4Rings6Stars

I'm building a bike for my girlfriend for Christmas. It is an 80's Cannondale that had been spray painted by the PO and I plan to build it up with a full 8s tricolor STI group (harvested from my Merckx, which will be wearing Campy by the new year I hope). She has been doing some commuting and has decided that next summer she wants to do some longer rides with me so I want her to have a proper bike.

She picked up one of my titanium bikes a couple weeks ago and then gave me a bunch of crap because it weighs literally half as much as her hybrid so I feel its only fair that she has a nice lightweight bike too.

Anyway, I plan on painting it purple (she mentioned at some point how sweet it would be to have a purple bike and I took a mental note). I was going to get it powder coated but then decided I would do it myself. I considered spray paint with careful prepping and clearcoating and considered exterior house paint and a brush. Then I remembered my brother has an air compressor and spray gun that he has never used...I'm going to get some automotive paint and give it a try.

Anybody have any experience doing such a thing?

I'll keep this thread updated, but for now here is how the frame sits. It's just asking to be painted purple, I can't stand the color combination on it now though the guy did a pretty good job with a rattle can.

realestvin7

Rattle can all the way. I'm building a bike for my girlfriend for Christmas as well. It's a '78 Raleigh Grand Prix. I will be painting it 3 colors. 1 color for the main tubes, 1 for the lug work, and 1 for the seat tube. It's going to look great I think. Just be glad you don't have lug work to tape off. Lol.

As for spray painting, prep work is very important. Be sure to sand well, and invest in some prep cleaning solution. You can use a mild soap and water if you want to stay on the cheap. Thoroughly dry the frame, carefully tape off what you don't want painted, and go to town. I recommend using dark gray Rustoleum auto primer since you're going with purple. As for spray paint, stick with Rustoleum as well. For masking tape I recommend green "Frog Tape", which can be purchased at any home improvement store. Another good choice for tape is green 3M automotive masking tape. To finish it off, grab some Duplicolor wheel clear coat from an automotive parts store. We've used it on our spray painted drift spares and it seems to hold up to chipping and scratches very well compared to other spray can clears.

Be sure to keep us in the loop and show off the work.

WNG

Given her choice of color, may I make a suggestion?
I was going to save this finish secret for myself and present it in the before/after thread...
It's a rattle can spray that simulates anodized metal. Sort of like a candy, chromovelato finish. It's from Krylon and I've found it in red, blue and PURPLE.
You spray it directly on bare metal. If you strip the Cannondale and polish it up, it should shine through the purple layer really well.

Here is a sample of how it looks in blue. I experimented on a steel Specialized stem. I wire-wheeled the steel before hitting it with 2 coats. It looks quite close to an anodized aluminum surface.

randyjawa 

Spray painting with a rattle can, or even a professional spray gun, is not as easy as one might think. Overspray can be a problem, when attempting to spray paint a bicycle frame. Over spray onto everything else in the room, as the spray settles. And, over spray on the tubes of the bicycle. It is tough to spray one tube just right without having over spray hit another tube.

Painting with a brush is cheap, can be done anywhere and gives pretty decent results, if you take your time. If you want to see how I Paint Bicycles With a Brush, have a look at my PX10.

Hope this is a help.

realestvin7

Nice job! Now I gotta check into this. Thanks for posting.

toytech

you can get real automotive paint and clear coat in spray cans from a paint shop, a little practice and a lot of prep can yield professional results. A respirator will be mandatory though, especially for the clear.

4Rings6Stars

Thanks for the suggestion guys.

Randy, I read through your painting article and didn't notice (may have missed it) any mention of how to protect threads, bb face, etc. Just carefully mask these areas off with tape? Might get a little tricky with water bottle brazeons and the front dérailleur brazen unique to these 'dales.

Do you think I need to entirely remove the paint to have good results or would sanding well and priming suffice?

Also, anything from your article that you think would be different because this frame is aluminum?
Thanks!

Wogster

Like any other painting job, PREPARATION is the key, it's not uncommon on many painting jobs to take 10 hours of preparation and 1 hour of painting. First you need a good assessment of the existing paint, one problem with paint is that it builds up, you need to make sure that there are not too many layers on there already, you also need to make sure there is NO rust anywhere, and no dents in the frame, you also need to make sure you fill in any nicks, deep scratches and chips so that the surface is nice and even. Make sure the frame is totally clean, anything like grease or oil, even in trace amounts can kill your paint job. Next you need to mask off the BB and headset, you could remove the external parts of the headset, then mask off the rest. Give the existing paint a good sanding to give it a rough surface for the new paint to adhere to. Go over it with a tack cloth to remove any dust, do this again just before painting. Remember that ANY imperfection in the surface will show through the finished paint (this is the problem with many rattle can paint jobs, they don't prep anywhere near enough). If you know the model and year of the bike, see if you can get a set of original or reproduction decals to finish it off.

Really consider the difficulties of spraying paint, bicycle tubes are hard to spray well, so consider Rand's brush technique, especially in a city like Boston, this time of year when you need to work indoors under central heating.

4Rings6Stars

Good advice in here, thanks. I think I am going to try Randy's method. I had considered it but thought it would yield a sub par result. After reading through his write-up and looking at pictures of his PX10, I see that with prep and careful attention to detail and can produce a very nice result.

randyjawa 

It matters not if you are painting the bicycle with a brush or top of the line spray equipment in a professional facility. Surface preparation is step one to getting good results. If there is a ripple, scratch, scuff or what ever to interrupt the surface before the paint goes on, then it will likely be visible after. So, the smoother and cleaner the starting surface the better. That said...

In my book, if the paint has been there for a bunch of years and has adhered well to the frame set, showing no signs of cracking, crazing or the like, why not leave it. Of course, the really smooth surface still applies. The edges of the old paint must smooth, seamlessly, into the metal.

Also, allowing coats of paint to build up helps to remove frame feature definition. In other words, your lugs might not meet the tubes with a nice crisp look.

And that goes for between coats also. Always fine sand between coats and then thoroughly clean the sanded debris away.

When it comes to protecting bottom bracket threads, etc. I simple exercise caution around these areas. As for separating lug work from tubing, that is an exercise in getting it right masking. Actually, it is not difficult, but care, once again, will produce the best results. And, once masked, do not start wailing away with the brush. Always drag away from a masked edge.

Remember, the entire process allows for error, sort of. As you apply each coat, you get better at it. I suppose, if you kept at it long enough, sanding between coats, you could achieve perfection.

As for painting aluminum, the one big difference, for me, would be that I am working with a softer material. I would not clean the frame set as aggressively as I would, were it steel. Finer grit sand paper. Extreme care with machine driven hand tools. Careful consideration, if you intend to use chemical stripper - ugggg! A caustic based one will eat at aluminum alloy. Try painting something that ain't there. I could tell you all a funny story about caustic and stripper. Just be careful!

Hope this is a help.

4Rings6Stars

Well the bike is pretty much ready to build. Just a couple more coats of clear and I will start the build.

Here is the progress (sorry only crappy iphone pictures until I find my camera charger!!!)

Mostly sanded down. Looks like the frame started its life black, hopefully it wasn't a BL... Sanding was a PITA but I found 80 grit to work pretty well...


After a few coats of primer.


First coat of paint.


After the first clear coat.


I'll get some proper pics up of the final project but I'm exhausted. Lots of late nights this week after she went to sleep to keep this project a secret and have it for her on Christmas morning. She LOVES it.

realestvin7

What kind of paint did you end up using?