No doubt Roy is a superior craftsman and very knowledgeable.
With an open mind and a religiouosity(sp) towards touting his products and defending his claims, but rather closed and dismissive towards anything that gets in the way of the former.
This forum was created for craftsmen like him…not me!
My garage board building days were quite a while ago.
As always I welcome truly sober, fair and honest debate
in this technical based forum amongst those that are capable of doing so.
Hello MTB, thankyou for your kind words. I just thought that I should put on the record that Mike has not stopped me from posting. Mike was generous in spending some of his valuable time giving me some advice about internet discussions, and expressed a concern about the level of argument I was involved in. The decision to step back was mine. Maybe I will make a few postings next year. I Thank everyone on Swaylock’s for playing the game, and for enduring my constant barrage of posts. Perhaps I am like the army cook in the ‘Sad Sack’ comic who got a new automatic potato peeler . . it was potatoes for breakfast, lunch and dinner until they took the machine away!
I know my friend who longboards - and who is keeping the fin foiling and molding and etc. industry going by all the set-ups that he purchases in pursuit of the holy grail of trim speed - would disagree with this.
What is the best bottom shape and tail rocker for one of your finely crafted surf trimmers?
What glue do you use to bond one of these together? (Mr. Greenie Tree Sap?)
All the others are pretenders competing for the title of short board guru - major domo. Please don’t leave us hanging - finish what you started…
There has been a lot of discussion, conjecture and lively conversation in this thread, but noone else has posted any footage of really fast surfing. Come on people lets really show everyone what is fast…
Just watch any surf video. Check out footage of G-land of J-Bay for some fast sections. Here’s a clip from a local site on the east coast. Three segments from the end there is a nice right the guy gets barrelled on. Nice little burst of speed to make that section.
Kind of a moot point really, no one relates a good wave to the respective speed in a number term, it’s all subjective to the type of wave being surfed.
Have had one of those for a couple of years, but I’ve never been able to get it to work. Counts 60-cycle noise (as it should); but never propeller rpms (tried several different propellers over a wide range of rpms); propellor to pick-up spacing is less (sometimes considerably less) than the max distance given in the instructions/spec sheet. Anyone got any ideas?
Decided to follow soul’s lead and ordered a Garmin Geko 201 and Aquapac. Hope to get some readings within 2 weeks (assuming the surf cooperates).
Now if I can get the speedtech to work, I’ll have both through the water and over the bottom readings.
‘Trim is dead’ is certainly an unlikely theory. Mr Loehr qualified his assertion by saying that trim was dead in terms of ‘performance’ surfing. What he (and others of his ilk) usually mean by ‘performance surfing’ is vertical maneuver based surfing, or surfing ‘without trim’. So really it is just another meaningless circular argument used to assert the supposed supremacy of current shortboarding styles.
In reply to your question regarding tail rocker and bottom shape for the Power Surfboard, I must say that I like to keep things simple. There are some basic rules which I always follow.
1) I always make the tail rocker a perfectly even curve (a circular arc), and thus never use the accelerated tail curves or tail kicks which are often seen on boards over nine feet.
2) The apex of the tail rocker is always matched to the wide point of the board, that is, they both start at the same fore and aft position. This matches the foil characteristics of planshape and rocker, for neutral handling and smooth rail to rail transitions.
3) The fore and aft position of the apex of bottom and planshape curve is always at, or in front of the mid point of the board.
These simple rules are derived from the idea that the same rules which we apply to fin foil sections can be applied to bottom and planshape curves with good results.
Regards, Roy
PS If these rules are followed it seems that the actual amount of rocker used can vary over a wide range.
In fact while speed is fun, staying in the pocket is still high quality surfing without regard to board length. Sometimes you have to stall. What an under appreciated maneuver.
I surf boards that perform best when a more constant trim is achieved. They have a grand powerful feeling.
I also surf boards that turn on as the trim line is changed rapidly. I have few that will do both, they are my favorites. This the type of board that I hope to able to shape with some amoung of expertise someday.
