The photo looks like it's rough, but the surface is actually very smooth. It nevertheless needs sanding, The 'seam' for the external perimeters is appearing as a raised ridge along one side of the leading edge.
This is the first Wanderfalke fin with Eppler 168 foil.
295g including the support system. The version with the concave foil weights about 274g with supports. So there must be around 20ml of concave.
This one will probably be a good candidate for less than 100% infill 3D printing, because it uses so much filament.
Great work, you know you're going to end up starting a fin business ?
I just put a longboard box (inappropriately) into a mini simmons just to test fins like this. I can see you've gone a long way in testing now, great!
I'm going to print off one and try it at some point. I hope I can keep up with you though as no sooner as I download a design you're onto the next! Such is the speed of development!
Do you simply test by moving through water and feeling the resistance or are you riding with them? We're still in summertime flat here
But I'm not getting anywhere near as much surf time as I would like at the moment. That will hopefully change again.
So far, the main difficulties were related to learning 3D printing and OpenScad designing, and trouble-shooting 3d printer problems.
I have toyed with the idea to print fins with a handle instead of a fin base, but that's stupid as I just realised. Thanks for asking, now I have a much better idea:
I might design and 3D print a handle that attaches to the UTFB in a non-destructive way, maybe even long enough so the hand holding the fin does not have to enter the water.
However, I'm not convinced that will be very useful for testing.
However.......if combined with repeatable water flow conditions, it might be feasible. I have a 2 person Kayak. If I attach an electric motor to it, I could use a lake on calm mornings to test fins in laminar water flow of fairly consistent speed. I would just need a device to measure torque and lift somehow.
But the results from 'organically' designing the fins by arranging tubercles so that they look right to me have been very promising anyway. I think I'll stick with that and hand the resulting fins to good surfers for testing. And eventually I hope to get more surf time myself again.
Third time 'lucky'.
The new elliptical support pad system worked very well.
It is only one gram lighter than the old system but more effective and gentler on the print bed.
Any idea what tubercles would do to a rail fin, such as fins with 1 flat side and 1 foiled side?
Send me your dinged, damaged, and yellowed.
I don't know what tubercles would do on a fin with a flat side.
I think fins should not have a flat side in the first place, but I only surf single fin boards since several years now and don't miss the extra fins one bit.
The printer is humming along nicely for once, and I'm managing to crank out a 3D fin print per day. But I'm not keeping up with the post-printing work of finishing them nicely.
Anyway, the aim for now is to get a set of fins to a few surfers so their performance can be compared. Once there is more clarity about what amplitude, frequency and number of tubercles works best, I can proceed to improve the construction of the fins with the best shape(s).
For now, printing solidly from transparent PLA for prototyping seems appropriate. Later on, other materials (possibly a mix of materials) can be used to print proven fin shapes lighter and stronger than the PLA solid variants.
Looks like the UTFB is a bit too 'Universal' when I try to incorporate too many features into the same Universal Tough Fin Base.
Although easily converted to a standard screw-and-plate type fintab, the presence of the Ball Spring Plunger (BSP) holes and the extra aft hole for the swivel string make the area around the aft pin too weak.
The photo shows 2 fins that snapped off while wrcsixeight was trying to remove them from the fin box after they had been in for a while. He is repairing them so he can use them again.
So I am 3D printing a few fins for wrcsixeight that do not have the swivel hole or the BSP holes, and the front has the cutout for the plate and screw already removed. He will drill holes for the BSPs exactly where he needs them in his finbox.
I have some ideas bouncing around for making a better snap-in system to hold the fins firm enough, but release them in an impact. Until that is ready, I'll 3D print the fins with either snap-in and swivel-rope-hole, OR for screw and plate. It should be a bit stronger that way. Eventually the aft pin is not going to be required.
I've added a base from another fin here to make a stl. I haven't tried printing it. Boolean join failed so I just used 'combine' in meshmixer
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