Hi, folks. I was bored on Sunday, so I just started hacking away at some foam. Wound up with this 5’8" retro biscuit thingy (yes, that’s the technical term). I didn’t actually measure much anything when I shaped it, so I’ll head back to the workshop and get some numbers as soon as I get a chance, but in the meantime, does anyone have suggestions on placement for a ProBox fin system ???
Do you have a picture?
I am making a similar type of board, I think (round tail, speed-dialer type board), and I am going to put 4 or 5 proboxes in. Still debating on the fin placement.
just finished a 5.8 disc/biscuit
with lots of boxes
Center 10.5" box rear of box 3.5" up from tail
Rear side boxs 1.25" in from rail rear of box 8.25" up from tail
Mid side boxs 1.25" in from rail rear of box 13.25" up from tail
front side boxs 1.25" in from rail rear of box 18.00" up from tail
the rear and mid side boxs will be the quad set up
heres a sneek peek
ProboxLarry will be sending me the front conard fins for the Twinzer Quad fin set up that will be on this board
Quote:
Hi, folks. I was bored on Sunday, so I just started hacking away at some foam. Wound up with this 5’8" retro biscuit thingy (yes, that’s the technical term). I didn’t actually measure much anything when I shaped it, so I’ll head back to the workshop and get some numbers as soon as I get a chance, but in the meantime, does anyone have suggestions on placement for a ProBox fin system ???
Hi soulstice, Glade to see you are pulling out the tools to create magic. I would go with Kensurf middle and rear ProBox placement. With the center box in the same place has kens also. If you move the center box up more, move the Quad cluster up the same. Looking forward to some pics. Mahalo, Larry
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Do you have a picture?
I am making a similar type of board, I think (round tail, speed-dialer type board), and I am going to put 4 or 5 proboxes in. Still debating on the fin placement.
obproud, Looking forward to some pics when your board is done. Mahalo, Larry
Ken, Nice colors on that board. Mahalo, Larry
Larry
those red fins set it off
thanks
What is the effect of moving the fin cluster up to 13.25" and 8.25". The boards that I have made and ridden have had the fins closer to 11" and 5.5".
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What is the effect of moving the fin cluster up to 13.25" and 8.25". The boards that I have made and ridden have had the fins closer to 11" and 5.5".
Hi obproud, There is a couple of reasons Kensurf Quad cluster is where it is on this board design. I set the quad cluster to work with the 10" fin channel first, This allows Ken to start with a 2 Plus one set up with the center channel. Then the second set of boxes are set 3/4" to 1" behind the front set-up to go to a Quad or Twinzer. With this board of Kensurf he is playing with a Quad Twinzer experiment which is why we added the extra front set of boxes.
I have experienced the Quad set up alone in this placement to have a looser feel and easier to ride backside and recover quickly coming out of a cutback without loosing drive which can be control by cant adjustment on the rear fins.
Hope this helps you with the set-up concept Kensurf is experimenting with on this board in the post here.
Mahalo,Larry
larry - thank you for explaining the layout of the fins. i have three more questions regarding the layout if you have time.
i have shaped a similar board that is 5’4’’ and will be using a center fin box and a quad set up.
1. - do you recommend that i keep the quad set up at the same distance from the tail or shorten it ( i was thinking 8'' and 13'')
2. - are the rear set of fins set with the same toe-in as the front or are they parallel to the stringer?
3. - what cant do recommend for the rear set of fins?
thanks for your time larry, and your willingness to share your knowledge with all of us here.
brasco
Ken,
Just curious about the size and foil on the fins you’re using and how they work…
Would assume single foil on the fronts and the rears???single or double?
Sizes?
It seems it can all be critical with a quad’s performance.
Nice lam, like the colors.
Pete
Pete
Im not sure exactly the sizes
I will measure them later front and back are sngle foil
PB Larry may pipe in before I get to it
Thanks for the complements
Quote:
larry - thank you for explaining the layout of the fins. i have three more questions regarding the layout if you have time.
i have shaped a similar board that is 5’4’’ and will be using a center fin box and a quad set up.
- do you recommend that i keep the quad set up at the same distance from the tail or shorten it ( i was thinking 8’’ and 13’')
- are the rear set of fins set with the same toe-in as the front or are they parallel to the stringer?
- what cant do recommend for the rear set of fins?
thanks for your time larry, and your willingness to share your knowledge with all of us here.
brasco
Hi brasco, Thank you for sharing your thoughts, good questions.
Answer to #1; Leaving the placements the same distance wouldn,t bother things to much because the for and aft adjustablity in the ProBox would make up for that. Rule of thumb you would move the set-up alittle back on a shorter board, but that also has alot to do with outline of tail. Fuller tail back and narrower tail forward. In moving your cluster back 1/2" also move your center box back 1/2". Another thing to remember is that a fin with more rake can sometimes correct the problem if boxes are to far forward.
Answer to #2; Rear fins are set at the same toe-in has the fronts. Because I have found having the rear fins parallel to the stinger causes the board to ride off the tail and be alittle stiff
for alot of people’s liking, which can also make the board harder to ride backside.
Answer to #3; 4 degree insert seems to be the most used for the rear box in Southern Calif.
Hopes this helps you find that magic spot brasco, Thank you for your support. Mahalo,Larry
Quote:
Ken,
Just curious about the size and foil on the fins you’re using and how they work…
Would assume single foil on the fronts and the rears???single or double?
Sizes?
It seems it can all be critical with a quad’s performance.
Nice lam, like the colors.
Pete
Hi Pete, I can help Ken out with your question. The front fins of the Quad are 4 1/2" tall with 80/20 foil. Back fins are 3 3/4" tall with 80/20 foil. Quads I have learned in the last 2 1/2 years from close to 100 retro fits on different boards are pretty sensitive and adjustabilty is key to finding that sweet spot.
Hope you don’t mind me stepping in Ken! Mahalo, Larry
larry
thanks again for all your advice. a follow up question about the toe-in, if i may.
when you say the toe-in is the same, do you mean that you put the same amount of toe-in (ie 1/16th, 1/8th, etc) or have the rear set of fins point to same spot from the nose as the front set of fins?
brasco
hi Larry, what would you recommend for placement on a wide tailed 6’6" board,
quad proboxes and a center FU box? here is the thread if you would like to check
it out…
[quote="$1"]
Quote:
larry - thank you for explaining the layout of the fins. i have three more questions regarding the layout if you have time.
i have shaped a similar board that is 5'4'' and will be using a center fin box and a quad set up.
1. - do you recommend that i keep the quad set up at the same distance from the tail or shorten it ( i was thinking 8'' and 13'')
2. - are the rear set of fins set with the same toe-in as the front or are they parallel to the stringer?
3. - what cant do recommend for the rear set of fins?thanks for your time larry, and your willingness to share your knowledge with all of us here.
brasco
Hi brasco, Thank you for sharing your thoughts, good questions.
Answer to #1; Leaving the placements the same distance wouldn,t bother things to much because the for and aft adjustablity in the ProBox would make up for that. Rule of thumb you would move the set-up alittle back on a shorter board, but that also has alot to do with outline of tail. Fuller tail back and narrower tail forward. In moving your cluster back 1/2" also move your center box back 1/2". Another thing to remember is that a fin with more rake can sometimes correct the problem if boxes are to far forward.
Answer to #2; Rear fins are set at the same toe-in has the fronts. Because I have found having the rear fins parallel to the stinger causes the board to ride off the tail and be alittle stiff
for alot of people's liking, which can also make the board harder to ride backside.
Answer to #3; 4 degree insert seems to be the most used for the rear box in Southern Calif.
Hopes this helps you find that magic spot brasco, Thank you for your support. Mahalo,Larry
[/quote]
Don't mean to hijack this thread, but there some question I have to ask
Hello Larry,
The board I am making is a 6'6"x20"x2.5" round pin, quad, flat bottom.
I was given some dimensions by someone whom will remain nameless, but he seems to have lots experience in this design or use of his theory.
Anyways after calculating his dimensions it came out to be 30.857" past the nose of the board. To me this number sounds extreme, but supposedly he has made boards using this formula. Both front and rear fin toe in is based on the 30.857" dimension. The front fins will be set at 11.3125" from the tail and 1" off the rail, and the rear fins are 5.3125" from the tail and 1.9375" off the rail. If you need more info, post your question and I'll try and respond to them to the best of my ability.
What are your thoughts on this ???
Thanks, Skip ....
Hello Skip ,
My real job has nothing to with surfing. I'm just a bule collar guy who works with engineers and their numbers and drawings. We build some really awesome stuff....
Think about how thick my pencil line is......Think about my ruler marked every 1/16 inch....I love to glass surfboards and install fins.....I can't work with your numbers.....my tools are too low tech....care to round off some of that stuff.....ever tried to measure off the rail ???
30.857" .....
11.3125" from the tail....
the rear fins are 5.3125" from the tail and 1.9375" off the rail.
I can do the math and round off your numbers. My pencil and your round rail will do the rest........
It's a surfboard.....
[quote="$1"]
Hello Skip ,
My real job has nothing to with surfing. I'm just a bule collar guy who works with engineers and their numbers and drawings. We build some really awesome stuff....
Think about how thick my pencil line is......Think about my ruler marked every 1/16 inch....I love to glass surfboards and install fins.....I can't work with your numbers.....my tools are too low tech....care to round off some of that stuff.....ever tried to measure off the rail ???
30.857" .....
11.3125" from the tail....
the rear fins are and 5.3125" from the tail 1.9375" off the rail.
I can do the math and round off your numbers. My pencil and your round rail will do the rest........
It's a surfboard.....
[/quote]
Sorry to have confused you. Let me try this.
30.857" is close enough to 30 7/8ths. It's actually closer to 55/64ths (.8594) but I'm not worried about .015" which is approximately 1/64th.
11.3125" is 11 5/16ths. This is the measurement of the front fins from the tail and 1" in from the rail.
5.3125" is 5 5/16ths. This is the measurement of the rear fins from the tail.
1.9375" is 1 15/16ths. This is the distance of the rear fins in from the rail.
I put them in decimal equivalents because it easier for me to understand.
Thanks for the jab.....
Your board is going to fly!!!
Test riding two new longboards in the morning... one 9'3" and one 8'8"...It's been a good week!
See ya out in the water
Stingray