How Fuel Proof Is KBS Clear Coat?

[Brent Williams]

Has there been any data reported on the fuel resistance of KBS Diamond Clear Coat?  

Can it happily handle the 25-30% Nitro and castor oil used in 1/2a engines?

I would love to hear about some real world testimony in a high nitro environment.

[RknRusty]

Here's a quote from one of my highly trusted buddies posted on another forum. He is a self proclaimed high nitroholic, and also a member here at SH.
Rusty

Rustoleum paints are essentially enamel aside from those indicating lacquer. The auto paint is also listed as mineral spirit cleanup leading me to believe once again enamel base. I for one just don't understand all the experimentation. Why not use what works? Although most are building 1/2A's, high class finishes can be easily attained just by using what is formulated for the hobby. Many of the speed fliers due to high nitro use http://www.klasskote.com/. While some may feel this is very expensive, when compared to traditional dope finishes it really is about the same. WIth practice, I've seen these finishes equal in weight. A little goes a long way. Unlike rattle can finishes which are constantly changing formulation and vehicle components which deliver it out the can, products like Klasskote are consistent. As for sprayers, I've seen this product sprayed with professional like results from a $5 Preval spray bottle from Home Depot.

Another option is this http://www.kbs-coatings.com/DiamondFinish-Clear.html  Look under clear coats and also it's compatibility with other products. While most will cringe at the price, you get what you pay for. These products take out the guess work. I for one don't want to find out how my finish is now sticky and oil is creeping under it. I've been there. I've experimented with just about every product out there for the past 35 years. While I found many to be favorable, many have been removed from production or just went out of business. K&B Superpoxy was one of my favs. Nothing gave you the durability , shine, chip resistance as that paint. I feel Klasskote products even exceed the old Superpoxy.

The KBS products will work virtually over any paint system. I've seen it used but you must not be heavy handed. I've seen it applied with a spongebrush with excellent results. Although out of the price range of most, a little goes a long way and so will the duration of your models. Ken

[Avaiojet]

Makes no mention of auto two part clears?

[kenneth cook]

           Charles, I wrote that post and I have experimented thoroughly with 2 part auto clears. Most don't want to be fooling around with 2 part clears especially if your not adequately prepared to spray it and also have the proper breathing equipment. I can fully understand. KBS is a single stage product. Due to my experimentation for 1/2A fuels which are high in nitro, this led me towards finishes with adequate protection in mind. I didn't use these products for weight in mind. I have used several auto clears PPG Omni, HB 496 and a few others. Certain problems occurred using them such as the clear coat shedding from the underlying finish. This has happened on open bays which obviously are more flexible and fuselages. The shedding occurred in and around engine lugs and landing gear points. I can only speculate as to why this happened and more or less, I can say I was using one totally dissimilar product with another. Sometimes you win, sometimes you don't.

I've had quarts of auto clear harden within the can even without introducing the hardener. That being said, I didn't see this problem with the KBS clear. For those wishing to use this type of finish on a stunter, I would reconsider. I think it's a great product for the sport flyer as it gives a terrific gloss finish and durability. For those wishing to use it for a stunter, it certainly would have it's place in areas where fuel migration is a concern. My personal choices in the past few years have been water based polyurethane like Nelson Hobby paints. The new owner however needs to reassured that a whole community of users could be potential users and they're right here. After lots of practice and using it extensively I'm very happy with it. I like the fact it's user friendly and my house doesn't stink like solvent based paints.

[Avaiojet]

My personal choices in the past few years have been water based polyurethane like Nelson Hobby paints. The new owner however needs to reassured that a whole community of users could be potential users and they're right here. After lots of practice and using it extensively I'm very happy with it. I like the fact it's user friendly and my house doesn't stink like solvent based paints.

Kenneth,

Thanks for the other info and tips.

KBS has no odor or the water base paint has no odor?

I'm getting ready to clear two models and I'm holding off because of paint choice.

I found an auto body shop that will spray the two part clear, but they want 45.00 per model AND I have to have them all set up.

Which means I have to borrow Dennis' paint stand.