Each to his own:
I have to agree with you Roy that a constant arc in the outline does make for a board that trims very well. Rocker, rail and bottom configuration also play their part in how a board trims and can’t really be taken out of the picture. Some surfers prefer to hold a trim line longer than others. Some surfers want more versatility in a board than others. It’s all relative and about style. There is no right and wrong IMHO.
I had another question also. What glue do you use? I made a guitar recently and we used plain old “Titebond” which is water based and I believe would be unsuitable for a surfboard…
Also your reply had me wondering about your perfect circle law, because when you make a guitar the wood actually tells you how much curve you can put into it. And how thick or thin affects performance as well with wood as the material of choice. So my question from that is this; Did the wood “tell” you it had to be a perfect circle or did you try accelerating tail curves and they didn’t work?
Did they counteract your tunnel fin? I am intrigued by the tunnel fin, and here is why…Whamo. They are a toy manufacturer here in the US that made a - I think it was called a Turbo Tunnel or something similar - that was just a small plastic wing shaped into a circle, any way - it defied logic cause you could “throw” this little light weight plastic thingie a good 100 yards! To me the tunnel fin is a great answer for keeping that bouyant of a material tracked in the water as well. I think that with trimming shaped rails you would need to keep the tail firmly in place or you would have to walk back and forth to weight different areas of the board, which wasn’t the case in your video presentation.
I was hoping to see your board perform on a longer wall though!! I’m ready to see the turbo tunnel effect kick in and - leaving the thrusters behind, Roy and son approach the speed of light! (video frame numbers 24 - 32)
I just saw the movie “Riding Giants” and they claimed 35 miles an hour.
It is interesting that you should mention the annular wing flying toy. We had been building and testing cruciform hydrofoil fins with mixed results, when on two occasions we found annular wing flying toys (‘The Flying Gyroscope’ ) just lying around. As you say they are extraordinary fliers. Then we saw the ‘hoopskirt’ model aircraft in ‘Popular Mechanics’ magazine and made the jump to the tunnel fin.
Regarding the natural bend of timber and the circular rocker, we didn’t ever experiment with accelerating tail rockers. I have always thought that if rocker curves follow the same principles as those applied to fin cross sections then they will always behave well. I have never seen a fin section with a trailing edge curve which accelerates as it moves aft, and I don’t think that such a curve is functional . Longboards which have lots of accelerated tail lift are built to the equivalent of a rating rule (longboard competition criteria), and such rules almost always produce craft with anomalies and distorted shapes. The natural bend of timber allows very tight curves to be bent if the timber is thin enough, so we haven’t been limited by the ability of timber to bend.
There are only two curves used in the Power surfboard: the circle and the ellipse.
Regarding glue, we use the same 4 to 1 epoxy resin for everything, but I am keen to try vegetable based epoxies, suncure resins and teak oils.
Some long walls would be nice. This area goes through cycles. We had excellent sandbanks and swells from 2000 to 2002, now the elements can’t seem to line up and produce the goods although we are still getting waves. I will see what we can do.
When a board turns, any spray which is thrown outwards during the turn is energy lost. Thus a board which could turn without spray would be the fastest because it would go through the turn more efficiently. Throwing spray is evidence of speed, but it is not an efficient thing to do in terms of speed.
If a surfer likes to throw spray because it is spectacular or feels good, then they are doing so at the expense of potential speed.
exactly-i know my comment sounded llike i was equating spray with speed-quite the opposite, as you pointed out-less spray means a more efifcient planing board which means faster…
Hello Matt, what spray were you talking about? I am interested.
Regarding speed, it is a strange paradox that sometimes some very low speeds are actually ‘high speed’ on a particular day, or on a particular section.
In yacht racing this often happens in light winds, where tons of mega expensive equipment and crew drift around a course at a couple of knots. Often these ‘drifters’ are fascinating races, and the fastest boat still wins the trophy, even if they went at walking speed.
Surfing in marginal conditions is fun, and small speed gains in such conditions can reward the surfer with a much longer ride. In conditions which are marginal because the wave is small and/or has a gentle slope, nothing can compete with a very long board.