View Full Version : Any BASF/R-M experts? Need advice on products.

01-02-2009, 10:28 PM

I am restoring a GTO and will soon need to order some supplies from the local jobber. I only have access to Dupont and R-M, and have decided to go with the R-M line. My plan is to remove the old paint and take it down to bare metal, then spray a coat of epoxy, followed by fillers and/or a urethane primer surfacer as required, possibly another coat of epoxy, then UNO-HD single stage paint.

R-M has 2 different types of epoxy primers, one is the DE15/DE40 line, and the other is the EP589/689/789. I have read the P-sheets for both and the only differences I see are that the EP589/689/789 are chromated, and are mixed 4:1 compared to 2:1 for the DE15/DE40. (I am aware that BASF has discontinued the EP chromated epoxy primers and they are being replaced by chromate free versions (EP569/669/769), but I believe the chromate versions are still available to me.)

So.....my first question is which line of epoxy is better, the DE or the EP? Also, is a chromated primer better than non-chromated?

I want to use one of R-M's 2K urethane primer-surfacers, and it must be able to be flexed, as the nosecose on the GTO is rubber. From reading the different R-M P-sheets, it seems the DP25/26/27 Powerfill 2K is what I need, as it can be flexed with the HF08 additive, which I can also use when I flex the UNO-HD SS paint for the nosecone. I see the DP25/26/27 is recommended for DTM without any other primers and is advertised as offering excellent adhesion and corrosion protection by itself, but I have my doubts about using it without an epoxy underneath, especially on a complete restoration.

Am I on the right track, and is this a good choice for primer-surfacer? Does R-M have a better urethane primer surfacer that I should consider? This stuff is $$$ but I am willing to spend the money if it is good stuff. I could probably save some money by buying a cheaper urethane P-S for the steel body and buying just a quart of DP26 to be flexed for the rubber nosecone, but I don't know if I should bother, and I would prefer to use the same brand of supplied from start to finish if possible.

Thanks for any advice you can provide!:pray:


01-02-2009, 10:47 PM
I've used RM Diamont's color and clear but never their primers. However I do use a lot of BASF's Glasurit products, if your RM supplier can supply you with Glasurit I can help you out.

I have an extra BASF product CD that has the technical info for all their products. It should be a help with product info, I'll mail it to you on Monday. Be sure to read and follow the installation instructions.

OOPS, I lost your address please PM me with it or send it to len@autobodystore.com.

01-03-2009, 06:58 AM
Hi Len:

The jobber cannot get Glasurit. Unfortunately they know nothing about the products (it isn't really a paint store, it's a Carquest outlet that can get all the R-M products from their warehouse, and when I order the paint they will get it mixed at another store that has a paint department.)

I appreciate the offer for the CD, I will email you shortly.

I think member "Jimmo4life" has used alot of R-M products, maybe he has experience with their primers and can offer some advice.



01-03-2009, 02:25 PM
Hi mrennie,

I am quite familiar with those products. First off, the DE series primers are Etch primers & not epoxy. DE40 being discontinued (chromate version), DE15 replacing it. The EP series are your epoxy primers & would be my choice over the etch. Either way if you can get some chromate or chromate-free shouldn't really matter. The chromate versions being discontinued because of its toxicity, whether its better or not I don't really know.

Anyhow, the mixing ratio is pretty straight forward, 4:1:1 when your using it as an pre-coat under a urethane primer or polyester filler (that extra 1 is pnt88 reducer). The DP Powerfill primers are excellent primers & I have never experienced a problem using them direct to metal but you'll never beat the protection of having an epoxy down first. The urethane 2k will adhere beautifully to your epoxy if thats a concern.

The powerfill primers are your best choice, DP20 is only good for spot repairs and cant sit longer then 24 hrs before being topcoated. DP21 isn't that great..DP226 the low voc primer is descent, but it seems to shrink a bit, DP200 is awful.....I'd stay with DP25-26-27, you can also use this as a sealer too..(I'd recommend the epoxy/polyuroxy if you plan on sealing however)

When it comes to flexing, only flex what you need to (flexible parts), it will loose alot of its sanding/polishing abilities with that stuff in it. Do not flex your epoxy, it will not dry if you do.

Let me know if theirs anything else you need to know.

Where abouts in Ontario are you anyhow? I'm just outside the GTA.

