike/fender?
-
Under the seat, on top of the fender, the BMW paint code is displayed. If it is any color than non metallic black or white, call up Holt BMW in Ohio, http://www.holtbmw.com/, and see if you can order the matching color and some clear coat in rattle cans. Then wash the plastic in warm soap and water, rinse it well, and let it dry completely, then use etching primer on the bare plastic, let it dry two days, put the color on, and a couple of coats of clear. Let it dry for a week, then rub it out. With two stage paint you only lay down a thin coat of color and then put the clear over it without sanding. It will look great and match the rest of the bike.
Check out Monte's photos.
Have fun
Steve
-
My first attempt at painting boxer plastics was very dissapointing and time consuming. I used normal rattle can primer and colour matched rattle can paint from paints4u.com (uk) . Firstly wherever the primer came in contact with the plastic it bubbled up. Secondly sanding that down messed up the plastic underneath. Thirdly, the colour didn't match, cos the original paint had faded over the years.
So now, I always put on a coat or two of rattle can plastic primer first and I don't rely on the colour code to achieve a good match. That's worked fine for me since. Good luck.
-
Can you do a quality paint job with "rattle Cans" ? It's a question that's always interested me. I think you can do a pretty good job with care and patience but how durable will it be compared to the original finish. One new thing that might help is that 2 pack clear coat is now available in rattle cans. There is some sort of button on the bottom of the can which releases the catalyst and the can then has a short finite life and of course you have to use it all up or loose it. Will it be as hazarous to use as normal 2 pack ? Anybody tried it yet ?
A Google search for "2 pack clear aerosol" will find several manufacturers doing these now - here's one.
http://www.spot-ontrading.co.uk/hb-body-496-2k-ms-clear-400ml-long-life-8-p.asp
-
What color is the bike/fender?
Bike is black! Easy. I think any gloss black will do just fine. Plus, aren't these fenders fiberglass? Does that make a difference?
It doesn't have to be perfect. Just good. It seems like it should be so easy, but maybe not. There is a good paint store in the area that carries auto paint. I think car fenders and bumpers would be very similar to my fender.
I'm also going to call a place in town that does cars and motorcycles. They started out doing custom paint jobs on motorcycles and have won awards. I hope that doesn't make them more expensive. But I'll call them and if it's within reason I may just take the stuff to them to paint. All I can do is ask. ;)
I'll let you know! Thanks for all the advice.
-
I decided what to do. :)
I called the place that paints cars, motorcycles, etc., and they said a ball park figure would be $300 - $350 to paint the fender. :o No way! I'd rather do my own no matter how much trouble it is.
So, I went to the best paint store in town that carries paint for everything. These guys know what they are doing. I took the fender with me so they could see what I was painting and that I wanted to do a rattle can paint job - don't want to mess with mixing. :P He gave me the black primer and black gloss color coat and said that would be the thing to use. The primer is flexible too. He said that would work on any plastic part and that I should be able to use the same primer and color for the hand guards. I just remembered, though, that I forgot to ask about a clear coat. Darn. Now I have to drive back down there. (sigh)
I've already read the directions on the cans. ;D That is what I'm supposed to do, right? ;) Now I've just got to do some touch up sanding and cleaning of the fender and let it dry and I'll be ready to start the paint job tomorrow, unless something else comes up......................... like a ride. Hmmmmmmm.
I'll let you know how it goes and have pictures too.
-
yes, the front fender is fiberglass. DAMHIK :(
I hope you have fun, Melena!
That price you were quoted must be a California body shop!
I had my tank repaired (minor dents) and painted along with the fender for $550. And he is one of the most expensive guys in the area!
-
I don't think any pre-shop will charge less than $300 for ANYTHING - partially to keep any but the really serious away, and also becuase they do have a fair amount of setup time, prep work, and cleanup time to deal with for any job, even a small one.
I got a quote to repaint the body parts of the R65LS at a good body shop in town and it was between $550 - $700 for single colors, AND I had to bring in/buy the paint, too. They would include sanding and any light filler work if needed (it isn't). We'll see - for $700 I could buy a fair amount of beer, 2-part paint, decent spray gun, and more sandpaper for myself, too.
