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Posted: Mon Feb 21, 2005 5:26 pm
by MGVWfan
Beach, eh? I had one in my garage for a while after I finished up, it was gnarly, dude! I was tempted to kick back with my huarache sandals and listen to some surf music. :shock:

The orifice I referred to is in the air pressure path in the gun, it doesn't handle the media, so it will last indefinitely. The ceramic nozzle at the end does handle the media, is cheap, and available from Sears, and should last 10 hours or so of continuous use. 8)

No pitting, but I did notice a slightly rougher finish than wire brushing, and it left the metal kinda gray vice shiny. I followed the blasting up with a quick pass with the wire wheel, and it looks great now. :)

I swept the media up and sucked it up in my (clean inside) shop vac, and dumped the shop vac bin into the blaster's hopper twice during the evening. The blaster's got a sieve on top, and I didn't have any trouble with old paint, dirt, etc. clogging it up. A sheet of poly dropcloth, or a plastic tarp would have made the job easier.

I started with 50# of grit, and ended up with 25#. Guess where the other 25# went? :roll:

Of course, there was media EVERYWHERE, up in the fenders, on top of the engine hanger bar, etc., so I took today off and cleaned the car and garage up, wire brushed one last time, went over the engine bay with 320 grit paper, cleaned, cleaned, and CLEANED AGAIN, then applied ultra black RTV sealant on the seams. Now THAT was a nightmare, getting it to spead out and lay flat. It looks nasty, but the seams are sealed and I won't have to worry about water getting in the engine bay now.

I masked off the holes in the engine bay, and shot the first coat of (rattle-can) Self-Etching primer over the places that didn't have RTV (gotta wait 24 hours for it to finish outgassing before painting over it), and I'm waiting until tomorrow to finish priming. After a day for the primer to harden a bit, I'll sand the primer (I have a run or two in the primer :x ), clean again, and paint (unless the relative humidity creeps back up over 50%).

Posted: Wed Feb 23, 2005 5:18 pm
by MGVWfan
Well, the engine compartment is now primed!

http://www.thesamba.com/vw/forum/album_ ... _id=193951

:D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D

Posted: Wed Feb 23, 2005 6:06 pm
by DeathBus
SWEET SWEET SWEET!!!!!! Cant wait to see the finished results!

Posted: Wed Feb 23, 2005 6:31 pm
by MGVWfan
Me too!

Now I'm torn. Do I wet-sand to get it smooooth, or just go on and topcoat tomorrow night? I'm leaning to finishing it off, since it's just the engine bay...

Posted: Wed Feb 23, 2005 6:33 pm
by DeathBus
WET SAND!!!!!!!!! make it smooth, the oil will wipe off so easy.

Thx for the post!

Posted: Wed Feb 23, 2005 10:25 pm
by vwbill
Wow that's looking great!! So is that the self eching primer. Is it a greenish yellow color or just the flash doing that? Looks great!!
Your Bay is gonna be sweet and you did it yourself and that way you know how the job was done!! No hidden quick fixes! bill

Posted: Sat Feb 26, 2005 7:54 pm
by MGVWfan
Well, the engine compartment is now painted in New Ford Gray engine paint! :D :D :D Photos to follow.

Posted: Sat Feb 26, 2005 9:19 pm
by MGVWfan
Oh yeah, VWBILL, the primer was Dupli-Color Self-Etching Primer in rattle cans, and it is green. It's apparently a form of chromate primer. I've used it before with great results. Thanks for the complements! :D

Primer ?

Posted: Sat Feb 26, 2005 11:12 pm
by vwbill
Hey Guys, sorry to be ignorant but what is meant by self eching? I was watching that hot rod build show and they primed the body with a epoxy black primer before paint? So what would you use on the engine tins or cooling fan schroud or intake tube or block? I just used one of the engine gray case paints and engine enamel. Has anyone ever had engine parts powered coated? Is that better since its baked or do you think that happens anyway with the engine heat? Sorry to get off the subject of the sweet job you're doing! Thanks for the updates! bill

Re: Primer ?

