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we'll be replacing the rubber on our '40 kc 1/2 ton soon and think this'll be a good opportunity to get the wheels looking fresh...they're a bit rusty now & have been painted at least twice...

any comments as to the best procedure & finish for a daily driver?..

epi

Powder coated mine and they've held up and look great.my car is black though,color match is always a challange as we've seen many times here!!!chef-

I've been reserching this myself, as I'm preparing to paint my frame and wheels soon. Perhaps someone will answer this question for the both us us. I'll start out with what I propose to do, and maybe someone with experience will comment:

1) Degrease wheels prior to grit blast. I've thought of using "Gunk" Engine Brite for the heavy stuff, but maybe it's better to use a biodegradable "degreaser" (like the product from Genlabs of Chino CA). (Note that I'm a little concerned about this step because it will result in petroleum products being washed down the sewer system, which will eventually find it's way into someone's drinking water). Then there's the official grease and wax removal products from the paint manufacturers, like Dupont 3900S (First Klean). I guess the key here is to completely remove all contaminants BEFORE abrading the surface to avoid driving the contaminants into the metal during the paint removal process. I wonder how many people actually do this step!

2) Grit blast with 40 Mesh Industrial Quartz. I've done this using a grit blast cabinent from Harbor Freight with my shop vac hooked to the vent tube. Note that this process results in a huge amount of "free silica" in the air even with the vacuum cleaner running. As everyone knows, breathing free silica can result in silicosis (sp?), which in turn results in less time to work on your Chevy. Thus, maybe you want to pay someone to do it with the proper safety equipment

3) Re-clean the surface. Dupont recommends their 3901 "Final Klean" for this step. I wonder why you can't just use 3900, since you've already bought it? If this doesn't make you blink, I see that Dupont has several other cleaning products. I'll bet just following the process outlined here with a single cleaning product will result in a 200+ year paint job!

4) Coversion coat the bare steel. I understand that this is typically accomplished with phosphoric acid dichromate. I have a product from JASCO that is availble from Home Depot, but the local paint suppliers have similar materials for treating bare steel. For instance, Dupont's website recommends the use of a metal conditioner (Dupont 5717S), followed by conversion coating (Dupont 5718S). I might go this route, particularly if someone recommends it as being preferred over the single step JASCO product.

5) Epoxy prime with Dupont 2580CR (Chromate).

6) Topcoat with DuPont ChromaOne Acrylic Urethane Single Stage. A friend (OlChev on this site) has recommended PPG DCC 9300 Black (a single stage urethane topcoat). He says it is "is truly black and not charcoal". What I wonder is about the proper gloss: not-too-flat but yet not-too-glossy. OlChev also recommended using Dupont's Veriprime as a self-etching primer instead of doing the conversion coat step. This is probably simpler than my outlined method, and likely provides the same result for less money. On concern I have is that I want to stick to a single manufacturer to assure compatibility.

Anyway, that is roughly what I thought I'd do.

If you like, one of my wheels has an indication of where and how wide the factory pinstripe was. I could take photos and document this for you (I was going to do this for myself anyway, just not now).

Hope this at least gets us started!

I've been painting my '24 Chev chassis and here's what I've been doing. Extract what you can use. The frame was sandblasted, but I've been having a lot cleaned by a local "stripper" in a caustic soda bath. It really cleans with no removal of metal. Metal prep or a good wire brushing for a final cleaning before coating with a self-etching primer. Highly pitted pieces were further coated with primer-surfacer and sanded. Final color is PPG Concept DCC acrylic urethane. The paint is easy to apply, hard to run, quick to dry. It is extremely high gloss...wet look...and quite tough. The color is true BLACK. Not cheap, though, at about $150 per gallon, plus catalyst and reducer. It does go far, though. I've done the entire chassis and a lot of little pieces with 3/4 gallon.

I have sand blasted 20" 2ton truck rims with small HF pressure blaster

a lot of good ideas, guys...keep them coming...

chef, I was thinking at one time to powder coat for durability, but not sure if I shouldn't keep things as original as possible...that's our plan (the boys & I), to keep everything original where possible, give a little in areas that make a better or safer daily driver...

lenn, what a plan!..would love a jpeg of the pinstriping...

tom, your plan is do-able for us...is the high gloss correct to original?..like you said, the paint's not cheap, but does go a long way...

johnny f., so, you'd color coat all but the final, have the tires mounted, then go for the finish?..how well do the masking rings work to protect the rim during mounting?..seems like there'd be a lot of friction from the installing tools...

thanks again,

epi

Chevrolet,
The "masking rings" just protect the tire from getting paint on them.

lil' johnny,

oh, yes, I have seen those masking rings...right...

epi

Ditto on Grumpy's excellent post!

I would not recommend powdercoat. Since you are using the truck as a driver, nicks and chips are inevitable. The powdercoat is too difficult to repair, and rust will creap under the coating and lead to delamination.

Then you will be "blasting" the wheels and repainting down the road....

I would not complete the phosphoric metal conversion - go with the acid etch primer. Easier and better results.

