Henry McCray's instructions on building your mast with deck-level rig tension

How to build a Stratus-- foolproofed by Henry and Gary.

Order the spreader fittings unrigged--- not on the mast. You want just 5 'T' terminals (2x shrouds, 2x trapeze, 1x forstay) installed. Have the gooseneck installed, mast cut to maximum length (bearing surface of mast tip shive about 1" above the bottom of black band) and the heel plug sent separately-- uninstalled. Have them mark the placement of the three bands, and the maximum and minimum spreader height in permanent magic marker (acetone will take care of it later...)


Run a piece of line for a practice main halyard, exit out of aft slot below deck level, run through a clam cleat, and have a 16mm below it for a turning block. Also acceptable is a starboard slot just above deck level with the same arrangement. Use 5/32 covered KY-3 Kevlar, or splice a 12" cover (24" piece) onto a 1/8" vectrus halyard centered just where the cleat sits. Make it long enough to hang the boom by the main halyard. I have it just the right length dead ended by a twing ball at the turning block. You will love me when you drop the halyard and the heel plug is out IT IS SO EASY! Tie off TIGHT before you proceed.

Now center, mill, and rivet a nice H421 for the spin halyard (use 1/8" uncovered spectra, dyneema, or vectrus--- 40'.) and an exit hole- starboard. (***if main is above deck it must be on the same side as spinnaker, and opposite or in front of jib halyard, which exits best aft through a milled slot where old style jib hlyards used to exit.***

Next center, mill, and rivet the second H241 for the jib halyard below but close to the black band. Use 1/8" vectrus (21', spliced and looped on both ends, use a 1/12" messenger to raise and lower jib. Tack need not be adjustable - tied in place if fine, or a shackle. A jib cunningham can be cool--- that will allow the jib to ride up and down the wire without effecting tension-- really a lead angle adjustment. Pretty neat, eh? ***do not exit on same side as main OR spinnaker- trouble if you do...

You have a good bit of control over the power of your rig by thinking about spreader heighT. (spreaders are centered on the collar) Request a LOW spreaders for easier depowering luff curve sails (North, Hyde, Rush, Irwin (Diamond)) and HIGH spreaders for a straight mast sail like a hood or P&B. Factor in Crew weight- higher than normal for heavier, lower than normal for light. Tof sailed at max low with Peter at 140lbs.

Yourself method:
Attach blue collar at spreader attachment placement, being careful to mark your actual placement all the way around the mast so you can see when the collar is on, and premark the centers of the collar. Use a soft metric tape to center the face plate- seamstick (double sided tape) sets the tape measure in place well to get a goo mark.. Set the front sprdr. attachment plate in place with double sided tape (or something, I use seamstick...) and recheck your measurements one more time. Then drill for 3/16" rivets (big and HEAVY) and fix the plate in place.

Then cut a set backing plates (for the rear spreader attach forkplates) with a hacksaw from two facing corners on the second collar (approx 40mm x 20mm). These plates will save you from the Egli syndrome. - pinched mast track at the spreaders. Just cut the collar even when you are done, it will still be attached to the stick-- at deck level. You are using the collar because it is radius'd-- not flat. The forkplates themselves are angled with rounded backs, the 90 degree side is fore and the long angled side is aft- I have messed this up before. Set the backing plates first with seamstick, then the forkplates (again stuck in place so they don't slip while you....drill for 3/16" rivets and lock it down. THEN go back and rivet the four corners of the collar, with smaller stainless rivets.

Attach dyform forestay (cut to length taken from standing rig at 22'10" 400lbs on forstay minus four inches. Attach shrouds (cut like 10-12" above deck, but EVEN-- the English are notorious for cutting different lengths and using unmatched chainplate holes) and stand new rig- just plae mastbutt on for now- and when you do screw it TAP THE SCREW PROPERLY>>>>in five years it will still come on and off easily- unlike always stripping self tappers....

