You can use ding stick easy enough. Those two part epoxy sticks are available at almost any hardware store. My only advice is to go minimal. I only made plugs about a cm deep. Minimal additional weight and easy enough to pick out if something goes wrong. A little tape over the threaded holes helps keep the threads clean. I did seal the unused threaded hole on the fuse end.
I wish I have seen your post earlier. I have 2nd generation (thin) LF mast, which main channels are sealed already. Yet, I decided to seal the threaded holes as well, and I have used foam for that. Clearly teflon tape, which is used for plumbing, would have sufficed and there would be less uncertainty whether future disassembly would pose a problem.
Really! that post was a direct response to you warning about the potential for a mess with foam. Hope it doesn't cause you problems, but you were warned. I don't think you'll have a problem taking it apart, but you might have a mess in there that you'll never get out potentially trapping water in, not out. Whatever, its a heavy foil anyway.
I wouldn't bother with teflon tape. Using a decent coating of TEF Gell on the threads keeps those channels sealed while assembled. Took mine apart a few times last year and never had any moisture in them. Riding only fresh water, I will only take it apart once sometime mid season next year just to have a look. Without the salt there has been zero evidence of corrosion after two seasons.
I raised the issue of mast water ingress in Tubeless Kite forum (French). It seems unavoidable, and filling the mast with foam is not advised. This is what Marie from Zeeko responded (sorry, I'm too lazy to translate):
Eau dans le mat du foil alu
Message Marie Zeeko le Mar 13 Déc - 9:14
je vous remercie d'avoir posé la problématique de l'eau dans les mats des foils alu sur ce forum. C'est une question que beaucoup d'utilisateurs se posent et la réponse est très simple.
Mécaniquement il est déconseillé d'essayer d'étanchéifier le mat car il y a tellement de contraintes appliquées sur celui-ci à la navigation qu'au bout d'un certain temps ce que vous pensiez étanche ne l'est plus. A partir de là l'eau s'infiltre et n'arrive plus à ressortir. En vient ensuite des problèmes de poids, de déséquilibre et surtout le plus important des problèmes d'usure chimique avec une corrosion du mat par de l'eau stagnante (que ce soit sur les foils Zeeko qui sont traité ou sur tout autre foil alu).
Zeeko conseille donc de ne pas tenter d'étanchéifier le mat pour ne pas risquer d'avoir de l'eau stagnante. Il n'y a rien de pire, il vaut mieux avoir un petit peut d'eau circulante et qui pourra ressortir... de toutes façons pour garder un foil en bon état il est conseillé de le démonter tous les 15 jours de nav pour le rincer à l'eau douce et appliquer du T-Gel sur les pas de vis.
Fort de ses années d'expérience et de tests, Nicolas a testé différentes techniques pour tester l'étanchéité mais aucune n'était satisfaisante pour l'appliquer sur nos foils. C'est comme l'histoire des foils alu/carbone, Nicolas teste le mix alu carbone depuis des années avec différentes techniques d'isolation entre les 2 matériaux mais il n'y a rien à faire, après plus d'un an l'électrolyse abîme considérablement le carbone jusqu'à rendre le foil inutilisable. C'est pour cela que nous le déconseillons et que nous ne le proposons pas.
J'espère avoir pu répondre au mieux à votre question, je suis désolé que ma réponse soit si tardive, nous sommes débordé avec la sortie des nouveaux foils (Le White & Green et le Spitfire) qui sont un vrai succès.
Anyone seal their zeeko (or other brands) alloy mast to prevent it getting logged with water? What did you use and did you seal both ends the same?
Thank you for posing the problem of water in the mats foils alu on this forum. This is a question that many users are asking and the answer is very simple.
Mechanically it is not advisable to try to seal the mat because there are so many constraints applied on it to the navigation that after a certain time what you think waterproof is no longer. From there the water infiltrates and can not come out again. Then comes the problems of weight, imbalance and especially the most important problems of chemical wear with corrosion of the mat by stagnant water (whether on the Zeeko foils that are treated or on any other foil alu) .
Zeeko therefore recommends not to try to seal the mat so as not to risk having stagnant water. There is nothing worse, it is better to have a small can of circulating water and that can stand out ... anyway to keep a foil in good condition it is advisable to disassemble it every 15 days of nav to Rinse with fresh water and apply T-Gel on the threads.
With years of experience and testing, Nicolas has tested various techniques to test the tightness but none was satisfactory to apply it on our foils. It is like the history of foils aluminum / carbon, Nicolas tests the alu carbon mix for years with different techniques of isolation between the 2 materials but there is nothing to do, after more than a year, Electrolysis considerably damages the carbon to render the foil unusable. That is why we do not advocate it and we do not propose it.
I hope to have answered your question, I am sorry that my answer is so late, we are overwhelmed with the release of the new foils (The White & Green and the Spitfire) which are a real success.
I don't have a sealed mast and remove the fuselage each session and the water that comes out is maybe 50ml. So that extra 50gms is not the problem.
You would add way more weight sealing it up. If the water dribbling in your car is the issue then simply loosen the fuselage bolts and let it drain out then tighten again. A 20 second exercise.
I took mine apart a few times this season and think it was overkill for a fresh water place. Moving forward I'll check and snug bolts every couple of weeks, but only take it fully apart maybe once mid season to have a good look and add a little tef gel to the threads. That plus a full dismantle for winter storage is enough. If riding in salt water, I would probably stick fairly close to manufacturers recommendations and fully take it apart, plate and all at least once a month to check and coat the threads.
At the beginning I would disassemble except for the plate every session. That soon became just the fuse from the strut, which just as quickly became just traveling day to day with it fully assembled. You end up riding so much, its hassle enough just attaching it to the board.
I sealed my mast pretty early on and it has held tight for a year and a half with no sign of stress. Will check it every year and if it ever leaks, I'll just drill it out and re seal. It's pretty simple and nice for day to day use not having to drain it.
I sealed my Liquid Force with marine grade silicone with foam plugs behind. There were two problems.
The main problem is that contraction of the air inside (after contact with cold water) sucked in the silicone and dislodged it so water could get in. Short of building up multiple layers of silicone I could not see a simple way around this. I did not want to use anything permanent like epoxy.
Once the water got in it was trapped inside. It was easy enough to remove the plugs and get the water out.
I eventually accepted that it was best to do a full pack down after each session. I could do maintenance and inspection on everything and it all fits very neatly in my car in the purpose built bags. It only takes 5-6 minutes at most.
The ultimate solution was to get better at foiling and moving to a full carbon kit ( http://www.jshapes.com ). It was only marginally more expensive than an alloy kit (from Zeeko). No water gets in. No corrosion. The whole board and foil kit weighs slightly more than an alloy foil on its own. The deep tuttle connection system only has 4 bolts in total. It's a pleasure to turn up the beach with a fully packed kit tucked under my arm and have it assembled in a couple of minutes.