Powder Coating

[cycl...@gmail.com]

The colors and consistencies you can get in powder coating is fantastic. I found some slightly metallic very bright blue.

The problem is that powder coaters are not bicycle painters so the rear dropouts that are chromed will be covered as well as everything else.

So does anyone have an idea of how to remove the powder coating from the dropouts without destroying the chrome at the same time?

[Joerg]

AFAIK it's done the traditional way:

https://itstillruns.com/remove-paint-chrome-4809619.html

For next time: Powder coat places are very much used to masking areas
but they have to be told which ones. With ultrasound machine chassis we
had them do that all the time because some panels had to make electrical
contact for safety, EMC, noise and other reasons.

--
Regards, Joerg

http://www.analogconsultants.com/

[cycl...@gmail.com]

That did give me the idea that I can't use my miniature wire brush on the rotary tool. I don't know if lacquer thinner could work on powder coat but I can certainly try.

I powder coated my wife's Mercian, spray painted on the contrasting headtube color and then put on the decals. That bike road coast to coast and there is only one small nick in the powder coat from laying it in the station wagon on top of a wheel. Otherwise after 20 years it looks almost new.

[Ian Field]

"Joerg" <ne...@analogconsultants.com> wrote in message
news:evj2b0...@mid.individual.net...

> On 2017-08-16 06:53, cycl...@gmail.com wrote:
>> The colors and consistencies you can get in powder coating is
>> fantastic. I found some slightly metallic very bright blue.
>>
>> The problem is that powder coaters are not bicycle painters so the
>> rear dropouts that are chromed will be covered as well as everything
>> else.
>>
>> So does anyone have an idea of how to remove the powder coating from
>> the dropouts without destroying the chrome at the same time?
>>
>
> AFAIK it's done the traditional way:
>
> https://itstillruns.com/remove-paint-chrome-4809619.html

Paint is totally different to powder coat, AFAIK: traditional masking will
tend to rip off a strip of coating where you want it to stay.

Powder coating is most often done electrostatically - I vaguely remember
something about painting melted wax onto the chrome bits. The right kind of
wax is an insulator that doesn't electrostatically hold the sprayed on
powder - or not so much anyway.

The end result still needs a bit of finishing round the edges - but you
shouldn't end up having to strip it back and start over.

[Sir Ridesalot]

Get whomever does the powder coating to mask off the chromed areas you don't want the powder coat to go onto.

Cheers

[John B.]

I read that "Dichloromethane (Methylene chloride... ie Klean-Strip
Aircraft stripper or Permatex Gasket Remover)" will remove powder
coating" and my own experience has been that MEK (methyl ethyl ketone)
will soften it. There are also a number of commercial products
designed to remove powder coating.
--
Cheers,

John B.

[John B.]

I usually have bike frames powder coated in two or more colors and the
people that do it here are quite adept at masking. Whether to cover
chrome plating or just where two colors join. I'm told that they use a
"special masking tape" that will withstand the oven temperature.
--
Cheers,

John B.

[Joerg]

It's being done:

http://www.powdercoatguide.com/2013/08/masking.html

The edge line won't always be as sharp as with paint but on the near the
inside of the rear dropouts I guess it won't even be a cosmetic issue.

[Joerg]

On 2017-08-16 09:20, cycl...@gmail.com wrote:
> On Wednesday, August 16, 2017 at 7:15:01 AM UTC-7, Joerg wrote:
>> On 2017-08-16 06:53, cycl...@gmail.com wrote:
>>> The colors and consistencies you can get in powder coating is
>>> fantastic. I found some slightly metallic very bright blue.
>>>
>>> The problem is that powder coaters are not bicycle painters so
>>> the rear dropouts that are chromed will be covered as well as
>>> everything else.
>>>
>>> So does anyone have an idea of how to remove the powder coating
>>> from the dropouts without destroying the chrome at the same
>>> time?
>>>
>>
>> AFAIK it's done the traditional way:
>>
>> https://itstillruns.com/remove-paint-chrome-4809619.html
>>
>> For next time: Powder coat places are very much used to masking
>> areas but they have to be told which ones. With ultrasound machine
>> chassis we had them do that all the time because some panels had to
>> make electrical contact for safety, EMC, noise and other reasons.
>
> That did give me the idea that I can't use my miniature wire brush on
> the rotary tool.

