Robvolz 

I keep finding Cinelli and 3TTT stems in black with visible damage. Maybe they were allowed to slam and that created a silver ring where no ring belongs, or maybe unlike silver, they can't be buffed or at least re-anodised as easy.

I have found some really fun Panto'd stems in black, from Colnago, DeRosa and even local companies, Davidson and Strawberry. But, they are scratched to heck.

The black stems aren't anodized. Are they powder coated? Dipped? How does one protect the panto? Fill in with wax to remove later or just re-run your Dremel along the recessed parts and hope to not slip?

What successes have people had, what are your tips?

As always, thank you
Robert
Portland

wschruba

They were likely powder coated/painted, depending on the origin of the "manufacturer". You can tell--if you're okay with sacrificing the finish--by painting some Citrustrip on the bottom where the wedge pulls. If it bubbles/flakes off after a few hours, it's paint. If it laughs at you, it's powder (or anodizing).

How complicated is the pantograph? Usually, you would just strip the entire stem, and re-paint it. I had one frame/fork/stem/seatpost that we sent to Spectrum for a repaint, and that's what they did.

If there's no damage to the areas that are pantographed, mask them off, *find a color match first*, mechanically remove the damaged areas, or feather them out, according to your skill/paint match, then build them back up with your new stuff. Feathering in repairs takes a modicum of attention to detail, but mostly being okay with the fact that it is going to take several hours to feather in a repair that doesn't look like a repair.

dedhed

Sharpie

canklecat

Look for a spray & bake finish. Gun Kote and others make 'em. Results vary. It worked great to restore the finish on some older Crosman and Daisy pellet guns made of mostly cast zinc that seemed to use an essentially identical spray and bake finish originally. I also tried it on a stainless steel knife but the finish wore quickly. However it didn't chip or flake. The finish just wore down from friction cutting cardboard boxes, etc. But that's probably beyond the intended specs for such a finish. For a bicycle stem, seat post, etc., it should work just fine.

As long as it can withstand a moderate oven heat (325F for an hour) it'll be safe to use. Most user anecdotes about techniques and results will be found on gun forums. That's a fairly hard usage so if it works on firearms, it'll work on bike components as long as the metal can safely be heated as recommended by the spray finish maker.

There's also Cerakote. I've never used it, can't offer any recommendations. But some folks say it works well.

And de-burr the mating surfaces in the headset, lock rings, etc., to reduce the risk of scratching the finish again.

Schweinhund

When refinishing a stem, no matter the method used, be aware that all coatings will add to the circumference of the quill.
You may be going from bad to worse as far as scratching goes.

lorica 

I have restored all sorts of black anodized parts including stems, crank arms, pedal cages, seatposts, etc. with Birchwood Casey Aluminum Black. I clean the area to be treated with isopropyl alcohol and apply this amazing stuff with small or larger swabs, let it sit and thenwipe off excess.. Multiple coats are often needed but the results can be near perfect. You only need to apply to the scratched area so no need to protect the pantos. It seems to smoothen the scratch but does not add to the circumference. I've even used it for small chips on black painted or coated items with good results.

My Amazon account shows I've ordered 6 over the years.
https://www.amazon.com/BW-Casey-Alum...3323315&sr=8-6

In addition to the liquid, they have pens that are also useful in some situations.

Robvolz 

wow, never heard of the product. I watch a video where a guy had a knife with a black aluminum body, with worn spots. The liquid is clear. After 3 coats, the handle was an even flat black.

However, my quill stems aren't flat black, but satin or semi-gloss.

still, I see using this on some modello brakes, a super record front derailleur, etc.

Thanks for the tip.

plonz 

This Sameness steel stem was in rough shape. I sanded it down to bare metal and did a couple coats of primer, color and clear. The fresh paint on the length of quill that got inserted did not hold up at all. The visible portion has held up quite well, even with a computer mounted to it.

bwilli88 

Sanding to smooth and prime then spray paint.

Mr. 66

I sanded off the black and polished the last Nitto

Miele Man

I hand sanded and polished a silver stem then painted it black with KRYLON spray paint. It held up quite well. I also used the same black KRYLON paint to paint aero brake levers for another bike and t hose too held up quite well.


Cheers
Here's an image of the bike with the black KRYLON spray painted stem.

lorica 

I've used it mainly on items that had some sheen / gloss and ended up with an excellent blend. Often I can't even tell there was ever a scratch. If you buff it when wiping off, it comes to a luster. The more you buff, the higher the luster, If you want a matte finish, you don't buff. It's always worked very well on black stems. I believe the smoothness of the surface makes a difference.