Sterling vs Awlgrip

[brminc]

Are the catalysts for Awlgrip topcoats interchangable with Sterling topcoats?
Can Alwgrip reducers be used with Sterling primers and topcoats as well?

[PAR]

It's unlikely that Sterling or Awlgrip will provide this information, though a stroll through their respective documentation will possibly yield some insights, for the chemically inclined. They both are LPU's but having used both, they aren't the same. They smell slightly different, dry differently, have a different gloss and application though very similar is easier with Sterling then Awlgrip. This suggests at least some chemical differences, though compatibility may still be possible.

The only sure fire way is to try a few small patches and perform scratch tests.

[Jimbo1490]

You really should have posted this question to the thread
"The Awl Grip knowledge challenge" But I'll go ahead and give you my opinion based on experience.

Yeah, they are pretty much interchangable. You might as well throw in Jet-Glo while you're at it. We used to NEVER buy Awl-Grip/Alumi Grip catalyst because Sterling was about 10% cheaper always. So we used it interchangeably for years. Shot literally hundreds of gallons of 'Grip that way. But that's changed and now they are about the same price; Sterling was even a bit higher last time I looked (2005). You can use the reducers interchangeably as well, though I do not know why you'd want to use Awl-Grip reducers as the Sterling counterparts are just better. We really like Sterling 1014 reducer and use it in just about everything. Sterling cat tends to favor cold weather more than Awl-Grip and will more easily solvent pop on you in warmer climates, so seeing you're way up in the great white north, you'll like Sterling cat (and the whole line) better than 'Grip. The Sterling reducer tends to reduce this problem in Awl-Grip topcoat, which is one big reason we like it.

Jimbo

[brminc]

Thanks, I'm new to the forum and my sense of protocl reflects that. My interest is my project is scheduled with Sterling topcoats but I have some Awlgrip catalyst and reducer from a previous project I would like to use to economize if there is compatability

[PAR]

Jimbo, check you Sterling pricing again. I just picked up a few gallons and it's a fair bit cheaper then AwlGrip. I'm getting it from Joel out in Vero Beach. I've never liked AwlGrip in comparison to Sterling anyway, so I'm probably biased.

[Jimbo1490]

Thanks, Paul. We were getting pricing from Merritt, last I recall. We've since completed a switch back to PPG (from whence we came) and will probably never go back to the 'polyester' urethanes like 'Grip, Sterling & Jet-Glo again. I can save 30-40% using PPG and it really has NO BAD HABITS! Easiest paint to shoot, ever!

Years ago, (1992) we switched from Awl-Grip to PPG's polyester urethane, 'Durethane' (DU), mostly out of convenience since a dealer was one (1) block away from my shop. But we soon discovered that it was a real pleasure to work with the stuff! 4 different hardeners & 3 different reducers plus a retarder, and all the support chemicals worked in their other paints lines, so never any waste! In all the DU jobs we shot I can never remember a single instance of solvent popping, not even on a run or double coat spot (and we were located in Miami at the time); it was just that good. It had a lot less 'die back' than the others and was much kinder to masking tape, a chief complaint about the big three (they all attack tape glue rather aggressively) And did I mention? Over 1000 colors in their fleet catalog Vs like maybe 100 for the 'big three'.

But all good things must end, and PPG discontinued DU back in 2000 due to EPA regulations that hit sellers of (primarily)'automotive' paint. The big three call themselves 'industrial/aerospace/marine' paints and are able to skirt these tougher regs, even though they might be for sale on the same street, maybe even in the same store. So we went back to shooting mostly Awl-Grip, with a few Jet-Glo jobs here and there. (It was a sad time; our PPG rep STILL gets choked up when we talk about it )

After a couple of sputters with DUT & 'DUHS', PPG finally successfully replaced DU about 2004 with "Delfleet Evolution" (FDG) and the high-solids version, FDGH. The fleet colors have expanded to over 3500. And this stuff is the only polyurethane enamel I have ever shot that handles metallics perfectly while simultaneously achieving high gloss, so you can shoot a metallic color without really needing to shoot clear if you don't want to. And with the high-solids version, you really can do a one or two coat paint job; you can shoot silver over orange or red or screaming yellow and get full hiding in ONE COAT.

Can you tell I like this stuff?

Jimbo

[PAR]

Jimbo, you should really come out of your shell man. Speak up if you like something, don't just sit there . . .

I was a PPG guy too . . .

[eponodyne]

How's the toxicity? Is this something for the home handyman or will it kill you stone dead if you look at it while the moon is full?

[Jimbo1490]

There's no paint I know of that'll "kill you stone dead if you look at it while the moon is full?" All of the two-part polys contain isocyanates, this one is no different. If you're not allergic to the stuff, just use 'good industrial hygene practice' and don't worry about it. The same thing goes for epoxy, BTW. If you are allergic, simply abstain from using or handling these products AT ALL. 3M 5200 contains isocyanates, too so allergic persons should not use or handle that product either.

Jimbo

[Kaptin-Jer]

Jimbo,
We (my office) switched to specifying PPG concrete coatings because of their lower VOC. It might be the same with their 2 part (but I doubt it)
In regards to their 2 part. Do they have a brushing reducer? Have you heard any feed back from anyone rolling and tipping. I'll check out their catalog at the office, but I would like to hear some user feed back.

[Jimbo1490]

Delfleet is a low VOC formulation. The 'high solids version is very low VOC. We are getting measured film builds from one coat what took two coats of Awl-Grip, because it has very little solvent. Sorry, no it's NOT for brushing.

