After searching high and low for a chemical that would attack the anodizing(?) on these Paul Thumbies, I threw in the towel and went mechanical removal. The closest I got was a sulfuric acid solution at about 10% which ate the steel roll pins holding the two halves of the Thumbies together and 'kind of' attacked the surface of the black anodization.

Come to think if it, I think the black treatment from Paul is more like a thick powder coating. I tried at least 6 different chemicals IIRC. The sulfuric acid reduced the luster of the black powder coating and that was about it. A dremel and wire wheels, 120 grit, 320 grit then scouring pad. Definitely not the best, most beautiful finish. However, the porous finish I put on here (inadvertently) will likely work in my favor when I go to etch then anodize. I left the aluminum alone after the wire wheel on both the surfaces which mount to the bars and where mounting to the shifters.

To recap, with the right chemical, this process is about a half hour and the aluminum is left just like Paul milled it before anodizing. Removing mechanically and sanding takes about three hours and the surfaces are left sub-factory standard. Shart happens! I would also postulate that Paul parts that are not clean enough for anodizing are powder coated black, because the powder coating layer is quite thick and these had particular thumbies had a few blemishes I discovered.

A little before and after and I'll fill in the logos with paint before anodizing:

3O1F4742.JPG 3O1F4744.JPG

120 grit, 320 grit then scouring pad:
3O1F4745.JPG
3O1F4746.JPG
 
damn, looks like all of that effort has paid off for you, rad. I know you're stoked on the stem, but I love the chainrings!

Seatpost: size and budget? 200 euros? I got lucky and paid about 120 euros for mine. I believe standard length is 350 mm so anything shorter than that has been cut or a special order. Last I talked to Schmolke in person, he charges 1 to 1.50 euro per mm depending on standard tubing or TLO tubing :eek:
Yikes! 27.2, on the shorter side, for a road bike ;D If you come across one for less than 1 euro per mm let me know =]
 
Small update with anodizing.

I am currently visiting family in the USA. Since I have been on a wild goose chase these last few months in Germany looking for a proper chemical, I brought my Paul Thumbies with me in my luggage to experiment over here. Went to ACE hardware and bought a few bottles of Whink Rust Remover which has about 2% hydroflouric acid solution.

Dropped the thumbies in the solution and about two minutes later all remaining anodization was eaten off. A complete success at only $6. Plus the solution is reusable.

At the very least, these parts are ready for color anodization when I get back to Europe in a few weeks along with some other small goodies I will bring with.

Before:

18060F99-C1BD-4ECA-A90F-E91E9E00429B.jpeg

After:
E5DB8CB5-CAC7-4355-8FC1-BEC7FBF32EBF.jpeg 91B8B97D-874B-4AC3-A339-35A949AD4150.jpeg
 
Small update with anodizing.

I am currently visiting family in the USA. Since I have been on a wild goose chase these last few months in Germany looking for a proper chemical, I brought my Paul Thumbies with me in my luggage to experiment over here. Went to ACE hardware and bought a few bottles of Whink Rust Remover which has about 2% hydroflouric acid solution.

Dropped the thumbies in the solution and about two minutes later all remaining anodization was eaten off. A complete success at only $6. Plus the solution is reusable.

At the very least, these parts are ready for color anodization when I get back to Europe in a few weeks along with some other small goodies I will bring with.
Great work! 💪👍

Any chance you can bring any of the stuff back with you? I would 100% be trying to work out a way, but guess you could land yourself in big trouble?! And no doubt my comment will trigger off some people on here! 😜🤣
 
A bit hard to tell in the photos, but the rust remover completely removed all the remaining black anodization and whatever oils were on the surface.

sweet progress! can't wait to see what color those end up.
Thanks man! Maybe green, maybe turquoise, maybe purple.

Great work! 💪👍

Any chance you can bring any of the stuff back with you? I would 100% be trying to work out a way, but guess you could land yourself in big trouble?! And no doubt my comment will trigger off some people on here! 😜🤣
Thank you! Regarding transport: We’ll see what happens in a few weeks!
 
Great work! 💪👍

Any chance you can bring any of the stuff back with you? I would 100% be trying to work out a way, but guess you could land yourself in big trouble?! And no doubt my comment will trigger off some people on here! 😜🤣
Hydrofluric acid? Isn’t that the stuff they dissolve the bodies with in Breaking Bad? 😬
 
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