CherryMax HELP!

[24Golf]

Well... thought I would save some time on the right leading edge to spar attachment and use CherryMax fasteners instead of bucking those LE rib rivets. All went well with the rivets that were installed where the spar doubler is, but when I got to the thinner area I must have used rivets that were a little to long. After pulling "several" rivets, I realized that they could be wiggled a little by hand. I figured out that the CherryMax Rivets that I had used were a little to long and I needed to drill them out. This ain't easy! Since they have a steel stem inside, it is hard to get a drill centered on them and when you do they like to just spin around in the hole.

Any ideas about the best way to get these things out without damaging the main spar and drilling oblong holes in it??

Thanks in advance...
PAUL

PS... Beth was inside fixing my birthday dinner or this probably would not have happened - she pays more attention than I do most of the time!

 

[Jconard]

You must puch the mandrel out first, and then drill them. Use a pin punch and sharpen it a bit.

Punch the mandrel out...takes some force and a focused hit....then drill the remains.

 

[az_gila]

Manual

You must puch the mandrel out first, and then drill them. Use a pin punch and sharpen it a bit.

Punch the mandrel out...takes some force and a focused hit....then drill the remains.

Since the mandrel is locked at both ends, the punching part might be difficult.

Grinding/sanding the lock off one end might help.

This CherryMax Process Manual shows what is going on in the rivet. See page 25...

http://www.cherryaerospace.com/files/pdf/catalog/CA-1015.pdf

gil A

 

[24Golf]

THANKS

Thanks guys... this will be very helpfull I will try again tonight.

 

[24Golf]

Thanks Again... The punch worked good, we just had to take the wing off of the rack so we could get some leverage.

 

[WilburD2]

Cherrymax drilling pt 2

Once you got the stem out, you'll see the rivet spinning when you try to drill it. To get past this, tilt the drill a little bit and rotate in the opposite direction of the drill. The head will eventually fall off.

Be sure to use a bit slightly smaller than the hole.. ie: use a #32 bit for a #30hole