Here you go
You need to find a way to attach the 1.5" wire shive block on the jib halyard hole on your bow fitting. You can usually remove the shackel and spacing piece, and use a 1/8" x 1/2" (3mm x 10mm) stainless shank bolt (smooth and then threaded- like a cb bolt) right through the existing hole. If this is for your a boat see the class rules appendix 2, drawing A.

Splicing vectrus- cut a 150mm section of coat hanger and file both ends smooth. Have a roll of electrical tape handy, and scisors (have to be SHARP- K-mart sells 8" SS Fiskars for 3.99- you will need them.) CUT a 20-30mm piece of electrical tape will get a feel for it) and tape a loose end of vectrus to one end of the hanger. Make sure to make a smooth transition from line to hanger or you will get a bump- not too much tape though or it will jam in the splice... Make a Mark 180-200mm from the taped end of vectrus. Pushing the line together (opening/bunching the strands) pass the open hanger end through the mark, and pull the line through the opening making a loop. Adjust the loop to the desired size (small like 5mm is better than long, like 40mm) and then pass the the "needle" through the braid again, this time in the opposite direction a few strands back from the first pass. Make a total of three, and then take the needle and insert it IN to the core- pushing and bunching the line- inching it up the needle until you reach the bump where the taped end of vectrus sits. holding below the 'bury' entrance pull the opening as large as possible- it will settle back. Then work the taped in down the core until the taped end is burried and no slack is left in the loop as you pull through. Then work the TIP of the needle out from inside the core and pull the taped end all the way out -- The loop will likely all but dissapear- you can adjust it later. With the taped end unwrapped begin to work the splice tight- slowly messaging the line to tighten the splice. By pulling gently against one side of the loop and holding (not pinching) gently at the first splice pass you did- adjust the size of the loop. Pull tight by putting a rod or something through the loop and pulling (behind the splice) hard. Message the splice until hard (sounds like fun, eh?). Measure out by using one spliced end and marking your other end. Then add your 180-200mm and repeat splice, passing directly through the overall length mark you wanted- this appears to make the loop beyond you desired length but vectrus measures short in a splice. You may need to adjust the loop to get an exact measurement. Keep in mind you can only ease a loop, to tighten requires pulling the splice and starting again (you'll see.)

Start with the forestay connector- 5/32. splice one end and attach to the forestay with a good stainless shackle- rounded edges please- vectrus is very good with chafe but hard corners will cut anything if it rubs long enough. This is the one place on the boat to splurge for a nice new fico shackel, a very small one will do nicely. Take the tail and run it through the 1.5" wire block leading aft. Take the weight of the rig with the vectrus and ease it until you get a rake (pulling tight on the tape measure) of 22'2" and make a mark JUST behind the 1.5" wire block. Add 250mm for splice (5/32 gets a slightly longer splice than 1/8) and cut. Make your splice so that a pin passed through the loose end loop prevents the loop from running back through the block (droping the rig back further)-- This is where you will attach the 1" wire block. The wire block then becones a stopper for the forestay in the even the purchase breaks behind it. It will run to a loose 22'2" where 6:1 shroud adjusters can pull the rig back to 22'0" at 250lbs- not a shabby heavy air setting.

We replace the supplied shackle and pin on the 1" wire block with a fico thumbscrew shackle which fits snug on the 1" block (again with rounded edges, eliminating the spacer- the proper shackel will fit sung, but too snug for the spacer....) We then replace the thumbscrew with a regular stainless panhead machine screw, cutting the excess off after installation, removing and carefully filing the thread end. --- why? --- the thumbscrew can chafe and scar the deck. Splice 5/32 vectrus to port eye with a thimble, or just make a loop and use another shackle. Run the tail through the 1" wire block to make a 2:1 cascade on the foredeck. With the mast aft and supported by the 1" resting on the 1.5", run the tail back to the starboard side and make a mark 600mm or so in front of the stbd eyestrap. Add 250mm for splice and cut. Splice through the 16mm tripple with becket-- inserting a thimble -- by leaving a slightly larger than normal (enough to loosely fit the thimble) and pulling the neddle out of the core (to finish the splice) snug the loop tight around the thimble . The splice itself will be loose, but keep the loop snug around the thimble and work the splice from the loop on back until it is hard. The 16mm tripple can be shackled to the stbd eyestrap.

