Hobie Forums http://www.hobie.com/au/en/forums/ |
|
EPO rudders, is it legal to copy them? http://www.hobie.com/au/en/forums/viewtopic.php?f=9&t=11709 |
Page 1 of 1 |
Author: | Karl Brogger [ Tue Feb 03, 2009 10:42 am ] |
Post subject: | EPO rudders, is it legal to copy them? |
A few months ago I was asked if I could make wooden rudders. Building one set by hand would be expensive. Probably along the same cost as the EPO's, if not more. With a bit of poking around I think I may have found a small CNC that I could pretty easily produce rudders quickly, efficiently, and more importantly consistantly. People love the EPO shape, and I would have the capacity to make an exact duplicate of the shape, only in wood. They've got some nifty 3D scanners for duplicating mouldings, for repairing/restoring. I'm assuming that I'd be able to copy the foil shape with it. My question is probably above all tuned to Matt Miller, would I be in a world of trouble for not using an original design, and profiting from it? I don't want to step on any toes, or more importantly get sued. 2nd: is there a real interest in this? Start up cost's are pretty low. It is a small machine, and this technology has gotten pretty reasonably priced. At the same time, I don't want to spend the money and sell three sets of rudders. Granted I could use the equipment for other things, but its not something that is real high on my list of equipment purchases as far as my regular wood working needs go. |
Author: | MBounds [ Tue Feb 03, 2009 12:11 pm ] |
Post subject: | |
From a strictly technical standpoint (I'll let Matt M. address the copyright / trademark issues), wood is not the best choice for rudders, for a variety of reasons. From a racing standpoint, the only boats allowed to have aftermarket rudders are the 14 and 16 (see the class rules for the parameters involved). And unless you make them out of balsa, you're not going to get lighter than the carbon EPO's, so that pretty much eliminates the racing market. If you're looking to sell to the recreational market, you can start with a 1" thick (that's the max thickness) marine plywood blank and go from there. You'd need to epoxy it, maybe glass it to protect it from the water. Also need to sleeve the bolt holes to keep them from wallowing out. They'd be pretty heavy. A "back of the napkin" estimate puts the weight at about 7 lbs. You might be able to produce a reasonable blade for $150 each. The stadard nylon blade is $132 from Hobie. They would sure look cool. The Brazilians have been using wooden rudders for years - they're like pieces of furniture. |
Author: | Sail Revolution [ Tue Feb 03, 2009 12:20 pm ] |
Post subject: | |
MBounds wrote: And unless you make them out of balsa, you're not going to get lighter than the carbon EPO's, so that pretty much eliminates the racing market.
I think that there is a minimum weight for rudders in the class rules. Something like that rings a bell. There was some issue with the Euro EPO's (with the gray logos) being on the light side. I could be totally mistaken and fabricating this whole thing. ![]() |
Author: | mmiller [ Tue Feb 03, 2009 12:23 pm ] |
Post subject: | |
No Hobie Logo or Name EPO2, but you certainly can make your own. That is in the class rules. |
Author: | MBounds [ Tue Feb 03, 2009 1:57 pm ] |
Post subject: | |
From the 14 and 16 Class Rules: Quote: 1. RUDDERS AND RUDDER ASSEMBLIES 1.1 Rudder blades made of another material, yet conforming to the size, shape and minimum weight of the standard rudder blades, may be used. Rudder blades must conform within the minimum and maximum dimensions that are found within the profile plans. Profile plans are available through the IHCA. 1.2 The maximum thickness of a rudder blade(s) shall not exceed 1.015 in. (25.8 mm.), tapering over a distance of 2 ft. (60.96 cm) to a maximum thickness of 1/2 in. (12.7 mm), 2 in. (50.8 mm) from the bottom tip of the rudder. These dimensions are for reference purposes only. Please refer to profile plans for exact dimensions. Profile plans are available through the IHCA. From the General Class Rules: Quote: 10.7 The minimum weight of each rudder blade shall
be 3.0 lb. (1.36kg) It would be tough to make a blade with a balsa core that weighed less than that. I have the Euro carbon rudders on my 14, and I can attest they are very light. When you un-latch them, they float up. |
Author: | Karl Brogger [ Tue Feb 03, 2009 4:19 pm ] |
Post subject: | |
So copying a shape would be ok? Or, you just couldn't do anything about it and would carry a grudge forever? ![]() ![]() I was kinda thinking a lamination of some sort, alternatating woods, maybe an inlay. It'd be all hardwood of some variety, so no, they definetly wouldn't be down at minimum weight. Seven pounds probably wouldn't be too far off the mark. Balsa would be a poor choice. I haven't worked with it since my RC plane days, but I remember it being more like styrofoam than wood. Beside, I don't want to be doing any glassing I'd bet the Brazilian ones are a mahogony of some sort. I was thinking a birch, and walnut combination. Both woods weigh about 40lbs per cubic foot. Anyone know the volume of a rudder? |
Author: | jkkartz [ Tue Feb 03, 2009 4:54 pm ] |
Post subject: | |
How about a foam core with wood veneer and reinforced with carbon? The choice of wood and paterns are endless. |
Author: | sunjammers [ Tue Feb 03, 2009 5:00 pm ] |
Post subject: | |
I had a chance to buy a set of the Brazilian blades I wish I would have, simply to hang on the wall. |
Author: | J_Eaton [ Tue Feb 03, 2009 8:59 pm ] |
Post subject: | |
Karl, howzabout birdseye maple? ![]() ![]() |
Author: | J_Eaton [ Wed Feb 04, 2009 6:51 am ] |
Post subject: | |
I've got a pair at home called Switchblades, made in Florida. They're black, don't what the core is (looks like paper!?!) but one needs work and his been drying out for a couple of years now, but it still weighs 50% more than the other, "good" one. ![]() here's another "knock-off" |
Author: | Karl Brogger [ Wed Feb 04, 2009 3:48 pm ] |
Post subject: | |
I had a set of those on my first H16, not counting their massive weight they were really good rudders. I didn't really know what crappy rudder was until I bought my H14, which got a set of EPO's and newer castings off my 06' H16 about a month after I got it. Maple weighs 35-44 lbs/ cubic foot, according to my reference's. I'd have to imagine birds eye would be on the upper end of that spectrum, as the grain is so dense. Spendy too. About 3x's or more than that of regular maple. Which isn't really a big deal, there isn't that much material there. |
Page 1 of 1 | All times are UTC - 8 hours [ DST ] |
Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |