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Looking at different builders for my next hardtail. The paint on my last wet paint bike was rather flakey. Not sure if this was just a bad paint job.
What's the differences in the two? Thanks.
 

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As the name implies a powder coat is applied to a part as a dry powder. The part is negatively charged and the powder is positively charged which makes the powder stick. The part is then put in the oven and baked. This allows the paint to "flow" and cure.

Good automotive paint is applied with a spray gun, and will incorporate some kind of hardening agent. It doesn't dry, it cures. A quality automotive paint that is applied well will be almost as durable as a powder coat.
 

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Both types of paint should be quite durable. Think about automotive paint. They are exposed to as much crud as the average bike and still look pretty good after many years and exposure to road grit, oils, salts, etc. It quite possible that you just got a bad paint job with the 'wet' paints. There is all sorts of things that can go wrong. Best thing to do is make sure you go to a reputable place and you'll be fine.

I don't like the appearance of powder coats quite as much as the other type of paint, but I understand powder coating is the toughest paint available.
 

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The main thing to understand is the durability of wet paint or powdercoating is dependant on the surface preparation of the object being painted. If the metal isn't prepped right ANY paint/coating is going to have problems. If there is flaking of the finish I would suspect incorrect application before I'd blame the finish type.
 

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yupp...sounds like a bad paint job. Keep in mind that a lot of paint jobs "stock" on bikes are also "bad". i.e. some steps cut in the process. If you go the automotive paint way make sure that you go with 1. a good quality paint such as DuPont (3000?- it's been awhile since i've looked into the good automotive paint formulations). 2. good prep work.
Look for a place that does the following. Sand blasting of metal to be painted (or just very good stripping). Once the metal is prepped and ready to go we get to the primer stage. You should start with an etching primer. Then a filling primer. Then a base primer (although the filler primer can also be the base primer depending on the formulation). This will be followed by about three to five coats of the base coat, more if needed. So many coats as they are put on thin coats one at a time to "build up" to the final base coat coverage and uniform appearence. On top of the base layer will come the protective coating. Again three to five coats to fully bring out the color and provide protection. (also make sure that the top coats and base coats are compatible i.e. automotive with automotive quality AND formulation.) The final step is to apply a wax/polish.

Keep in mind that there is lot's of sanding between coats etc. This is extremely necessary. Someone who doesn't do the steps either has the industrial equipment to do a proper job, very expensive to buy and thus not a lot have the truly proper tools, or they are skipping steps. Get references and check them out. Price is often a STARTING point for determining decent people. Keep in mind that a high quality automotive paint will be in the $80-$150 range for a quart.

For powder coating, again, make sure that the prep work is there. This determines the overall quality. Although no true "primer" is used this is because of the powder coating process. The main reason why the two are almost similar in durability is because of the hardening agents in powder coating being comparable to properly done priming going the automotive paint route. In powder coating the paint doesn't actually adhere very well to the metal but rather creates a hardened envelope around the frame. With paint it's different as the primer adheres to the metal. The paint adheres to the primer. The two in conjunction with each other gives the durability against flaking off.
 

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powder coating WAY tougher than paint

I've dealt with powder coating and painted products (both as an end user, and product design engineer).

Powder coating is much tougher than paint. One of my suppliers, who does powder coating, must pass certification tests for one of his other customers. This involves powder coating metal plates, then bending them at 90 degree angles, back and forth to see if the coating cracks. I cannot remember how many times the metal is bent, but he showed me some samples that were bent, with no cracking of the powder coating. VERY tough stuff.

Anodizing is a pretty nice finish also. It is pretty tough, but I am not sure how it compares to paint or powder coating.
 

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jabpn said:
This will be followed by about three to five coats of the base coat, more if needed. So many coats as they are put on thin coats one at a time to "build up" to the final base coat coverage and uniform appearence. On top of the base layer will come the protective coating. Again three to five coats to fully bring out the color and provide protection. (also make sure that the top coats and base coats are compatible i.e. automotive with automotive quality AND formulation.) The final step is to apply a wax/polish.

Keep in mind that there is lot's of sanding between coats etc. This is extremely necessary. Someone who doesn't do the steps either has the industrial equipment to do a proper job, very expensive to buy and thus not a lot have the truly proper tools, or they are skipping steps. Get references and check them out. Price is often a STARTING point for determining decent people. Keep in mind that a high quality automotive paint will be in the $80-$150 range for a quart.
Actually with the advent of Urethane paints the automotive painting process has changed quite a bit. Once the primer is sanded smooth a thin layer of the actual color is sprayed on. Once good (but light) color coverage is on, many layers of Urethane clear are added. This is what now gives the paint a deep wet look. If any color sanding or rubbing is done it's to the Urethane clear coat.
 

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Generally speaking powder coating is tougher than paint but it really depends on the quality of the work and preparation. Powder coating is very flexible so it tends to not chip or crack off. The thing with powder coating is its probably not ideal for large flat panel surfaces like cars because you can tell there's some slight rippling from when the powder melts and fuses. This is barely perceptible if at all with a good job on small surfaces such as tubes. If you want that perfect showroom mirror look paint is still the way to go. I had my frame repowder coated by www.spectrumpowderworks.com and they did an absolutely amazing job. Its not cheap but the frame was properly sandblasted and prepped. The finish is undoubtedly the best powder coat job I have ever seen. Its been a year of use since I got it done. After hard use there isn't as much as a scratch or knick on the frame yet. Its that tough.
 

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First, lets get this straight. Powdercoat is not paint, it's plastic. Powdercoat doesn't contain "hardeners", it's not paint. Powdercoat is essentially powdered plastic and is applied as previously described (negatively charged part and positively charged plastic powder) and then baked. Powdercoat is more durable than the best paint job but does have some drawbacks. It is relatively thick and can pose problems when one part has to fit over another (downtube shifters over powdercoated shifter bosses, for example). It can't be applied to all types of materials because not all materials can take the baking process (around 400 degrees, give or take). Regular decals don't work well. They make decals you can put on that will stand up to the baking under a clear powdercoat. You can also put on vinyl decals over the top after coating and baking. You can make powdercoat do just about anything paint can do. As Hecubus said, some can do an amazing job like spectrum powderworks. However, the skill, techniques and equipment needed to do this kind of job is not as available as paint.

That said, even a run of the mill powder shop can do a great job, especially in a single color. Often it is VERY cheap. I've had three frames done by a local shop that does mainly farm machinery, industrial parts and race car frames/parts. Each one cost me $50 and that included all the prep work (taping, bead blasting, coating, baking). They turned out great. Look great, very durable.
 

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One thing I would like to add to Meloh1's post is that many paints these days are actually plastics too. Urethane paints, for example, are simply a sprayable sort of polyurethane plastic. I once mistakenly added too much catalyst to a batch of urethane I was spraying and had it harden in the paint gun. The result was a paint gun full of hard plastic... not very fun to clean out!
 

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Lumbee1 said:
Does anyone have pictures of each? I am very interested in building a SS project bike and would like the frame powdercoated.
Pictures? We don' need no steenking pictures. You see these things every day. That white lawn furniture with the indestructible white finish, that's powder coat. Every car you see is one or another version of paint. If you need a picture go to carswell coatings (sorry, don't have a URL handy, it'll google right up) and check out their gallery of customer pieces in anodize and powder coat.

Ron
 

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actually

meloh1 said:
First, lets get this straight. Powdercoat is not paint, it's plastic. Powdercoat doesn't contain "hardeners", it's not paint. Powdercoat is essentially powdered plastic and is applied as previously described (negatively charged part and positively charged plastic powder) and then baked. Powdercoat is more durable than the best paint job but does have some drawbacks. It is relatively thick and can pose problems when one part has to fit over another (downtube shifters over powdercoated shifter bosses, for example). It can't be applied to all types of materials because not all materials can take the baking process (around 400 degrees, give or take). Regular decals don't work well. They make decals you can put on that will stand up to the baking under a clear powdercoat. You can also put on vinyl decals over the top after coating and baking. You can make powdercoat do just about anything paint can do. As Hecubus said, some can do an amazing job like spectrum powderworks. However, the skill, techniques and equipment needed to do this kind of job is not as available as paint.

That said, even a run of the mill powder shop can do a great job, especially in a single color. Often it is VERY cheap. I've had three frames done by a local shop that does mainly farm machinery, industrial parts and race car frames/parts. Each one cost me $50 and that included all the prep work (taping, bead blasting, coating, baking). They turned out great. Look great, very durable.
Actually paint is a resin. Or rather a type of resin and hardeners are often added in the making of the resin powder used in powder coating. Here's a good link from SME that gives an overview comparing paint to powder coating. The "new" automotive paints are Acrylic Eurethane Enamels and they can be, if done right and in the right formulations, as strong and crack resistant as powder coating. Keep in mind that the "new" automotive paints were first used in the aviation industry.

http://www.sme.org/gmn/video/pdf/VT00PUB1.pdf#search='hardening%20agents%20in%20powder%20coating'
 

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What material frame is it going on? Powder coating is more durable, but good paint is better at preventing rust. If it is a steel frame that will be riden on the salty roads, I would go with paint.

Another thing that will greatly increase the corrosion resistance of steel is if they do a phosphate dip before painting or powder coating. A good paint or powder coating place should be able to do this.
 
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