Amphibious HEMTT

[WaterH]

I wouldn't dream of painting all that bare aluminum without laying down a light coat of etching primer first.
A good etching primer from an auto body supply shop, or Duplicolor in rattle-cans (my go-to) is worth it.
After that, even house paint should stick well (but wait a month so it's fully crosslinked & cured before clawing at it).

Is zinc cromate "etching". I thought it was the supposed to be the best for aluminum. I think they made it illegal in Canada, so I figured it must be good.

i will be looking into rapco. It's amazing how many pages of people have used the Behr with good results in SS. But if I'm not satisfied on a scrap piece, it's not going on my truck.

 

[reptillikus]

Id go to Rapco. You get what you pay for, and youve got some amazing work in this thing, hate to 'ruin' it with a bad paint job.

 

[ExWrench]

Is zinc cromate "etching". I thought it was the supposed to be the best for aluminum. I think they made it illegal in Canada, so I figured it must be good.

i will be looking into rapco. It's amazing how many pages of people have used the Behr with good results in SS. But if I'm not satisfied on a scrap piece, it's not going on my truck.

Real zinc chromate (the outright cancerous shit with hexavalent chromium in it, not any dolphin-safe "relacements") is a great corrosion preventative (1000+ hour salt spray) on wrought aluminum. It's seriously bad shit health-wise, so keep it off you, your family, and your animals. If you want a non-cancerous alternative, TCP (uses trivalent chromate instead of hexavalent) is as good on any Al alloy with less than 2% copper. I wouldn't bathe in TCP, but it doesn't guarantee the big "C" the way ZnCrO4 does.

Regardless of your conversion coating, it can be directly painted over if part of proper prep. A good ZnCrO4 primer over clean aluminum should be a winner. I'd let that test panel cure completely (at least 2 weeks unless you're baking it) and then do a tape test for adhesion.
Something like this (random link of short, basic rundown): https://swppc.com/2016/12/05/the-bes...aint-adhesion/
Note: only score through the coating to the substrate, don't gouge the metal.
If it passes that, you've got a proven system.

Paint is "dry" within a day or so, but is not fully cured until all the polymers get done cross-linking (function of time & temperature). You may have dicked the reaction slightly by over-thinning, but if it dried fine then likely not. Most likely, you just fucked with it before it was anywhere near cured. Fully cure it, do a tape test, and then you'll know. On such a unique rig you dreamed up & built by hand, be patient and prove out your coating process before finishing anything that would suck to strip & rework.

Shit, I'm almost rambling - hope some of that gives you good ideas.

Rig looks awesome - home stretch, brother! - be patient

 

[bdkw1]

Any aluminum we get painted gets chem-filmed first to make the paint stick. The Epoxy polymide high solid paints for the military stuff we had to send to AZ to get painted, Komifornia wouldn't allow the stuff to be sprayed or it was to big of a hassle and nobody wanted to deal with it.

 

[Bigblue 94]

Real zinc chromate (the outright cancerous shit with hexavalent chromium in it, not any dolphin-safe "relacements") is a great corrosion preventative (1000+ hour salt spray) on wrought aluminum. It's seriously bad shit health-wise, so keep it off you, your family, and your animals. If you want a non-cancerous alternative, TCP (uses trivalent chromate instead of hexavalent) is as good on any Al alloy with less than 2% copper. I wouldn't bathe in TCP, but it doesn't guarantee the big "C" the way ZnCrO4 does.

Regardless of your conversion coating, it can be directly painted over if part of proper prep. A good ZnCrO4 primer over clean aluminum should be a winner. I'd let that test panel cure completely (at least 2 weeks unless you're baking it) and then do a tape test for adhesion.
Something like this (random link of short, basic rundown): https://swppc.com/2016/12/05/the-bes...aint-adhesion/
Note: only score through the coating to the substrate, don't gouge the metal.
If it passes that, you've got a proven system.

Paint is "dry" within a day or so, but is not fully cured until all the polymers get done cross-linking (function of time & temperature). You may have dicked the reaction slightly by over-thinning, but if it dried fine then likely not. Most likely, you just fucked with it before it was anywhere near cured. Fully cure it, do a tape test, and then you'll know. On such a unique rig you dreamed up & built by hand, be patient and prove out your coating process before finishing anything that would suck to strip & rework.

