Tuesday, January 24, 2006

mmm copper

More coppery goodness occurred last night. I put a few coats of clear on the whole frame after plating it the previous night. Considering how skeptical I was about doing this finish, I really love how it came out. I've had a few folks ask how I did this. I used a copper sulfate solution to create the plating effect. The surface needs to be prepped extensively though for this to work, it needs to be cleaner than you can imagine and had a consisent suface finish. I acid etched the steel to help prevent corrosion and remove an oils left from my hands, then sprayed on the sufate. Finally once it's completely dried, I cleared over it with a lacquer.

This is my favorite shot. The headtube came out all marbled and cool. As the future owner said: "it looks like mahogany!"

The plating solution just naturally darkens around the edges of the cutouts and lugs, which really highlights the fanciness of the lugs!

To get the logo on the downtube, I used a vinyl paint mask on the bare steel, then acid etched and darkened the lettering, removed the paint mask and plated the copper over the darkened area. I honestly had no idea how this would come out. The result is an antique-looking logo that I think fits in perfectly with the rest of the finish.

This second nature bike has been a long time on the making due to lots of factors. It sure feels great to see it almost done and to see how spectacular the finished result is looking. This frame is an anniversary gift for one lucky lady in New York, so she has no idea what it looks like yet. I sure how she's as thrilled with it as I am to have made it. This has been a really fun process.

The husband who is giving the gift has really been pushing me to show this off at the Frambuilder's show in San Jose in March. And I've really been tempted to go since I happen to have 4-5 really unique frames in the shop right now. The downside is that I'm swamped with work right now and I don't realistically think I'll be able to take the time and money for ship 5 frames to CA, fly out there and display them. I guess it's just not in the cards for me this year. Maybe next year though if I can plan ahead better!



Anonymous said...


Did you apply current to the frame? IS it truly plated, electrophoretically, not just spray patinaed?

I've been in the plating biz for a long time and we've missed this spray finish. If it's not too much trouble please let me know where it came from.

Bruce Masterson
Technic, Inc.



Bob said...

That's an excellent question Bruce, I'm certainly no plating expert, so I can't say if it's truly "plated" or coated or whatever. The techique I used is appearantly pretty well known in the decorative metal finishing world as I found tons of info about it on-line in decorative finishing forums, it is appearantly called "immersion plating".
The solution is a copper sulfate as I said and it requires no electrical current. You basically just wipe spray or immerse the bare steel into the copper solution. The steel is less noble than the copper, causing to to come out of solution and bond to the steel. Unfortunately the reaction stops as soon as the steel is covered, so you essentially end up with a coating 1 atom thick.

Maybe this is considered spray patina in the business and I'm using the wrong terminology?

Thanks for the comments Bruce.


Frostbike said...

That bike is beautiful. I hope you can post pictures of it built up too.

Anonymous said...

Thanks Bob. There is a branch of products called Electroless and the aother called immersion. I'll have to do more homework. It's not the area we beal in obviously but what a nice finish.

If you ever want to experiment with other finishes I'd love to hear about it.

Best regards,

Bruce Masterson