Maybe I should use single stage
- Thread starter sandybob
- Start date
As of 10 years ago, over 75% were using waterborne. I have no answer as to if it is having an effect on adhesion. Haven't really heard of an issue with the base not sticking to primer with it, but certainly could be a factor.
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dhutton01
Backyard Hack
I was told by a waterborne user that the base is tough to sand, it just tears which sounds to me like the adhesion is poor. This was in reference to doing repairs to the base before applying clear. He hated the waterborne base.
Don
crashtech
Combo Man & Mod
Having toured an OE factory and with their processes in mind, it would seem that adhesion loss between stages would be due to a mismatch between dry times and next stage times. Like they accidentally overbake a stage is what I'm trying to say. Underbaking might cause shrinkage later, but won't have adhesion loss. OEMs are in a constant state of experimentation to provide finishes that look good and can be warrantied but don't cost too much and don't incur EPA fines.
Yes
B
BenKlesc
Any questions. Feel free to ask...
B
BenKlesc
Anyways hello folks. Been a member on this forum for a few years now and just happen to be scrolling on past and saw this thread. First of all this is one of the most fascinating topics I find about painting. Let me add a few points.
Urethane paints are superior to lacquer paints in every way. I have only ever painted with urethane products and never hope to touch lacquer. Lacquer and enamels are much weaker finishes and do not hold up to the elements in terms of fading like the modern paints do.
What I meant was that base coat is no different from lacquer in that it's not a catalyst structure. It air drys and even if you use the optional hardener. There is no base coat on the market that must be baked in order to be used. Therefore there is no UV protection. Overtime as you buff clear coat you are thinning and removing your UV protection in the orange peel. Overtime this will fail. Scratches will also cloud your clear coat unlike on a single stage product where scratches are more easily removed. Much easier to buff and work with, and make spot repairs. You also cannot use siphon feed guns on clear coat because your HVLP produces the orange peel as an asset and not defect.
I would not recommend not using clear coat, but if you plan on keeping around a project car for more than a few years there are many who have looked into clearing over single stage instead of using base which would in fact be a way more durable finish. However once the clear begins to thin in random spots, you have to add a new layer of clear coat because single stage will never stay as glossy as clear. Luckily though you can blend new coats into previous coats, unlike if you were working with base coast. That in theory shows that it could hold up much longer through superior UV protections and catalyst structure that prevent it from failing over time. I wouldn't mind owning a car with just single stage.
On my two project cars and one in my profile pic, I will be solely using single stage because I believe it can be a superior product. One of my projects has already been painted in base/clear and I will be taking it back down to bare metal and switching to single stage. A single stage job will simply hold up far longer than bc/cc ever will because of the nature of a catalyst single chemical structure. To make that clear that does not mean it will not fade, and in fact single stage can fade very rapidly in sun and requires more maintenance to keep a high gloss finish. That is a separate topic all together though. In the nature of current products, if you go with single stage it will be impossible to fail. If you look into the history of base, it was brought into the industry to save production shops time and money as well as factories. It's not always a superior product. Especially if it's a show car where you are always cutting and buffing clear. The fastest way to lead to paint failure. By the way in many cases modern paint systems in my view are superior depending on the results you are looking for. Definitely superior to the average car owner that daily commutes.
Urethane paints are superior to lacquer paints in every way. I have only ever painted with urethane products and never hope to touch lacquer. Lacquer and enamels are much weaker finishes and do not hold up to the elements in terms of fading like the modern paints do.
What I meant was that base coat is no different from lacquer in that it's not a catalyst structure. It air drys and even if you use the optional hardener. There is no base coat on the market that must be baked in order to be used. Therefore there is no UV protection. Overtime as you buff clear coat you are thinning and removing your UV protection in the orange peel. Overtime this will fail. Scratches will also cloud your clear coat unlike on a single stage product where scratches are more easily removed. Much easier to buff and work with, and make spot repairs. You also cannot use siphon feed guns on clear coat because your HVLP produces the orange peel as an asset and not defect.