Shit, I'm almost rambling - hope some of that gives you good ideas.

Rig looks awesome - home stretch, brother! - be patient

The big C and coatings aint no joke.

Every single "100% acrylic" colorants for our "green/eco friendly/low VOC paints says right on the label suspected of causing cancer.

Then theres the 844 series industrial colorant. After just a few minutes of olfactory exposure leads to nausea, headaches, and dizziness. Ive seen it knock my uncle out just tinting paint. With ventilation. This is the stuff used in epoxies.

 

[WaterH]

Small up date,

I didn't have a radiator overflow yet. I was going to buy or make a fancy aluminum one, but thinking on it, I figure the best choice is probably plastic. So I just ordered a generic one from Summit.

I mounted it under the engine cover. One more job off the list.

Edit, after posting this, I saw three posts about paint that I missed somehow. A lot of good info. Thanks guys. I'm not painting anything for a couple weeks. I painted another unseen part with full strength paint. Scotch brite, brake clean and zinc cromate first. This time I did it in the shade and the finish is nice. (Some texture, but not like sand paper)

 

[USMC Gunny]

Holy shit, this is amazing. I can't wait to just see more.

 

[WaterH]

Instead of house paint and all that, why not contact Rapco? it's where i got the paint for my jeep, they do period correct military paints back to WW2, the satin olive, the old OD green, vietnam era paints, the CARC paints but without whatever evil chemicals were in it, etc..and they're great people, call and they'll help you out all they can. They can even send a variety pack of spray cans so you can figure out what you like best.
http://www.rapcoparts.com/padenew.html

Edit, didn't see that rapco was mentioned right above my post lol

It would appear rapco is shut down for covid. They never answer the phone and don't respond to messages.

 

[Drummer79]

It would appear rapco is shut down for covid. They never answer the phone and don't respond to messages.

I'll ask my buddy who does military vehicle restoration who else he uses tomorrow. We were just talking about paint suppliers yesterday and he mentioned another place.

 

[Drummer79]

It would appear rapco is shut down for covid. They never answer the phone and don't respond to messages.

I had trouble getting anyone at Rapco on the phone last time I tried too, Might be worth continuing to try, but if not, https://store.midwestmilitary.com/Sy...les-s/1967.htm was recommended by my buddy Chris who's restored at least a dozen different era military vehicles.

 

[WaterH]

I had trouble getting anyone at Rapco on the phone last time I tried too, Might be worth continuing to try, but if not, https://store.midwestmilitary.com/Sy...les-s/1967.htm was recommended by my buddy Chris who's restored at least a dozen different era military vehicles.

Thankyou

 

[Drummer79]

Thankyou

Any time. Their prices are comparable to Rapco, I've never used them though. Chris says they're fine though so good enough for me. They have another page of a two part paint, more like modern era paints with a catalyst, but the prices are nuts on those. The link i sent is the paints more like I've sprayed before and Chris as well.

 

[WaterH]

Well my test piece is still not scratch resistant after more than two weeks. I finally got ahold of Rapco and ordered some paint from them. We'll see.

 

[DirtRoads]

Well my test piece is still not scratch resistant after more than two weeks. I finally got ahold of Rapco and ordered some paint from them. We'll see.

Without reading the entire thread, aviation wants you to coat bare aluminum with Alodine and then prime with Zinc Chromate for max corrosion protection. Depending on what type of sheetmetal you used, you might be able to skip the Alodine.

 

[WaterH]

Without reading the entire thread, aviation wants you to coat bare aluminum with Alodine and then prime with Zinc Chromate for max corrosion protection. Depending on what type of sheetmetal you used, you might be able to skip the Alodine.

Yea, I have Alodine, but if you don't do it exactly right, you have a bigger problem. I am using zinc Chromate and sticking to the aluminum is not the problem. It just seems the house paint takes to long to dry hard. (Or I got a bad batch) Based on my testing, I can't recommend Bahr for a house. Lol.