I figure, once I set up I might as well paint them myself. All I know is two part auto clear.

So, I'm really interested in all information I can gather, especially from those modelers with first hand experience.

[Dan McEntee]

Kenneth,


I'm getting ready to clear two models and I'm holding off because of paint choice.

I found an auto body shop that will spray the two part clear, but they want 45.00 per model AND I have to have them all set up.

Which means I have to borrow Dennis' paint stand.

   If they are supplying the paint, what are you waiting for? This sounds like a pretty good deal to me. It's their equipment so they get to clean it, they don't normally paint model airplanes so it's not unreasonable for them to require it to be set up but that's OK you got someone else's paint stand to use. No mess or smell at your house. They are professionals so you know that they know what they are doing. And you have all those "story boards" laying around that you test sprayed the paint on to test the clear. I'm still looking for the real down side to this, other than it will eliminate an excuse for you not finishing a model?
    I'm just sayin'.
   Type at you later,
   Dan McEntee

    Dan McEntee

[john e. holliday]

No worry, if they spray the plane like they do custom cars it will be too heavy to get off the ground any way, unless he has lots of air speed.

[Avaiojet]

   If they are supplying the paint, what are you waiting for? This sounds like a pretty good deal to me. It's their equipment so they get to clean it, they don't normally paint model airplanes so it's not unreasonable for them to require it to be set up but that's OK you got someone else's paint stand to use. No mess or smell at your house. They are professionals so you know that they know what they are doing. And you have all those "story boards" laying around that you test sprayed the paint on to test the clear. I'm still looking for the real down side to this, other than it will eliminate an excuse for you not finishing a model?
    I'm just sayin'.
   Type at you later,
   Dan McEntee

    Dan McEntee

Dan,

I don't need an excuse to not finish a model.

Another one of your pointless replies.

[Avaiojet]

No worry, if they spray the plane like they do custom cars it will be too heavy to get off the ground any way, unless he has lots of air speed.

John,

Auto body shops paint an incredable number of items related to that industry besides just cars.

That's a shallow outlook on the industry.

My background is painted graphics AND the restoration of sports cars. You learn what to pile paint on and what not to pile paint on.

So negative with your reply?

[john e. holliday]

I guess I'm a negative person.   If I can't do it according to my tastes, why pay someone to screw it up for me.

[Mike Griffin]

Brent I have been using the KBS Diamond clear for a while now and there is another thread on here that dates back a while that is entitled THANKS MIKE GRIFFEN (I spell my last name Griffin) but that doesn't matter..  That thread talks about KBS IF YOU WANT TO READ IT..  When I first talked to the tech people at KBS, THey told me this stuff was pretty much imperious to anything that would come in contact with it and I have found that to be true so far.  Fuel does not affect it.  

The other question that was asked a lot was how heavy is it.  I think we stunt flyers sometimes obsess a bit to much about weight however the KBS does add a little weight as all clears would. I have not done tests comparing it to the many other clear coats available and do not intend to as the difference in grams is not that important to me.

I tried to steer this thread back to answer your original question and I hope this helps.

Mike

[Mike Griffin]

Brent I have been using the KBS Diamond clear for a while now and there is another thread on here that dates back a while that is entitled THANKS MIKE GRIFFEN (I spell my last name Griffin) but that doesn't matter..  That thread talks about KBS if you want to research it..  When I first talked to the tech people at KBS, THey told me this stuff was pretty much impervious  to anything that would come in contact with it and I have found that to be true so far.  Fuel does not affect it.  

The other question that was asked a lot was how heavy is it.  I think we stunt flyers sometimes obsess a bit to much about weight however the KBS does add a little weight as all clears would. I have not done tests comparing it to the many other clear coats available and do not intend to as the difference in grams is not that important to me.

I tried to steer this thread back to answer your original question and I hope this helps.

Mike
[/quote]

[Brent Williams]

Mike, thanks for your reply.  I have read your posts many times extolling the virtues of KBS clear.   Those posts, and the fabulous results you and others have achieved have definitely convinced me that I want to use it on my larger planes that stay cleaner and use lower nitro content fuels.  Trust me, I am no stranger to the search function.  I believe I have read every word that has been posted about KBS clear here on stunthanger and also over on stuka stunt.  I haven't read any reports of its performance on planes equipped with messy Cox 1/2a engines, however.

