Classic & Vintage - Tell me about spraying

I'm almost down to bare metal on a frame I'm doing for my son. After that, I'll be ready to spray. I know I need undercoat, and to layer it up (I'm rattle-canning). How should I support the frame while spraying, what do you guys do about overspray, and what other tips are there?

The last bike I painted, I used the stand from an old floor lamp, and placed the seat tube over it. That way I could get full coverage without having to handle the frame. I was outside on the leeward side of the house, so I didn't worry about the overspray.
The other tip is to let the paint harden for at least a week, or even 2, before putting parts back on. While the paint may be dry enough to handle after an hour, it is still very soft and scratches VERY easily.

I "suspend" mine using coat hangers thru the seat post bolt hole and the head tube, or the rear drop outs. I also use one of these can handles (http://www.makezine.com/pub/tool/Spray_Can_Trigger_Handle) to keep from hurting my finger and screwing up the spray pattern. Other than that just take it light and easy, build up coats, spray in a flat sweep parallel to the frame and stop the spray past it. I have rattled canned quite a few bikes over the years with varying results.:p

Aaron:)

http://www.makezine.com/images/tools/sprayhandle.jpg

Dam...I saw the title and thought you were talking about nitrous oxide.




---only imports need spray---

And I thought you were talking about amyl nitrate...

Better than talking about an ill-adjusted cat. :p

Make sure you have a paint that has a very hard, durable finish. When I sprayed my Raleigh Professional (now in the much more capable hands of a skilled professional - Dr D.), I found that the paint I had selected for the top coat - even after waiting a couple weeks - could be rubbed off with firm pressure using my thumb (and not the nail).

I hung my frame with a coat hanger as well. The trigger "gun" for the rattle can is nice too. I errored on the side of underspraying to avoid runs. You can do a good job with a rattle can if you take your time, put on lots of thin layers and sand between coats. A warmer temp while you are spraying is good, it helps adhesion. Let it harden or cure for a couple of weeks before building up. I like to use a hairdryer to help speed up the process.

Multiple light coats; wet sand with very fine grit between coats; Finish with clear.

I paint outside too,but use auto paint in a sprayer.I use a piece of re-bar hammered into the ground.I let the frame hang by the headtube.I always start with the frame up-side-down then flip holding to the bb&headtube.Be sure to spray the back of the seat tube--that seems to ba a place that's hard to get at.
An even better stand would be a seatpost welded at an angle to the bar---that way you could flip the frame without too much trouble.

I "suspend" mine using coat hangers thru the seat post bolt hole and the head tube, or the rear drop outs. I also use one of these can handles (http://www.makezine.com/pub/tool/Spray_Can_Trigger_Handle) to keep from hurting my finger and screwing up the spray pattern. Other than that just take it light and easy, build up coats, spray in a flat sweep parallel to the frame and stop the spray past it. I have rattled canned quite a few bikes over the years with varying results.:p

Aaron:)

http://www.makezine.com/images/tools/sprayhandle.jpg


I use the same setup. Those triggers really help to get an even spray. I hang the frame and fork from the garage door spring and set up a couple of bicycle boxes I've opened up as "walls" to prevent overspray from covering stuff in the garage(there always seems to be a breeze on painting day).

I walk around the frame, spraying lots of light coats. After spraying on the primer, and letting it dry for at least a day, I'll wet sand with a 800 or 1000grit sandpaper. I then use a tack cloth soaked in alcohol to wipe down the frame and to speed drying.

I then paint the same way I primed; lots of thin coats. I go round and round the frame, shaking the can often. Not getting the spray can too close but not so far away most the paint misses the frame. I let the frame sit for a day or so then wet sand, wipe down, dry completely, and spray another can of paint on it.

I now have the patience to let the frame sit for a good while before adding the clearcoat. I add the decals first, then the clearcoat to seal them in. Lots of light coats as before.

After painting, hang the frame out of the way somewhere and forget about it. Start ordering parts for it or begin another project. It seems to take forever for the paint/clearcoat to harden. I suppose I could put a couple of space heaters in a closet and make it an oven. ;)

IIRC, I think Dr D posted a pretty good tutorial, check in the archives.

The best advice is to be patient, if you hurry or try to cut corners (especially in drying time) it will be reflected by the paint.

I would suggest starting in a hard area like the seat cluster/rear brake bridge, you are less likely to get drips if you do the hard areas all at once. The long tubes are easy to get an even coat. Always try to keep a wet front, overspray will be less of an issue. I also use coat hangers to hang from the ceiling.