I'm using 6061-T6 aluminum. The only reservation I have with the rapco paint is it might be too flat. Some of the military guys said that a little shine makes it a lot easier to wash. I don't want gloss, but a satin would be nice. The guy at rapco told me I could mix some clear hardener in and it would have a little more shine. Of course, that means more testing.

The guy at rapco told me to buy a Harbor Frieght spray gun for $30. I went there and they had $16 and $129 guns. I got the $16 one. It looks OK, but can anything be good that cost $16?

 

[Flatbed]

I believe Doc rocked the fuck out of the cheap bastard with good results.

 

[Drummer79]

Yea, I have Alodine, but if you don't do it exactly right, you have a bigger problem. I am using zinc Chromate and sticking to the aluminum is not the problem. It just seems the house paint takes to long to dry hard. (Or I got a bad batch) Based on my testing, I can't recommend Bahr for a house. Lol.

I'm using 6061-T6 aluminum. The only reservation I have with the rapco paint is it might be too flat. Some of the military guys said that a little shine makes it a lot easier to wash. I don't want gloss, but a satin would be nice. The guy at rapco told me I could mix some clear hardener in and it would have a little more shine. Of course, that means more testing.

The guy at rapco told me to buy a Harbor Frieght spray gun for $30. I went there and they had $16 and $129 guns. I got the $16 one. It looks OK, but can anything be good that cost $16?

i went with a actual flat green, 319 I believe, but they have a kinda semi gloss version too. I had no issues washing anything off of the flat paint. It would kinda of take on a semi gloss in places where oils from your hands constantly touching contact it though, like around the door handles, but gave it character to me. I'll try to load a pic of my jeep painted with Rapco paint, but not sure i can. I painted the rocker guard with the semi gloss paint because I had ordered a can to test with. The rest is 319. This is right after painting and before putting flares and all back on and the new tires and all. Second pic is after it was finished.

 

[WaterH]

Drummer, that looks great. Has just a little sheen. The color I'm getting is 383, but it looks close to that. Maybe a little darker.

 

[WaterH]

OK, I just did some test spraying with the Rapco paint and the purple paint gun from HF. The results look fine, but it seem like I needed to paint the same spot several times to get it covered. I'm not thinning the paint at all. Is that the issue? I saw on utube, they drill out the tip to 5/64" to spray primer. Should I try that?

Pretty much all my spray experince is rattle cans. Any tips welcomed.

 

[bdkw1]

If it's feeding fine and laying a good layer down, no need to thin it.

 

[Drummer79]

OK, I just did some test spraying with the Rapco paint and the purple paint gun from HF. The results look fine, but it seem like I needed to paint the same spot several times to get it covered. I'm not thinning the paint at all. Is that the issue? I saw on utube, they drill out the tip to 5/64" to spray primer. Should I try that?

Pretty much all my spray experince is rattle cans. Any tips welcomed.

I painted my jeep with a 12 pack of rattle cans from Rapco, so i can't help you there. With the rattle cans it laid down beautifully on the sides of the jeep, but on the hood rattle cans don't spray as well pointed down like that, i wish i had removed the hood to get it to lay down smoother.

 

[WaterH]

The utube vid said the tip comes 1.4 mm. They say drill it to 5/64 which is 2mm. Then it should be good for primer or thick paint. I drilled it and will do another test spray tomarrow. If I "F"ed it up, I'll buy another gun. That's one good thing about a $16 gun. I can buy another instead of cleaning it.

The test piece today is more scratch resistant in two hours then the house paint is in two weeks.

 

[WaterH]

So here's my test piece up against the house paint. The color looks a little differnt. I like both of them, so that doesn't matter. I can definitely say this Rapco paint is allot more scratch resistant. I can just drag my fingernails on the Bahr paint and scratch it. I had to push my nails in this with maybe ten pounds force to make a mark. Even then, the scratch kind of rubs off.

On to another project, I got some water temp sensors for the radiator fans. I decided to install them in the stainless tubes I made previously to run water to the rad. I bought these stainless "bungs" to weld in. I know I could have made them, but I need to get this truck done in my lifetime.

i also got a bung for a water hose to connect to a air/water intercooler. I haven't decided if I will install the intercooler yet, but I can weld the bungs in and plug them. Then if I decide later, I can just put nipples on. I welded them on with the tig.

