Best Way to Secure Guidance Fin

I have had a few boards with the Guidance Fin system installed. Usually these are damaged beyond repair, however I do have a nice Weber Ski with a good-excellent box and fin; it even has all of those little tabs you insert in the empty spaces of the box. 

Anyway, I’m working on a 60s Bing Good Karma that has an extra long Guidance box in relatively good condition so I decided to create a fin for this box. 

I made a mold of my good Guidance fin and then created a new fin from a busted FU fin plus Guidance base. Although this isn’t the prettiest solution, it looks like it’s going to work. But here’s my problem: I’m not sure how to secure the fin in that box so it won’t pop out when riding. 

When I insert the fin I slide it back into the Guidance slots and for the most part, the fin stays in the box. However, I’m worried it might slip forward and then fall out. Does anybody know of a way I could keep that fin in the box. Obviously I don’t have any extra tabs like I do on the Weber. I’m thinking about some sort of screw that acts just like a shower curtain rod; as in I would be able to ‘unscrew’ the rod to make it longer, thereby wedging the fin in the box. Is there even such a thing as this or should I consider something else? 

You could drill a pair of holes crosswise thru’ the barrel section of a Chicago Screw/Binding Post and loosen or tighten it with a small nail or such. Maybe flatten the screw ends for better hold. Or maybe a stainless compression spring… 

 

Yes, something like this. I didn’t even have any idea what they were called so that points me in a direction. Thanks.

Think you could post a pic of the box and the base of the fin.  Just trying to visualize what you are after.

Since you already have some channel caps for your Weber, maybe you could replicate a single cap to fit in front of the fin and prevent it from popping out? Possibly two sizes so it can be adjusted some? Know anyone with a 3D printer? Also, since you did a molded copy for the fin, why not mold caps as well?

You’re right. I was thinking about molding the caps. If I like how it rides, I probably will do that. 

Guidance systems fins and boxes, I think there was a Fins Unlimited variation on that theme too? Perfect example of ‘great idea, lousy execution’, a fin system that didn’t need any tools to install or remove…except a hammer, a pad or two, something to dig out the spacers, more spacers in your pocket… yeah. This is why sometimes you should give up and start over, when what started out as a good idea collapses. 

The 3D printing is probably the easiest, if you have access to one, check your local engineering school for instance. .Or do a search for modellers in your area. 

Failing that, spend some time looking at various catalogs of plastic extrusions, cut and rasp to fit? Here’s someplace to start: https://www.pexco.com/custom-plastic-extrusion/capabilities/methods-extrusion/?_vsrefdom=ppcbing&utm_source=bing&utm_medium=CPC&utm_term=%2BPlastic%20%2BExtrusions&utm_campaign=PriorityPlastic%20Solutions&utm_source=bing&utm_medium=cpc&utm_term=%2BPlastic%20%2BExtrusions&utm_campaign=Priority&msclkid=e52b4e1f72e51d6b48b6114e5089bfed&utm_content=Plastic%20Extrusions

hope that’s of use

doc…

Yeah O’Fishl had it going on too.  Like you said execution.  But they were up against stiffer competition in Futures and FCS.

Never mind the pics monk.  I remember the system and yes new caps would be your best bet.

Guidance has a series of dovetails. Male on the fin, female in the box. A similar design was done by Simplex in Australia, and also at the very end of the Waveset line. The Simplex and Waveset were square cut male and female mating rather than dovetails. FU did not do anything similar.

I have a scan of a second gen Waveset ad somewhere, but cannot find it at the moment. It was nearly identical to the Simplex system. By the time that the WAVE company began making hollow boards they had switched to using the FU box still in use today.

I managed to find some pics of the second gen Waveset system online. They are kind of small, but you’ll get the idea. Similar to Guidance in concept but with square notches. Second pic is a closeup of the box.


Wave set, yep, that’s the one. I was never entirely sure how those worked, though I put in a few of 'em. Set 'em in the fin box, whack smartly with mallet, hope for the best. 

Speaking of horrible fin systems, remember these? The variable Wave Set: https://www.ebay.com/i/114356976103?chn=ps&norover=1&mkevt=1&mkrid=711-213727-13078-0&mkcid=2&itemid=114356976103&targetid=4580977766998583&device=c&mktype=&googleloc=&poi=&campaignid=403204665&mkgroupid=1238050308086972&rlsatarget=pla-4580977766998583&abcId=9300377&merchantid=51291&msclkid=c4bd5919a4e71274558306483f238703 - this one is in the filled black plastic version that had some faint durability, but the more common Lexan ones were good for about 1 1/2 botton turns in cold water before they broke.

The thin flanges at the ends had the strength of old eggshell, a little strain,  snap and they would be gone. Must be hundreds on the bottom someplace. 

 

Somehow, we had a couple hundred of the complete units I think we got from Weber, very fragile Lexan fin in a revolting translucent chartreuse, box insert to replace a full sized non adjustable fin, four Allen screws (two round head for the fin, two flat head for the insert) and a stainless slider that went in the thing. Wound up with a couple hundred box inserts, screw sets and stainless sliders after using the fins they came with as replacements. Very short-lived replacements. 

Probably still in a dusty box somewhere… 

doc…

Sure do. I had the Variable Waveset in a 6’9" Sopwith Camel back in 1969. It had the fiber reinforced black fin which held up rather well.  I rode that board to death in about two years. Replaced by a Weber Pig with a Guidance fin, which was a big step backwards.

Right? That was the era of the new ‘you gotta have this’  model boards that came out every year or two, the Weber Pig and the G&S Egg as perfect examples. Wide-assed, short-ish things with rounded noses and tails, mongo big stiff fins, I never figured out quite what they were good for. 

Around then too were the first twin fins, that only Mark Richards could do anything with - the only ones that went through our shop were a very few for people who wept, wailed, gnashed their teeth and rent their garments and demanded them. Result? The next year, when something else came along, well, I know one shop that went under trying to do the right thing and take twin fin trade-ins they could do nothing with. Which went into the back room and gathered dust. Guy who owned the place died recently, I wonder if they are still in a storage unit or something. 

We lived to fight another day.And even more skeptical about the surf biz.

The industry kept coming out with the new hot things every year and only a few worked. Boards like that Camel and the Ski and G&S’s Magic of that era, the gunny ones Bill Thrailkill mentioned in another thread and eventually the fun shapes that Joe Everyman could ride most days and have a good time with rather than somethying endorsed by a Spicoli clone that won a few contests. What a concept. 

Nope, don’t miss that at all. 

doc…

The egg was pretty much a Skip Frye design and totally unlike the Weber Pig. It is a tried and true shape with the wide point forward of center, no hard edges, and truly blended curves throughout. I rode a Tony Staples egg for many years and it is one of the best boards I’ve ever had. Perfectly suited for east coast waves.

Incorrect. The early 70s twins were indeed an abomination. Super wide tails, no toe in on the fins, and generally well under 6’ in length.

Richards adopted a twin fin design he borrowed from Reno Abillera in the mid to late 70s. They were nothing like the early 70s twins. Swallowtails for the most part, and over 6’ with a more balanced outline than the early 70s twin dogs.