01-03-2009, 03:44 PM
I jumped ahead a few chapters in a paint chemistry book I just picked up & glanced at the MSDS on the epoxy's. According to this author/chemist, nothing is as effective as a primer using zinc chromate, the chromate free primers use the safer alternative zinc phosphate. So if its worth it to your health, why not use the zinc chromate versions. I've used both & haven't noticed a difference. (epoxy's only EP589 & EP569). I can no longer get the 589 from my jobber.

I should also add just in case you are unaware, you cannot apply polyester fillers (bondo) over the DE or the DP Primers.

01-03-2009, 04:18 PM

Thanks, for the quick reply. I live in Cochrane which is 4 hours north of North Bay (8 hours from TO)

The P-sheets I downloaded last year showed the DE16 and DE17 as etch primers, but the DE15/DE40/DE49 products were listed on the epoxy chart so this is why I am confused between the DE15/40 and the EP. Regardless, the fact that the EP can be used as a W-O-W sealer or as Polyuroxy with the additives, I will go with the EP line. Have you found the EP to be a good epoxy?

I do plan on adding the flex additive only to the products I apply to the nosecone. Considering the DP25/26/27 are advertised as having high adhesion, they should work well (I hope!) applied directly to the rubber nosecone.

Something else I am confused about is that the P-sheets for the UNO-HD single stage say not to use EP epoxy primer under it as a wet on wet sealer...only to spray UNO-HD on the EP primers if they are used as a primer surfacer (I assume the intent to allow the epoxy to cure before having the topcoat sprayed on it). The P-sheets show that Diamont basecoat does not have this restriction and can be sprayed on the EP as a w-o-w sealer after 45 minutes.

Considering I will be working slowwwly and doing most spraying in stages (blast or sand bare metal, then prime with epoxy, come back another day and scuff epoxy, do filler work, spray DP26, come back another day and block sand, etc), the fact that they don't want you to spray UNO-HD over the EP when it is still wet (as a sealer) shouldn't be a problem, except when I do the bottom of the car and the firewall....I want to spray SC804 (which is UNO-HD factory mixed matte black), and having to scuff the bottom of the car after the epoxy has cured is going to be a major PITA due to all the nooks and crannies...I would actually like to spray the bottom and firewall with epoxy and then spray the paint without scuffing.

So here is the million $$ question: I know EP can be sprayed as a w-o-w sealer (4:1), and the P-sheet says once applied it can be topcoated anytime up to 24 hours after spraying before it needs to be sanded. Using the same mixing ratio for EP but for use as a primer surfacer, it says to let it dry 8-10 hours before sanding. If the UNO-HD is not supposed to be sprayed on EP when used as a w-o-w sealer (i.e., 45 minutes after being applied), will I run into adhesion problems if I spray the EP on the floor and firewall, wait 8 hours, then spray the UNO topcoat?

Sorry to be so long winded, but I tend to research the hell out of everything and considering the cost of the supplies I don't want to make a mistake or buy something I don't need.



P.S., have you ever sprayed UNO-HD and if so, what did you think of it?

01-03-2009, 04:48 PM
Maybe I'm not as familiar with the DE series as I thought :scratchch

I just had a look, I thought they were all etch primers ....being an epoxy guy I never really looked at them that much (assuming they were all etch). It looks like it has a much shorter pot life and I don't see anything stating it can be used as a wow sealer which is odd for an epoxy. Maybe its designed as a better sanding epoxy based surfacer, I see they recommend an etch precoat over the EP but not the DE when using over aluminum. My jobber doesn't even show it in their online inventor catalog. I'll call my rep on monday, see if he can tell me anything about it... now its buggin me!

The EP series I use constantly, it is a great primer. I use the polyuroxy additive over new parts & any other time i need a good sealer.

As for the nose cone, I'm not familiar with the car, I have no idea what its made of.. Is it a hard plastic? or actual rubber? You will likely need to use an adhesion promoter first, then apply your flexed DP primer over that.

I don't use singlestage to often & can't remember applying it directly over an EP epoxy. I would highly doubt you'd run into any adhesion problems, its just a urethane product like any 2k primer. I would suspect you'd either run into bleeding or dieback issues. Again I can ask my rep if he has some insight into that aswell.

