It seems a lot of newbie aircraft builders have problems with their pneumatic rivet squeezers, as I did.

At first, you it can be hard to get the squeezer to squeeze rivets. You want to call the company that sold you your squeezer and tell them it is defective, but it’s NOT.

I found this article from Cleveland Tools which explains clearly how to setup a pneumatic rivet squeezer. Below is some of the information in the article. I would recommend reading the whole article.

  • First leave your compressor set at 90psi. This is true for all air tools except paint sprayers.
  • Take a look at the squeezer setup table at the bottom of this sheet. This table will showyou the mathematically derived gap setting for the squeezer for each different rivet size.

    This is only a good starting place due to internal compression and possible yoke flex.

  • To adjust the gap, use any combination of: different length flat and cup sets, shimwashers under the flat and/or cup sets, or by adjusting the adjustable ram if you have it. By gap I am talking about the distance between the two squeezer sets when the ram is fully extended with no material in between them.
  • Try to compress a rivet. One of three things will happen.

o Therivetwillnotbesetenough.(decreasethegapveryslightly).
o The rivet will be overset. (increase the gap very slightly)
o The squeezer will come up to the rivet and stop without squeezing it. This is

when we get the call. Here you need to increase the gap very slightly. I know this does not make sense, but do it and it will work.

Table Shows Mathematically Derived Gap Between Squeezer Sets for Various Rivet Sizes

-3 Rivet Length

-3.5 Rivet Length

-4 Rivet Length

-4.5 Rivet Length

-5 Rivet Length

-6 Rivet Length

-7 Rivet Length

3/32″ Diameter Rivet

3/32″

1/8″

5/32″

3/16″

7/32″

9/32″

11/32″

1/8″ Diameter Rivet

1/16″

3/32″

1/8″

5/32″

3/16″

1/4″

5/16″