Squeezer smilies

[Captain Avgas]

Originally Posted by GPV

Thanks for the tips and responses everyone. I need to go practice.

To answer your questions, yes the die was definitely correct and the squeezer is pneumatic. And you don’t need any protective tape. I was probably just lining it up incorrectly and my holes may be off a bit too. A fair few of my rivets were crooked so it wouldn't surprise me. Gonna have to go practice. Will definitely try some tape to protect things next time too.

Do I need to do anything to repair these things like sand them out?

I can tell you without doubt how to do perfect pneumatic squeezed rivets...every time. And you don’t need any protective tape. Firstly you need to understand that a pneumatic squeezer is like an untrained dog....you take it out walking on a lead but it just wants to go where it wants to go. You need to take control. Firstly don’t try to squeeze the rivet in one trigger press....that’s why you have those smilies. Press the trigger in two operations. Firstly press the trigger just enough that the set closes on the rivet but does not squeeze it. Just practice this on a couple of test rivets first (you should never practice ANYTHING on your plane). As you lower the set onto the rivet in this first stage you will hear air escaping from the squeezer. After the set has closed on the rivet you can then make sure that the squeezer is properly square to the surface you are riveting ( ie. the squeezer and rivet are not leaning over). Then, and only then, do you press the trigger the whole way to finally set the rivet.

And finally, and most importantly, keep a firm grip and control of the squeezer when you do the final squeeze. The big mistake builders make with pneumatic squeezers is they just let them go wherever they want to go during the actual squeeze. Take control of the dog. Keep a firm grip on it. Make it go where YOU want it to go..... not where IT wants to go. People think that because it’s a power tool they can just pull the trigger and let it do it’s thing....but that’s exactly how you end up with those smilies.

To summarise. 1. Close the set onto the rivet without squeezing it. 2. Check your alignment (if the rivet is not at 90 degrees to the surface then adjust it at this stage). 3. Grip the body of the squeezer firmly and press the trigger all the way to set the rivet. Don’t let the squeezer and rivet lean over during the actual setting operation. Control the dog.

Have a practice with this method and report back to this thread.

[MJarreau]

Greg,

I had trouble handling the pneumatic squeezer. I go painfully slow, having to concentrate on holding the squeezer tightly in both hands with the part rigidly held in place with clamps.

Things WILL improve. Keep at it!

Best of luck!
Mike

[Dbro172]

Your first sentence is the key, the yoke needs to be square, perpendicular, parallel, etc. to the rivet/surface. Need to get the sight picture down; try moving your head and eyes away from the part to visually check the alignment before pulling the trigger, then once you have it down you can move in closer and bang out rivets faster in the same line. Reset your sight picture in every new scenario. The eye never lyes!

I love banging out rivets with the pneumatic squeezer. Ka tss, Ka tss, Ka tss, ka tss!

[dwmillsap]

+1 for black gorilla tape, never make another smiley again.

[GPV]

Thanks for the responses everyone! I'll go hold it tight and use the gorilla tape. I should be strong enough to hold the dog haha.

Does anyone have any thoughts regarding whether or not the smilies need to be removed by sanding, etc?

[dmn056]

Originally Posted by GPV

Thanks for the responses everyone! I'll go hold it tight and use the gorilla tape. I should be strong enough to hold the dog haha.

Does anyone have any thoughts regarding whether or not the smilies need to be removed by sanding, etc?

The various riveting specifications are fairly restrictive on damage to surfaces surrounding rivets. For example:

MIL-R-47196A - 4.2.1 Defect standard. Rivet installations showing evidence of the following defects shall be classed defective ... p. Cut or marred skin caused by careless use of a bucking bar or rivet set.

MIL-STD-403C - 5.4 Skin damage. Damage or deformation of the skin from the riveting equipment or flushhead shaver shall not be acceptable.

MIL-STD-40007 - 5.4.5 Marred surfaces. A cut or ring on the preformed head or the surrounding material caused by the riveting equipment shall be cause for rejection.

So, based on the specifications, if it's only the primer you're OK, if it's the metal that's damaged you may have a problem.

In spite of these specifications, Van's tends to be a bit more tolerant, probably because they know what the safety margins are in their designs. When I damaged a spar web adjacent to a rivet head they were happy for me to blend it out, and I know they have given similar advice to other people. Send them the picture and explain exactly where it is, and see if they recommend you to do anything.

Hope this helps

[GPV]

Thanks Dan, I'll run it by vans and see what they say. On a positive note I tried putting the job in a vice and using the squeezer with two hands. Talk about a difference! Rivets are now pretty much perfect, as can be seen here:

https://www.instagram.com/p/B3WrQU1h...=17k7g5khoxjzf

[Southern Pete]

The question to ask is what you would do if you sand the paint and find the metal is dented? There are really only 2 answers, do nothing or replace the part.

If you're content to live with it then don't sand the paint, just carry on.

If everything must be perfect then start drilling out rivets.

If there are only a couple of smileys then I would ignore it and continue. You will cause more damage to the structure by drilling out and replacing than by accepting this is a learning process.

Pete

[MJarreau]

There are really only 2 answers, do nothing or replace the part.

Pete, what is wrong with sanding / buffing out the smile? From image, the smiles do not appear significantly deep. Would that not be a 3rd reasonable possibility?

Thanks,
Mike

[Taltruda]

Another thing that may help... one guy mentioned to control the dog and go slow, closing the squeezer before setting the rivet. I agree with him but wanted to see if your squeezer is allowing this or does it just fire? I had a squeezer that you couldn?t go slow, it was on or off. And that means you need to send it out to be rebuilt. It should be able to move really slow and controlled. Also do NOT oil the squeezer, it?ll wash out the grease internally and ruin the squeezer