I welded them on with out a hole. Then I pressure tested them while spraying them with glass cleaner. (For bubbles.) Then drilled the holes. I welded these on with argon on the inside. This is a trick I learned when welding the fuel tank. It's kind of a pain because I have to have my spare argon tank hooked to plugs on the ends. It sure makes the welding go easier.

Installed back in the truck with sensors.

Here is the intercooler I got for this. I haven't worked out mounting it, but it shouldn't be hard if I decide to do it. I prefer not to make more failure points, but if the EGT's are too high, I might have to.

 

[WaterH]

Got a couple questions for you guys. I'm wiring fans up to a relay that will be fired by the thermostat switch. Should I run an inline maxi-fuse? If the answer is yes, should I place it between the bus bar and the relay or between the relay and the fan?

 

[WaterH]

So I've done a lot of work since my last up date, but not much to show.

Started body tear down for final riveting and paint.

While I was building, I kept running out of clecos. I had to keep buying more. By this time my cleco can is over flowing.

I can't believe how many parts I made.

Riveting the front floor. I zinc cromate the joints for some corrosion protection.

Bolted on the truck.

I made some rubber gaskets where the brace tubes go through the cab. They are solid mounted from frame to bumper. Since the cab is rubber mounted, I needed some flex right there. But I still didn't want water, heat or cold to leak there.

Here you can see it at the front.

Headlight section. The green is just zinc cromate, but it is close in color to the military "383" green I will be painting later.

I painted the bottom with Rustoliem bedliner. You can see some of it here on the backside of the footwell. I had the inside of the fenders coated with Rino liner. This stuff looks the same. I guess I could have saved myself a lot of money.

I should have some more up in a few days.

 

[Flatbed]

Good to see an update Pics of the Bug? Looks clean.

 

[WaterH]

Good to see an update Pics of the Bug? Looks clean.

Pretty much stock. Only thing I did to it was install disc brakes up front. (Wasn't really safe to drive with the drums) Bought it to install a wrap on for advertisin, but never got around to it. I should sell it, but it's cheap to keep and I don't have to work on it. It runs great and is clean inside and out. I get offers to sell everytime I take it out.

 

[bdkw1]

Nice update!

 

[WaterH]

Got some more work done. Not much to look at, but details take up the time.

Finished riveting the second level floor. (Where the seats mount) Painted the bottom with bedliner. Note the cup holders. I originally made some fancy slash cut cup holders that were flush in the raised section on the side. Got them all done when I realized I couldn't put them there because they would hit the fenders.

I had a perfectly good alternator, so of course I had to get another. And make new mounts. It is 210 amps vs 130 amps. It also has a tach wire. The main reason I got it.

I mounted another idler to wrap the alt better. The old one squealed on start up.

I started plumbing the airbags. I had just a shrader in them before. Now I have a line that threads on the shrader. That way, if I get a line leak, I can just unthread it and fill with a airchuck till I get it fixed.

I also plumbed in some air horns. These horns will wake the dead. Can't wait till some antefa guy starts yelling at me with a bull horn. Lol.

I got the console valves mounted. Powered up the compressor and played in the garage like a Mexican low rider. Lol. One problem came up. The gauges go from 0-60 psi. But the compressor is set to 110. (I think) when I switch the valve, the gauge pegs. It only reads the bag pressure after I let off the valve. Well, I guess the needle can't take being pegged and broke on one of them. If I only move the toggle alittle, it won't peg. Not sure if I'm going to have to change something here so some stupid doesn't break all the needles.

You can see the giant hole I put in the floor to run the AC and heater hoses. Not so giant now and I still have other shit to run through there.

I got some trick billet knobs on the bay for my heat and AC fans. I got one for the wipers also. Not pictured.

Thats all for now.

 

[Elwenil]

I'd be cutting out that crumple zone in the frame and replacing it with some tubing. You have a lot of weight hanging off the front of that frame and it was only supposed to support a bumper. Plus it just looks like shit, and I wouldn't trust Ford engineering for shit.