Just an FYI from experience..

direct sun after painting=bad

I helped my brother paint a frame and we put it in the sun thinking it would help the paint dry faster..nope, ended up splitting the paint from the metal expanding underneath.


On another note, what do you all use to strip a frame? paint stripper? Wire wheel? Grinder? Sandpaper and sanding block?

Just an FYI from experience..

direct sun after painting=bad

I helped my brother paint a frame and we put it in the sun thinking it would help the paint dry faster..nope, ended up splitting the paint from the metal expanding underneath.


On another note, what do you all use to strip a frame? paint stripper? Wire wheel? Grinder? Sandpaper and sanding block?


Must have been a rare occurrence, I've never once had that happen? Weird.,,,,BD

I use a razor blade to remove decals then some 80-120 grit sandpaper to tear into the paint. Kleen-Strip stripper that sprays on gooey works pretty well. I get that off with a wire brush and paint scraper. Stripper gets applied 3-4 times then it's sandpaper and small wire brushes into the tight areas.

I got my Peugeot, Raleight Ltd., and the JC Penney frame completely stripped. This Raleigh Sprite had some really tough paint on it so I finally just left it alone after sanding it with 400 grit paper. I used a solvent soaked rag to wipe all the paint, grit, stripper, fingerprint oils off the frame before priming.

Before
http://gallery.mac.com/bbattle/100083/100_0385/web.jpg

Primer stage
http://gallery.mac.com/bbattle/100083/100_0537/web.jpg

First coat of paint stage
http://gallery.mac.com/bbattle/100083/100_0540/web.jpg

headbadge under tape
http://gallery.mac.com/bbattle/100083/100_0541/web.jpg

http://gallery.mac.com/bbattle/100083/100_0545/web.jpg

Wow! Does spray laquer from Rustoleum really fly all over the place. Seems a lot "wetter" than the other paints I've tried(rustoleum enamel, Krylon enamel, Duplicolor laquer).
http://gallery.mac.com/bbattle/100083/100_0548/web.jpg

Link to lots more pics of the Sprite, including a lot of components that are looking for a good home, all they need is a bus ticket. (http://gallery.mac.com/bbattle#100083&view=grid&bgcolor=black&sel=28)

something that has not been mentioned yet (i think)that is important to for the paint to stick to the metal is to roughen up the metal for the primer to stick... either with some rough grit sand paper or some steel wool.

Something else to do for prep is to put a thin layer of grease on the threaded parts that might get sprayed, as well as the inside of the head tube and top of seat tube. With that layer of grease as a foundation, you'll be able to wipe off any overspray with just a rag. And overspray will give you problems when reinstalling the bottom bracket, headset, and seatpost. I also use that grease trick on headbadges; it's much easier to get edges right with grease on your finger tip than with tape masking.

On the other hand, now that I have a local powder coater who charges $50 for bead blasting and a single color, I've given up home spraying!

Neal

And I thought you were talking about amyl nitrate...

And I thought you were talking about taco bell

On the other hand, now that I have a local powder coater who charges $50 for bead blasting and a single color, I've given up home spraying!
Neal

That's a really good price!!!
What shop is it?
Do you have pics of their results?

I have an aluminum 7005 welded ATB frame that I'd like to restore. It was ball burnish finished, but I have found too many deep scratches to keep it a nude finish. I'm considering powdercoat. But wonder if the baking will weaken/anneal the aluminum?

I'd be quite happy to get my Raleigh 20 powder coated, but it just doesn't feel like the right approach for a vintage Holdsworth.

I'd be quite happy to get my Raleigh 20 powder coated, but it just doesn't feel like the right approach for a vintage Holdsworth.

I have the same dilemma with some of my vintage frames with serious aged patina, but I also don't quite think that my talents as a backyard spray-can artist feel right either. Oh well, guess they'll wear the patina with pride for awhile longer.

Neal

Sammyboy.
the best way I have found to suport a frame for spraying is to clamp a broom handle in a Black & Decker workmate let the head of the broom rest on the floor as it makes it more stable, slide the headtube of the frame over the broom handle and use a set of mole-grips clamped to the broom handle to adjust the height. You can also slide the seat-tube onto the broom handle to give different angles to ensure full coverage.

suspend it under or through the seatpost bolt-hole with fishing line- wont bend or break, and is too thin to notice any unpainted area. loop it through twice with 30lb line, no bike will snap that. and if you cant reach all the way around the frame, you can easily spin it around, unlike coat hangers or anything stiff like that.

plus having an apparently floating bike frame is kinda cool.

Toss your spray can in a sink full of warm water to heat it up before spraying. Goes on smoother.