I don't intend to get in an argument with anyone here and I appreciate the sharing of knowledge and experience by everyone.
But, I need to point out the proper selection method for CherryMax rivets and my recommendation for adherence to the instructions in the Service Bulletins.
According to the CherryMax Process Manual CA-1015
, page 11, when using the CherryMax 269C3 Grip Gage, Step 4 says "Select the fastener with a grip equal to the next higher number. If the number reading is directly on a line you may use either that grip or the next higher one."
It does not call for the use of a shorter rivet when in-between marks on the gage. See their example #1.
Also, take note, when the Service Bulletin calls for a specific fastener (or an alternate), the use of those specific fasteners are the only approved method of compliance.
So in this case, when the Repair Doubler is used the only approved fasteners are AN470AD4-6 or the CherryMax CR3213-4-4.
My personal preference is, if I have the bottom skin opened up to install the Repair Doubler, I would choose solid rivets over the CherryMax rivets every time. I'm sure not everyone feels the same way.
The biggest mistake I see is not keeping the rivet puller totally perpendicular to the surface being riveted, this will almost always cause premature breakage of the stem, resulting in an improperly set rivet. CherryMax rivets do not tolerate any misalignment when setting the rivet. Be very aware of this if your rivet puller has interference with the part being riveted.
The CherryMax Process Manual has great information on the installation and removal of CherryMax rivets, so it should be required reading for everyone using them. KAI Section 5
also has extensive information on using CherryMax rivets.
Have a great weekend!