Reed valve cox engines always have fuel and oil trapped around and behind the backplate which presents a strong challenge to even the most robust finish.

Maybe I'll just go ahead and purchase some KBS and test it with high nitro content fuels.   

[Mike Griffin]

Wish I could help Brent hut I do not fly 1/2A..

[Dennis Toth]

Brent,
If you try the KBS clear you can get the starter kit which is a small can (4oz) of clear. If you are thinking of spraying, get a small can of reducer. I did test some on my Yak Yak Bipe around the nose and over the edges of the MonoKote. So far the nose area which is paint is bullet proof. The edges of the film is also solid, no peeling. On the Bipe I just used a foam brush and put it on straight from the can. For a full ship I'd use dope for the base and color with a couple coats of clear dope then the KBS top seal coat.

Best,        DennisT

[Jim Roselle]

How long are users of Kbs diamond clear letting it cure? I made a test patch yesterday and let it cure for 24 hours. It has been cool (65*) and humid for the last 24hours. Cox super power 35% percent nitro just cut through it in a matter of seconds and turned it into a sticky mess.

Jim

[Steve Thomas]

How long are users of Kbs diamond clear letting it cure? I made a test patch yesterday and let it cure for 24 hours. It has been cool (65*) and humid for the last 24hours. Cox super power 35% percent nitro just cut through it in a matter of seconds and turned it into a sticky mess.

Jim

The instructions say it's hard enough after 4 days, and then continues to harden after that.  I like to wait a couple of weeks to be on the safe side.

[EddyR]

KBS may be fuel proof but it is not dope proof. If you do repairs and get dope on it it will craze,crack  or bubble up.

[Howard Rush]

Phil Granderson is now recommending KBS to seal bare wood.  He puts dope over that.  http://www.flyinglines.org/ptg.finishing.html

[Mike Haverly]

Phil Granderson is now recommending KBS to seal bare wood.  He puts dope over that.  http://www.flyinglines.org/ptg.finishing.html

As a matter of fact I just tried that system.  It works well.  Two coats of KBS, sand smooth and cover with CF veil.  Usual process from there.

[Jim Roselle]

The instructions say it's hard enough after 4 days, and then continues to harden after that.  I like to wait a couple of weeks to be on the safe side.

Just tested a patch after 4 days, still lifting. Will try again at the one week mark.

Jim

[Mike Griffin]

As a matter of fact I just tried that system.  It works well.  Two coats of KBS, sand smooth and cover with CF veil.  Usual process from there.
[/quot

KBS is also lighter than dope.

[Jim Roselle]

Here's my experience with KBS diamond clear and Cox Super Power 35% after a 2 1/2 week cure time:


I decided to test power master 10/22, this is about a 15 second exposure:


In my experience KBS  Diamond Clear is in no way "fuel proof" by any interpretation if the term "fuel proof". Do yourself a favor and save the 50 bucks.

Jim

[Eric Viglione]

Here's my experience with KBS diamond clear and Cox Super Power 35% after a 2 1/2 week cure time:


I decided to test power master 10/22, this is about a 15 second exposure:


In my experience KBS  Diamond Clear is in no way "fuel proof" by any interpretation if the term "fuel proof". Do yourself a favor and save the 50 bucks.

Jim

If you want something 35% hot fuel proof, you want a 2 part paint like epoxy or urethane. Epoxy clears tend to yellow over time, so that leaves urethane.

Not gonna be happy with any 1 part I know of, not reliably. And even with a good 2 part paint, I have still seen damage like your first photo.

You have to seal all the edges, even inside the cowl and especially the lip, because if the fuel finds a way UNDER the edge of a chip, a pinhole, or something, it will prune up just like that going aft.

Burned fuel is also a different animal, the acidity in fuel that has been through the exhaust can hurt paints that can laugh off nitro. Isn't chemistry fun?

Well, that's my .02 cents, adjusted for inflation of course.
EricV