It is important to splice the Marlow Excel control line. Take the 5/32 covered dyneema and use your needle (hanger, real needle, fishing hook, take your pick...) to open a hole in the cover about 500mm back from one end. pull the dyneema core out through the hole until you have 2 500mm pieces- core and cover. Cut the cover 150mm from the split. Attach the end to your splicing needle just like the vectrus. Pass through the core twice (three passes total) and then bury the cover inside the core, exiting just like vectrus and tensioning the splice (by pulling on the loose end with the splice loose, and working it tight from the beginning out until the cover buries. You will then have 300-320mm of uncovered core behind the splice- use this to back splice just like vectrus around the becket on the 16mm tripple. String it up, and forstay is done.

Shroud adjusters

I would strongly recomend a 3:1/2:1 cascade like ours or Tof's because of the 1000 pound working load. Take the H244's and drill out the rivet for the top sheave. Replace the top sheaves by thru-bolting 1" wire sheaves inplace of the plastic ones. Use short splices beginning with the 5/32 vectrus on the becket. The becket block attaches directly to the shroud with a 1/8"x1/2" machine screw/bolt just like the 1.5" forestay block- make sure to use lock tite. The vectrus should lead down from the becket, through the 1" replaced sheave (v cleat facing aft, pin through shackle attaches 244 to chainplate ***with the shackle still attached and folded forward until it rests against the body of the 244. The 5/32 continues back up through the 1"w/bkt. Pull the mast forward until you measure about 23' then pull one shroud tight and mark just behind where it exits the 1" to make 3:1. Splice 16mm single there. Ideally the 16mm airblocks spliced on will be even and bottom out (or top out as it may be) against the frame of the 1" wire/bkt block. If you did your 5/32 work evenly well you should be able to pull on even shroud tension around 23' rake. Pull on rig until very tight (3/32 dyform about 35-40 on a loose 'b''.) This is to creep the splices out- just leave for about 5 minutes and then give solid taps with a hammer on the shroud- ((middle c?)) This will help the last micron of splice bunch to creep out while under even pressure.

The 2:1 will be the actual cleated control line. Splice a 3' piece of 1/8" with a 30mm long loop. Hold the loop together and pass through the shackle at the base of the 244. Pull the tail of your piece through the vectrus loop- effectively tying a slip knot around the shackle. This looks a little sketchy, but we are getting ready to do our third workds after countless hours of practice with the same shroud adjusters- it wont break. The line goes up, through the 16mm, down and back out through the bottom sheave and the v-cleat. Do not tie any knots. Make a matching adjuster now- just get it close and then adjust the loops to get them perfectly even.

Trick--- lay a rod across the table overlapping one leg. Hang one piece with a lead fishing weight (8oz at least to take up even slack) shackled on. Measure up from the floor and mark the table at the tip of the weight with a piece of masking tape. Use the SAME weight and shackle and repeat the excerise with the other piece, adjusting the loops one at a time until they are dead even hang under equal (low) pressure.

