Homebrew IOM

Early November I started this scratch build IOM and she’ll be ready for her first race on the 1st Jan weather permitting! In the past I have been a very keen multihull racer in both the A Class and F16 and perhaps I have encompassed some of their design looks in this IOM.
I have documented the build in my blog if you’re interested;

I have encompassed some of their design looks in this IOM.

Nope looks pretty standard fare to me though I would be interested to hear what the boat weighs

I think you have missed a word out from your quote “perhaps” it makes all the difference :wink: Here’s a photo of a Chris’s DNA and my homebrew.
I also personally think it’s far from standard for the following reasons
My bows are oval in shape
No flare
Slightly dreadnought, raked backwards
The hull is hard chined
Max rocker set in front of mast
Shrouds will terminate in hull sides and not deck mounted
No mainsheet post
Jib sheet will partially run internally to foredeck
The pot is 1/2 the size of a UK standard pot
The rudder servo isn’t a standard size but 1/12th scale
As for the weight;
fin and bulb 2500g
complete hull inc rx and 6V batteries 1192g
A rig 258g
Total 3950g excluding correctors

Primer is ready to race. However , there are a couple of small paint touch up’s required following the final major sand and polish. No racing today due to the weather so I have plenty of time to do this before next Sunday.

Primer’s maiden, B rig with some big gusts, mainly sailed in a sheltered area nearer the jetty


It’s filmed in HD so to improve the quality press on 360p when the clip starts and then choose 720p

Very nice work!
I hope you don’t mind answering:
How did you find the helm balance when heeled right over?
Hard chined hulls can have a tendancy to want to round up when hard pressed and I am curious to see if she has this characteristic or not…

Thanks, Jim

Hi Jim
I was also worried that she could be difficult to sail upwind, believe me. I had been expecting the worse! However, and you’ll just have to take my word on this, there were no dramas.
In fact most of the filming was done with my right hand so I had very little steerage control, when you see her beating to wind she tracks really well and even in the big gusts she doesn’t broach savagely and screw up.
I have no explanation, it’s not something I could put a finger on and explain why she is well balanced. I guess it could be beginners luck :rolleyes:
Tomorrow we should find out if she has the potential to win races.

“Hard chined hulls can have a tendancy to want to round up when hard pressed”

The Lintels have long, hard chines, and sail “hands-off” at the top of rig conditions. I’m not sure where the “tendancy” statement originated! :slight_smile:

Primer completed her first races last Sunday. Unfortunately the wind was so light that the chines stayed pretty dry throughout. I have written the following in my blog;

Primer’s 1st race
The forecast was a westerly 8mph wind, windguru went as far to predict up to 15mph. At the lake there was next to nothing!!
When I arrived a small group of members were very keen to see Primer and like a proud parent I showed her off. They all appeared impressed by the build and quality of the finish but I sensed some differing opinions on whether the hull design would prove to be a brit-pop or brit-flop.
Primer was then launched and slowly but surely made some headway, this prompted the other skippers to rig and launch, a couple of the regulars weren’t there so numbers were reduced to nine and with one TX suffering a major hangover only 8 competed. Ian laid a slightly smaller than normal triangle, sausage course with the start line adjacent to the control area. Thank goodness as I’d forgotten my glasses.
There’s no real point in going into too much race detail as it took around 30mins to complete the first race. However, I was pleased with a third place, probably should have been second but I was being tolerant when the handicapper that came 2nd appeared to have her bow bumper ‘hit’ (french kiss) the last mark for some time before rounding but no exoneration was apparent.
There was no difference in the second or third races, both took 30 mins. However, in the second a group of 3 boats eeked out a lead but Ray who was leading and Ian to a lesser extent sailed to low on the penultimate leg allowing me to pass them both giving Primer her first victory. The 3rd race I lost the lead to Ian and Mike at the first mark rounding but then both myself and Ian pulled away. Ian gained a comfortable victory as I was 2nd being approx 1 min behind and the rest of fleet 4-5 mins behind me.
I can’t say I’ve learned that much about Primer’s potential. I am however glad I ended up second overall which might have been a struggle to achieve had I been racing the Lintel.

Very cool, I like the chines. Our original 6’ design was hard chine, it sailed very well.
There were a number of benefits to the chines for sure. The biggest downside we found was tacking in big waves & chop, it would pound when the hull came upright mid tack.
Here’s a slide show of “The Box”


Primer is proving to be a fast IOM. I’m slowly finding out how to tune the rigging for her needs. I am practically there with the B Rig but have a little way to go yet with the A Rig, last time I raced with the A Rig there was way too much mast rake so her performance was terrible, once I had figured out the problem and made the relevant adjustments an instant improvement was evident and I won the following race.
I am still of the belief that improvements to the hull can still be made in future designs especially between the bows and midships but hard chines could be the future!
Here’s the latest crop of Open 60’s and the majority have chines. I’m sorry the screen shot is so small, here’s the URL address to one of the yachts: http://www.accionasailing.com/