webike4fun

I recently spoke with a bike shop owner in the Orange County area about a nice frame that was "repainted" using the powder coating process. His remarks were the frame will ride "dead" as the Columbus SL tubes are thin enough and sensitive enough to react to the process? Ok I need everyone's .02

bikemig 

Since the bike has been "deadened" by the repaint, do the bike shop owner a favor and let him give you the "dead" bike. You can report back in a few years whether you think he's right or not.

cyclotoine

react to the process? Never ever ever have I heard anyone in the frame building world say anything about powder coating affecting the grain structure of the steel alloy.

Also, I think that people on the forum should be aware that bike shop owners are regular people and probably more than half of them know half as much as more than half of us. I constantly here people say "well at the bike shop they said..." and all I can do is roll my eyes and advise them that they are being fed some old bike lore or myth that simply isn't true.

WNG

LOL! Thanks I got my good chuckle for today!

There is nothing in the process of powdercoating that can 'deaden' the steel frame. One can possibly damage the brazing of a brazed frame if it was improperly sand-blasted as prep. The baking process temperature is way lower than that from the brazing torch.

etherhuffer 

There is one slight drawback to powdercoat. If you have any engraved logos, like the top of my fork crown where it has molded in "Fuji" then paint looks better. Powder tends to fill in the lettering so you can't see it. If I had a cool rare bike with lots of logo work I would use paint.

Kactus

I suspect that what the owner was trying to say is that the thickness of the coating will affect the stiffness and vibrational dynamics of the frame, not the physical structure of the steel itself, i.e: you could place a 1/2" thick fiberglass resin around the entire frame and while not affecting the steels properties it certainly would ride differently. Now whether or not the powder coat is thick enough and stiff enough to make a discernible difference in the bikes ride quality I have no idea but seriously doubt many, if any, people would notice a difference.

If you like the frame and it's reasonably priced I wouldn't worry about it!

Lascauxcaveman 

B-b-b-but a powder coat finish can weigh as much as 1/8 oz more than a standard paint job, if applied in exactly the right way...

WNG

The OP stated the shop owner referred to the 'process', not the perceived thickness of the powdercoat, which is still much much less than the thickness of the steel.

Michael Angelo 

Unless they fill the frame with powder coat....

Kobe 

Wouldn't that make it powder underwear?

Hudson308 

I recently had three frames powdercoated with a two-step effect that uses a solid base color followed by a chameleon (color-shifting) "metalflake". This likely results in a thicker coating than you would get with a single solid color, so I was curious to see how much weigh it would add to a 56cm frame. The frame coating added 1.28oz (36.3g), and the fork coating added 0.32oz (9.1g). Total weight added was 1.6oz (45.4g). It would be interesting to compare that with a typical paint job. There was no discernable change in ride characteristics. My local powdercoater uses a 400 deg. (f) industrial oven for the process. The powder did fill in shallower bits of the serial number, and softened some embossed detail. Overall I'm very happy with the results.

jimmuller 

"And I like less than half of [them] half as much as [they] deserve..."
The shop owner could have used "process" for the general concept, not drawing a distinction between the process and the final result. But it still doesn't make him right (or wrong).

I dropped into when I saw the words "orange" and "powder coating" in the same sentence. Then I figured, naw, I posted those pics elsewhere just a day or two ago so I won't subject anyone to them again.

Michael Angelo 

I just painted a frame it took 9 coats of paint, including sealer etchers, primers, base primers color base and clears. Feels perfect to me....

16Victor

Heretic

I reckon that powdercoating *might* affect the dynamic response of the frame by altering its resonant frequency...thus maybe affecting feel. I'm stacking a maybe on top of a might so I'm not certain it'd have much affect.

Any change in strength would be negligible.

irwin7638

I've heard of that, but haven't seen the problem with two different brand frames.


Marc

repechage

I don't like powdercoat for other reasons such as long term rust protection, although my exposure to it has all been with single stage applications.

The concept that the baking cycle of 400° F will alter the steel is urban legend. Some of this view is from direct experience, some from materials and process education in college.

However, with aluminum I would do some good referencing before I sent one off to be powdercoated.

16Victor

Bingo. And good points. I was speaking from the perspective of the added material bonded to the steel (assumed) tubes. Steel's crystal structure will be unaffected until nearly 800*C.

howeeee

I prefer paint over power coat

Cross Creek

The US and UK navies went to powdercoating everywhere possible a couple of decades ago precisely because their engineers (and real world experience) determined that ships had less corrosion with powdercoat than with traditional paint methods.

Velognome 

Sounds like an opportunity to take the "Dead POS Frame" off his hands for cheap.....remind him it's a dead frame when you ask the price.

repechage

Mil spec powdercoating is not the typical consumer grade materials and or application.

With that in mind, the US Navy does not have structures that resemble a bicycle frame very much. A tubular structure with possibly ornate reinforcements and their sharp edges and the possible multitude of braze ons that have often plenty of sharp edges and small cavities, all surfaces not easy to apply a nice uniform thickness of powder to be melted into a film. Also, consider what this fluid does in its semi molten state, it pulls away from sharp edges reducing the final film thickness there. Physics cannot be avoided. Experienced applicators of powder coat materials can make up for some of this deficit by adding material at problematic regions, a second layer will help even more.
Note I stated my experience was with single stage applications.
What I have found is that upon chemical stripping of all the single stage powder coat jobs on bikes I have had done or purchased over the years there is plenty of corrosion propagating from this thin film areas that was NOT visible from the outside looking in.
On a lugless bike with carefully radiuses edges and few if any braze ons one will have a better outcome.
A two stage application will by definition have a better chance of corrosion protection due to the additional film thickness.
With either approach, powder coat will obscure detail such as serial numbers and engraving, lug windows more, and more often than a wet paint job.

CroMo Mike 

The temper will go out of 6061-T6 Aluminum at something like 275 to 300F. Not a good idea to put an aluminum frame in a 400F oven.

I bet one reason for the increased use of powder coating in manufacturing processes (example: lawn mowers, truck bumpers, car steel wheels, car trailer hitches) is that the manufacturer avoids a lot of environmental regulations associated with use of solvents and thinners. Long-term durability and rust resistance isn't really improved. If you like your powder coated frames, good deal, but, like painted ones, they're not bulletproof.

simmonsgc

Hmmmm, I dunno. Depends on who applies the powdercoat.

etherhuffer 

It seems to me not all powdercoaters and powders are the same. The person above with the Trek photo shows that. His is far better than mine. Like paint, the running of hot liquid coatings is likely variable. Anyone know the base chemical of powdercoat?

pfaustus

I didn't realize that power coating was baked at 400 degrees. That is sufficient to temper hardened steel. That leaves as questions, however, whether the frame is hardened steel or whether it has already been tempered.