Posted: Sun Feb 27, 2005 3:39 am
by DeathBus
vwbill wrote:Hey Guys, sorry to be ignorant but what is meant by self eching? I was watching that hot rod build show and they primed the body with a epoxy black primer before paint? So what would you use on the engine tins or cooling fan schroud or intake tube or block? I just used one of the engine gray case paints and engine enamel. Has anyone ever had engine parts powered coated? Is that better since its baked or do you think that happens anyway with the engine heat? Sorry to get off the subject of the sweet job you're doing! Thanks for the updates! bill
NEVER paint your engine!!!!!!!!! NO NO NO!!!!!! The air cooled engine depends on even the block itself to disipate heat. By painting the block you can raise your engine temps by 25 degrees!!! The paint acts like a blanket around the block holding heat IN. The best thing to do to your engine is have the case super cleaned in a parts washer with agents that dont harm aluminum.

Posted: Sun Feb 27, 2005 11:22 am
by MGVWfan
So what would you use on the engine tins or cooling fan schroud or intake tube or block?
I think VWBill meant the intake air distributor "block", not the engine block (right?). Yeah, it's not a real good idea to paint any of the engine (case half, cylinder barrels, heads), it interferes with proper heat transfer. I once painted an air cooled Briggs engine bright blue all over, and that engine never worked right after I did it. It ran hot and misbehaved.

The valve covers and everything else can be painted, and should be for rust prevention.

This is an interesting subject for me, since I've been doing lots of surface prep and painting of engine bits over the past 2 months. First, surface prep is critical. Clean the bits with detergent and water to get the dirt off, then paint thinner to get the grease off. Next, remove the old paint and rust. Rotary wire brushing and sandblasting work for me. Then clean with paint thinner AGAIN. Sometimes I follow up with MEK or acetone if I'm going to paint quickly (MEK and acetone evaporate quickly and remove all traces of paint thinner and grease). Carb cleaner spray also works well for small parts. Sand any spots smooth that are rough, if you want a smooth finish. Clean again with whatever solvent you're using. Let the part dry well, you don't want to trap solvent under the paint.

I've gone straight to topcoating from here and had it work OK, it just depends on the part. For example, I would always prime aluminium with self-etching primer, or some specific aluminium primer, to maximize adhesion. For small steel parts, I usually topcoat with 2-3 THIN coats of engine enamel, let them dry for an hour or so, then bake at 200 deg F in the kitchen oven (wait until the Base Commander's out to do this :) ). Baking really hardens the paint film nicely, it's especially good for valve covers and other engine bits.

For engine tin, I'm going to prime with self-etching primer, then topcoat with 2-3 THIN coats, then let dry for an hour, then bake (if they'll fit in the oven).

To get best adhesion to bare metal, some form of surface conditioning is required, along with priming. Usually, you should condition the metal surface by etching and converting any remaining rust in the pores with what Ray's mentioned before (he uses muriatic acid as a rust dissolver, and phosphoric acid as a converter), or other products sold specifically for auto body use.

This self-etching primer combines the conversion, etching, and priming functions into one product, and so far I've not had any coating failures. I'm going to keep using it where I can, and see how it holds up on engine bits.

I haven't used muriatic acid or phosphoric acid in the engine bay since I really can't flush the acid away without causing grief in the garage (the car's up on jackstands in the garage right now), and with all the crevices in the engine bay, I'm not comfortable with using a sponge to flush the acid away.

Posted: Tue Mar 01, 2005 7:24 pm
by MGVWfan
Engine bay pics on the Samba Gallery! :D

Posted: Wed Mar 02, 2005 5:32 am
by DeathBus
Image

Im glad I am not the only one who has to fight shovels and brooms when I work on my vehicles! :shock:

LOOKS GREAT!

Posted: Wed Mar 02, 2005 2:08 pm
by MGVWfan
Sometimes laundry too... :?

Thanks for the compliment.

Posted: Wed Mar 02, 2005 3:51 pm
by raygreenwood
Very nice. I had been contemplatiung painting my engine compartment, that medium gray similar to the color of the FI runners. Ray