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mike
8th October 2006, 12:00 AM
For my Kombat, I mostly sail with the footsraps in the outboard positions. If conditions change such that I want to move the straps inboard, can I do this when the board is wet? My concern is that inserting the footstrap screw when there is water in the hole will cause cracking from the pressure.

Roger
8th October 2006, 09:20 AM
Hi Mike,
There should be no problem with moving your footstraps when the board is wet.
There is enough clearance at the root of the special PT thread to allow any water that might be trapped to escape out of the plastic FS insert holes.
I would suggest however that you carry a bar of soap and use it to lubricate the footstrap screws whenever you are screwing the the FS screws into a new hole that has not previously had a screw installled.
Also, be sure you use either the Tiki Tool or (much better) a good #3 Philiips screwdriver with a hardened and treated tip.
Use of a good tool here will make yourFS screws last virtually forever.
Do not use a cordless "power driver" as this can rotate the screws at a rate that generates too much heat and can cause you to get poor thread engagement and premature failure of the FS insert.
It won't leak, but you cannot tighten the FS screw to it's full torque, which will reduce the "pull out" strength significantly.
Hope this helps,

Screamer
9th October 2006, 08:07 PM
Hi Roger

I've tried different FS positions on my K86, and now I've left them in middle/single back mode, since it's always used in big chop/swell, etc. Nevertheless I'd like to hear your opinion on this: you mention "premature failure of ths FS insert". If someone regularly changes fs positions (out/middle), like every few sessions, how much can one expect those plugs(inserts) to last?

mike
10th October 2006, 12:06 AM
Thanks for the feedback & tips Roger.

Roger
10th October 2006, 06:44 AM
Hello Screamer,
It's like almost any other "mechanical fastening" system.
If you use the correct tool (a high quaility #3 Phillips screwdriver with a
hardened and surface treated #3 Phillips drive on the end); you
"lubricate" the threads (by rubbing a bar of soap on the threads of the screw), and do not use high speed (rotational speed here) "Power Drivers" you can expect your footstrap screws and the inserts to last almost forever, certainly well beyond the normal life cycle of a board.
When you move your footstraps, try to get the screw to start in the "already formed" threads in insert holes that have been used before, and re-lubricate them each time with a small bar of bath soap.
If you use "power screwdrivers" that rotate the screw fast enough to generate friction related heating of the screw, don't lube the screws to make them go in easily and significantly tighter, or use a tool without the correct #3 Phillips geometry plus heat treatment and surface coating to preserve the integrity of the Phillips drive recess, then you will almost surely end up with some degree of premature insert damage or failure.
I've seen a few new boards that had poor quality inserts that stripped out very quickly, but for the majority of "premature failures" of FS screw inserts, there was a definite "cause" mostly related to one or more of the above installation no-no's.
Hope this helps,

RobSwift
13th October 2006, 06:21 PM
It wasn't on a Starboard, but I cracked a footstrap screw insert. I think it was due to moving the straps around on the board i.e. pulling the screws out and putting them back. I stopped doing this. The crack wasn't bad and holds the footstrap, but I don't want it to get worse.

Roger
15th October 2006, 11:26 PM
Hi Rob,
You can fix that "partially stripped" or cracked insert quite easily.
Get a Permatex or Lock-Tite Stripped Thread Repair Kit"
Here's a link:
http://www.accessconnect.com/loctite_threadlocker_.htm
Simply coat a new footstrap screw with the blue "release agent" that comes in the kit, then mix up a little of the 2 part epoxy thread reapir
compound, push the compound down into your stripped or cracked FS insert hole with a tooth pick or other suitable small round tool.
Put enough compound in so it looks like the damaged hole will "overflow" slightly when you screw the blue release agent coated screw into the hole.
Install the screw into the compound filled hole slightly further than it would go with the foostrap webbing, the anti-twist device, and any washers you use under the head.
Let the compound set up.
Remove the screw, countersink the hole slightly to remove any "compound overflow" and you'll have a nicely repaired FS screw
insert that has very nearly as great a "pull out strength" and torque retention value as a brand new insert.
It's good stuff to have in your repair kit.
Fixes stripped fn screw barrel nuts or threads in the head of fins (like Tectonics does), loose fin screw barrel nuts, stripped vent plug threads and stripped footstrap screw inserts.
Hope this helps,

