How’s it going? Just about done with a 5-11 x 21 x 2-3/4" MR inspired Retro Twin. flat deck and what i think are older style rails.
I plan to ride mainly in Texas gulf coast waves.
His design, from what i’ve read, has vee nose to tail, and a hard edge nose to tail, and a good amount of rocker.
What i’ve done is lower the rocker and added vee at about the last 1/3 of the board, and flat the first 2/3. (i felt nose to tail vee would create too much drag for the week gulf coast waves)
Because i’ve lowered the rocker, and only added vee in the back 1/3, is the hard edge needed the length of the board, or just where the vee is? when i say hard edge, aside from the last 16-18", i mean that i have added tuck, but have not blended in order to maintain edge…in case that is wrong terminology.
Just drop the rail however deep or shallow you like your vee. If you want more of a panel vee you let vee carry out the tail tips.
What I did was figure out where id set twins, make a pencil mark in front of fins, then measure down the side of blank how deep you want vee…1/8" is what I did. 3/16" would be ok if you want it good and maneuverable - but not be a slug. 1/4" is getting extreme. I’d say 3/16" would be k for a twin.
Maybe someone who knows more about Mark Richards twins can chime in. Those are nice board’s.
You can use a hard stick also to check your vee depth, but it’s tricky. That’s why I do a pencil mark.
Yeah, just use a surform or a block, get behind there and hold your block at a 45, and plow off sum edges, on the up stroke you’ll be at the top side hold n surform horizontal to bottom and down stroke I kinda pull it towards stringer, or fade to zero if you want less vee out the tail block.if you want more of the vee to carry out the tail, just pull the block towards stringer…
Try to angle the surform or block, and stay off the middle. Other wise you tend to get a mound…you want a nice n flat panel where you can see and feel the vee …
As for the hard edge, yeah it seems to start in front of fins, or a tad forward fins (upboard)… the rails up board seem to generally flow even all the way if hard 1/8" -1/4" for a harder type edge…and 1/4" + for more of a rolled round rail. I tend to prefer 1/4" on twins ive owned. I’m experimenting w hard rail 1/8" @ edge… but I think twins should be about 1/4"… and up near nose about the same, or a bit of a progressive rolled edge…tucking edges under is what I did. But I faded out @ fins and out nose. Just made a slight dip on the edge on flats with side of of my block lengthwise, and blended w screen lightly w finger…
Older style down rails are still popular on board’s. Basically a low rail. Bottom edges can vary. Some prefer hard, some a kinda rounded edge, and leave it hard behind the leading edge of fins. Any rounded edge I think should start even a bit forward fins…
But yeah, you should lightly dull the edge from fins back. But I start my block sanding at a 45 from tip end forward… that way I get it all. It’s kind of a gradual flow. And near nose you gradually fatten it if you want. Then gradually round the corners from fins up to nose. I kinda wrap 275 grit sandpaper to do it.
I always start flat panel vee’s with a railband done with the planer. Once the railbands are done you flatten them out going toward the stringer which is left high. Sanding blocks clean up the final product. Old school stuff I guess.
I actually have an MR twin about the same size in the back yard right now, waiting to be templated & measured. What stands out to me about the design is the…dunno what you’d call them…the downward projecting extensions in the board itself at the wings; they’re the main reason I haven’t measured it yet.
Not quite on subject, and not to derail your thread topic, but I just came in from surfing some FCS MR-TX fins (big, fat fronts, small trailer) on a board I made that just SUCKED on it. For the life of me, I cannot come up with any explanation for why they work so well on some boards and not at all on others. My boards almost all use the same or very close fin layouts, and I cannot predict at all when they’ll work well and when they won’t. On some boards they seem to speed the board up and on others they seem to slow it, even when toe is the same.
If anybody has any insight on either subject (the ears on the MR board wings, or what makes the MR-TX fins hit or miss) I’d like to hear it.
Have you tried other fins on this board? normal thruster fins are smaller, maybe use a different pair on the fronts if ur using boxes.
I don’t think I’ve tried Mark Richards fins? I’ve seen a couple MR twins at a surf shop (not copies). They kinda look like a cross between a old school Fish and a rocket fish, but w wings. Those designs were EXTREMELY popular in the early eighties. The one I tried had a concave deck, and was around 22" wide. It was pretty fun. The wings make the turns a bit looser feel to it. There’s a similar thruster I just saw on a Procter surfboards vid on YouTube - that’s a different animal, but has the similar tail and possibly MR Fins setup? You might want to take a look - It might give you clues. His board seems to blaze!
Not sure, but I’m thinking he may have cut the fins down?
SammyA has made a worthy suggestion to you. Make another trip to Ace, and pick one up. It was ‘‘standard issue’’ among production shapers, before the advent of the ‘‘shapers square’’, so popular now. FWIW, I second his suggestion.
thanks -SammyA - I got a cheaper Stanley tools square. But I f’ing left it in storage…gotta pick it up. I use the cheap wood yard stick to kinda check vee, concaves etc…it works nice as it won’t gouge the blank easily ! Thanks man.
I got two squares, but I gtg get them soon. But yeah, I used a shapers rectangular type square -rooster has. I’m going to shape another board aft glassing the build I just did.but THANKS! I’m thinking about making a semi gun, or something different? Enjoy your Gun build! -JIM
OPS" framing square is a 40 something year old and rusty, haven’t used it since the ‘‘shapers square’’ came out.
A real time saver! Really killed it on parabolic stringer jobs dead nutz. On my second one (they don’t rust but ez for mez to abuse and snap) and notice the fin placement “guide” (HA) has been covered up…