Laser finplacer garagestyle

Hello friends!

I’ve found it hard to line up my fins in a good way to get the toe in accurately. This can ofcourse be done by using some form of long ruler but it can be a difficult to do on your own especially on boards with lots of rocker. I came up with this idea yesterday wich I think is a great way to do it. Pictures will hopefully explain. What I use to get the laser mark is a carpenter tool -DeWalt self leveling line laser. Comes for around 100 bucks but i think there are more cheap ones out there. To get a toe in angle wich intersects past the tip of my board I had to extend the stringer to have something outside the nose of the board to line up with. In these pictures i line up my fins to intersect at 2" past the nose of the board with trailing edge of fin at 8.5" from tip of tail and 1.25" in from rail. I think i will use something like 5 degrees canting on these but the toe in angle looks a bit to much at 2" past the nose as shown in the pictures. How far outside the nose could I go, anyone? This is a 5’10 medium rocker twinfish. Any ideas or guidelines? Getting close with this board and i dont want to make a big mistake now.

 

Cheers


Pictures didn't upload?


Nice one, multiple fin alignments gave me fits last time. There was also the stringerless lost centerline problem constantlly showing up, for next time I've put a swap meet lazer tape measure/level in the rafters looking down onto the racks, same deal you've done, slight problem is getting it up high enouph to project full length of board nose to tail. The nose and tail will get hack saw slices to permanenty mark the templated end positions so they can't be sanded out. Another slight prob is getting the lazer to shine brightly enough thru ambient light, my cheapo model needs very subdued light to be well defined onto the board. The fin placement idea is great, thank you.

This is a great idea, why didn’t I think of it…

If your laser comes with the red goggles, use them. They make the beam a lot easier to see. I had the same problem on my last construction job - could not see the beam in sunlight, put the goggles on and it was much better…

I guess you could sight up the laser to run down the center of the board and make some temporary stringer markings on a stringerless board. A stringer is always good to have to make meassures from. I've read a ton of threads about fin placement and meassurements and a common thing that people do is meassure out a point on the board where they want their trailing edge of the fin to be and then go up to the leading edge of the fin and meassure so the leading edge of the fin is for example 1/4" closer to the stringer. This seems to be a fairly common meassurement but you loose all sense of angle because fins have different lenght of base. This is why it is better to make a pencil mark where you want your trailing edge of fin to be and then take a long ruler, or a laser like i've done, and align the trailing edge of fin mark with a point somewhere around the nose of the board. This is a question of taste and this is where i'm stuck right now.

 I know there are different lasers out there with varying quality. I bought this one because i do some carpeting work and it's really good to work with even though there are some ambient light. Even works outside on a sunny day if you use it with the red goggles, good one bartt! Didn't understand what you meant with hanging your laser up in the rafters. I do it like the illustration here. The laser emitts a line, or actually a wall of light, that spreads like in the illustration. Therefore you can simply place it on a tripod or similar a coupple of feet infront of the board and one or two feet above. The laser will emit a line along the full curve of the boards bottom.

Hadn't thought of trying the lazer off end of board, sounds easier than overhead mounted in the rafters. First try was shining lazer onto floor, improved try was high mount shining straight down onto racks, worked, went with it. Its too high up, need a stick to hit on/off switch.

hey Guys,

i really like this idea, i just want to suggest that you should really look at our adjustable fin system, if u haven't seen it: www.4wfs.com

it really helps, because  you can adjust  your toe-in, up and down and splay angle settings with 4ways, however,  it's always been a hassle to know exactly how much toe-in or out one has...

either way, it supa critical to water-flow and the boards' performance, and since every board is different it's a major asset to have...

thanks for this topic....i find it very interesting....

cheers

deano

 

 

 

 

this one has worked well for me past 3 years, throws a dot or a line, the little plastic feet slide off and you’re left with a nice flat & square ruler with a laser & level bubbles. perfect to draw out side fin lines. put the nose against the wall at the plumb line, line up the laser along the stringer at the tail, then move the tail of the board until the light lines up with the line on the wall. then I line up the laser along my back fin mark, watching the light on the wall, using the plumb line as a guide for distance from nose.

 

That seems like a great way to do it. Easy and accurate. With the kind of laser I got I have to take a ruler and line it up with the beam from the laser and make a pencil mark on the board. Guess you can just line it up and then make a mark against the ruler. 

What distance from nose do you use if I dare ask? I'm doing a twinfish as you can see in the pictures above but it's not a oldschool keel twin. My board has some more rocker than otherwise quite flat fishes out there and I use fins that i have designed myself based on the fcs MR template, adding more rake in the trailing edge and I use a little different foil, more like the fcs K-fins has. From the looks of it i'm going to go one feet past the nose or maybe even more. What do you think about this?

Hi bramberg, 2 1/2 " off the nose (at 90 degrees to the stringer line from the nose tip) has worked well for me on a 5'10 twin/ quad semi fish. No lasers here just a long bit of 1mm thick steel flat about an inch wide. Line it up with the fin dot and then measure out from the nose tip. Hope that helps

 

Yes that's close to what I have the toe in right now. Fins are glued to the board but i'm eyeballing it a little longer before glassing them on. Think what's so confusing about fin placement is that there's alot of ways to meassure and when you get a meassure from someone you first gotta convert it to your own way of meassuring to be able to compare. I understand how you meassure toe and it's a good way i think. Someone gave me the suggestion that 8.5" from tip of tail was way to much and that i should go for something like 5.5 instead. I never understood the way it was meassured though. These are meassurements off my board now wich i would call 8.5". Then it could be called 6" by someone eh.. 

we always reference as from the shapers rear back dot (ie: rear back tip at the base of the fin)

not the raked tip, as this varies from fin to fin...

depending on your fin outline 8.5 doesn't sound far off...

 

regards

deano