Roger
15th October 2006, 11:26 PM
Hi Rob,
You can fix that "partially stripped" or cracked insert quite easily.
Get a Permatex or Lock-Tite Stripped Thread Repair Kit"
Here's a link:
http://www.accessconnect.com/loctite_threadlocker_.htm
Simply coat a new footstrap screw with the blue "release agent" that comes in the kit, then mix up a little of the 2 part epoxy thread reapir
compound, push the compound down into your stripped or cracked FS insert hole with a tooth pick or other suitable small round tool.
Put enough compound in so it looks like the damaged hole will "overflow" slightly when you screw the blue release agent coated screw into the hole.
Install the screw into the compound filled hole slightly further than it would go with the foostrap webbing, the anti-twist device, and any washers you use under the head.
Let the compound set up.
Remove the screw, countersink the hole slightly to remove any "compound overflow" and you'll have a nicely repaired FS screw
insert that has very nearly as great a "pull out strength" and torque retention value as a brand new insert.
It's good stuff to have in your repair kit.
Fixes stripped fn screw barrel nuts or threads in the head of fins (like Tectonics does), loose fin screw barrel nuts, stripped vent plug threads and stripped footstrap screw inserts.
Hope this helps,

steveC
16th October 2006, 12:44 AM
Hi Roger,

I really appreciate your insert fix outlined above. Its good stuff to know. While I have never had a problem with inserts stripping out, I currently have a Tectonics Goldwing where one of the tapped threads is stripped. Sounds like a perfect fix for my problem. Many thanks.

Ian Fox
16th October 2006, 02:56 PM
Steve, Roger's totally right on the threadlock, it has saved the day on more than one occasion, but if you're big or powerful or gonna change it often or just plain go hard on it, for the stripped epoxy TT thread get some brass threaded fin inserts (old fin or local dealer's old fins if you can't find these easily).

Drill down (drilling out) the threaded (stripped) tapped threads to oversize the hole, then carefully drill sideways thru the TT head to insert the brass thread inserts. There's a few pointers to be aware of, most notably accurate setup and square 90' drilling (use a workshop drill press, esp for the sideways insert hole/s. And overdrill (not toooo much) the depth of the bolt holes by a few mm deeper than the bottom of the insert holes ; this allows the fin bolts to screw thryu the insert and out the other side- at least a little_ before they start to impact into the base material, at which point extra tension starts to pull the insert right thru the top of the base material and :o or even :(

Sounds complex, with the inserts in one hand and the drill press in front of you, it's a no brainer and brings an otherwise good fin back to full and reliable long term service.

Cheers ~ Ian

WSguy
16th October 2006, 09:17 PM
Thanks Roger. I filled the crack with 2-ton 2-part epoxy and screwed the strap in while it was still wet. With this board, I decided to keep the straps in one position and not bother to move them around. If this repair doesn't hold up, I'll try the one you recommend. I'm also going to bookmark that URL and perhaps pick up a stripped thread kit for my shop.

steveC
17th October 2006, 02:25 AM
Hi Ian,

I understand where you are coming from going with the optimum fin fix using the brass threaded inserts. Truely, it's the best possible fix for stripped fin threads. Earlier, I discussed this repair approach with Chuck Ames of True Ames fins (his firm is located just a few miles away), and he indicated that he would gladly install the brass inserts for me. I just haven't done it yet. Also, given the fact that the stripped thread is the rear one on a Tuttle base, it's my thought that the Cadillac repair isn't as much of a necessity. In any case, your post above greatly appreciated, and I know that many will find advantage in this best possible repair strategy.

Roger
17th October 2006, 06:40 AM
Hi Ian, Steve, and WSGuy,
The Permatex-Locktite Thread Repair Compound is NOT a "thread locker" (although LockTite is famous for their many different grades of "thread lockers").
It's a completely different product that results in high pull out strength
basically new threads after it sets up completely.
Another "option" for Tectonics (and other high end fins with the fin screw threads tapped directly into the G-10 or the casting plastic the fin head is formed from is to use a Keen-Sert SS thread insert.
Just tap the hole to the next oversize (.25-20 UNC gets tapped to .312- 18 UNC) and install the threaded stainless steel insert.
Then drive the locking keys in and you have a very high strength fastening method.
Biggest problem with Tectonics, is that Dennis puts the holes with the threads in them precisely where Larry Tuttle's drawings specify they should be, but if you don't "slot" the fin screw holes in your board, you often end up with a little misalignment. This causes alot of problems and prematurely wears the threads in the G-10 and fin head plastic.
Wish all the board mfg.'s would use Larry's drawings and tolerances (especially for hole locations). Then everything would fit pretty much interchangeably.
Hope this helps,

RobSwift
18th October 2006, 06:03 PM
Roger, thanks for all the info. I'm looking around in local hardware and auto parts stores for that Permatex product.