The real key is where you put the stopper knots. A half hitch will do fine- you get a little chafe-- but like I said, we are at two years and ticking and they look no worse than two days old/ Before you tie a knot have someone sit in the boat and hold both shroud tails. Pull the rig in the middle somewhere (shoot for 22'3" hand snug) and tension up about 200 pounds. Check rake again. You are looking for about 22'4", 200+ pounds's. (Whatever you can get on and still easily keep the shrouds from slipping just by holding them.) Check both shrouds for tension- they MUST be even. Then sight the mast- it should be straight athwartships under tension WITHOUT mast gates (it would be prudent at this stage to have checked the spreaders for even length and deflection). Then carefully mark a common spot on both adjusters on the 1/8" just behind the v-cleat. Go ahead and tie a knot on each side now... use a ruler.. this is CRITICAL. Get the knots EVEN. Retension to 400 pounds on headstay, 700 pounds on shrouds (Really tight.) Check the mast for sideways bend and for equal tension. If you try you should get it the first time. This is your middle test position, only a test--- put a mark on both sides on the 1/8 cascade somewhere-- as long as it is even to within a mm. Ease, pull the two half hitches back out and then pull the mast all the way back. If everything specs out, you should have a tought, dead ended headstay around 22'2" and the airblocks should not be bottomed out, but getting close-- mark one side at the back of the 244. ease rig and detatch adjusters. make the first knots bearing surface 18mm past the mark (sheeted tighter, 3mm overall shorter shroud than the mark so mast is tensioned from the shroud adjusters at rake max aft (forstay bottomed out). Then one set at a time make knots 48mm in between bearing surfaces- checking each set as you go. One off in the middle means a they are all off. Each knot will then ease the 8mm or about 2" rake with even headstay tension. We have five knots total. Each knot corresponds with a mark on the fordeck for it's rake at 400 pounds. Make the mark and numbers big enough to see, and use pencil to start with. Pull the rig all the way back- the last knot will be shy of coming out through the cleat - pull hard (tensioning the rig one shroud at a time) and set on last knot. The rig shoud be tight- maybe very tight. Good. Check rake. This is your oh shit setting. Forestay just snugged to take 1" wire block from two blocking with the 1.5. You should be in the neighborhood of 21'10" to 22'0". Less than 21-10 and you need a sixth set of knots- no big deal. More than 22'0" start over with a two new pices of 1/8". Be more careful.

Tune your spreaders. 405mm for depower, up to 430mm for power. really light people go to 395mm in stink- there are reasons that is a potentially bad plan - stay at 405 and tune the spreaders so the desired prebend for the sail matches the 3rd or 4th knot- which ever is closer to 22'5". Rake will now increase bend by about 1" per knot. Light trap setting will be a slightly straighter setup, and max forward will need strut up assistance for flow down low.

You get your settings by first ignoring rake and simply stepping down knots, and marking 400 pounds on the forestay in easy to read numbers. You will quickly memorize knot number by looking at the height of the 16mm.

knotforestay marktension
bottom knotforestay maximum250 pounds
2mark '2' at back of 1"400
3mark '3' at back of 1"400
4mark '4' at back of 1"400
5mark '5' at back of 1"400

You will find the rakes will be in the range of- 22-0 22-2 22-4 22-6 22-8 (extra knots can be necessary- you NEED 22-8, and 22-10 doesnt hurt. Make a simple marker chart on the tankside somewhere of the rakes at 400 pounds. Then, start again and calibrate by pulling the rig to rake and how close the forestay mark is- if it is off something is wrong- leave the thing tensioned for 15 minutes and have a beer. It mayhave been splice creep. Keep going up and down until you get the same thing every time. Make a mark on the forestay control line at the cleat at each setting. That way you can pull close to the right thing by looking at the foredeck, and then look for the little mark on the line. This works really well.

400 pounds forestay is the required amount to keep zero luff sag up to 20 kts. Anything less is a compromise.

NOw... back to rigging the mast. Install the deck fitting for the strut. Attach the strut at the deck and pull the rig all the way back. Tape the track to the mast so the car is at the bottom of the track in this position. Pull all the way forward with the car attached and the track taped on- 8" should be enough but leave it long initially to be sure. You need enough throw to allow 4" bend at max upright- bend the stick with the vang (main hal tied to boom end) and mark either the top at 8".

Attach the strut car track to the mast. Harken Part number 154 (24" enough for three if you are careful) has a flat back- you need big heavy pop rivets. Make sure the 8" section has at least three holes. More can be made- but countersink is required, so a drill press would come in handy. Put the 173 stopper end on the bottom (self tap into pilot hole in track only, or use a tap and a machine screw (preferred) and the 261 finish cap on the top, set in with clear silicone.

