I am thinking about getting a stand up paddle board with a mast base fitting with a view to using it in the waves as both a sail board and sup. I would like to go as short as possible (about 9' 6"), but the sailing conditions would be small surf with 13-18 knots of wind, about 45 degrees ONSHORE, and my limited experience with sailing sup boards is that even longer wave sups do not go upwind well. Is there any particular wave sup that sails well upwind, or would changes such as a bigger fin, a particular sail, etc help ?
I can't comment on other brands so I have nothing to compare against but I have the 10' RRD Wasup and I am very happy with it. I use it in small waves, as flat water cruiser and as a windsurfer. It is a thruster setup and I have no problems going upwind. I use a 5.3 or 5.7 as the largest sail. I prefer manoeuvrability over power when using the SUP.
I have the starboard 11-2 and use it to windSUP quite a bit. I find it goes upwind unreal, the long waterline and the fin set up work well. I use a 6.5 a lot of the time and drop down to a 5.8 a bit. I reckon it's huge fun. It won't go upwind like a race board though.
I have a tabou sup that im happy with seems to paddle well and windsurf in small waves good to. I have the 10''2 180L Thruster.
Here's a vid of a day we had a month or so ago there's a tabou an rrd and a starboard on the water plus a ahd
Honestly aren't they the best fun, show up with a paddle and a sail and your pretty much covered for the day.
I picked up a Fanatic Allwave 8'10'' with the intent of spending more time in the surf, however I havent had a chance to really give it a run in the surf. But is does fee really loose compared to my fanatic fly 10'. Some pics below and some comments in the SUP section link below.
To be honest SUPs do go up wind all too well. You can improve them with a bigger staigter fin but then you would be giving away manouverability. However you can rail it to give you more upwind drive.
www.seabreeze.com.au/forums/Stand-Up-Paddle/Review/New-Fanatic-Allwave-great-allrounder/
At the risk of sounding like a fanboy Fanatic are doing great things with the look of all there gear.
I think if you want a big wave board there are better option but if you want a wave sailable SUP then the new Allwave is a very good option.
I remember one session I had in Geroa, it was 5-10 knots and I was trying to get through the wash on my 94L FSW. Barely moving I just kept getting smashed in the breakers. After a lot of frustration and a few bruises I got the SUP out and it was a 'breeze'. Glide out over the white wash, a few pumps on the way back and your on the wave.
Another thing to look out for on the SUP is the mast track mounting point. I tried an oder Naish SUP and the mast base was too far forward. OK for flat water but in the surf it was difficult to get on the the back of the board so you could engage the rails. Even with my 90 kegs I couldn't carve the thing if i was standing in a typical sailing position.
If you notice the two boards in the PIC, the fly has 2 mast points, the front one is useless for surf. But on the new Allwave its well positioned and the board just spins around nicely. I had my doubts about this board because it is so wide, but even in big bay swell it is very fluid and manouverable. Hope to get down to Gerroa for a session very soon. 
BTW I'm 90kg and not an exprienced SUPer, but his board is very stable (very wide). Unless you're well over a 100kg then I wouldn't consider a 9'6" in this model. Another similar option is the Starboard Widepoint, like the fanatic its a short, fat surf oriented board.
interestingly my chopper 90 has sup like drive (the Drive of a small SUP anyway) on a wave in light wind
- it actually creates its own drive out of the wave - which is a first for me on a windsurf board.
Can ride down the line with no power and just hold the boom with 1 hand while i line up the reo section
(i ride a SB 10'5 drive when i am Supping with a paddle)
I use the 11-2 starboard I tend to SUP more then anything nowadays. I just love the glide of a longer board. I also longboard surf so it just fits the bill for me. I agree with not putting the mast track forward even in flat water. I sit around 95-100kg so I don't lack the bulk to engage the rail at all
Is there any scenario where a SUP is better than a big waveboard for sailing waves in light wind?
I only ask because I've been out at Gerroa on an 82L, not struggling, while others were on SUPs.. I didn't get it, and figured if I got any fatter, a 90-120L waveboard would do everything a sup would do, and more..
Another thought, SUPs don't plane, or at least not very well, so why not make a large volume, dedicated wave board that is not designed to plane?.. I recall Kauli was sailing a non-plane-able waveboard at Cabo Verde*..
Basically the question is, would a dedicated high volume, non-planing waveboard look any different from the crossover SUPs with a mast track???
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*Kaulis board did plane on the wave, of course.. That shows standard waveboards are a compromise between a rocker that works on flat water, and a rocker that works on bent water (wave face)..
I've had my 12x32 *board big easy out the past couple of days with a 6.2 up. 5 to 20 knots gusty.
Just like sailing the old wally, brought back the memories of all those years ago.
12 foot of heft gives you plenty of momentum to punch out through the break and there is no problems in the lulls, you can just stand there.
Handled the sail pretty well I thought and tracked up wind well, once over 10 knots.
On the wave, the heavy rocker of the big easy helps to manoevre.
I did notice that it is better to not be planing with too much speed on entry to the wave - otherwise the dynamics go a bit awry. Better to be travelling at the wave's speed, so that the board naturally 'surfs' as it would if it were a SUP. Much more manoevrable on the wave at that speed, and the sail seems to be less in the way.
SUP sailing is really not like short board sailing at all. Its the same as longboard surfing and short board surfing are different. Longboarders are after the glide and the cruise that comes with a 9 ft plus board (talking surfing here)
I don't think most short board sailors would especially enjoy windSUPing in the surf, the idea of being able to move around the board, no straps and just walking the board is cool no doubt. I have had a couple of small wave days now and being able to hang five on a board with a sail is pretty cool. The other thing is that you actually don't want to go fast, just fast enough to get on the wave like if you were paddling on.
I also don't know if I would be taking the SUP out in surf that had any size to it, I reckon the mast and boom would prove short work to the SUP if you were wiped out on a wave.
I used my SUP (Fanatic Fly 10' 160 litres) yesterday in mushy waves at Umina with a 5.9 wave sail. Managed to catch a few rollers and had a good 2 hours sailing, but unless you had a large wave board (over 120 litres) then it was not a great wave sailing day.
I use the SUP as a paddle board and it is good for that both on flat water and small waves, but on marginal wind days I take it and my 90 litre freewave Mistral Naish to the beach. If it gets windy, the SUP stays out of the water. really windy, then the 80 litre gets a run.
A few weeks ago I used the SUP for 1 1/2 hours paddling in the waves, then a southerly came through and I went out on the 90L for 2 more hours. Sweet.
I don't think I need a large volume wave board. 
I just read Barns post a bit more and I am agreeing with him on this that a non planning large wave board would be good to have. The only problem I see it that most people that are SUPing would say why should I have both when the SUP will do pretty much everything I need anyway. I think it would come down to pure economics. 1 SUP = $1800 1 wave board = $2000 if I had to make the choice I wouldn't get both it would only be the SUP and pocket the remaining $2k to do other thing with.
yea they actually aren't built to be knocked around really. If someone really wanted a crossover board (i.e. light wind wave board and SUP (kinda)) they could try the Exocet longboard at 11-2 its actually really not bad to sail. I had the 10-5 for a while. The downside is they are bloody heavy. Although having said that heavy longboards give great glide.
