Be advised if anyone uses the Taylor pneumatic rivet puller that Avery sells, they should not use the smallest tip on the puller even though it fits the rivet mandrels on the LP4-4 rivets.
I purchased the pneumatic puller after pulling only a few rivets by hand and realized I had 12,500 of these to do. The Taylor rivet puller that Avery Tools sells is good investment and makes the building experience fun not work.
When I recieved the puller I started using it right away. There were no instructions stating which tip to use so I used the tip that fit the rivet mandrels best. I immediately had problems getting the mandrels to release from the puller after the rivet was set. I called Bob Avery, as I heard he was very helpful on these matters. We tried adjustments to the internals and using silicone lubricant to no avail. Finally Bob sent me a new puller all set up and ready to use. When I recieved it I noticed it had the next larger tip on it. It has worked great ever since with only disassembly and lubrication on a few occasions. I use WD-40 as it seems to last longer than a silicone lube.
I met Bob at Sun-n'-Fun last year and thanked him for his help. We had never discussed the issue of using the right size tip on the puller, but it is important. The correct tip has a longer axial dimension than the smallest tip. This tends to push on and release the jaws from the mandrel when it cycles. The smallest tip does not and the jaws maintain a tight grip on the mandrel causing much frustration.
Now I'll get to the point. The correct tip has a loose fit on the mandrel. When you pull the rivet, sometimes a small amount of aluminum from the rivet head will migrate into this gap leaving a small burr and rarely the mandrel will break at the rivet head surface leaving a sharp point. This might lead you using the smaller tip, but as you can see from my experience, you will encounter bigger problems.
Rivet pullers from other manufacturers may not have an issue with the small tip, but the Taylor puller does. The aluminum burrs are easily removed with sand paper or a file. The mandrel burrs require a file or dremel tool. I have pulled over 12,000 rivets with the Taylor puller and it is still working great.
Art Pennanen