*Lazy Builder Question* Primers

Having made every other decision possible (Tipup/slider, TW/NW, -7/-9, SB/QB) I find myself not so conclusive on primers. I'd like to use a good self-etching primer throughout the inside of the airframe, mostly because I'm lazy and don't want to Alumiprep/Alodine a whole mess of parts. I'd like to shoot out of a gun (2-part is fine with me). I'm assuming the nice hard epoxy primers like the AZKO need the conversion coating (from what I've read).

So my question, from my description of my desires, is the SW self-etching wash primer what I'm looking for?

I'm waiting on this and tools to start building now .

I am using DuPont VariPrime, but will likely switch to Nason. It is DuPont's secondary line. It works similarly and costs less. You can get it in most car part store/auto body supply places. I dunno if it comes aerosol. It may?

Check it out.

CJ

Stephen,

I was lazy as they come when it came to priming 'Flash'. Rattle can self etching primer standing in the front yard with the wind at my back. A VERY light dusting of primer was all she got. It should only last 30 years or so <g>. It was called 'Marhyde' and was bought at a local English Color paint store.

Best,
Doug

osxuser said:

Having made every other decision possible (Tipup/slider, TW/NW, -7/-9, SB/QB) I find myself not so conclusive on primers. I'd like to use a good self-etching primer throughout the inside of the airframe, mostly because I'm lazy and don't want to Alumiprep/Alodine a whole mess of parts. I'd like to shoot out of a gun (2-part is fine with me). I'm assuming the nice hard epoxy primers like the AZKO need the conversion coating (from what I've read).

So my question, from my description of my desires, is the SW self-etching wash primer what I'm looking for?

I'm waiting on this and tools to start building now .

Click to expand...

i'm lazy too, and did exactly what DR did (front yard and all...). i am using NAPA 7220 rattle can.

Sherwin Williams GBP-988, same stuff

Sherwin Williams GBP-988 is basically the same stuff as MarHyde and NAPA 7220. Check your local Sherwin Williams *automotive* store. I know the ones in Ontario and Norco stock it (probably among the closest SW sources to you).

I used AKZO on most of my airframe stuff when I built my -7. Then I switched to GBP-988 and never looked back. My next plane will have minimal primer. Just a light coat of 988 on the flanges and lapped joints.

)_( Dan
RV-7 N714D
http://www.rvproject.com

I've seen airplanes that are 30+ years old with no major corrosion problems. That's why i'm not too worried. I was worried about the rattle can being just a bit too pricy. I was planning on priming ribs and spars, but not skins. I considered just the Temco Zinc Chromate since I use it for my job, but it's a bit pricey.

One of my local automotive paint shops carry SW-988 for 8 bucks a can. I use it on the smaller parts. Nason on the big items.
Steve

Stephen,
I have been using the SW wash primer on airplanes for over 25 years without a problem whatsoever. This is also the same primer that Vans uses on the quick build kits. Now, having said that, if you are really lazy as you state, unless you live on the coast or other high salt enviroment, you really don't need to prime inside at all. The aluminum used in the RV kits is either 2024 which is al-clad or 6061 which is very corrosive resistant. The biggest reason for priming is for resale. People buying an airplane see no interior priming as an excuse to talk you down on price. I have inspected many very old Cessnas that have no corrosion at all. Advantages of not priming are cost, weight, time and work.
Mel...DAR

That's what I'm doing, too

dan said:

Then I switched to GBP-988 and never looked back. My next plane will have minimal primer. Just a light coat of 988 on the flanges and lapped joints.

)_( Dan
RV-7 N714D
http://www.rvproject.com

Click to expand...

That's what I'm doing. Also, if there's a scratch, I apply some GBP-988,

//The biggest reason for priming is for resale

I hear this a lot (and I believe it) but where RVs a re concerned, I've never seen a percentage figure attached to this. Are there enough RVs for sale that buyers dictate the market or is the market dictated also by what the seller is willing to sell for?

I ask this because it seems to me a seller might self-depreciate the airplane because it doesn't have primer, even though he/she/it knows that other than reslae "value," there's really no value in the priming (as stated).

In other words, sellers ask for less because of a buyer's perception. Now if a buyer can just drive a couple of miles to the next RV aircraft ror sale, then I suppose you've got a competitive problem in establishing a selling price and maybe it all hinges on whether something is primed or not.

But if priming really enhances value, shouldn't it be on the basis of something tangible?

I have no clue at all what the resale market is for RVs but I wonder if sellers routinely "discount" on perceptions or stabilize the market value merely by saying "no" when a buyer says "I'll give you $XXX less than what you're asking because there's no primer."?

