Comparison of my flat water unlimiteds

[TallDude]

I recently picked up a Richmond 18'-8" x 24" unlimited flat water race board. I modeled my own 18 x 25 after a variety unlimiteds, but the goal was to get the volume down, and eliminate excessive windage. If you've ever paddled an unlimited in quartered wind you'll know exactly what I'm talking about. Even a rudder won't save you. I have paddled an old custom Infinity unlimited with a mid-6" steerable keel fin and that helped a lot. My 18 x 25 is stealthy in quartered wind. In fact I haven't had to struggle with quartered wind in any race or distance paddle since I made it.
I paddled the Richmond yesterday after I repaired the nose and tail. I'll post the quickie repair on Shape Shack. The Richmond has a rounder bottom and is felt wobbley. The recessed deck helps, so I didn't have a problem paddling it in flat water. When it rolls past a certain point the foot steering is excessive, but manageable. All and all, they felt similar in speed and glide. Mine 18 x 25 is a little heavier (I will weigh them) and seems to glide better, but probably takes more energy to get it there. I will GPS them both to see if there is any quantifiable speed differences.
Here is a photo comparison of the two boards.

[SUPflorida]

Your Richmond looks very " surfski-ish" .....

[FloridaWindSUP]

Those are both awesome looking boards. The Richmond looks like it has enough rocker for some bumps, maybe? Your blue one definitely looks more stable with the flatter bottom. Fin placement differences are interesting, too. Any effect of the fin placement that you can tell?

[TallDude]

The Richmond definitely has some Surfski genes. The rounded rails particularly at the nose and tails allow the board to fit nicely in the troughs in the open ocean. On flat water though, they cause the board to excessively foot steer. If you add a couple of chines or square the rails up that goes away. (See the picture of the how the foil increases once the Richmond rolls on edge compared to my 18 with the more squared rails.
 Both of these boards are too narrow for me to open ocean paddle. Specially because they go point to point. I've had a number of discussions with Craig Richmond about this. I had an older unlimited that I shaped for open ocean. I carried the width further back towards the tail. The board was slow, heavy, and had way too much volume. (see the picture of my old open ocean unlimited. Craig said he tried wider tails on the unlimiteds, but they didn't work well and tended to be slower. For me at 240 lbs, he recommended keeping the volume and rounded narrow tail like his board that I have. Then go up to around 26" wide and 20' in length for an open ocean board. Plus add the chines with the beveled rail edge. For flat water the 24" width is fine for me.
As for the fin placement, my 18 x 25 with the fin closer to the tail, definitely paddles straighter. The fin the came on the Richmond is a little smaller. So I'm going to swap fins and see if that helps. 

[Eagle]

"For me at 240 lbs, he recommended keeping the volume and rounded narrow tail like his board that I have. Then go up to around 26" wide and 20' in length for an open ocean board. Plus add the chines with the beveled rail edge."

First thing I thought was wow.  That Richmond looks kinda tippy round out back vs your custom for ocean use.  But for flat that 24 should be ok.  Should be nice to switch them out.  The open ocean UL design sounds about right. 

[PonoBill]

Interesting that they are both continuous curve in plan form. The lowest form friction shape is a straight line. To me an unlimited needs to do three things to be fast. First, limit form friction. It's going to have more surface area, so you need to take advantage of the length to minimize curves. I'd have a lot of straight rail tapering to squash tail. Just seems like the thing to do. If the paddler can't overcome form friction they can't go fast enough to take advantage of the good stuff. Which brings us to: Keep the waterline in the water. The value of long boards is in moving the point for wave drag up in speed. If you don't get the entire length in the water then this doesn't happen. So flat rocker, or at the least, rocker that dips the full length when you roll to one side. And finally: Stability. Chines cost nearly nothing, Sharp rails reduce surface friction. A good combination of these elements yields a board you can paddle continuously on one side or the other.

I haven't built a board yet, but when I do, that's what it will do.

[IslandFox]

I wonder just how different yours paddles vs mine.
My Richmond has the chines and double concave.

[Pierre]

looking awesome

for steering ability  in side winds i fit a centerboard (removable) aboutt 1,5 ft ahead of my standing position, it gives stability, allow steering in all conditions (excepted down winding) and improves maneuverability.

[TallDude]

I wonder just how different yours paddles vs mine.
My Richmond has the chines and double concave.

IslandFox, thank you for posting those pictures.  I was going to take a better picture of the bottom of Thomas's newest Richmond but lately he's always paddling his OC-1. You have one of the more recent shapes. Thomas says he likes that chined bottom for stability and tracking better than his older Richmond. I put a bigger, heavier fin that was on my 18 x 25 on the Richmond and did 8 miles on it this evening. It definitely help reduce the wobble. It was noticeably more stable. 

As far as speed (based on my GPS), it looks like the Richmond is just a hair faster than my 18' x 25 UL. It's interesting how smooth the pace lines on my GPS look when I'm paddling my slightly heavier 18 x 25. It may be due to the weight or the board shape has better glide? Or both?

[TallDude]

This past weekend I raced the Richmond in a 20K, and my friend raced my 18' x25 custom in a 10K. Let me just say, I'm still recovering. 20 to 25 mph steady quartered wind, capping side chop on a tippy 24" wide board with rounded rails. 2/3 of the race was pure survival. The Richmond was the wrong board choice. The wind blowing at 6:30 am should have been enough of a tell tail, but I was too set on charging with my new unlimited. The wind blows from a narrow valley at the dam on the west end and blows east the length of the lake. The valley where the lake sits widens out quite a bit. Aside from dead center of the lake, the wind peals off towards the shore on both sides. We were required to stay along the perimeter of the lake, between the 5 mph buoys, and the shore (75' to 100'). This meant paddle right side for almost the entire 3:13 minutes it took me to grind it out. Never missing a stroke or I would go backwards. Bracing every other strokes as the caps broke sideways over my board. A lot of sole searching, and a little swimming. The only paddlers behind me were on their knees. A bunch threw in the towel after an hour or less of struggling.
There were moments of direct headwind, where I could paddle on my left side for a bit. That was nice. My knees started giving out after about 2 and a half hours. I popped two shot cubes, and my knees came back. Around the 3rd hour my feet were completely numb. I was have trouble seeing because the wind and the 7000 ft altitude had dried my eyes out. There was no reprieve. Blinking did nothing.  The shot cubes were a little sticky from falling in the water, so when I popped them in my mouth the goo got on my hands and made the paddle sticky. Finally, the last 1/4 of the race was a downwind. I was so trashed, that it was really more a break, than feeling how fun it was. Now the Richmond shined. The foot steering (counter steering) that the rounded rails provide, which I normally dislike, was allowing me to steer from bump to bump. The glide was amazing. I didn't have to paddle hardly at all, and actually passed a few racing kayaks ahead of me. I finished upright and that's about all I was hoping for at that point.
My friend, on the other hand, led the 10k race the whole way. A guy who was drafting him upwind to the finish, passed him at the very end and my friend took second. He said my 18' x 25 custom unlimited was great in the side chop, and he never felt the wind pushing the board around. He said it downwinded nice, but didn't steer well as far as bump to bump. It just goes straight. In fact he said the board paddles almost perfectly straight even when it's over on a rail. Next time I feel any wind, and there's a chance of side chop, I won't be racing the Richmond.