| Author | Message | ||
| Devin Spears-Thomas (Thedewberries)
Rating: N/A |
Hi all and thanks for all of the old posts which helped with putting these materials together. I am going to skin individual windows on our MC9 with .090 5052 Aluminum. I will be using Sikaflex 252 and 3/16 aluminium monobolts to mount the panels to the bus. I know this is "double duty" but I like to overbuild. I will also be prepping and spraying each (7) panel with the Napa Green Zinc Chromate primer. The napaguy said that i should pre prep the aluminum with laquer thinner before it gets sprayed with the primer. yes/no? Should I spray both sides or just the outside? Being small panels do I have to heat/stretch the panels or just put them on? I will also be dipping the rivets in the green goo to avoid the corrosion problem. Anything You all think I should change or add to this plan, your info would be greatly appreciated. | ||
| Dale Waller (Happycampersrus)
Rating: N/A |
Devin, I was taught to scotch brite the aluminum before you wipe it down with thinner. Dale | ||
| Ed (Ednj)
Rating: N/A |
The napaguy said that i should pre prep the aluminum with laquer thinner before it gets sprayed with the primer. yes/no? > The metal will come with a protective layer oF oil on it. Thats why they say to clean it with Laquer. Clean it with what ever to remove the oil before primer, | ||
| jerry r breeden (Jerry_breeden)
Rating: N/A |
Devin, It would be good to sand first with 320 grit on a power sander of some sort. Also NAPA has a product called Twin Etch #6879 wich is a very good product from my experiance. I painted a custom aluminum boat using Martin senour products and the boats paint has held up very well. The etch primers they have adhere very well! For more info and product data sheets go to www.martinsenour-autopaint.com . Also PPG has Del-fleet which is their commercial line of paint. Prices are comparable .Prep well its worth the effort | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
Devin, I would try some Sikaflex all by itself before you go doing the double duty with the monobolts. The stuff is amazing and it's definitely not necessary to bolt or rivet as well. This eliminates the electrolysis problem too... I guarantee you if you prep it correctly it'll be permanent all by itself. I've done an entire trailer with some hairy tensioned- bends and the sika holds fast. I'm now doing my Bluebird with the stuff. No fasteners anwhere. Just be sure you sand to bare metal where you put the Sika primer, and wipe after sanding with isopropyl alcohol to insure grease free, then prime it. And don't forget spacers of some sort to maintain a bond thickness of between 1/16 and 1/8 inch. Last, why the 5052? If you're not going to bend it I might think of a stiffer alloy instead of soft 5052... But if you're going to be bending it, it's the right stuff to use. Cheers | ||
| Steve Padgett
Rating: N/A |
Devin, Steve from Sika here. Boogiethecat gives some good advice. Try the 252 without rivets. Bond some scrap together. Wait about a week for full cure and try a few mythbusters type experiments to tear it apart. You'll probably destroy the aluminum. Be sure to wipe the surface first with a clean cloth and Sika Cleaner 226. it dry 10 minutes. Use spacers to assure the 252 depth is about 1/8" | ||
| Marc Bourget Rating: N/A |
Gary, My thoughts (originally) on the 5052. But, IIRC, Bob Sheaves told me 5052 is what they used for aluminum armorplate at GM Military Vehicle Operations. I used "O" temper when welding up the fuel tank for the airplane project, but apparently some tempers are pretty tough! | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
I used 2024-T3 on my trailer, very stiff and not bendable. I personally would never use 5052 'cause it's so soft that if you whack it, it'll dent easier and the dent will stay. 2024 is a lot more resiliant before it will take a dent. My guesses as to why the military uses 5052 for armor are- (1) the designer is an idiot.. it happens you know.. but more likely (2) softer material will tend to squish under the influence of flying bullets or shrapnel, but may simply deform a bit and spread the energy of impact out whereas a stiffer material may fracture and let the nasties through a lot more readily. Often harder is not better, unless you're asking a woman..  | ||
| Bill Baxter (Willum)
Rating: N/A |
Devin, I would like to know why you are only doing 1 window at a time instead of doing 2 or 3 with 1 piece of aluminum and not have to deal with a seam? And also irregardless of the 1 window or more, I would think the aluminum should be heat-stretched. I may be wrong but that is just my idea, as I am going to be dealing with this real soon, as I have a 102A3. Good luck on your project whichever way you go. Bill | ||
| Marc Bourget Rating: N/A |
Heat stretching a panel attached with Sikaflex will "give up" the advantage of stretching right away. It's a plastic "property" of adhesives. It takes awhile for the stresses to "work out" the stretch - see Dave Galey's Bible for a discussion of the latter point. |