Yes I have sprayed UNO on a few jobs and its a great singlestage. It lays down really nice. Most of my work is production so I use base/clear for the most part. I did spray my brother-in-laws truck front end in base/clear & rear with UNO (GM black) about 2 years ago, you wouldn't know any different. Just keep in mind you'll always have better UV protection with base/clear or by applying an approved clear over your UNO. If your planning on doing this much work it might be worth it.

btw, your plan sounds good. Sandblast, Epoxy, Sand, Filler, Optional Epoxy, 2 Komponenten urethane primer......you know the rest.

01-03-2009, 06:14 PM
Again, thanks for the info!

The nosecone is a rigid molded rubber..Pontiac was a bit ahead of everyone else to use flexible bumpers, and they were called "Endura" as a marketing name. They were basically rubber molded over a steel core and resulted in a nice looking front end without any steel showing.They first came out in 1968, and were used up to the early 70's before the switch to urethane bumper covers over top of a steel bumper instead of being molded onto a steel core like the one I have. From what I have heard, most guys have issues with the paint cracking several years after a repaint, even if using a flexed paint, so I am hoping that using a flexed primer surfacer as well as a flexed paint will do it for me.

I would appreciate it alot if you could ask your jobber about the DE15/40 vs EP589/689 (or 569/669) epoxies, just because I am curious, as well as why R-M states not to spray the UNO over the EP wet-on-wet, and if there is a specific time after the EP has dried that UNO can be sprayed without having to sand the EP first. I realize that if I mixed the EP as Polyuroxy instead I could go ahead and spray the EP wet-on-wet and then spray the UNO, but I don't know of Polyuroxy is as good corrosion protection as EP by itself, plus there is the added cost of the additive.

WRT base/clear vs single stage, I would prefer to use SS so I can paint the jambs and inner panels days before I do the exterior, and not have to worry about where the clear needs to go, etc. My other reasons are because the UNO and the DP26 use the same flex additive, and since I am repainting the stock solid red, I figure the extra work to do base/clear is not worthwhile.

Note that since I have never painted before except with rattle cans I am basically talking out my butt, but it makes sense to me...



01-03-2009, 07:16 PM
I read up a bit on the endura bumper, I'm not familiar with that material at all so I won't even pretend to be able to help you their. The flex additive should give you what you need in terms of resisting cracks, as far as surface prep I'm not quite clear if you can just sand it and apply your primer. If it were like a modern plastic that wouldn't be the case. So hopefully someone else can help you out with that.

The polyuroxy likely doesn't offer as good of corrosion protection as the pure epoxy form, but at the point when your using it as a sealer your bare metals been covered and its more to provide holdout over your repairs then protect the metal. You gotta keep in mind to that I'm in a production shop & I mainly use it because I know its better then a urethane sealer but doesn't take forever to flash like a normal epoxy. For you the regular epoxy hardener should be good.

Its too bad you couldn't get your hands on a Glasurit clear, you can mix and match products all ya like. Our shop is currently using RM EP569 epoxy, Glasurit 285-10/20 urethane primer, RM Diamont basecoat & Glasurit clears. Their 923-109 clear is pre-flexed and one of my favorites.

You can also mix & match singlestage/base-clear. Singlestage the jambs & base/clear the body. You can even mix the base into certain basf clears to make your own singlestage suitable for jambs. Singlestage over everything I'm sure would be much easier.

If you prefer I can put you in touch with my Basf rep, he can answer some questions for you and maybe find a way to get you some Glasurit if your interested.

01-03-2009, 07:28 PM
Hi jimmo,

That would be great if you could get me a contact number for the BASF rep, then I can figure this out and order my supplies. I want to order the epoxy and primer-surfacer soon in case it starts getting phased out as we switch to low VOC. Please email me at mrennie at onlink dot net

Thanks again, much appreciated!


01-03-2009, 07:36 PM
I just sent you his contact info to your private messages.I can email if you need.... He was on holidays last week but I still bothered him (didn't know or I'd of left him alone).... You can tell him I referred ya to him (justin jimmo). You can get him wound up if you want too, tell him I'm expecting my all expenses paid spectrometer anyday now (color scanner)!

p.s: I'll just let you ask him about the DE15/40 and ep under UNO. Let me know what he says.

01-03-2009, 07:43 PM
PM received...thanks Justin, much appreciated. I'll post whatever I learn when I call next week.