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USMC Herc

LSP_Members
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About USMC Herc

  • Rank
    LSP Junkie

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  • Gender
    Male
  • Location
    Eastern NC, USMC Central, Cherry Point
  • Interests
    WW2 Fighters n Bombers,Vietnam Jets to the current hot Rods flown. Usually build USMC Aircraft. I also love resetting the circuit breakers on beautiful women.
    USMC KC-130 Maintainer 6016 94-98. Delivered 45 KC-130Js to 252,352,152 from 2002-2010 with LM.

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  1. Peter I take some time off and this Mustang has her Fuselage covered. Your covering this beautiful girl so fast. She will be ready to fly by the end of the year. Keep making our jaws drop and enjoy the bruises as we read your post. Jason
  2. For WW2 aircraft I have no idea about removing manufacturer markings on aluminium in the field. When working civilian aircraft we would remove the markings. Don't want the customer to think I did a $h!ty Job. On USMC C-130s we scuffed for alodine and paint. Unless we where away from home and then we would let it ride. Story: While deployed we took a fruit bat (basically a dachshund with wings) through the leading edge of the wing making a soccer ball sized hole with feet sticking out of it. We where inspecting the damage when the Captain asked" how bad is it?". Which I replied "Don't worry Sir it will buff out." As he walked away, we maintainers started laughing. We chunked the bat in the trash and started our repair. We made the leading edge repair from Aluminium and tons of rivets. No paint or nothing on this panel, hung on a wing of a big huge C-130 painted in grey. You could see the repair from a mile away.
  3. Acid Etching / Metal Conditioning to Paint Aluminium Introduction Before primer and paint will adhere properly to a metal surface, it must be etched. Etching is a process that removes oxidation and microscopically roughens the surface. The accepted practice is to use a phosphoric acid etch. However, many commercial process use an alkaline etch on aluminum then follow up with an acid etch to de-smut the surface. The risk of using an alkaline etch is that the alkaline salts will be left behind causing corrosion sites to develop. In any case, the goal is to remove oxidation and roughen the surface. Another conditioning step is often done on aircraft aluminum. This step is a chromate conversion coating often called Alodine, although this is a trade name. The conversion coating helps protect the aluminum from corrosion in the field, and it also helps with paint adhesion. Etching Acid etching is a fairly simple process. For aircraft aluminum, phosphoric acid is the normal chemical used. Phosphoric acid is fairly safe in the concentrations used for etching, although if any gets on your skin it will burn and should be rinsed off. By the way, phosphoric acid is what give Coke and Pepsi their acidic taste or bite. You can purchase acid etch from various sources including Aircraft Spruce (Alumiprep), welding supply stores, and Home Depot and Lowes (a Jasco product that looks green). However, it is recommended to avoid the stuff from Jasco. It will work, but it does not list any surfactants in the ingredients list. Alumiprep and the stuff from welding supply stores contain surfactants, usually ethylene glycol and phosphates (typical ingredient in laundry detergent, at least it was typical). The surfactants are important to emulsify any remaining oil, dirt, and metal removed during etching process. Although you can buy acid etch off-the-shelf, for doing an entire airplane you may need larger quantities. Local chemical supply stores will often sell you what you need - 75% phosphoric acid and ethylene glycol. Sometimes the minimum quantity is 5 gallons, which may be in excess of $300. Sell the left over (a lot) to your local aircraft mechanics. Alumiprep and other off-the-shelf etching compounds will also contain hydroflouric acid. While this will also act to etch aluminum, its probable main use is to act as a brightener. Because this acid is not as safe as phosphoric acid, if making your own brew it is not recommended you purchase this. The phosphoric acid and ethylene glycol will do just fine. Mix one part acid, one part glycol, and one part distilled water for a 30% etch solution. Add 2.3 parts water to 1 part 30% solution for a 10% solution. Alumiprep ships at 30%, and sometimes you may want 30% for the really tough stuff. 