Razor Specifications

I get lots of inquiries about Razor, so here are the dimensions and some pics of the latest variation. Of course, Razor is always a work in progress, so I don’t guarantee that it will stay this way! :smiley:

Razor Dimensions:

Front Edge of Mast Box from Bow 100mm
Rear Edge of Mast Box from Bow 140mm
Center of Gravity for Fin/Bulb from Bow 165mm
Depth of Keel from Hull Bottom 170mm
Width of Fin at Hull Bottom 55mm
Depth of Rudder 90mm
Width of Rudder 50mm
Extension of Bowsprit/Bumpkin from Hull 75mm
“A” Rig Height 650mm
“A” Rig Jib Boom Length 210mm
“A” Rig Main Boom Length 180mm
“B” Rig Height 550mm
“B” Rig Boom Lengths 210mm
Ready-to-sail Weight 1.25 lbs

These dimensions are a starting point for your own thinking. Footys are a development class, so try something new. If it works, please tell us about it.

The pics show Razor with 2 different rigs. I’ve tried to include enough detailed close-ups so that builders can copy what they like. The “A” rig with the blue-trimmed sails shown here is from Dennis Desprois. Dennis’s sails are far nicer than mine. The “B” rig shown in Part 2 is my own creation…very low budget but works just fine. Both are shown in action on the water in Part 3.

Keep your best Footy forward :wink:

Bill H

Here’s more Razor pics to help you build.

Here’s some pics of Razor sailing. Much has been said about the difficulty of sailing Footy class boats. Unfortunately, much of that has been said by people who have little experience with them. A Footy can sail very well, and Razor proves it!!

I’m not saying this to brag…I just want to encourage builders to do a good job and end up with a good-performing boat that they will be proud to show. If you build her well and tune her well, Razor will reward you with hands-off sailing on most tacks in winds of 1-10 or so. If your Razor won’t track straight in steady wind, and handle puffs without radical changes in direction, something is wrong with your tune, so ask us for help!

Keep your best Footy forward :wink:

Bill H


Thanks for the info. Now I can crack on. I put together the basic hull in a couple of hours using 1/32 ply and your hull forms and 5 minute epoxy. When I’ve got it something like I’ll post some pictures. I was hoping to use a Stollery swing rig for the top suit and a conventional rig for the smaller. Shouldn’t take long to to put together and could be on the water in a couple of weeks. Got a major 2 day race for free sailing “M”'s at Fleetwod this coming weekend so not much in building terms going on then.

I noticed from your pictures you have a pretty large fin area, is this because you have found that it gives you greater directional stability?

Bill G :smiley:

How did you run the sheet for the jib? It looks like both lines go through the arm then to the back of the radio hole, then what?


DSCF1320.JPG shows that quite clearly I think TomoHawk

Nice posting Bill… good sailing photos.


Bill G, I’m still experimenting with fin planform…and I’m not yet confident to say what works and what doesn’t…my earlier fins were narrow, this one is way wide, maybe the best is somewhere in between…I don’t know what the tradeoff is between directional stability and additional drag…but directional stability is an important factor with Footys…they just don’t have enough hull length.

I think there would be a lot of interest in seeing pics of your swing rig…I haven’t gone in that direction yet…so much to try, never enough time!

Tomo, the sheet arrangement is a simple double purchase…both sheets are anchored on a hook in the aft corner of the hull (under the little white deck patch) then they go through the servo arm, out the aft fairlead, then the jib sheet goes forward to the eye in front of the mast…the double purchase arrangement gives me just the right amount of sheet travel with the length of the arm pictured.

Graham, I have to give my wife, Sheila, credit for the sailing photos…I’ll tell her you liked them…thx.

It occured to me that many folks here may not have been around to see the original Razor, so here are a couple pics that show the first version…she’s come a long way, baby…from fun boat to racing machine.

Bill H

I’m curious about the directional stability point. I find it difficult to believe that area added to the trailing edge of the fin so close to its fore-and-aft centre of lift (= the centre of action for yaw for all practical purposes) can have any measurable effect. The lever arm is just too short.

A ventral spine with the rudder slung partly or entirely below it would probably work better.

On the other hand, it may be that ‘twitchiness’ is the result of standard yoke bar/transverse tiller arm steering.
Our whipstaff steering gear is intended to overcome this problem. For a given servo input, it gives minimum response at the straight ahead position - in other words the helm is damped. It is interesting that quite a lot of vane gears of the 1950s were geometrically whipstaffs, although I only realised this AFTER I’d reinvented the wheel!

There are now some rather crummy photographs of an almost complete whipstaff gear in the Whipstaff Steering thread.

Does that get you any extra drag through the arm? I didn’t notice the deck patch until you mentioned it… Only a sliver of one edge is visible in the picture. What is the patch for?

There probably is some drag through the arm, Tomo…more sophisticated versions would have a block to run the sheets through at the end of the winch arm. The advantage, though, is the additional sheet travel you get from the double purchase, as opposed to directly anchoring the sheets to the arm.

The little deck patch is to cover the hole I cut to give me easier access to the hook where the sheets are anchored. Small boat, big hands, all thumbs…access hole comes in handy.

Angus, I gladly and respectfully defer to your knowledge of the science regarding directional stability…way over my head. I don’t have any yacht design background, so I approach design issues empirically…that’s why I’m not trying to say what works and what doesn’t. I’m pretty happy with the overall combination, even though I don’t know which design element contributes to which aspect of her performance. Of course, she hasn’t been tested in fleet racing yet, and any boat looks fast by itself…but next season we’ll see.


All mm mesurements and a imperial weight, your worse than me:D
Sorry to bring up a old trhead but I want to know the razor displacement in grams, when I use my little conversion utility I have a choice of troy or advp pounds. One gives me 566 g the other gives 466 g. My razor is 488 g with the ability to shave some off. I have used lithium batteries. Local electronics shop had them for $7.50 au packet of 4.

Hi Nick,

Razor’s target displacement is 500 grams. There are both lighter and heavier versions out there, but 500 grams puts her on the designed waterline.