Three Fins from the 70s

An FU ad from 1975 showing the Hynson Dol-fin, Brewer fin, and a Downing design.

All giving specifics on thickness, height, base, etc.

Thought some might find the info useful, or enlightening, at least.

SammyA - I am GLAD you posted the fins! FYI - the Hynson fin there was the fin I tried but didn’t know the name of it… I got about four times out on one but it was fantastic! It had tons of drive + turns were round! Ty for sharing.

OMG! I just noticed the 8" Brewer fin! I owned one - sadly i blew it and left it in my stinger I sold to a local…but I can’t complain too much because he might not have bought my board w out the fin…but I must say, it was a excellent fin! Mine was a rich deep dark blue. It held in real well, and it seemed ok even if I pushed it all the way forward in my old fins unlimited fin box.

IMO, the best looking fin was the Downing fin, but it did not  perform well in use, due to too great an amount of flex, as a result of its length.   The ‘‘Brewer’’ fin, was not designed by him, but a engineer friend of his.     The ‘‘Brewer’’ fin is an outstanding performer.    This is most noticable when it replaces an existing ‘‘normal’’ fin in an existing board.    The boards speed and performance will be wildly improved.    Counter intuitive, but true.    The thick foil is the reason for such dramatic improvement.     This performance difference of thicker foils was disclosed to me in conversation with Phil Edwards, in the spring of 1960.   He really opened my eyes, and mind, as it relates to surfboard and fin design.    I have no experience with the Hynson fin, but my instinct is that it would not perform nearly as well as the ‘‘Brewer’’ fin.

Bill

some from the period including my own a keel and those lexan stickon tirfin side bites











I rode both the Dol-fin and the thick plastic Brewer back in ~74; the Dol-fin was ok but nothing special, the Brewer a little better. Regular glass Brewer fin was better for me, and probably lots of others as it became kind of a standard for a few years there.

Thicker fins will handle AOA changes better than thin, but most of a fin’s drag is directly proportional to frontal area (especially if everything else is held constant). IMO they went a little too far with fins ~1" thick - both the Dol-fin and plastic Brewer were slower than other fins of the time.

I always liked my Downing fin.  The foil was thicker than standard fiberglass panel fins.  I found mine in a weird place… waaaay inside Morro Bay in the mudflats on a low tide day.  I have no idea how it got there but I picked it out of the mud, cleaned it up, and it became a favorite.  As mentioned, the thicker foil foil allowed a wider angle of attack with less drag.  The vertical orientation and narrower outline seemed to allow for quicker rail to rail transitions.  I never noticed the flex issue Bill mentions but I did not use it in bigger surf much over head.  The thicker foil is a feature still on certain modern molded plastic fins.  Too much waste with fiberglass I suppose - to build up all those layers to get decent foil thickness only to grind a lot of it away.

Awesome!  Thanks for posting.

I have one of the Brewer fins that is now out of commission due to the plastic screw tab breaking.  Still happy to own one.

Of the three pictured I had both the Brewer and Downing at one point or another. The Brewer actually had a fiberglass core with plywood laminations on both sides to attain the thickness needed. It looked kind of cool because of the glass halo achieved by the way it was made. The fin worked well on a 6’8" swallowtail. I used the Downing fin on a 6’4" egg for a while, but I broke it on a rock. It was replaced with a 9" 4A.

I remember reading about the Dol-fin back then, but had no idea it (and the Brewer) were so thick.

Must have been about the thickest production fins ever released.(?) Maybe too much, but good thinking though, makes sense in terms of flow. (Remembering something from a really old thread, the counterintuitive effect of a wider, rounder leading edge actually creating less drag because of boundary layer laminar flows or something.)

Thanks for posting those Sammy and Oneula.

Bill - I tried all three fins listed although I never bothered finding out the names of the fins… FYI - my primary fin was a Brewer 8" fin on a 6’10" late 70’s shortboard and it was the ideal fin for the board. Also, I tried every fin a friend had, but none had a Hynson, or a Downing fin…  The Brewer fin felt the best so I put it back and quit my testing phase.

About a yr later my brother befriended a old surfer who ended up selling him a board with a Hynson fin in box… At first the fin felt awkward, but after using it I must have gotten used to it. It felt almost fish like in turns - almost swively…it had an almost stiff pivotal unbalance in a turn, but would jet you forward in short bursts of sluggish speed…maybe the foil was wrong being so thick?but I’ll give it this: the fin felt pivoty in turns, not very drivey, but other wise funcional. I would own one just to use on slow days where hold is a non- issue. Now I voted on the fins - I’d vote in favor for the Brewer.

Bill - I tried all three fins listed although I never bothered finding out the names of the fins… FYI - my primary fin was a Brewer 8" fin on a 6’10" late 70’s shortboard and it was the ideal fin for the board. Also, I tried every fin a friend had, but none had a Hynson, or a Downing fin…  The Brewer fin felt the best so I put it back in my board and quit my testing phase.

About a yr later my brother befriended a old surfer who ended up selling him a board with a Hynson fin in box… At first the fin felt awkward, but after using it I must have gotten used to it. It felt almost fish like in turns - almost swively…it had an almost stiff pivotal unbalance in a turn, but would jet you forward in short bursts of sluggish speed…maybe the foil was wrong being so thick?but I’ll give it this: the fin felt pivoty in turns, not very drivey, but other wise funcional. I would own one just to use on slow days where hold is a non- issue. Now if ,i voted on the fins for a short board - I’d vote in favor for the Brewer. As for a longer I don’t have a clue what I’d want as I’m primarily a short boarder. 

I’ve employed the ‘‘Brewer’’ fin on Broomtail Fish, 6 feet long, and on up to 9 foot 6 inch long pintail big wave guns.     Trust me, the fins were excellent performers, on all of those boards.