10% is sufficient for most work. Don't try to etch everything at once. Pick a relatively small area and work that to completion. Spray or sponge on the etch, and lightly scrub with fine (green) or very fine (grey) Scotch Brite. It will take a little practice to realize when enough is enough, but the real test is when you rinse the etch off. The water should form a break-free surface if the metal is etched properly. Because acid is consumed during the etching, you will need to spray additional etch on occasionally as you scrub the surface. Because etching exposes fresh aluminum with lots of microscopic surface area that is easily oxidized, it is best to immediately follow up with the next conditioning process. Aluminum Conversion Coating All aluminum parts should be conversion coated for corrosion protection and good paint adhesion. The traditional conversion coat for aluminum is Alodine. Alodine is really just chromic acid. In powder form, it is an oxidizer and needs to be handled and stored carefully. Chromic acid uses the hexavalent form of chromium, which is known to be carcinogenic. For this reason, safer trivalent forms have been developed. One such product is Aluminescent. This supposedly a drop-in replacement for Alodine and meets the same milspec. However, it is quite finicky. pH must be kept within a certain range using potassium hydroxide and sulfuric acid (both are nasty) and a supply of pH indicating strips, the temperature must be above 70F, and it is difficult to tell if the conversion coat has been formed since it is a clear, although iridescent, coating. The color of the iridescence depends on the alloy of aluminum. While this may be Ok in a controlled production environment, this simply is too much for a shop environment. For these reasons, many users that have tried Aluminescent have switched back to Alodine. Alodine comes in either a liquid or powder form. For an entire airplane, buy the powder. You can mix it as strong as you like. Alodine can be sprayed, brushed, or sponged onto large surfaces. The surface must remain wet for several minutes or until a light to dark golden brown develops. Alodine should not be allowed to dry on the surface because of the salts it contains. If this happens, the surface should be re-wet with Alodine. Smaller pieces that can be immersed into a plastic tub of Alodine often take less time. After the conversion process is complete, the part needs to be thoroughly rinsed with water. It is often recommend that the parts be primed within 3 days of the conversion coating. However, the reason for this is uncertain. Information from Bondline.ORG
  4. Exactly this.......Where do you get a Sprue Brothers Coupon? Want to order a decal sheet but shipping is almost $9 here in the states. Help would be appreciated. Jason
  5. In this picture the cover is saying the aluminum Is treated with Alclad and type is 24S-T. The 24S-T may be the Manufactures number for this sheet of aluminum. In the Picture below the Aluminum Manufacturer is Reynolds Aluminum and it .O51 thick sheet. When I did sheet metal work we usually just used a green scotchbrite to remove these markings.. Jason
  6. I would love to see the "BEAST" in person. The pics you show are wonderful but would like to see the beautiful work in person to take it all in.
  7. I love the Mr.Color lacquer paints. I agree with using the self leveling thinner. When I first started using MC I didn't thin them enough. I would shoot paint and get spider webs. Once you get use to these paints you will love them. Just use in a ventilated area. Jason
  8. John The pastel weathering should help a ton. When i worked on C-130s we replaced placards only when they became unreadable and if they where important. Some placards have basic info that you can remember without placards. It is always your choice my friend, you are seeing the cockpit first hand and we only get to look at pictures. Jason
  9. works great now Fabio....all pics accounted for
  10. outstanding job sir. i do believe the decals help bring a cockpit to life. Your cockpit has been weathered with chipped paint but the decal placards need to be weathered accordingly. Great Job Jason
  11. you cannot ask for any better than this...Beautiful.
  12. Some ideas for new deck crew interacting with moving aircraft. "Move towards me" "TAXI" "STOP" Hands are usually closed and together for stop. AS you can see during normal day operations are done without wands. Below are Aircraft Marshaling signals.(just remove wands for same commands) Jason
  13. Beautiful figures. Do you have a web page or site to order these awesome figures. jason
  14. Staff Sgt, I served at 252 from 94-98 I worked in Powerline shop. I was with LM from 2002-2010 I helped deliver all 45 Kc-130Js to all three active duty Squadrons. Staff Sgt me and you are friends on FB and have talked over messenger. Want to do a little trading sir? Jason
  15. Patch as Requested And Now time to find the decal set....... Jason
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