Hey bowtieollie, sounds like you've been down this road before!

I was wondering about the conversion coat step: Let's say you can't apply the acid etch primer right away, and you live in a humid climate. You decide to conversion coat first to keep the rust flowers from starting. Then you apply an acid etch primer two or three months later (with no additional preparation).

My question: Is the acid etch primer still able to do anything useful at the surface? (I think probably not because the chemical reaction has already occured, but I'm asking)?

I like the idea of skipping the conversion coat step also, but wonder why the products are still offered.

Luckily for me, Utah is pretty darn dry so I don't really have to worry about this, but I am curious how this all works!

bowtie ollie & grumpy,

so we're deleting the jasco/dupont 5717s & 5718s and substituting the veriprime instead in grumpy's step #4?..

epi

I think it depends on if you are going to have the parts primed very shortly after they are grit blasted or not, but let's see if anyone weighs in on my earlier question.

I'm having my wheels dismounted today, and will see if I can take the pinstripe pictures tonight. Only one of 9 wheels has the stripe, and it's buried under a coat of black paint so I'll have to abrade the black off to really get at it. One-half ton forensic work, I love it! (I just couldn't get into it as much with a car for some reason!)

I want to rent a booth and paint as much stuff as possible at the same time. I'll have the hardware to build 5 disc wheels for the '31, and hopefully 5 "standard" wheels for the '37, plus the '37's frame, and maybe other '37 hardware to paint. Since it will take forever to get all these parts prepared for prime/topcoat, I'll have to do them slowly, then batch the prime/topcoat step. Even though Utah is dry as a bone, I suppose it's better to do the conversion coat immediately after blasting if you have to wait like I do (and I'll bet most of us are in that boat together).

But I'd like to hear if anyone knows different... :confused:

I'm going back out to the garage!

OK Chevrolet, here's your stripe photo:



It's just a shave over .2" wide.

grumpy,

thanks...looks like about 1/4"...

epi

I guess... I think they were painted with brushes, so it probably varies between here and there.

Some paints are "harder" than others, but they are more difficult to do chip repairs on, plus some are more difficult/dangerous to spray.

So which paint would be the best one to use on wheels? What system do you guys like the most?

The advice I've received is to use a single stage urethane. It's easy to repair and tough. I've been advised against Imron as being too brittle, and against powder coating. I can't remember the exact reason for not using powder coating.

Thanks for your help.

HI Grumpy,

Yes, I have been down this road. Several years ago, when powdercoat was really starting to take off, I had several undercarriage parts coated.

Well, that was 1987. Today, all the powdercoat is gone. Replaced with a single stage urethane that is actually holding up better.

In regards to the conversion coating vs the acid etch primer.... there are some concerns with adhesion and the possibility of "too much acidic" material being applied on the base metal.

The conversion coating is a phosphate process to reduce the chances of oxidation. The acid etch primer, literally attacks the base metal to improve corrosion resistance and bonding. The can be a chemical reaction between the two systems that may result in entire painting process failing.

What I have done with perfect success is to spray a light coat of acid wash after the media blasting. Since the acid wash is not used to hide or fill any metal imperfections, the coating is "almost" transparent. This prevents any oxidation until I have had the opportunity to prime and paint.

In regards to the paint system that works most effectively on wheels, I prefer single stage urethane. Base coat/clear coat is a excellent system, but with the routine maintenance required of wheels, the thinner mil thickness of the single stage just lends itself to a better performance. Its easier to touch up, doesn't seem to be as sensitive to wheel weight removal, etc...

Hello BowTieOllie...

I haven't begun to sandblast my wheels yet, I'm still cleaning the frame and working out how to repair worn-out spring mount eyelets. I have that process lined up now, I just need to make it happen.

It's not too late for me to do this with any of my parts (hopefully it's not to late for Kepi or Gator either). I really don't want to have to redo the chassis paint, expecially after working through it and concluding that I know what to do!

It sounds like you are referring to something like:

Dupont 5717S (Steel and Galvanized Refinishing System Conversion Coating)

Or would you use something else?

I really appreciate your help!

grumpy & bowtieollie,

no, not too late for us yet...keep the posts coming...if we can drag our feet, we're hoping you'll lead the way on this...

epi

We'll see who gets there first... you don't necessarily want to wait for me, as your son's might be married with children before my wheels are painted!

grumpy,

I hope you can move a little faster, ok, buddy?..

epi

Yes that is the DuPont Conversion Coating I would use.

But - only if using an epoxy or urethane primer.

If using an acid etch primer - there is no need for the conversion coating. A few paint mfg will actually state - not to use a conversion coating with their acid etch primer.

I know this may sound a bit strange - but if the acid etch primer is not applied according to the product sheet - it CAN cause a corrosion problem.

Cool! I'll give this process a shot. Maybe I can document it and we all can co-author an article for the G&D (or the Kearns/Taylorsville Times, which always welcomes short, well written technical articles)!

Next we have to work on how to apply the pinstripe...