Using Proseal

[alpinelakespilot2000]

All of my emp. parts are done with the exception of anything that needed prosealing (e.g. trailing edges and trib tab foam blocks). Having never used proseal before, I just wanted to check re: the following:

1. For cleaning trailing edge parts prior to closing, should I clean with MEK or lacquer thinner, or is something else necessary?

2. I'm attaching my trailing edges to aluminum angle while the proseal cures--should I insert and remove the clecos numerous times, clean them (with MEK?) each time until I think they are remaining proseal free?

3. Does proseal require a use of a respirator mask? I have one, but was hoping my wife could help me (I'm trying to do all emp. trailing edges in one batch). Do I need to get a second respirator? (The label instructions on my 3.5 oz tube of proseal say nothing about how to use it--or what its dangers are).

4. Once the proseal is in, and the edges clecoed together with the aluminum angle attached, is it OK to just take the weight off the control surface and move it around (and move on to the next control surface) or should I leave everything weighted down in the same place until the proseal cures?

5. How long is long enough for the curing process?

Thanks,

Steve

[PJSeipel]

1) I used MEK, because that's what Van's recommends. Use a respirator when you use MEK; it does a number on your lungs if you don't. Ask me how I know.

2) I did this on my empennage surfaces. It was a pain, but you finish with cleaner clecos and don't have to clean the holes out as much when you're done. I didn't do it on my flaps/ailerons and so had to spend time picking dried proseal off the clecos and out of the holes. Pick your poison. If I had to do it again I'd go with the 2nd method.

3) I would read the MSDS to be sure. I used it when I was doing a lot of prosealing because I was using a lot of MEK. The proseal does smell bad.

4) Leave the weight on. I would do your prosealing wherever is convenient, find a final location, put it there, and leave it there with the weight on for...

5) ...a week, if not two. Depending on heat/humidity of your chosen location. My garage in the winter took several weeks. If it sticks to your fingers it's not done yet.

(your mileage may vary, and I'm sure you'll hear from some of the people who advocate skipping the proseal and just riveting it.)

PJ
RV-10 40032

[jamiller]

Ask your mom, or grandma if she has any of that paraffin that used to be used to seal jam jars. Melt it, but don't get it too hot. Just before you stick the cleco in the hole, squeeze the pliers (to compress the spring and get the blade all the way out) and dip the end of the cleco in the warm wax. When the proseal sets up it, and the wax, chips off the cleco really easy. No MEK required!

Don't know if this tecnique is a good idea when doing the tanks (where you can't afford even the tiniest leak), but it works great for all other places. Works even better on epoxy.

Hope this helps.

John Miller

[Rick6a]

1. For cleaning trailing edge parts prior to closing, should I clean with MEK or lacquer thinner, or is something else necessary?

2. I'm attaching my trailing edges to aluminum angle while the proseal cures--should I insert and remove the clecos numerous times, clean them (with MEK?) each time until I think they are remaining proseal free?

3. Does proseal require a use of a respirator mask? I have one, but was hoping my wife could help me (I'm trying to do all emp. trailing edges in one batch). Do I need to get a second respirator? (The label instructions on my 3.5 oz tube of proseal say nothing about how to use it--or what its dangers are).

4. Once the proseal is in, and the edges clecoed together with the aluminum angle attached, is it OK to just take the weight off the control surface and move it around (and move on to the next control surface) or should I leave everything weighted down in the same place until the proseal cures?

5. How long is long enough for the curing process?

Thanks,

Steve[/quote]
I suppose as a production worker on the F-18 in which prosealing was a daily way of life, I do not view proseal with any trepidation whatsoever. Almost every component on that aircraft is (fay) sealed prior to riveting. You do not need a respirator (unless you cannot deal with a smell similiar to rotten eggs) except when using MEK or other solvents to clean parts because the cleaner the surface to be sealed, the more tenacious the holding power of proseal. I do not bother to clean cleco buttons and a little proseal buildup on them on them actually aids in holding the buttons in some holes. In the production environment, the buildup of proseal on clecoes that were used repeatedly did, over a period of time make inserting them more difficult and occasionally some clecos were cleaned by placing a batch of them in french fry-like baskets and dipped into an industrial strength ultrasonic machine for 20-30 minutes. Made em look almost like new. Don't worry though, your clecos will never get a buildup of sealer that bad. Anyway, one technique I always used at work and used quite successfully with my RV fuel tanks was to proseal the components and then 100% cleco the parts together. Then the next day I would remove the clecos as required to insert and shoot the rivets. Much less messier that way. One note: don't forget to dab a bit of proseal on the countersink before inserting the rivets in the fuel tanks. Helps to keep it fuel tight. Cure times can vary widely depending upon temperature and the type of mix. To keep things moving along, production foremen would often insist on heat lamps placed near curing proseal to speed up the process. For our purposes, that is not necessary. Depending upon the mix i.e.: A1/2, A4, B1/2, B2, B4, tack time can be as short as several hours with a heat lamp to several days depending upon ....temperature. Hope this bit of information helps.

Rick Galati RV-6A "Darla"

[N941WR]

Trick #1: When putting your cleco's in (with or w/o wax, great idea BTW!), stager them so they don't all go in on the same side. If you don't do this, the clecos will put a curve in your rudder.

Trick #2: Set the rivets by squeezing them with a pair of modified rivet sets. Check out the aileron page of my web site for pictures. Much safer and easier than back riveting them.

Good luck!

[txaviator]

Am I reading correctly, that you just shot the rivets in the trailing edge of the rudder, w/o any pro-seal or epoxy @ all?

I am getting to that point rather quickly, and I am searching for tips before I get there in construction.

Thanks.

[alpinelakespilot2000]

Bill-

Without using angle aluminum, how do you get the clecos to hold the trailing edge together tightly? I've found that the clecos can't grab the dimpled skin very securely when the cleco tip is trying to grab the female side of a dimple. However, they do hold the skin together tightly if clecoed into the angle where the tip does have something to grab. Thus, while I see merit in your suggestion, it seems like I can really only cleco from one direction (the from the side opposite the angle) if I want the cleco to really grab.

Thanks,

Steve

[dan]

I'm not speaking from experience with that trailing edge stuff (I built a folded rudder), but you might try wing-nut clecos. They are theoretically able to clamp tighter than spring-loaded clecos.

FWIW, I bought some #40 and #30 wing-nut clecos for use on my -7 here and there, and the #40 ones seemed shy diameter-wise...so your mileage definitely may vary.

Borrow one or two first, then if it works, order up a slew.

Hope this helps,
)_( Dan
RV-7 N714D
http://www.rvproject.com