I would not recommend not using clear coat, but if you plan on keeping around a project car for more than a few years there are many who have looked into clearing over single stage instead of using base which would in fact be a way more durable finish. However once the clear begins to thin in random spots, you have to add a new layer of clear coat because single stage will never stay as glossy as clear. Luckily though you can blend new coats into previous coats, unlike if you were working with base coast. That in theory shows that it could hold up much longer through superior UV protections and catalyst structure that prevent it from failing over time. I wouldn't mind owning a car with just single stage.
On my two project cars and one in my profile pic, I will be solely using single stage because I believe it can be a superior product. One of my projects has already been painted in base/clear and I will be taking it back down to bare metal and switching to single stage. A single stage job will simply hold up far longer than bc/cc ever will because of the nature of a catalyst single chemical structure. To make that clear that does not mean it will not fade, and in fact single stage can fade very rapidly in sun and requires more maintenance to keep a high gloss finish. That is a separate topic all together though. In the nature of current products, if you go with single stage it will be impossible to fail. If you look into the history of base, it was brought into the industry to save production shops time and money as well as factories. It's not always a superior product. Especially if it's a show car where you are always cutting and buffing clear. The fastest way to lead to paint failure. By the way in many cases modern paint systems in my view are superior depending on the results you are looking for. Definitely superior to the average car owner that daily commutes.
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wrong
Only products that must be baked have UV protection?
Easier to buff and work with depends on the particular product chosen. Grouping all single stage and all BC/CC systems together is not practical. There are good products and junk in both systems. Not all gravity feed guns are HVLP, and are not designed to produce orange peel, only increase transfer efficiency and reduce overspray.
Chris_Hamilton
Trying to be the best me, I can be
@BenKlesc
First I'm not arguing BC/CC over Single Stage or that one is superior to the other. They both have their place and advantages and disadvantages.
Do you realize that Single Stage Urethane and (Poly) Urethane clears are very closely related? So essentially what is true for one is true for the other. Any clear will fail if too little is applied (millage) and then buffed. Any Single Stage will fail if too little millage is applied. They might fail in different ways, clear delaminates off of the base, single stage mainly oxidizes to the point where you cant bring back the gloss. But they do fail. Single stage urethanes have actually less UV protection than a Base clear because the pigment/toners in the SS are right there on the surface. Basecoats are protected under a layer of clear.
You have to apply more clear than you need if you are cutting and buffing. (Just as you would have to apply more SS than you need if you cut and buff) Done correctly it will last for decades (assuming you are using quality products). Once a clear is cut and buffed unless it's abused there is no need for any further cutting nor any heavy buffing. Any maintenance type buffing done after the initial cut and buff, will only remove a negligible amount of material and is not an issue provided enough clear was applied initially. Where it is an issue is when not enough clear was applied and then an excessive amount of cutting and buffing was done. The same would hold true for a Single stage.
Single Stage Urethanes that are blended within a panel are much harder to repair than a BC/CC. And once repaired they are flawed, in that the edges of the repair are very thin and will eventually fail. There is no getting around that if you do a within the panel blend on single stage. BC/CC are much easier to repair and and because the blend panel is fully cleared will last as long as the rest of the job. No one blends Single Stage unless they have absolutely no choice. Just like no Pro will blend clear within a panel on anything but a the lowest level type repairs. The edge will eventually fail.
Another aspect of blending a Single Stage versus a Base/Clear and probably the most important is blending the actual color and getting the blend area perfect. It is much, much, harder to do with a SS versus a Base/Clear. Especially if the color is slightly different than what is on the car. Very rare that you wil ever get a color that is the exact match to what is on the car, (OEM or Refinish) that is why being able to blend and blend-ability is so important. With a Base/clear system that type of blending is done every day and can be done so that it is impossible to discern the blend. That is not the case with a Single Stage Urethane. It's not even close. Blend-ability and ease of repair is probably the main reasons Base/Clears are so popular. At least among Collision Repair Shops. That is also why base/clears are popular among Restoration and Custom paint guys. Ease of spraying, and the ability to repair.