Try not to ever do that on a bicycle.


> ... I don't know if lacquer thinner could work on powder

> coat but I can certainly try.
>

Can't hurt to talk to a shop in your area that does powder coating. They
might be able to sell you a solvent or, if that comes in a bottle with
skull and bones on it, they might offer to do the job inhouse for a
reasonable fee.

> I powder coated my wife's Mercian, spray painted on the contrasting
> headtube color and then put on the decals. That bike road coast to
> coast and there is only one small nick in the powder coat from laying
> it in the station wagon on top of a wheel. Otherwise after 20 years
> it looks almost new.
>

You should see my bikes. All scratched up and quite dirty. With the MTB
that is inevitable due to the frequent rock hits.

http://analogconsultants.com/ng/bike/Muddy3.JPG

The rear looks very different now, with a diagonal strut and a smaller
electronics box. But it's just as dirty.

[Ian Field]

"John B." <sloc...@gmail.com> wrote in message
news:viq9pct0kcm36rs9r...@4ax.com...

Probably OK if you apply it thin enough, but that stuff has tensile
strength.

[jbeattie]

I wasn't going to say anything for fear of sounding like a weight-weenie, but powder paint is heavy. I had a frame painted, and the job was partly botched, so they put on a second coat. Crap man, two coats probably added a pound to the frame.

-- Jay Beattie.

[John B.]

On Thu, 17 Aug 2017 18:50:43 +0100, "Ian Field"

I'm not sure what you mean here. "Tensile strength"?

What I specify, and what "my shop" does is to apply the lighter color
and bake, mask and apply the darker color and bake, apply a clear
coat, and bake. If you carefully rub your finger over the "joint"
between the two colors you cannot feel any difference. It is smooth.

I might add, that I make it a point to talk to people, get a little
friendly, ask about their kids, complement the ladies on their hair
style, etc. I even give the guys doing the actual work a "bit for
beer" and I always seem to get satisfactory service.
--
Cheers,

John B.

[John B.]

I thought the same and weighed a frame before and after with an
electronic scale that weighs to 0.001 Kg. (about 0.04 Ounce) and there
was no difference in the scale reading :-)

--
Cheers,

John B.

[cycl...@gmail.com]

This is good information since I was worried about the rear wheel adjusters. The frame had a worn out bottom bracket so I left it installed to protect the threads.

The only thing I was concerned about was perhaps masking off the chrome rear dropouts but decided that it wouldn't matter because the powder coat is just as nice looking as the chrome would be.

[cycl...@gmail.com]

The shop had to sandblast the old paint off so I imagine that messed up the chrome surface anyway.

[Ian Field]

"John B." <sloc...@gmail.com> wrote in message

news:tgfcpcd77q8gm4sf8...@4ax.com...

You have to cut round what you want to peel off or it peels off a lot more
than you want.

[Ian Field]

<cycl...@gmail.com> wrote in message
news:f5a92870-1571-4df0...@googlegroups.com...

The powder coat will crush when you tighten up - soon looks scruffy.

[Joerg]

Yes, that may already have compromised the chrome plating. Hopefully not
to badly.

[cycl...@gmail.com]

I just called and I don't think they received the custom color yet and so haven't started. I asked them to mask off the dropouts.

[Ian Field]

"Joerg" <ne...@analogconsultants.com> wrote in message

news:evoufo...@mid.individual.net...

there's also various kinds of shot peening, sometimes with plastic beads.
there may be a formulation that shifts paint without damaging chrome.

