Priming 4 hours.
At this point, we had to decide to prime or not to prime. The same could be said for alodine/no alodine; lean of peak/rich of peak; Ford/Chevy; Red Sox/that marauding horde gang from New York. It is a bar room discussion the bartender prays won’t result in a visit from the local constabulary followed by a call to the insurance company.
The hard truth is, 6061 aluminum is already corrosion resistant, but there are arguments for extra protection. In our case, we are doing it because we can, and it is our first time, and being a learning process, we want to learn this Sling building thing really good. Plus, it would give us an excuse to wear the same sexy Tyvek coveralls that Naomi Campbell wears when she indulges in her own aviation pursuits.
That opened the next question. what sort of priming? We read through the blogs, noted that many were using rattle cans. That would be a problem. This project is dependent upon child/teen labor. Give a teen a case of rattle cans and Lord only knows how many fire hydrants, mailboxes and lawn ornaments might get tagged. It’s fastest way to ghettoize the neighborhood.
Another serious concern is the durability of the rattle can stuff. We looked at a few experiments done with the different primers, including rattle cans and 2-part epoxy, and the 2-part epoxy was more durable, and was less likely to flake off. There is no room in aviation for flakes.
Putting typical Aroostook County Siding on the SPDR
Working with the 2-part system wasn’t that bad, we mixed the 2-part epoxy in equal amounts, let sit a half hour and pour into the spray gun. Even with having to clean the spray gun dealing with the 2-part epoxy was easy compared to dealing with the cancerous nasty Alodine solutions.
There is one downside. In terms of not good times to be had, cleaning spray guns after every session stops just short of cleaning the fryolator at McDonald’s on cleaning jobs kids have to do. So, we made sure we had everything CRM organized to minimize the spray sessions, all the parts in trays, paint ready. We rolled SPDR onto a sheet of polyethylene and turned it into a ghetto grade paint booth by wrapping 3 sides in Polyethylene sheeting, which works well as a popular siding option in Northern Maine (tar paper being a very close second).
When it comes right down to it, spray painting is spray painting, whether tagging or rust proofing. Either way, it goes pretty fast, even if the police aren’t lurking around the corner. We sprayed the small parts first, tray by tray, starting with one in the bottom slot of the SPDR, and adding the trays into the SPDR as we went. After the small parts were done, we pulled out all the trays, hung the spars in the SPDR, and sprayed them. Once those were done, we put them back in the Bags and finally painted the skins as they hung in the SPDR. in short order we had all the frame parts done. We could rejoice that this part of the prep work drudgery was complete and we had parts ready for assembly, all without our neighbors’ houses, mailboxes and cars tagged.
Next: The Erector Set