painting small steel frame damages

The entry/joint area may have a paint resisting surface or/and primed incorrectly

I use soft paint. No chips, scrapes off

On Fri, 5 May 2017 19:37:54 -0700 (PDT),
wrote:

That's pretty funny - we have an entire string of having to touch up scratches on bicycle paint and you ask "how hard a paint do you really need on a bike".

Apologies if I'm hijacking the thread, Gene, but I don't think that paint hardness and scratch/chip resistance are the same thing. For example, early Dupont Imron paint was very hard but chipped easily.

If anybody knows more about paint than I do, feel free to correct me.
The imron, properly applied was tougher than nails. CAMF Acrylic on
the other hand was hard as glass and chipped as badly. We had imron
clear over the camf acrylic on the '57 Fargo and stone chips were not
a problem. My older brother had several coats of imron clear over gold
metalflake on the "goldenrod" Cricket. By the time he sold the car
much of the front fenders were virtually plastic, with the metal
rusted right out from behind. That stuff was TOUGH!!!!
Perhaps if the hardener was mixed too strong or something it would get
too hard - I don't know. My little brother painted both vehicles, and
he painted a LOT of Imron - much of it on over-the-road trucks - much
of it on sulpheric acid tankers. Can't ask him about details as he
left this earth on his own terms a few years back - - -

On Fri, 5 May 2017 19:31:10 -0700 (PDT), wrote:

On Friday, May 5, 2017 at 6:44:59 PM UTC-7, John B Slocomb wrote:
On Fri, 5 May 2017 07:42:41 -0700 (PDT), wrote:

On Thursday, May 4, 2017 at 5:52:15 PM UTC-7, wrote:
Emmanuel, I'm afraid I am not big on repairing chips in a frame's paint. When the bike gets too chipped and has too many rust spots to suit me, I strip the components off the frame, sandblast it and paint it with single-stage automotive paint. Although 2-stage (clear coat) jobs are popular these days, I think clear coat would look obviously inauthentic. IMHO, single stage paint more closely duplicates the original finish.

You need a fairly good-sized air compressor to run a sandblaster. I use a Campbell Hausfeld 2-stage model that delivers about 18 SCFM and has an 80-gallon air tank. Just about any portable, pressure-fed sandblaster will do the job. Avoid siphon-fed blasters.

Almost any city has locations that will sandblast and powdercoat a frame and fork. This procedure is dirt cheap and the finish extremely long lasting if not the height of glossy finishes.

The shop I use does a two coat powder coating with "clear coat" as the
second layer. It does produce a fairly shiny coating although not as
glossy as "22 coats of hand rubbed lacquer".

I live one mile away from CycleArt. I dropped in and asked what he wanted for a paint job and he said $1200 with decals and a minimum of two months lead. The powder coat complete was $50 the next day.

For a frame and fork I pay about $57 at current exchange rates for
powder coating.

On Fri, 5 May 2017 22:40:05 -0400, Frank Krygowski
wrote:

On 5/5/2017 10:31 PM, wrote:
On Friday, May 5, 2017 at 6:44:59 PM UTC-7, John B Slocomb wrote:
On Fri, 5 May 2017 07:42:41 -0700 (PDT), wrote:

On Thursday, May 4, 2017 at 5:52:15 PM UTC-7, wrote:
Emmanuel, I'm afraid I am not big on repairing chips in a frame's paint. When the bike gets too chipped and has too many rust spots to suit me, I strip the components off the frame, sandblast it and paint it with single-stage automotive paint. Although 2-stage (clear coat) jobs are popular these days, I think clear coat would look obviously inauthentic. IMHO, single stage paint more closely duplicates the original finish.

You need a fairly good-sized air compressor to run a sandblaster. I use a Campbell Hausfeld 2-stage model that delivers about 18 SCFM and has an 80-gallon air tank. Just about any portable, pressure-fed sandblaster will do the job. Avoid siphon-fed blasters.

Almost any city has locations that will sandblast and powdercoat a frame and fork. This procedure is dirt cheap and the finish extremely long lasting if not the height of glossy finishes.

The shop I use does a two coat powder coating with "clear coat" as the
second layer. It does produce a fairly shiny coating although not as
glossy as "22 coats of hand rubbed lacquer".

I live one mile away from CycleArt. I dropped in and asked what he wanted for a paint job and he said $1200 with decals and a minimum of two months lead. The powder coat complete was $50 the next day.

That's pretty interesting. About ten years ago, I welded up some nice
ornamental railings for our indoor stairs and outdoor balcony. I looked
into powder coating, and while I don't remember the price, I decided it
was exorbitant. It was much, much higher than $50!


I just built a wheel truing stand. Powder coating it cost me 400 baht
or $11 at currant exchange rates. I asked about powder coating the
entire rear bumper for my pickup and was told, maybe 3000 baht (about
$85 dollars). The bumper is about 5 square feet in area and they
mentioned that they would have to do both sides, so ~10 square feet of
coverage.

I think that the materials are pretty cheap and charges are perhaps
more influenced by how long the job is going to take and how much
space will it take up in the oven, thus limiting how many pieces
can be crammed in. At least back when the shop started powder coating
the owner mentioned how much it cost to run one load through the oven.