[Joerg]

If they do not remove it right after coating it will become thoroughly
caked in place. You could possibly still pry it loose but then some of
the new powder coat will chip off. They should be able to pretect
threads without the BB being installed. Also, on the drive side you'd
want a clean non-coated face or the newly mounted BB may not seat itself
properly.

>> The only thing I was concerned about was perhaps masking off the
>> chrome rear dropouts but decided that it wouldn't matter because the
>> powder coat is just as nice looking as the chrome would be.
>
> The powder coat will crush when you tighten up - soon looks scruffy.

That, and it has too much give, making for a mushy axle mount. I would
not want powder coat on that surface. Even less for the BB. I'd really
have them mask such areas.

[sloc...@gmail.com]

On Fri, 18 Aug 2017 19:08:03 +0100, "Ian Field"

Probably the reason I don't have any problem is that "my shop" gives
me the frame ready to install the parts. No tape at all :-)

[retrog...@gmail.com]

I know I'm repeating myself, but nobody else can mask your frame for painting as well as you can do it yourself, because you can take the time. I sure do like masking it myself and painting it with single-stage automotive paint. It's easy to buff out and re-spray if it gets scratched. In my humblest of opines, I think powder coat may be overkill.

[sloc...@gmail.com]

On Sat, 19 Aug 2017 07:22:49 -0700 (PDT), retrog...@gmail.com
wrote:

>I know I'm repeating myself, but nobody else can mask your frame for painting as well as you can do it yourself, because you can take the time. I sure do like masking it myself and painting it with single-stage automotive paint. It's easy to buff out and re-spray if it gets scratched. In my humblest of opines, I think powder coat may be overkill.

Perhaps it is. On the other hand I can take a rusty, old, oily, frame
with a number of newly brazed on bits and leave it with "my powder
coater" , pick it up in about a week, and it looks pretty fine... cost
is about $15 or $20.

I did, some time ago, check with a bloke who paints boats using two
part paint and while he had never painted a bike and wouldn't quote a
firm price mentioned "the neighborhood of $50, or maybe more".

(which to be honest is why I prefer powder coating :-)

As for do it yourself it is costly for only a few frames as you will
need a proper spray gun and a source of compressed air, a paint booth,
or some way to be certain that you can paint in a dust free area, and
in my experience proper two part paint is seldom sold in small lots.
International Perfection is running about $100 a quart. Plus the
thinner is probably $15 - $20 a quart.

[cycl...@gmail.com]

I don't know where you live but it must be out in the wilds of Nebraska. A powder coating job on a frame here normally cost about $150 and the one I'm getting uses some special powder coat that is only available from a company that the local coater doesn't normally do business with so they have to pay full retail for the powder and all the paperwork that involves so it will be $210.

If I get a color they normally use it is normally a day or two but it's been over a week and they haven't even started meaning the powder hasn't shown up.

[John B.]

My powder coating guy is in Phuket, Thailand, which is a tourist
resort and thus living costs more expensive then the usually Thai
small town.

As for price, I have had a number of frames done there in the past
year or so and I get charged the same whether it is one color, two
color, or two color plus clear coat. Assuming that it is a color that
they have in stock. From discussions with them they set prices
according to the area that is powder coated and a bicycle frame
doesn't have too many square inches.

Salaries are lower here due to a lower cost of living and you have to
pay the help whether they are smoking cigarettes or masking bike
frames and because Thailand has universal medical care there is no add
ons for Medicare, etc., so labour costs are essentially what you hand
the guy on payday. It probably makes a difference.

>If I get a color they normally use it is normally a day or two but it's been over a week and they haven't even started meaning the powder hasn't shown up.

I can't even begin to guess what the charge would be if I asked for a
special color, but I'd guess it would be high considering the trouble
of ordering something special, CIF to Thailand, along with the fact
that probably nobody will ever want that color again, etc. :-)

--
Cheers,

John B.