![]() |
So I initially had some trouble with my first back rivet set. It had a wider collar so it didn't fit well due to the bend of the flange on the stiffeners. As some have said before I guess you could grind down one side of the collar. I ended up buying a different set that had a thinner collar. I cant remember who it came from, either Cleaveland or Avery. With this set I was able to get the set in the correct position and keep it vertical while running the rivet gun. From one of your pictures it also looks like your backriveting plate isn't polished or something. At least one of the rivets shown has a rough head like it was driven onto an un-polished surface. I purchased a backrivet plate from Cleaveland and it seems to work.
|
how heavy is the plate
i use a piece of steel 7/8 inch thick by 4 inches by 10 inches with 3/4 inch wood around it for a table the gun has just a small flat set without any spring to hold the metal together i use my other hand with a finger on each side of the rivet pushing down
|
Replace and try again.
I have the Cleveland plate that is about 6x10 or something around that size. No, it's not polished. I guess that does leave a bit of dark stuff on the rivets, but that cleans off easily.
I've pretty much decided to ditch these skins and stiffeners and order new ones and try again. :( That will also give me a nice big chunk to practice on and figure out what I'm doing wrong, then try it. Also, might try the Avery riveter this time also. I hear a lot of good things about that one. I'm just not happy how this turned out, sure, it would probably fly fine, but it's just really not pretty at all. I figure that it will just take me a few days to get the stiffeners cut, drilled, dimpled and primed and ready to go again. |
WOW! what a surprise
I went to the builders school at Vans in 1996 and one of the things we were taught was back riveting. I bought a one piece back rivet set which is several inches long (its out at the hangar or I would measure it - 6 to 10 inches is a guess) with a crook in the shank with the recessed head from Avery or Van's and never experienced any problem at all. I always practiced with scrap metal at the start of EVERY rivet session to get the pressure and the technique to an acceptable quality level before starting on the real work. Working with the steel back rivet surface plate and the back rivet set was a lower risk process than the common rivet set and bucking bar because of the forced flatness of the outer skin surface and the manufactured rivet head. When Jeanine and I riveted on the aft upper fuselage skins I got in the fuselage and used the back rivet set and she held a bucking bar on the manufactured head of the rivet outside the fuselage.
One thing I was taught at the school is rivets that are too long tend to clench so if they clench an alarm should go off that the rivet is probably too long. AND, if a rivet is clinched you can often do more damage by trying to remove it than leaving the slightly undesirable looking shop head in place and moving on to the next one. A rivet cutter to modify rivet length before riveting works very well for me. Bob Axsom |
Quote:
|
Quote:
I had the same problem with practice pieces. The rivet call out in the plans (especially the older model RV-6 plans) is a guide. Once I switched to the shorter rivet, problem gone. And yes, they may appear a tad short with a rivet gauge but are structurally just as strong. I'd rather use them then clench the longer ones. |
Quote:
Tom |
polish
I polish anything that touches the manufactured head. Rivet sets and steel bucking bars and the back rivet plate are polished using 400 grit and oil on a steel plate so they are as flat and smooth as possible. It keeps from scratching even though I plan to paint. I also use book tape to protect the skin.
|
I just put in an order for new skins and stiffeners. $156 for the parts. Overall, that's not a bad price. I just tell myself - if this was for a Cessna, 't would cost a LOT more and I would have to hire an A&P to do this and pay the hourly wage.
I also put in an order for the Avery backrivet set for $30 since that seems to be a popular one from what I've read. Now to remove a few stiffeners and practice to get these things right this time! :p Again, thanks for all the tips and advice. I don't know how we ever built airplanes without the internet! Tom --------------- RV7A Renton, WA Vertical stab - done Horizontal stab - done Rudder - 90% Elevator - starting over! :D |
| All times are GMT -6. The time now is 05:13 AM. |