Jimbo

[mastcolin]

Great, I spend 4 years getting a chemistry degree, work time in a development lab for yacht paint supplier...and you guys just mix and match

You can use the various convertors with various bases but a) you will mess up mix ratio (I'm not talking about the volume mix ratio,I am talking about the actual chemical mix ratio). I can"t remember the numbers and I can"t be bothered to look at data sheets but you'd be lucky to get the right numbers. b) the unplanned solvent blends may give you issues (popping, blush, dulling).

The reason jimbo got more flow using sterling cat was probably just due to fact that it had less isocyanate and more thinner in the can.

The products are formulated to gave broad application performance with known result in physical film. Messing around may suit some individuals but won't be applicable in the main. eg jimbo sprays way different than me who sprays way different and under different conditions than say the guys in Majorca.

I would strongly urge any painter not to mess around with the products (if it goes wrong it will be found out and then you will have to explain to your customer what the hell you were doing)

You wanna save 10% price on half the product for the risk? Interesting. Here we bill the customer for the job. How about you bill him the price that the product costs. How come you need that 10%? (mmmm, stupid question having seem the US economy lately)

Jet-Glo is great but we probably prefer Alexseal these days.

[Jimbo1490]

The 'big three' polyester urethanes are very close to their respective stoichiometries when the catalysts are interchanged. But all urethanes will harden properly over a fairly wide range of mix ratios on either side of stoichiometric. The bigger issue is actually having the proper type of isocyanate (API vs HMDI vs TDIM). The polyester urethanes all use the same type (API), which is why the activators interchange rather nicely.

If you had a background in automotive refinishing, you would know that there are 'universal' polyurethane activators available that work handsomely in the product offerings of many different companies, often offering both superior application and cured state properties. It frankly baffles me that Tremco or Tanstar have not yet seen fit to offer a universal polyester urethane activator, since there certainly is a market for such a beast. None of the presently available universal activators is AT ALL compatible with polyester urethanes and will turn them into garbage in as little as 5 minutes after mixing. The Tremco and Transtar products are typically 1/3 to 1/2 the cost of say Dupont V192S, so the savings is significant, not an admittedly trivial 10%.

As for reducers, as long as the reducer contains no more than a small fraction of ketones and is mostly esters, it will be compatible with most any urethane, especially if you stay away from 'very slow' formulations.

The reducer for Imron 333 is simply a mix of naptha and toluene. Quite a few shops adopt 'one reducer for all' since this practice tends to homogenize the application properties of different products. Sterling 1014 is a favorite as a 'universal' reducer. We use PPG's DT 895. Works in everything.

Jimbo

[mastcolin]

What you said jim is sorta correct. However my point is that you shouldn't be mixing stuff together unless you know exactly what you are doing. As you mentioned with solvents and catalysts, what seems a good idea isn't.

1) you mentioned 10% price difference in catalysts between Sterling and Awlgrip
2) Awlgrip catalyst is HMDI based
3) sure most polyester will go hard with broad range of curing agent - this isn't the same as being optimally crosslinked ie you will get lower film performance eg lower durability, poorer physicals. I imagine Sterling will go hard with about 20% curing agent given its nature.
4) Even the smae chemical will give you differences depending on its source. At Akzo Nobel (makers of Awlgrip and International and Sikkens automotive to name a few), the raw material is single sourced. It minimises batch to batch variations.

Sure you can use 'universal curing agents" - but why? You would negate any warranty. As I said, use the correct curing agent at the correct ratio. I couldn't care less if I save 100%. I'm not taking risk on 80m Feadship. You can go ahead doing cars on the cheap and taking the risk. (Actually what you have told me perhaps explains all the appalling resprays I notice)

10% difference in crosslink ratio, you will notice. There is built in factor for moisture in air and age but don"t ask another 10% variable on top. It doesn't make sense.

I just don't think that telling people on this site that anything is possible is good policy.

ps nowt wrong with ketones in polyesters. It's what Awlgrip T0001 and T0003 are mainly made up of. But this gets back to my point. Some manufacturers put the strong solvent ie ketone in the base and use weak solvents in thinner - when it is mixed up at correct, specified ratio it is good blend. You mix up other companies' is possbile but it ain't worth the risk.
I'm not long back from France (60m, black Alexseal), the heathens there put fruit cordial in their beer!! This is wrong, wrong, wrong.

[Jimbo1490]

Yeah, it's all going to depend on the job at hand. We just won a bid on a Falcon 20 for $56K and you bet we won't be mixing up any unknown recipes on that shoot! But there will be many little sub sessions where we will shoot many different small parts and panels seperately, door break in markings, the airstair and many others too numerous to list. Sometimes we'll use 'special recipe' paint for less critical items like these.

FWIW, I have never seen a failure of, for instance, Awl Grip which was attributable to using Sterling Cat. Not even after several hundred gallons over 20 years. Certainly there would have been ONE job that failed along the way if there was going to be a problem. A certain supplier here in FL regularly sold us Sterling cat for our Awl Grip and even recommended it. They intimated that they sold 2-3X as much Sterling cat as 'Grip. Sterling was $71 while 'Grip was $110 at that time. The difference is trivial now, but $40 is still dinner out

You're right about the HMDI vs API; I got them mixed up. The polyesters all use HMDI (just checked labels) while Imron and its relatives use API.

If you're going to worry about optimum cross-link, you'd be advised to steer clear of accelerator as well, as it is known to shorten the life of the coating. Both 'Grip and Jet-Glo reps advised me so. I had heard this way back in the '80's from a DuPont rep as well.

Jimbo