[Public-list] sail track

[Michael Connolly]

Hi Gord,
Appreciate your comments.  The reason for my longish message was to help Jon avoid some possible mess while reinstalling mainsail track.
 
If the original holes were filled with some body filler, "Bondo" or some other synthetic resin, then they are not filled with metal and are still holes from the Engineering sense.
 
If Jon does not locate the original holes to either use them or to miss then with new holes then he runs the possibility of making a real mess by drilling partially into the old hole with the new hole.
 
Since locating the original holes might not be that hard, why weaken the mast by drilling new holes?   I understand that the Alberg 30 'telephone pole' rigid mast is perhaps over designed.  But new holes beside improperly filled original holes will weaken the extrusion.  Weaken it enough to cause a failure?  Probably not in most circumstances, but I for one would not want to be the one to find out.
 
I agree that fooling around with severly bent up sail track is not worth the time and later hassle.  Depending on finances and how badly bent the original track is, I would consider one of the newer sail track/ sail slide systems available.
 
What ever sail track I would install I would definately try to reuse the original mast holes if at all possible.
 
Michael

Gordon Laco <mainstay at csolve.net> wrote:
Hi guys - 

I respectfully disagree that drilling new holes will have compromised an
Alberg 30 mast. (don't you just hate conflicting advice?)

Our sticks are what we used to call 'totem pole' masts - quite a bit heavier
than they need to be in thickness, section etc etc. In addition we have
standing rigging that ensures that our sticks are nearly totally in
compression, so holes don't matter much so long as they are round. (square
'holes' concentrate stress to the corners)

Drilling holes is detrimental in masts that are built to minimum scantlings
and are rigged such that they bend a lot and repeatadly. Our masts have to
cope with neither situation. Also, in any mast, a hole is no longer a hole
in engineering compromise terms once it is filled with a steel or aluminium
fastener that fits.

I think that people realized the possible danger caused by cutting into alum
masts when people started putting halyards inside - which created a need for
exit boxes or slots. Those did indeed cause problems especially when they
had square corners. And of course the boats whose owners cared about saving
windage by setting up inside halyards tended to be boats with very light
bendy rigs...

I don't think that it is possible to repair bent track. I would suggest
that you would save yourself a world of future frustration if you just
replace the track. Not really a huge expense in the scope of getting your
mast functional again but probably just about the best money you could
spend.

Re attaching it - my preference is to drill and tap the holes then fasten
the track with fine thread machine screws. Rather time consuming but not as
bad as it sounds once you get going. I put the tap on a variable speed
drill, and have a sep drill for the 'drilling' so you are not constantly
changing bits.

By the way - my advice about the track is given with a pure motive; the
track I sell is brass and while in wooden rigs that is superior to SS, it is
not compatible with aluminium (that old dissimilar metal thing...)

Well - there is my view.

Cheers - Gordon #426 Surprise











> John,
> Your concern should be to NOT drill any more holes in the mast to replace the
> sail track!!!! Find out what they used to fill the holes. Fortunately, you
> have the old track to use as a template to locate the original holes. You
> will need to be very careful to determine the sequence of the original pieces
> of sail track. Then find the last hole at either end and carefully relocate
> the original holes. Either straighten the original track and reinstall or use
> the original track as a template again to drill holes in your new track.
> 
> My concerns would be you don't want to weaken the mast by drilling another set
> of holes. If the holes were filled with some nonstructural filler, i.e.,
> resin then if you drilled a new set of holes helter skelter you might drill
> the new hole partially into the diameter of the old hole and the holding power
> of the fastener will be severely undermined. If the yard guys were careful in
> drilling out the old rivets then the BEST solution would be to go back into
> the original holes with the original size rivets. If the yard guys were
> careless and oversized the original holes then the SECOND BEST solution would
> be to use the next size larger fastener into the now oversized hole. You then
> need to be cautious to size the head of the fastener so that it will not jam
> in the sail slide.
> 
> You might be able to determine where the original holes are located under the
> new paint by taking a light and placing at one end of the mast and then
> looking down the mast toward the light. It would be better to do this at dark.
> The 'raking light' might show the filled holes as darker dimples. Once
> located, use a drill smaller than the hole to locate each hole. Then use a
> countersink to open the hole and carefully cut away the new paint to just
> slightly larger that the original sized hole, only at the surface!!! If you
> carefully rock the countersink in a circular motion as you enlarge the hole it
> will normally center itself in the hole and not mess up the new paint around
> the hole. Then go back with the proper sized drill for the fastener you intend
> to use to open the hole thru the mast.
> 
> These guys did you no good service by filling the holes prior to repainting.
> 
> If the yard welded the original holes closed, then you can throw away the mast
> or use it for a flag pole because via the welding and heat they have ruined
> the temper of the Aluminum.
> 
> Good Luck,
> 
> Michael
> 
> "Budington, Jonathan" wrote:
> The track was damaged when it was removed (bent) and the holes in the mast
> were filled before it was painted. I have the sail track and planned to put
> it back on - the person who replaced the rigging told me I should replace
> the sale track.
> 
> Jon
> 
> -----Original Message-----
> From: George Dinwiddie [mailto:gdinwiddie at alberg30.org]
> Sent: Thursday, January 06, 2005 9:16 AM
> To: Alberg 30 Public List -- open to all
> Subject: [Public-list] sail track
> 
> 
> Budington, Jonathan wrote:
>> One thing I do need to do is replace my sail track. The mast was painted,
>> and they didn't do a great job removing the old one. Any suggestions?
> 
> It's hard to make suggestions when I don't know what is the problem.
> The sail track is normally pop-riveted to the mast.
> 
> Did they damage the old sail track in removing it? Is that the problem?
> 
> - George

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