I have used a wave boom (North platinum) on my small Koncepts (4m - 5.8) but the boom is not really wide enough for the draft to be as full as I would like.
I am after recommendations for small booms with wide arms, Ideally to fit sails with 150 - 190 boom length.
1. Carbon,
2. Needs to fit RDM mast
3. needs to have a 3 pulley back end
4. narrow grip
The choice is limited for wide small booms. Check out the chinook pro1 Carbon, their small booms are pretty wide, around 47cm/48cm. They do a 150-200 and 160-210. They list the internal width for each individual size.
AL360 E3 Carbon slalom booms are all 49cm internal width, the the shortest is 180cm. AL360 will do a cut-down version for speed sailors (I have a 180cm cut down to 170cm). They are not on the website, but they will do one on request.
x-booms do a 165cm slalom boom, internal width 49cm.
you'll need rdm adapters for all the above.
I think it would be difficult to find what you are after as booms seem to have gotten skinnier over the last few years.
It might be possible to cut down a larger boom to cover that range, which would generally leave you with a wider boom. It would take a bit of effort though in making sure the tail piece still had enough room to move.
I just had a look at one of my older chinook carbon booms and they are 170-235. The boom locks are only retained with a hole in the arm, so it seems possible that you could trim about 10cm off them without drama, and more if you also trimmed the tailpiece. It might be too complex to do though.
At home I have some of the older NP/(some other manufacturer) carbon booms that used that twist-lock setup. They seemed a bit wider than the current range, so that might be a second-hand option.
As for the 3 pulley back-end, when I first started sailing I used a triple-block ronstan pulley on one boom and they made outhauling a breeze. If you find a boom the right size, you might see if you can rig it with one of those?
All my booms are setup for SDM, but I use the Ezzy RDM mast shim, and it works perfectly.
i was going to say you might have to call up Karin Jaggi while she's still in the state to see if she has any sitting around from her Luderitz campaign ??
but it looks as though she was using the asymmetric booms from Patrik
That is exactly why I use small alloy booms for the smallest speed sails.
-They are wide if you get the right brands, or it is vey easy to cut down a longer wider one.
-They come with, or can be easily fitted with a 3 pulley rear end
-They are plently stiff at lengths I use 155 - 170cm
-They are pretty much the same weight as a short Carbon boom.
-They cost a tiny fraction of what a (wrong shape) carbon boom costs.
You could also look around for an older, wider style second hand carbon boom?
But you are right, the newer short carbon, and most of the 'teardrop' shape alloy booms are waaaay too narrow for smaller speed sails.
There are quite a few of us who sail at Sandy Point who have regularly used KA Koncept speed sails in sizes 4.0m, 4.2m, 4.3m, 4,4m and 4.6m over the years, and none us wears a dress, at least not in public.
Even Big Tony used his 4.4m on sept 27, 2009 for his 49 knots runs! Spotty was on a 5.0m for his 50!
At that time we didnt have a 4m Koncept, but us smaller guys were wishing we did have!
The modern wave and freestyle teardrop shaped boom is hopeless with these sails. Far too narrow. The older, wider shape booms are good if you can find them, and they are still around if you look hard enough, especially in Aluminium.
For me, the interesting things was that at Luderitz, even when when the wind was 40-55 knots, I could not use even the 4.6m, let alone the 4.2m. The course was far too broad that day and as soon as I was in the course, at 140+ off the wind, with the 4.6m, I was underpowered between gusts.
At Sandy Point, the run-in is longer (tight angle) before you get to 130-135 angle and the wind more laminar and constant (or at least it used to be ). It was always faster to use the smallest sail you could get full power on. That also applies here on most of the really good easterlies.
On courses where the wind is less laminar, and much more gusty, larger sails are needed. Sandy Point has become more like that now.
I have a severne enigma carbon slalom boom that goes down to 170cm . it has a three pulley back end plus a good hook and loop for quick rigging as an alterative. i used with it a reflex 5.2 at shark bay in about 40kts a few days before new year . I regularly use it with a 7.8 and its in its third season. its a great boom nice grip and stiff the rear adjustment plastic bits on the tube crack but give no problems. I keep my eyes open and havent seen anything better..
I'm crap at Diy, but it's fairly straight forward to cut a boom down. Before I got AL360's, I did cut down an old HPL Carbon race boom, ended up nice n wide.
maybe a secondhand cut down is way to go?
www.facebook.com/ptmiriam/videos/1929078784010310/
Miriam has the solution. I my self have the small North slalom boom on order for the spring. It Goes down to 170 and my smallest speedsail is 169 (5,0)
Making or fitting a wider rear helps a bit, but it has less effect towards the front, or harness line area where you need that max width to get a satisfactorily deep draught in the sail. If you start with a modern narrow front wave boom you will struggle to gain enough.
My short alloy boom is wide enough, but I have experimented with using a wider rear end from an older KA race boom. Here are the pics and measurements:
Boom set at 156cm (Edit: the rear harness strap is approx 50cm back)
Measurement is back from inside head clamp (front of mast) - width is Inside boom.
Standard Wave boom: 50cm back = 40cm, 60 back cm = 36cm.
Boom with wide rear: 50cm back = 42cm, 60cm back = 40cm
This alloy standard wave boom which is nice width anyhow. (it is a Sunshine Wave Pro, but it is identical to the older model KA Boom)
narrow and wide rear ends:
Wide end fitted:
Another view - short and fat! :
Miriam's handiwork is impressive but that looks a bit too technical for me.
I have found locally a chinook pro carbon boom 160 - 226 with a wide three pulley back end which happened to be on sale this week.
It is the widest of the short booms I could find, (similar to Daffy's sunshine boom) measuring 43 cm inside width at the back harness line. If I leave it as is it will fit all but my smallest sail - which I can always run on my North boom. If I cut off 10 cm as per the Neil Pryde link above (thanks FormulaNova), it will fit ALL my sails (4 - 7.5) and still won't be at full extension.
Ah, the days when you could order Custom Booms, hey Daffy
I sold a Proto Type boom last week $50.
Perfect for a small speed sail.
165 - 190 which could have been shortened with a hack saw
All 2mm thick alloy (heat treated), monocoque construction.
Head to fit either RDM or SDM
28mm grip
Rear end suitable for Hydro Adjustable Outhaul.
Only problem, it had yellow grip at the front