Dec 5, 2008

Modified UDT's

These are my current UDT fins. The spines were shaved down with an extremely sharp razor plane, and then smoothed over with 80 grit W/D sandpaper glued to a small wood block. I did the final hand sanding under the faucet to facilitate the process.

I tried to replicate the flex of an old duckfoot fin. I left it a bit stiffer so I can approach the final flex slowly. As you can see, the top spines are a bit taller than the bottom. I thought the fins might have a bit more "direction" when kicking downward with more top spine. I've never liked fins with the top spines trimmed away too much. They kind of wander side to side as you kick.

My UDT's haven't been shortened as of this time. They feel pretty good in the water, but are a bear getting over rocks. Since I'm not in the water these days, it's all academic!

The Med/Lrg size (smallest available) is too long for my foot, so the heel is padded with neoprene. The top/inside of each foot pocket has two sheets of plastic from a milk container inserted to stiffen it up, and then a piece of neoprene to add comfort.

I'm currently looking at various brands of shoelaces to add that final touch of in-the-water security!


Jamie said...

What are you using for an adhesive for the plastic insert and the neoprene?

Anonymous said...

Hi Jamie,

The plastic insert is force fit into place, no adhesive. The plastic is trimmed to the exact shape of the top of the foot pocket, then slipped in.

The neoprene padding between the insert and my foot is glued to the top of the foot pocket with Barge contact cement. Barge seems to last the longest in the water. Regular contact cement comes loose pretty quickly.

I sanded the area to be glued on the top of the footpocket with 220 W/ remove the remaining mold release on the fin and scuff up the rubber. It takes a lot of sanding to get the area prepared for gluing.

I also let the first coat of Barge dry overnight before adding the second coat...and then bonding 20 minues later.

The heel strap neoprene is taped in place with thin strips of electrician's tape. No glue.

Jamie said...

I don't guess you documented the process photographically did you?

What did you use as a template to get the exact shape of the footpocket traced onto a milk jug?

I've gotta get mine rigged up before I leave for Oz, don't want to open up all my healing blisters from hurricane season.

We just scored a place to live within a bike ride to Burleigh!

Anonymous said...

No, no pictures.

I used carboard to make the insert template. I just started cutting out shapes until I got it close. (It's not critical, either.) Then I transferred it to some milk jug plastic and cut out three layers for each foot. Three was too stiff, two felt good, and one was too thin and flexy.

There are a lot of things you could use to stiffen the footpocket besides milk jug plastic...I just use it because it's free and handy.

I like the foot pocket to be pretty solid (and use the neoprene padding to protect my feet.) Then, the rest of the fin bends away from my foot.

An easy way to test two differing fins is to put one from each pair on each foot, and kick straight ahead in still water or a pool. The fastest fin will propel you in a circle in the the direction.

Unknown said...

Just got my new pair of UDT's yesterday so this is a timely post :)

Would love to hear more about other fins that mat riders use.

Jamie, that's great news...well done. We'll still have to get you down to Byron Bay which is mat capital of Australia.

Most weekday mornings you can find George and one or two other mat riders out at Wategoes. It's a pretty nice scene out of peak holiday time.

Anonymous said...

my brief fin history-Okespor boot/fin combos,Redleys for a long time,Fangz,Redleys,Techs,Viper V7s,UDTs,Flips,back to Techs,then one blessed day,Dafins!My dream fins at last-enough power,but SO comfy,no probs surfing everyday with no socks.And so light to carry in the stealth pack.You know the one,like Robert De NIro in "Heat",he can leave everything behind in 10 minutes....

Anonymous said...

Hi Paul,

Your pair of customized UDT's on Surfmatters are really cool. You've inspired me to, once again, pull mine out of the closet and try to visualize what it would take for me to like them as much as my duckfeet...with foam (yoga mat) inserts which are just like butter on the feet and don't take too much out of you.

It seems like it's inevitable to move to the UDT's as time goes on just to squeeze a bit more horsepower out of fins and body too.

The plastic inserts you describe are genius, as the "sloppy" feel of the stock UDT's was my main gripe (not a sloppy fit, but a sloppy flex in the foot pocket rather than throughout the blade). That said, I have a few questions:

Did you (and George) wear Duckfeet for years before switching to UDT's? (I guess I'm asking about the history of modd-ing UDT's and when to make the switch.)

Have you ever tried or have you heard of George Greenough using split (propellor) fins for matting? The fins I am thinking of are the Oceanic Vortex V-6 (dive) fins. My thinking was that maybe they'd give more horsepower than Ducks without taking too much more outta ya.

Did you find for yourself, that you wore the modded UDT's in more expansive situations (bigger waves, stronger currents, long paddle outs, etc.) and then went back to ducks in everyday SoCal surf?

I know it's all personal feel, but your two cents is appreciated.

Thanks, Jeff

Anonymous said...

Hi Jeff,

I remember when we shifted over from UDTs to felt like we weren't even wearing fins! I agree, going back to UDT's is inevitble if you surf enough to stay in shape. And, there's enough material in the UDT's to make them into anything you want. It just takes time and patience to work them down.

As far as the plastic inserts are concerned...back in the 70's, George was talking about laminating a layer of glass/epoxy over the tops of the "new improved" duckfeet with flimsy foot pocket tops. We never got around to trying seemed like it would be too stiff to me. But I started to put the plastic inserts inside the tops of the "new improved" Duckfeet back then to stiffen the footpocket.

Yes, we rode Duckfeet a long time...for like 30 plus years. And no, I've never tried the split fins, and George has never mentioned it. But I wouldn't be the least bit surprised if something other than Duckfeet or UTDs are an improvement...those are very old designs. Proven, but old.

I did go back and forth between the Duckfeet and the UDts, and I missed the UDTs after going back to DF in smaller waves. I want to taper out the blades of the UTDs more when I get back in the water.

Marco said...

I glued 5mm neoprene in the foot pocket with shoe goo after I roughened it up with 80 grit sandpaper.I also added drain holes which took out alot of drag from the fins. Mine have 2 3/4" cut off and the rails were tapered also. I'm 5'10 and weigh 165lbs. and I use these fins for everything from bodysurfing, bodyboarding and for my recently purchased sea eagle surfmat. These things rock.