Like pushing teeth

Kermit

.
Jul 31, 2010
5,722
AquaCat 12.5 17342 Wateree Lake, SC
We sailed in a pretty stiff breeze today under main alone. On the way back in I noticed a pretty big wobble in the mast/boom connection. I dropped the main quickly and motored back to the dock. The pin that connects the boom to the mast had pulled partway out. We got it back in with a fair amount of difficulty. Lining up the holes was like pushing teeth!
I bought a new pin from West Marine on the way home. Are those two bitty little spring-loaded balls normally strong enough for the job? I can't help but think a ring ding on each end would be better. What say y'all?
image.jpeg
 
Nov 6, 2006
10,212
Hunter 34 Mandeville Louisiana
Yup.. or if ya not removing it a lot, a bolt and nylock nut. Here is the connection on the 34.
P1000700.JPG
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
I doubt that pin was original. A ring fitting would be much more secure.
 

Kermit

.
Jul 31, 2010
5,722
AquaCat 12.5 17342 Wateree Lake, SC
Thanks y'all. And Kloudie, I *really* appreciate you running down to your boat right quick to take that picture for me!
 
May 24, 2004
7,213
CC 30 South Florida
It looks like the joint between mast and boom lost stretch or compression forces allowing vibration to work the pin out. It could happen again so I would not rely on a spring loaded pin. Get a bolt and locknut.
 

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
8,020
Hunter 430 Waveland, MS
Get a bolt and locknut.
Looking closely at your picture, @Kermit , someone thought the same thing. At least someone recently scratched the circular area around the pin shaft.
Note @kloudie1 picture has simple snap ring on the lower pulley shaft. Both his and yours rely on the "spring" effect to secure the bolts, laterally.

The pin that connects the boom to the mast had pulled partway out
Although most of the mechanical forces are NOT lateral (left and right movement) they can "slip" out.
The weight of your boom prevented the bolt loss.

Put it this way...
I would sail, as crew, with you and your rig as shown. It should be ok as long as the itty bitty spring inside the bolt works for several seasons.
Jim...
 
Jan 22, 2008
296
Islander Freeport, 41 Ketch Longmont, CO
My H28 used pin and ring, one way to help a little is to put a washer on either side but, it is generally not necessary. Go with as big a ring as you can, fit on the pin and you'll be fine.

Do not use a bolt/nut setup, the boom moves up/down based upon vang, mainsheet and sail settings and the movement will eventually cause the nut to back off of the bolt.

Fair winds
 
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Likes: JamesG161
Apr 19, 2012
1,043
O'Day Daysailor 17 Nevis MN
Do not use a bolt/nut setup, the boom moves up/down based upon vang, mainsheet and sail settings and the movement will eventually cause the nut to back off of the bolt.

Fair winds
With the nylon locknut, as shown in the picture, you'll have no problems at all.
 

Kermit

.
Jul 31, 2010
5,722
AquaCat 12.5 17342 Wateree Lake, SC
Thanks to Joe Blizzard I decided to call Dwyer Mast. Here's the definitive answer. Part 6 is the pin they used with part 7 on the other end.
dh3100-1_linedrawing.jpg
 
Jun 11, 2011
1,243
Hunter 41 Lewes
On some masts the tolerance is so close when the boom is swung to one side that you must use a pin because the head on the bolt will be a problem. It's not good to have thread on moving parts as these and they use a pin because it is full shouldered. I'm glad you found the part. get two.
 

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
8,020
Hunter 430 Waveland, MS
Thanks to Joe Blizzard I decided to call Dwyer Mast. Here's the definitive answer. Part 6 is the pin they used with part 7 on the other end.
Hmmmmmm PART 9 looks familiar. You need up and down freedom and a lateral pin holding mechanism. I think your new part is good to go.
Jim...