-
Well, I've been working on it. Got the primer on yesterday and put the black shiny coat on today. Looking good! 8-)
Now I will wait for a few days to let it dry completely. Then I have to decide weather to put a clear coat on it or just wax it really good. But first I have to check out clear coats and see exactly what the advantage is. It might have to do with hardness and imperviousness to scratches, gasoline, oil, etc.?
-
Melena, get some 400 grit wet/dry sand paper. After the paint is really good and dry then wet the sand paper and sand it down. That will put a really high gloss finish on it. Monte has a lead on some pin striping that will really accent the paint work. Send us some pix when you get it finished.
-
Melena, get some 400 grit wet/dry sand paper.After the paint is really good and dry then wet the sand paper and sand it down.That will put a really high gloss finish on it.Monte has a lead on some pin striping that will really accent the paint work.Send us some pix when you get it finished.
Thanks Mr. Phorqs! ;) (I've met a person from Sweden named Bengt, so when you showed up I thought that was actually your name! ;D Hmmm, I'd better be careful here. It might be your middle name.)
I have that sandpaper already. I'll give that a try and see what happens. I'm learning as I go here. So far so good!
So I'm guessing that I'll do the wet sanding, clean it up and then put on a couple coats of wax? I've got Mother's Carnuba wax that I've used on the other shiny bits of the bike.
It doesn't have to be perfect. Good enough is good enough. 8-)
-
Monte has a lead on some pin striping that will really accent the paint work.
I've been looking to replace some pin stripes on my seat cowl. I found some 3M tape at Pep Boys that looks adequate, but sure would like to get some advice from experienced hands.
-
Well, I've been working on it. Got the primer on yesterday and put the black shiny coat on today. Looking good! 8-)
Now I will wait for a few days to let it dry completely. Then I have to decide weather to put a clear coat on it or just wax it really good. But first I have to check out clear coats and see exactly what the advantage is. It might have to do with hardness and imperviousness to scratches, gasoline, oil, etc.?
You're almost home, Melena. You did not mention how many coats of color you shot but 3-4 would be time well spent.
After the paint has cured for a few days and before you even think about rattle can clear... try this suggestion. Visit a local auto body supply shop and purchase a few sheets of 800 grit wet-or-dri paper. Also buy a small, flexible rubber sanding pad. 3M makes 'em. Black firm foam and approx 2.5x4 inches.
Cut the 800 into usable sizes and toss 'em in a bucket of water. Use the 800 and the foam pad to color sand the cured paint. Long, parallel strokes. Caution on edges as you can easily cut through the paint.
After the color sanding, use a mild polish and then wax the previously cured paint. Cured is impotent, right? You can then forget about a clear coat.
I rattled-canned the side panels on the 1981 R65, then color sanded, polished and waxed. Couple years now and they still shine like the proverbial diamond in a billy goat's butt.
Monte
-
Thanks for that info Monte!
I think I have 3 coats on it. Maybe 4 in some places. The directions on the can said 2 coats, but I didn't think that was enough.
I'll give it a good wet sanding like you said. I have 600 grit wet/dry. Will that be okay? I haven't been able to find anything finer yet. I'll see how the sanding does. I can always add another coat of paint if the 600 is too coarse. But I will go find one of those rubber sanding pads. I guess that would be more consistent than my fingers.
It almost looks good enough like it is. [smiley=happy.gif] Well, almost good enough.
Tomorrow I will continue on to the next stage. 8-)
-
Hi Melena,
Hopefully you'll catch this before you wet sand your fender...from my own experience (I've painted the fairing on my LS as well as one car) you don't want to sand your paint with anything coarser than 1000 (even with that it's very easy to sand through the paint). I would go for 2000, yes it will take a bit longer but the results will be great (it will remove all the orange peel). Also depending on the type of paint you got you should wait before waxing. For example if you're using a rattle can acrylic enamel (single stage paint) you should wait at least 30 days for all the solvents to evaporate (obviously less if your paint is catalyzed).
Hope this helps
Luis
-
Depending on the paint you used, if it is smooth and shiny, and you like the way it looks now, just leave it alone and wax it in no less than two weeks. A month would be better. Paint take a really long time to fully harden, even up in warm and sunny Sonoma.