I'd make a lousy car salesman, I suppose.

we have two or three SW stores here, and none of them had GBP-988, which is what i was going to use in the first place. they could ship it to me, but then i'd have to pay hazmat. for some reason, they wouldn't ship it to their store (could've been the lousy salesman being lazy!)

napa didn't have 7220 in stock, but could get it to their store overnight. i buy it in boxes of 6 cans, and it runs $26/box. great value!

The SW wash primers is sold in the industrial coatings stores. In st. Paul, I can usually go into the auto coatings store and they'll get one sent over from the i.c. store in Minneapolis. Forget about the regular SW paint stores; they're worthless.

Closest ones to you look like Oswego and Peoria.

You can find the nearest industrial coatings SW store here.

I'm using SEM-solve wash and SEM self etching primer. works great.

The stuff you actually do need to prime, IMHO, is what Van's tells you to,
like the non-Alclad reinforcing angles, rudder control horn, that sort of thing.

I can't stand priming. I'm doing as little as possible.. Light coat, just to
protect the metal a bit, then moving on.

dan said:

Sherwin Williams GBP-988 is basically the same stuff as MarHyde and NAPA 7220. Check your local Sherwin Williams *automotive* store. I know the ones in Ontario and Norco stock it (probably among the closest SW sources to you).

I used AKZO on most of my airframe stuff when I built my -7. Then I switched to GBP-988 and never looked back. My next plane will have minimal primer. Just a light coat of 988 on the flanges and lapped joints.

)_( Dan
RV-7 N714D
http://www.rvproject.com

Click to expand...

Ditto....I switched from AFS Waterborne Primer/Sealer to AKZO (I had used the AKZO previously for an non-aviation related project and really liked the stuff). I just finished my rudder, though, and I thought about all the time I spent etching and priming, cleaning etc. It's ridiculous. I also just decided to switch to GBP-988. It's liberating.

Our Sherwin-Williams store here locally doesn't carry 988 spray cans either but an auto parts store that carries their brand of automotive paints does have it. Our Sherwin-Williams store only carries products for home and industrial and not automotive.

Hope this helps

Being a total newbie, I have spent atleast the last year or so
reading posts and checking out websites. I believe that some level of priming is required, but not every last part. To that end, I decided just to use an aerosol primer. The primer I decided to use is GBP 988. I cannot see spending all the time some are spending priming when real work could be done. I also believe what I build will probably outlive me , even if I didn't prime anything.
Anyone looking for GBP 988 should go here:

http://www.sherwin-automotive.com/company/store_locator.cfm

Just insert your Zipcode and find your nearest stores.

Greg Piney
RV-8 SoonToBe
Shop almost ready

I agree with you 100% Mel, I live in Socal, but in the next 5 years will probably hangering out in the desert, so I'm NOT worried about corrosion. I will probably end up selling this one a few years down the road (I know it's not going to be perfect enough for me). Primeing the ribs and such will make it LOOK much better to potentual buyers, which is why I would do it in the first place.

If I was gonna keep it forever, it'd just get Zinc Chromate on the non-alclad parts and leave it at that. I've actually considered getting the powder coating that is on the steel parts blasted off and just prime/epoxy paint those since powder coating hides cracks real well. But being this one is gonna be sold eventually, I'll just leave the factory coating on it. It's all about the looks for most buyers. After working with on several pre-buys with people, I'm convince that most buyers know whether they are going to buy an airplane 5-minutes into the prebuy, no matter what the mechanic says.

So long story short, prime the ribs with a rattle can it is. Thanks

As the saying goes -->
Bondo and paint... makes things what they ain't.

(In A&P mode, kinda)

What was/am I thinking?

jcoloccia said:

It's liberating.

Click to expand...

I read stuff like this and I wonder what the hell I am doing with the PPG DP48LF 2-part (3 w/ reducer) pain-in-the-ass primer!?!? I tried the SEM for some small parts, and loved it. Note to self: Buy more SEM!

Just to clarify I made a cut&paste error in my previous post. I am NOT switching to GBP-988. I'm actually switching to Tempo 5606. It's a marine chromate primer designed for underwater use. Tempo says that a top coat is needed for full protection if you intend to paint metal parts and soak them in the ocean (like any primer except for the 2 part epoxy like AKZO), but for our application one or two light dust coats is all you need.

This stuff goes on ugly, but it offers awesome protection. For anything that's visible (like the cockpit) I intend to topcoat with some sort of rustoleam finish.

I considered the 988, and it will likely work just fine for all of this stuff, but it really doesn't perform as well as the ZC. And the ZC doesn't perform as well without a topcoat as 2 part epoxy. Frankly, though, they're ALL probably good enough for aircraft use (as is NO primer at all) so it's all just up what you feel like using.

All I know is I'm sick of etching, mixing and cleaning so I'm giving AKZO and AFS the 'ole heave ho. I'd rather be rivetting and flying.

Once again, this is just what *I* do, and I'm not suggesting anyone else do this so don't flame me