Solid color Single Stage Urethanes look great. That is the one area where they are superior to a base/clear. Deeper richer look that more closely resembles Lacquers from the past.
Single Stage Urethane the DOI (distinctness of image) of a metallic is inferior to the DOI of a Base/Clear. Not to mention that it is not easy to shoot a SS urethane metallic. It can absolutely be one of the most difficult things to shoot. Especially a SS silver or grey metallic.
A quality HVLP will spray any clear or SS as slick or as full of peel as the skill of the person doing the spraying.
I would hesitate speaking in absolutes, until you have the practical experience and knowledge to do so.
First I'm not arguing BC/CC over Single Stage or that one is superior to the other. They both have their place and advantages and disadvantages.
Do you realize that Single Stage Urethane and (Poly) Urethane clears are very closely related? So essentially what is true for one is true for the other. Any clear will fail if too little is applied (millage) and then buffed. Any Single Stage will fail if too little millage is applied. They might fail in different ways, clear delaminates off of the base, single stage mainly oxidizes to the point where you cant bring back the gloss. But they do fail. Single stage urethanes have actually less UV protection than a Base clear because the pigment/toners in the SS are right there on the surface. Basecoats are protected under a layer of clear.
You have to apply more clear than you need if you are cutting and buffing. (Just as you would have to apply more SS than you need if you cut and buff) Done correctly it will last for decades (assuming you are using quality products). Once a clear is cut and buffed unless it's abused there is no need for any further cutting nor any heavy buffing. Any maintenance type buffing done after the initial cut and buff, will only remove a negligible amount of material and is not an issue provided enough clear was applied initially. Where it is an issue is when not enough clear was applied and then an excessive amount of cutting and buffing was done. The same would hold true for a Single stage.
Single Stage Urethanes that are blended within a panel are much harder to repair than a BC/CC. And once repaired they are flawed, in that the edges of the repair are very thin and will eventually fail. There is no getting around that if you do a within the panel blend on single stage. BC/CC are much easier to repair and and because the blend panel is fully cleared will last as long as the rest of the job. No one blends Single Stage unless they have absolutely no choice. Just like no Pro will blend clear within a panel on anything but a the lowest level type repairs. The edge will eventually fail.
Another aspect of blending a Single Stage versus a Base/Clear and probably the most important is blending the actual color and getting the blend area perfect. It is much, much, harder to do with a SS versus a Base/Clear. Especially if the color is slightly different than what is on the car. Very rare that you wil ever get a color that is the exact match to what is on the car, (OEM or Refinish) that is why being able to blend and blend-ability is so important. With a Base/clear system that type of blending is done every day and can be done so that it is impossible to discern the blend. That is not the case with a Single Stage Urethane. It's not even close. Blend-ability and ease of repair is probably the main reasons Base/Clears are so popular. At least among Collision Repair Shops. That is also why base/clears are popular among Restoration and Custom paint guys. Ease of spraying, and the ability to repair.
Solid color Single Stage Urethanes look great. That is the one area where they are superior to a base/clear. Deeper richer look that more closely resembles Lacquers from the past.
Single Stage Urethane the DOI (distinctness of image) of a metallic is inferior to the DOI of a Base/Clear. Not to mention that it is not easy to shoot a SS urethane metallic. It can absolutely be one of the most difficult things to shoot. Especially a SS silver or grey metallic.
I have no idea what you are talking about here. Explain please. A quality Siphon feed gun will spray clear fine. It will simply use much more material and put out much more overspray. Those two things are the main reasons siphons are no longer used.
A quality HVLP will spray any clear or SS as slick or as full of peel as the skill of the person doing the spraying.