On Fri, 05 May 2017 23:18:48 -0400, wrote:

On Fri, 5 May 2017 12:27:11 -0700 (PDT), wrote:

On Friday, May 5, 2017 at 11:49:28 AM UTC-7, wrote:
I can't really argue with you, Gene, except for the problem of masking after the sandblasting. It seems that inevitably the powder coat guy doesn't mask something that should have been masked (and then you have to remove the overspray; can be very tedious) or he masks something that shouldn't have been masked, and then it looks like hell. I like to do my own masking job.

Overall, I haven't found powder coat to be that much more durable than single-stage urethane enamel. They each have their strong points. Yes, powder coat has a lot more surface hardness, but how hard a paint do you really need on a bike? Whereas urethane is more flexible and therefore doesn't tend to crack as much. A fortiori because I'm spraying the low-VOC California product and find it to be a very good paint giving excellent results.

That's pretty funny - we have an entire string of having to touch up scratches on bicycle paint and you ask "how hard a paint do you really need on a bike".

And the point where by Colnago B-stay enters the frame carrier the urethane paint cracked all around it because of the movement between the B-stand and the frame and you say "urethane is more flexible and therefore doesn't tend to crack as much".

Obviously our experiences are exactly opposite.
Paint thatb is too "hard" cracks and chips. What you need is paint
that is "tough". "tough" and "hard" are not the same, and although not
mutually exclusive, are not GENERALLY found in the same paint.

The two-part polyurethane paints, like the Imron mentioned are both
hard, i.e., resist scratching and tough, i.e., don't crack. They are,
however, expensive and can be difficult to apply.

On 5/5/2017 9:16 PM, wrote:
add a small amount z to a small test volume of x ... 'measure' both volumes

when close try a volume for a small out of sight chip paint let dry

Both dry and larger volumes will skew the results

visit the paint Store fir a demo


And keep your units in mind:
http://money.cnn.com/2017/05/04/news...ada/index.html

Proof is not percent

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 5/5/2017 9:31 PM, wrote:
On Friday, May 5, 2017 at 6:44:59 PM UTC-7, John B Slocomb wrote:
On Fri, 5 May 2017 07:42:41 -0700 (PDT), wrote:

On Thursday, May 4, 2017 at 5:52:15 PM UTC-7, wrote:
Emmanuel, I'm afraid I am not big on repairing chips in a frame's paint. When the bike gets too chipped and has too many rust spots to suit me, I strip the components off the frame, sandblast it and paint it with single-stage automotive paint. Although 2-stage (clear coat) jobs are popular these days, I think clear coat would look obviously inauthentic. IMHO, single stage paint more closely duplicates the original finish.

You need a fairly good-sized air compressor to run a sandblaster. I use a Campbell Hausfeld 2-stage model that delivers about 18 SCFM and has an 80-gallon air tank. Just about any portable, pressure-fed sandblaster will do the job. Avoid siphon-fed blasters.

Almost any city has locations that will sandblast and powdercoat a frame and fork. This procedure is dirt cheap and the finish extremely long lasting if not the height of glossy finishes.

The shop I use does a two coat powder coating with "clear coat" as the
second layer. It does produce a fairly shiny coating although not as
glossy as "22 coats of hand rubbed lacquer".

I live one mile away from CycleArt. I dropped in and asked what he wanted for a paint job and he said $1200 with decals and a minimum of two months lead. The powder coat complete was $50 the next day.


Not only apples and oranges (IMHO Jim's the absolute best
painter in our industry, period.) but you are no longer in
the neighborhood, California having claimed one more scalp
in their endless war against business. Cyclart is in Little
Rock now.



--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 5/5/2017 9:37 PM, wrote:
That's pretty funny - we have an entire string of having to touch up scratches on bicycle paint and you ask "how hard a paint do you really need on a bike".

Apologies if I'm hijacking the thread, Gene, but I don't think that paint hardness and scratch/chip resistance are the same thing. For example, early Dupont Imron paint was very hard but chipped easily.

If anybody knows more about paint than I do, feel free to correct me.


Imron was relatively soft (doesn't buff well) and was
relatively chip-resistant compared to the brittle lacquers
of that era. It may, like powder, suffer from corrosion
veins spreading out under a chip.

(not to say every Imron application was mixed correctly or
that every substrate was prepped well or that Imron won't
ever chip)

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

Cyclart is in Little Rock ...internet is in LR ! Faubus or not...

when in Wests, if there's time I visit paint...visit.

https://www.google.com/#q=west+marin...e+paint&spf=75

one consideration, if you paint the 57 primer gray with a patch of red rusto here there there's less chance of theft

On Saturday, May 6, 2017 at 9:08:26 AM UTC-4, wrote:
Cyclart is in Little Rock ...internet is in LR ! Faubus or not...

when in Wests, if there's time I visit paint...visit.

https://www.google.com/#q=west+marin...e+paint&spf=75

one consideration, if you paint the 57 primer gray with a patch of red rusto here there there's less chance of theft

my brief ride out back the Buffalo R. found a delightful rolling open sunny countryside ....inflicted with chip seal.