Dismasting Imminent

Aug 2, 2005
1,155
Pearson 33-2 & Typhoon 18 Seneca Lake
Thanks for the picture, Roger. That looks simple enough to do. :doh: I'll follow your procedure at our next rig adjustment.
 
Jul 21, 2013
43
Oday 25' tall rig warwick, RI
Also I a SS flat washer helps a lot also, keeps the cotter pin off the surface. A washer is "standard" in the auto world with cotter pins.
HRJ
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
A washer is "standard" in the auto world with cotter pins.
HRJ
True and also standard in most other clevis and cotter arrangements. I never thought of it before but they are seldom seen on standing rigging and now I'm wondering why. Most clevis pins that come with turnbuckles and toggles don't have enough length for a washer.

I think the difference is probably that the clevis and cotters in most other applications are subject to a lot of movement whereas standing rigging is under pretension and there isn't much pin rotation.
 
Jul 21, 2013
43
Oday 25' tall rig warwick, RI
I have found that a lot of SS washers are thin. And on my boat the rigging is on both sides of the Chain plate. So what I do is get a small Vise grip & lightly tighten the two sides together,put the washer on & then slip the cotter pin thru, bend & then release the vise grip. Using a VG allows you to use both hands for the pin .But as you know any tool near the edge with fall into the water!!lol
PS I never use the rotating pin. I always use cotter. .And I usually put the vise grip on the head side of the pin to keep it from rotating as I try to bend the cotter pin .
HRJ
 

JST123

.
Jun 17, 2011
42
Hunter 33.5 Lake Ouachita
Sorry to disgree with you cotter pin installation roger :) but having worked in aviation my whole life we use the following per AC 43.13-1B 9/8/98
Page 7-26 Par 7-127​
7-127. SECURING WITH COTTER
PINS.
a. Cotter pins​
are used to secure such
items as bolts, screws, pins, and shafts. Their
use is favored because they can be removed
and installed quickly. The diameter of the
cotter pins selected for any application should
be the largest size that will fit consistent with
the diameter of the cotter pin hole and/or the
slots in the nut. Cotter pins should not be reused
on aircraft.

b. To prevent injury​
during and after pin
installation, the end of the cotter pin can be
rolled and tucked.

NOTE: In using the method of cotter
pin safetying, as shown in figures 7-6
and 7-7, ensure the prong, bent over
the bolt, is seated firmly against the
bolt shank, and does not exceed bolt
diameter. Also, when the prong is
bent over the nut, ensure the bent
prong is down and firmly flat against
the nut and does not contact the surface​
of the washer.
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
Sorry to disgree with you cotter pin installation roger :) but having worked in aviation my whole life we use the following per AC 43.13-1B 9/8/98
Well, I didn’t work in aviation my whole life but I was a private pilot and Maintenance Officer both of a flying club and in the Civil Air Patrol. I wasn’t an AP (aviation mechanic) so I didn’t install any cotter pins but, if I had, I would have done exactly as you quote. Why? Because the FAA says so.

Not everything the FAA tells you to do on an aircraft makes perfect sense but I have no quibble with their cotter pin standards. Why would I do it differently on an aircraft than on a boat? The cotter pins in aircraft are not subject to the corrosive effects of salt water so the changes in the metal due to the sharp bend are not very significant. On an aircraft, you do not, (or sure better hope you do not) have things like lines flailing around that can snag the ends of the cotters.

The part about the using the largest cotter that will fit the hole is correct for both plans and boats. That’s why the pins need to be cut short and filed smooth on a boat. Standard pins are simply too long. The only part of the cotter that is effective in keeping the cotter from backing out is the part just past where the bends make it larger than the hole. Anything much longer than required to create the bend just increase the chances of a snag and the leverage of the snagging line or object on the cotter legs.

If you try to drive one of these short cotters out, you will see that they are quite secure. Even driven into the hole, the spring in the ends will hold them hard enough that they will be tough to pull the rest of the way by the head. Pinching the legs back together still leaves them hard to remove.