I would hesitate speaking in absolutes, until you have the practical experience and knowledge to do so.
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B
BenKlesc
That's true! I've heard that before, and that is why clear coat over single stage won't delaminate in the same way. I've always believed clear coat is essentially single stage urethane with no pigment. It drys in the same way single stage products do. In essence, clear coat is essentially no different from single stage.
That's very true as well that you say. In fact I would say, most drivers on the road have no use for single stage. It depends on your definition of longevity. Most drivers on the road would rather have a low maintenance and durable finish that doesn't fade. Most drivers on the road are not constantly buffing. My big issue is this.
I have found that clear coat is more prone to scratching. The only way to get scratches out of clear is by wet sanding. Buffing only goes so far. Again for most these scratches are unnoticeable, but for a show car where you want a pristine finish then it will annoy you to the hilt. I have found it much easier to use car covers over single stage finishes. As soon as I put a cover over clear coat I notice scratches immediately no matter how soft it is. I have found that single stage finishes are more durable, in that they are less prone to scratching. That is why they say that single stage urethanes and lacquer have greater depth. Clear dulls overtime, and so does single stage as it fades. The difference being that it's easier to buff single stage than clear. With clear you can only go so far. Also of course if you store a show car in the garage it will take a lot longer to fade, and especially the urethane single stage products they have out now. I think I'm in agreement with everything you say.
So again I will say, I believe it depends on the definition of repair. To clarify, I believe the process of painting single stage and clear are in essence no different. When I was talking about making blends in the repair I was more explaining that it's easier to make repairs on lacquer. I believe a proper repair would be repainting the entire panel no matter what. A spot repair will only take you so far. On a show car I would never feel comfortable making spot repairs.
Now, the difference with single stage urethane and bc/cc would be this. Any repair involves going back to primer, applying new base, and clear. With single stage you can just paint over a new coat. You cannot really sand or work with base, as easily as you can sand single stage. Now for all practical purposes, not including metallics which is a whole separate debate. Personally I would rather work with restoring single stage every time. You could take a 50 year old paint job, sand it with 400 grit and add on a new coat. The scratches will fill in. The chemical structure of single stage will never fail in that sense like clear delaminates from base. Once clear begins delaminating you are taking it back to primer. I believe single stage can outlast in that regard.
So I have been in discussion with a lot of old timers, and I asked them if there was anything they liked about siphon feed guns. They told me that the nature of HVLP guns introduces more orange peel. Like you said above, it's actually more difficult to paint single stage and get a good finish. Perhaps it takes a lot more skill in many instances, because what's coming out of your gun will be your final finish. There is no clear.
I've been told by a few folks that with single stage, you will get a lot less orange peel with a siphon. I'm not sure why that is but I'm sure there is a reason if I look into it. Probably related to air pressure. Now with bc/cc, increased orange peel actually works to the advantage of modern paints, because the more orange peel you have the more UV protection your finish will obtain. When you buff and wet sand orange peel away on clear which most classic restoration shops do, you are reducing the life expectancy of your show car. That is why sanding the factory finish voids the warranty. With single stage it is a completely different ballgame.
Now when it comes to metallics that is another topic entirely. I have been told before that when you are painting single stage metallic, you want to use a siphon feed because HVLP guns don't have the pressure necessary to push out metallic flakes. You will get a much better finish out of a siphon, and in some cases this applies to solid colors as well because gravity feed guns can clog. The words used to describe it to me were, they have a tendency to bottleneck like a ketchup bottle and this is especially true with metallics. Not really a problem if you're using base and then you'll be clearing over it, but you're not going to get an even flow or finish with a gravity feed and HVLP will not be enough pressure. The point of me explaining that was to showcase how the standards the industry has adopted is saving on material and costs, and not necessarily to produce better jobs. In other words, you can get as good of a job if not a better job using a siphon feed in the hands of a professional. You're just going to waste more material.
