I have a question regarding my next project. I am planning to build a hollow balsa eagle glider. Based on pictures of Skip Frye, Tyler Warren and Ryan Burch (eagle) gliders, and based on stories on this forum i have set up a preliminary design plan. I’m pretty satisfied with the outline of the board but i am still a little bit uncertain about the the bottom contours and the rocker profile. Bottom contours are based on what I read on this forum: Belly/rolled bottom to vee. I have attached an image of the design, I am really curious about what you think about it.
General info on the board:
12’ long
23 1/2" wide
3 3/4" thick
Rocker @ nose: 5"
Rocker @ tail: 3,5"
I divided the board into 20 sections, which will later become the rib spacing for the board.
I have seen pics of Skip’s gliders that have heavy double concave out the back. I have also seen boards with solid vee in the tail. I think big boards need vee or double concave in the tail to help facilitate turning. What fin setup are you planning on using?
Thank you so much for the quick replies. Fin setup will be a single fin. Based on your advise I will incorporate the double concave in the design. Any opinions on the rolled bottom? I have no experience with rolled bottoms so I wonder if the amount of belly is too much…
I’ve owned several Frye glider type boards and none had the concaves which have been mentioned. I’ve seen photos of them but never owned one. I think your diagram looks about right for the type of board you have in mind. If I were to change anything, it might be to boost the tail rocker a bit and perhaps bump out the wide point for added outline curve. If I had a gripe about my longer glider boards it was that they could be difficult to handle on steep drops… extra curve in tail rocker and outline might save you some grief at some point(?)
My glider boards had a fair amount of bottom curve and it looks like you’ve included that in your design. I will try to include some photos I have taken from a 10 footer.
You can almost see the double concave running from the nose all the way back in this video. Also, I don’t care how old and crotchety you are, if you do what the guy sitting in the lineup does around the 1:05 mark, you’re a dick.
Thanks a lot everyone for all the valuable input! I made some minor modifications based on your comments. @Johnmellar, the pictures you sent are really helpfull. Also, I totally agree with @GregTate. I will keep you posted on the progress as soon as I have something to show.
I can’t tell you about Skip’s Eagles, but the ones I made all had 50/50 pinchy rails and soft belly from nose to tail and feedback from the owners has always been excellent. Photos are of the latest I made, 12’3" X 23 1/2" x 3 1/2":
Now that is a spear! Very nice board Balsa. Thanks for sharing. Are the rails 50-50 all the way through or is there a hard edge in tail? couldnt trell from the pic.
I am curious about blanks as well. I want to know what to by when I decide to shape a behemouth of a board for myself! Longboard or gun blank? Sorry to pester you with questions Balsa.
I have a Bing Lightweight Pintail 10-0 and the rails are very similar to what you describe. Pinched and a slight rolled bottom on the back 2/3’s ending in a Vee. Your confirmation will help me hone the one I am building.
My Kathy and I may be heading to “the Provence” later this year. I’ll ping you if we do and perhaps we can take the train over to see you and your Cathrine.
I’ve seen several boards besides the Fish Simmons that had the double concave deal. On the gliders, the front 1/2 look almost identical to a Phil Edwards Hobie… pretty much the same rocker, belly roll, and forward rails.
The back end is where they differ. The modern Frye gliders that I’ve owned or seen have a sharp down rail in the tail. It is Frye who said that “Round bottoms suck - literally!”
It is actually a bit of a curious transition from the hard down rail/flat panel-vee bottom to where the roll starts about 1/3 of the way forward. The ones with which I am familiar kind of follow the triple stringer - where the stringer meets the tail edge is about where the roll starts and the roll extends forward roughly along the stringer line. On the boards with the dual concaves, the concaves are generally placed between the stringers as well. So dual concaves inside the stringers and roll outside the stringers and generally along the stringers is the transition zone.
Here are some pics showing a Phil Edwards model and Frye glider stacked on top of each other. Also a tail rail shot of a tri-fin and of Frye in shaping room showing concaves…