If it has runs and or orange peel, then sand it and put on another coat. Clear coat is never a bad idea but with non metallic black shouldn't be necessary.
Steve
-
Great info guys! Thank you. Glad I looked at this before I did anything today. I will go find some 2000 wet/dry sandpaper.
I'll be going up to the MOA Rally in Redmond in less than 30 days, so no wax before then. I can always sand it a bit and add another coat of paint if it gets nicked or scratched on the ride.
-
Regarding using 1000 or 2000 grit wet/dry....I've been wondering if one should use this on a final base coat prior to applying the first clear coat or is this too fine to get good adhesion?
-
The finest stuff that I've used with hand-sanding is 1200 grit wet/dry, which is pretty good, I think. Any finer polishing needs I tend to do with some automotive polishing compound like they use with the rotary buffers. I think that you'd be OK with sanding with 1000 or higher and then clear-coating, at least I haven't had issues with clearcoat yet.
-
I've been looking to replace some pin stripes on my seat cowl. I found some 3M tape at Pep Boys that looks adequate, but sure would like to get some advice from experienced hands.
Something like this? The tape's sizes and spacing is very close to the OEM BMW paint striping. Positioning is as stock.
I did both the tank and tail piece in the original R65 layout. The 1983 bike is 501 blue. I had originally considered white stripping but it looked rather garish to me. The final choice of silver offers a subdued look. I feel the color adds an elegant touch without too much "bling". Certainly does a fine job of defining the R65's snazzy fuel tank.
I ustacould run a sword striper brush and a can of 1-Shot fairly well but it's a skill that has to be practiced often to maintain proficiency.
I have been lead to believe that it was a squadron -staffel?- of women that laid on the paint stripes at the BMW factory.
Monte
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi196.photobucket.com%2Falbums%2Faa1%2Fmontmil%2FBMW%2520R65%2FP6240016.jpg&hash=aa26fc8b2ef6f0a2cc5299945255884b92a90d00)
-
It looks beautiful, Monte. Did R65's have a double stripe?
Now I have to compare mine to yours. Mine is sitting on top of one of my stereo speakers, waiting for me to buy a 2nd gen. bench seat on which to put it.
-
It looks beautiful, Monte. Did R65's have a double stripe?
Oh, yes, quite right. My 1981 R65 is still dressed in its original colors; black with a white and red pinstripes on the fuel tank and tailpiece. Although the stripping is buffed nearly off the fuel tank in the knee grip area, it's a touchstone from three decades ago. I would not have the heart to repaint the bike.
Monte
-
Good to know that you can get such nice results from the tape.
My '82 has the hand-painted red and white stripes on the tank. I'm not sure that it is the original black, as there seems to be a layer of red underneath everything that chips or scratches. Tape was used for everything else and I mean everything -red and white stripes on the seat cowl, the front fender, the back fender, the side covers, the BMW bags and on the black plastic all 4 turn signals. A little much, even for me whose motto is "Anything worth doing is worth overdoing." I guess when the PO bought the striping tape, he decided to darn well use up as much as he could. ;D
-
The original factory painted pinstripes on my 1982 R65 were applied using the maskind tape method. You can tell by their raised edges. It is quite easy to produce a job of equal quality using a quality plastic insulation tape( it will stretch nicely to accomodate the curves required and the paint won't run under the tape). A couple of squirts from the rattle can will then do the job. Good luck
-
Monte,
Did you have to clear coat over the tape or are they durable if applied on top of the clear coat ?
-
Monte,
Did you have to clear coat over the tape or are they durable if applied on top of the clear coat ?
On a clean, wax free surface, this stuff sticks tighter than a tick. I have used this type of tape on several different projects; my personal aircraft (2), automotive and now motorcycle. No clear coat.
Also, my wife's new Cadillac DeVille has subtle OEM vinyl striping on top of the clear coat paint.
Don't want to get too far off this "paint" topic but if there's interest I'd start a fresh thread on tape application, tight turns, etc.
Monte
-
I'd be interested in that info Monte.
-
I'd be interested in that info Monte.
+1 I'd be interested, too. My tank is in dire need of a repaint, and I've been wondering about the pinstripes.
-
OK. Soonest but grandkids will be here Saturday morning until Monday.
Monte