Of course I don't mean to say it's not possible to get a good finish out of an HVLP, and I think we would agree that any gun in the hand of a competent painter can produce good results. It further proves my point, that the guns we used in the past are just as good as the guns we use today in my opinion and the opinion from many I talk with. I was really approaching this debate asking the question, have we really improved? Is it possible to lay down amazing paint jobs with older techniques? This is all really my opinion, and I don't really see it being talked about a lot and it's a little controversial. I understand it's not a very popular one, but since I left insurance work I will never touch another base coat product again and especially the tragic water based that are flooding the market.
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Sparky
Promoted Users
Hi BenKlesc,
I love this forum, the members are excellent, and a special thanks to all the experienced who take the time each day to share their knowledge on here. Respectful discussions where opinions may differ are also excellent learning experiences. I look up to alot of members here, some of whom have responded to this very thread. I have hardly any real experience working with either type and am trying to understand these statements and learn, but I have questions.
"I've always believed clear coat is essentially single stage urethane with no pigment. It drys in the same way single stage products do. In essence, clear coat is essentially no different from single stage."
As a novice I am confused with this statement. Thinking critically, if both SS and clear are essentially the same minus the pigments, why would Clear scratch more easily? Do the pigments of SS provide a harder less prone to scratch surface?
"The difference being that it's easier to buff single stage than clear. With clear you can only go so far."
If as you say, clear scratches more easily, and SS is more durable and less likely to scratch, then why would SS be easier to buff than clear. It seems contradictory to me.
I love this forum, the members are excellent, and a special thanks to all the experienced who take the time each day to share their knowledge on here. Respectful discussions where opinions may differ are also excellent learning experiences. I look up to alot of members here, some of whom have responded to this very thread. I have hardly any real experience working with either type and am trying to understand these statements and learn, but I have questions.
"I've always believed clear coat is essentially single stage urethane with no pigment. It drys in the same way single stage products do. In essence, clear coat is essentially no different from single stage."
As a novice I am confused with this statement. Thinking critically, if both SS and clear are essentially the same minus the pigments, why would Clear scratch more easily? Do the pigments of SS provide a harder less prone to scratch surface?
"The difference being that it's easier to buff single stage than clear. With clear you can only go so far."
If as you say, clear scratches more easily, and SS is more durable and less likely to scratch, then why would SS be easier to buff than clear. It seems contradictory to me.
Here is how I make a single stage.
I make a batch of clear, I add about 4 lbs of a dispersant per 100 gallons of clear, then I add my tint load, blend test, and package.
Food for thought.
Tints do nothing but give color and hiding and have no strength, so the tint load depending on the company is 15% to usually a max of 28%.
So just some info for thought to form your own opinions.
I
I make a batch of clear, I add about 4 lbs of a dispersant per 100 gallons of clear, then I add my tint load, blend test, and package.
Food for thought.
Tints do nothing but give color and hiding and have no strength, so the tint load depending on the company is 15% to usually a max of 28%.
So just some info for thought to form your own opinions.
I
A lot of bad info here but you are 100% right.
Something from class many years ago.
Ss has pigment exposed to the elements unless cleared!
Could we say pigment load weakens the strength, kinda like adding flattener???
Just food for thought as I'm not getting involved in this one as I hate to write long answers but common sense is prevailing from what I see.
crashtech
Combo Man & Mod
The SPI forums are, at their core, the place to come get help with refinishing issues, not a place to regurgitate dubious hypotheses on paint. I've made the mistake many times in the past of repeating things that I have read or heard, and it's mainly those things that have come back to bite me on the ass. So I've learned over many years that in the realm of tech advice, if I'm going to make a bold declaration as if a thing is true, I better damn well have experienced it myself. Otherwise such unproven info needs to be surrounded by maybes and question marks. This is something that @BenKlesc will hopefully learn before passing more misinformation on to others.