mustoskiff.com

Ok ... lets try and capture some facts to move the conversation forward ...

1) The incidence of these type of failures seems to be on the increase (but is that just the fleet getting bigger???)
2) Up until 2007/8 ish these failures seemed to be very rare (smaller fleet so smaller sample??)
3) The trend over time has been to use more batten tension and downhaul
4) In 2008ish the baulk rope changed from rope to solid plastic
5) At some point the track extrusion section changed (similar era)
6) We don't really know if the failure is the track being crushed on the leeward side or levered out on the windward side (if it is the latter the progrip idea may make things worse)
7) Time, temperature cycles will make plastic less plastic
8 ) The fleet is aging so there are more old masts about, although plenty of new masts have failed
9) The fleet is now grographically disperse so more masts are being exposed to more extreme environments (very hot places)

So ... where does that leave us??

Personally I think this is down to Selden and the specification of the plastic track, perhpas the glass/nylon % has changed a bit or the temperature of the extrusion process has changed. The current track seems a little to brittle and not enough flex, although it needs to be stiff enough that the baulk rope does not come out.

A small tweak to the plastic composition/process perhaps would fix this ...

Other solutions perhaps would be to shift the batten pocket back a few mm to give the pocket to move about a bit more where it butts the mast but that wouldn't be great for the sail shape.

Thor

All constructive feedback is most welcome, thank you.

I spoke to Chris Turner yesterday and he has agreed that I should speak to Selden on this subject.

paul manning wrote:I spoke to Chris Turner yesterday and he has agreed that I should speak to Selden on this subject.

Paul, I recall you & I going through this at least twice with Selden at yearly reviews, can we find out who it the plastics expert there and deal direct with them? I wonder if the issue gets lost in translation ???

Is it that the black plastic track on the masts is getting brittle with age, the boats are older now? I think the mainsail would be tricky to pull up in breeze without damaging the progrip on the first hoist.

Oh, if it was that...

Sadly, we've had boats that are new breaking it.

Good thought though!

[quote="Rick"]Paul and I have discussed this with Selden a number of times and they state that the material they use is the best they can source. It has to be stiff enough to retain the bolt rope but also flexible.

In the past though, they were obviously able to source a higher quality material! This is a serious issue with the durability of the mast and Selden should really not ignore this problem.

to me that's a one-design class side effect. Having no competition manufacturers think they can get away with anything. I think the class should find some incentives for them to maintain high quality standards. Maybe issue a penalty notice based on estimated loss by members of the fleet making endless repairs + emotional damage for missing important races. There also should be an option to switch to another maker if the class is seriously dissatisfied with the existing one.

there are several more issues crying out to be solved by manufacturers. Off the top of my head they are:
1. Shroud bolts (keep snapping with a rate of machine gun in spite of having been "improved")
2. Lowers (keep snapping also)
3. Kicker arms (routinely destroy the main). They should be modified

Serega wrote:1. Shroud bolts (keep snapping with a rate of machine gun in spite of having been "improved")
2. Lowers (keep snapping also)
3. Kicker arms (routinely destroy the main). They should be modified

Points 1 & 2 have already been addressed in the recent survey and upgrades coming in by way of stronger items.

Can you expand on point 3 in a new thread, lets keep this one about tracks.

BTW I think some people are more heavy handed and aggressive with their kit or perhaps don't look after it as well as others. I have over 5000 hours of MPS sailing logged and I have never broken a shroud bolt, lower, mast track or vang lever

broken luff tracks....

I think there may be a tendency for more recent breakages due to the change from old bolt rope to newer plastic luff tube.

Possibly due to change in diameter? batten sockets now closer to track? not sure if this is a design thing or perhaps when sockets are reattached if you have your bolt rope changed out?
I went thorugh a phase of breaking a lot of mast track shortly after a bolt rope change out - probably coincidence but maybe not.

Besty wrote:I think there may be a tendency for more recent breakages due to the change from old bolt rope to newer plastic luff tube.

Agreed, see item 4 at the top of the page.

That said the plastic version is MUCH better for hoisting so I think is an improvement.

I'm sure the solution here is in the plastic qualities of the track (and not going mental on batten tension)

I will speak to Selden on Monday and report back

I bought a second hand sail and i broke the track at the end of every batten over 3 months training....proper pain in the backside, but it seems that when i got it over to Chris Henderson for a new bolt rope he said the tension in the battens was massive so perhaps that was a driver. I didn't change them as they came as the previous owner has a pretty untouchable track record

Hi Everyone,

I don't have a Musto yet but this mast track convo has got me thinking...

1. It seems to be that ever since the bolt rope has been changed to plastic (I'm guessing it was pulling out due to the load on the bolt rope), the mast track has broken as the plastic is stronger than the track.

2. On the I14 at the club they use a carbon mast track (bit of carbon tube with a grove cut into it!) and a normal bolt rope and that never pops out or breaks. Carbon tubing will bend without a problem (clearly) and I'm sure won't cost much more than the plastic Selden are using now.

3. This is a drastic action but maybe the sails need to be re-designed slightly so that there is no need for the 'excessive batten tension' which seems to be the root cause along with the plastic bolt rope.

I know that these reasons will change the 'one design' of the class but isn't development part of improving the class? coming from lasers (one of the worst one design classes) there have been development in sails (gone from Hyde to North), new GRP foils, new boom blocks ect ect.... all have slightly (and i mean slighty) improved the class with not a hugh amount of performance gain.

Looking forward to your replys

Sam

Sam

Thank you for your comments.

I think the biggest problem we are wrestling with is that the track never used to break, so something which may seem insignificant is now causing failures.

The class technical committee in conjunction with the sailors review everything that may be an issue on an annual basis and, as you quite correctly say, are not frightened to recommend changes to better the product. In fact there is a historical list on the website which shows what and when amendments were made.

Ive seen both the old and the new bolt ropes present with track breakage. And seen it happen to old boats and fairly recent boats.
Since repairing a section of my track a few years ago, I started using much less batten tension because I was sure it caused the track breakage, and no breakages since! May not be the fastest but its more considerate to the sail and mast track. Also noticed the end protection caps were damaging the sail material because of the high batten tension.
Perhaps if there were more battens along the luff then the level of sail ridgity people are after could be achieved with less batten tension and consequently less stress on the mast track.