fiberspar carbon boom - bend

alap · Joined: 17 Dec 2007 Posts: 156

Had great session, about to derig and notice that my boom is funny looking:

https://photos.app.goo.gl/zXcPk3rgh7fEBMcx6

It is 7.0 dedicated boom 170-218.
Set at 197 (middle)

bought it new around 2004, so roughly 20 hours a season, 300 hours total

yes it was overpowered session, and sail completely outhauled, but nothing exceptional.
What was unusual, there was a strong gust, I was completely in control on the reach, and then suddenly "boom" , noise like sail does when it backwinds.
Couple minutes later I see that the outhaul is not to the max , about an inch between sail clew and boom.
Weird, never happened before, but I thought may be it is adjustable sailworks outhaul cam lock gave a little....
Anyways, outhauled back to the max, sailed for half an hour, and then it died down a notch, so I let a bit of outhaul. Everything as usual.

so basically, Qs:
1. i thought that carbon is not bendable, it just breaks
2. is it safe to continue to use, or it will break pretty soon? (I don't care how it looks)

pmlct · Joined: 02 Mar 2010 Posts: 68 Location: Middletown CT

Did you take the tailpiece out of the body of the boom to examine properly? It looks broken from here, but my x-ray vision doesn't work that well from far away.

boardsurfr · Joined: 23 Aug 2001 Posts: 1266

manuel · Joined: 08 Oct 2007 Posts: 1158

It looks like the clip slipped. Those tabs wear out, break and skip. On an old Neilpryde boom I wrapped the tabs with electrical tape so that the clips are tighter when twisted shut.

Get the tail piece out and try to bend either part, see how they react.

swchandler · Joined: 08 Nov 1993 Posts: 10588

If you take the tail extension off, there is a strong likelihood that any partial break in the boom arm will show a lot of play at the compromised area.

I had an experience with a Gulftech Glory carbon boom where the carbon tube coming out of the front end cracked, but it was not visible. Yet, the boom didn't seem as stiff and stable overall. It was only after I removed the extension later after coming in that I could see just how bad things were. I account myself quite lucky that it didn't completely break apart while on the water. Needless to say, the boom was toast.

alap · Joined: 17 Dec 2007 Posts: 156

Update, added five pics to the end into this album: https://photos.google.com/share/AF1QipPltvxehkgk-WuhQDHFRh6lvchsyLcnYvpeVx7O5sWEatwyJ_wRuPP15V4LqJqERA?key=V1RwYkJMLXotQ0djWHd2bUJwM2lqXzUwc3FJZzl3

so the first thing I noticed today in the morning is that one arm is 4 cm shorter:

https://photos.google.com/share/AF1QipPltvxehkgk-WuhQDHFRh6lvchsyLcnYvpeVx7O5sWEatwyJ_wRuPP15V4LqJqERA/photo/AF1QipO-0TQoBbFd0toOpJJxutV3zzkW62ICLQcMveNw?key=V1RwYkJMLXotQ0djWHd2bUJwM2lqXzUwc3FJZzl3

strangely it is clearly visible on prev photos. I guess I was in a mild shock.

I immediately realised that Manuel was correct!

The locks were stuck but I have a tool (next photo)
I applied some force - boom, pop, kaboom and it all was straightened.
Tail piece slides smoothly,
boom looks normal. (two next pictures)
I guess carbon is allowed to bend under pressure, like in carbon mast.

Anyways, Manu Q to you.

Last picture in this album:
https://photos.google.com/share/AF1QipPltvxehkgk-WuhQDHFRh6lvchsyLcnYvpeVx7O5sWEatwyJ_wRuPP15V4LqJqERA/photo/AF1QipN1jXsAgVV7cZKAK9PmLGBTKqHV0iTLwmvolZld?key=V1RwYkJMLXotQ0djWHd2bUJwM2lqXzUwc3FJZzl3

To fix it I just position lock in the desired grove and then wrap one or two(?) layers of electrical tape around it, and then slide and turn the cover?

Not that you suggest to wrap tape around grove itself and put sliding locking mechanism on top of it?

manuel · Joined: 08 Oct 2007 Posts: 1158

Exactly. Did you notice the twist clips were pretty loose, easy to close with little resistance? They need to be somewhat firmly closed.

The grooves wear similarly to holes wearing from metal pin friction.

EDIT: the tape is there just to add some girth, the boom can still be adjusted as needed. One of my tabs had also broken.

alap · Joined: 17 Dec 2007 Posts: 156

thank you Manu,
I am puzzled though were this wear comes from - it was adjusted may be twice, with two new sails.
I guess it is every gust that tries to shorten the boom.... little by little...

what an expensive sport we are in.... still the best sport on earth - when it is blowing and your rig matches the wind. I'd say even better than powder skiing...

quigley · Joined: 23 Mar 2010 Posts: 58

Fiberspar boom lock kit ...try Windpower in Wisconsin for the replacement kit. Better than tape 😁

NOVAAN · Joined: 28 Sep 1994 Posts: 1548

You should be able to find new parts somewhere for that boom. I had the same issue a long time ago. As did others...