You will need a Ronstan rf-214 gudgeon for the car/strut connector. It needs an additional hole drilled to fit the set screws OEM from Harken. There are a hundred ways to attach the strut systems to the car. The 16mm cheek goes above the track, slightly off to one side and is the turning block for the strut up. Use a Vectrus connector up and through the cheek and splice on a 16mm single to cascade the strut up- this is a good place for it. For the down, we use another 1" wire block with a 60mm vectrus loop which fits over the and behind the car, resting on the top set screw. We cascade again to get 4:1 before we turn back along the case with a 16mm cheek. The tail splices on a 16mm double, which is the front part of a 4:1 to power the strut down at a total of 16:1- or equal to the vang - ALWAYS!!! Some also match the strut up purchase and loop the control lines together. Baldereash. The strut up is a SPINNAKER TOOL FOR MAIN DEPOWER ON REACHES, counteracting the aft force of the spinnakerpole, and keeping the main flat (assisting flow- especially with FLAT spinnakers.)

We have the top of the strut milled out so the strut up loop attached directly to the strut attachement pin- critical for hairy reaches.

Your exit 16mm will be for the topping lift (exit left.) The proper position for a single ended pole is 1/2 between spreaders and hounds. The topping lift must be opposite the spin hal, and must be across from or in front of BOTH jib and main halyard... It is the topping lift which most often binds with the spin halyard. Without a 7x19 internal jibwire that TWISTS as it runs through a sheave you should not have a problem.

Splice your trapeze lines. 1/8 vectrus is much lighter, stronger and more durable than 3/32 1x19 stainless. It has a working load max of 2000 pounds, unlike ROTM 1x19 which is around 1200. Keep in mind at that rate you would explode a Harken wire block before a spliced piece of vectrus. Run a 5/32ss bolt (not machine screw) all the way through the mast. 2 choices- bolt head/penny washer/vectrus/ mast/ vectrus/washer/nut or... bolt on a 30x10mm tang with a hole at the top and bottom (corners very rounded if you like the head of your kite...) and slightly bent in the middle. Run a thimble through the bottom hole and splice around it. I have one on each of my Masts. Makes no difference..

Add your masthead fly. They are important. And they look cool. And that might be the only way your mast will weigh without lead SO GET A BIG ONE BABY< YOU'RE LIGHT!!! I really prefer one with tabs to steer by apparant wind upwind in up and down stuff.

Well, thats enough. tie it all off and go.

we ELIMINTE compression.
we lower our tip weight by over 1kg.
we strengthen with collars at the two most common failure places.
we use better parts- Proctor blocks and sheaves SUCK.
we use better line. Vectrus. great with uv, no stretch, no creep (I mean NONE) no chafe
we use better spreaders- the 1/4 twist adjusters only thread one end- they don't blow up
we use a vectrus main halyard. I have the only main in the fleet always at the top- at less than 1/3 the weight of a wire!!! Even when the cunningham is cranked!

I highly suggest a new spinnaker pole. you will be amazed. They are less than 80$ from LDC. Get the super spar (blue only) and super spar ends (even ion a proctor pole-- but get the thicker one (comes in black....)

The new 2633 boom weighs half my 1989 model. The tangs have improved a lot, and tapered helps on reaches whe your boom catches a wave (previously a time for death- now a non-concern, LDC sells em' for like 89 pounds for the cool tapered model with 3 pairs of lightening holes and a heavy duty vang extrusion (wrth it's weight in GOLD.)

Editor's Notes: If all this sounds like too much trouble, just call Henry and he'll be glad to sell you a mast rigged in this fashion. To be class legal with this system (ie: with forestay supplying the rig tension) you HAVE to use a hank-on jib so that the extension of the luff of the jib will be below the black band - check the class rules! An alternative method, used by Tom Egli, is to eliminate the jib halyard completely, and attach the jib luff wire to the mast with a T-terminal and tension that at deck level to provide rig tension. Tie on the head of the jib to an eyestrap on the mast near the black band. Simple, allows the use of conventional stuff-luff jibs, but inconvenient since there is no easy means of raising or lowering the jib.