Questions and Answers on Rigging a Spinnaker Pole Launcher System


Ali Meller asks:

Dear 505world:

After years of using the spinnaker pole trolley system (aft end of spinnaker pole rides on a shockcord loop running from aft end of boom, around mast, and back to aft end of boom), I want to try a Spiro spinnaker pole launcher (yes, I know I have long favoured the trolley system.. I still feel it has some advantages over the Spiro pole launcher, but....) Who knows, if I like the Spiro pole launcher I may even consider trying a launcher equipped 505 rather than the forward tack bag boats I have favoured for the last 16 years (one has to be willing to try something new).

I have the Spiro mast and pole end fitting, but wanted to ask all the pole launcher experts what the best way to rig it is.

How far above the deck band do you put the mast fitting on the mast?

What type of line do you use for the launching line? 
Marlow super-prestretch?

How do you run the pole retract shockcord? How many times fore and aft in the boom? What thickness of shockcord?

Does the "thru deck" mounted at the back of the boom go in the top of the boom, or the side?

How does the shockcord at the front of the boom (usually a loop of shockord around the foreward end of the spin. pole, that goes into the boom through another "thru deck" fitting, work? Thickness? How do you lead it?

Is the Spiro fitting mounted perfectly square on the mast, or is it angled slightly to one side or the other?

Are the two mounting rivets sufficient to hold the fitting on? I have heard that they sometimes crack at the mounting holes, and some people customize the fitting by cutting away the fitting at the forward edge of the mounting hole, drilling new mounting holes where the material is thicker, and sometimes even removing the roller and drilling a third mounting hole in the centre (and then figuring out how to put the roller and ball bearings back).


Larry has his standards which are: Spiro on mast 1125mm (44.25") above deck, this would be to the center of the sheave. The Ronstan RF5, mounted approx 1/2 way between the boom and deck, tapped into a slider. The Harken single exit mounted on port side of boom 16" forward of the boom's end. The 16" is to the back edge of sheave. The shock cord take up runs on Harken Micro double and Harken Micro single w/ becket (This runs 4 x the length of boom). Remember to use two rivets and one screw (centered) on the Spiro mast fitting. Only the rivets tend twist and snap the fitting.

Paul Muus


Ali - here's some pole launcher info from Mike Martin:

The shock cord goes in the back through a Ronstan narrow exit block mounted on the TOP of the boom, it then turns at the front of the boom, and again at the back and dead ends at the front. We use 1/4 inch shock cord, Marlow is the best, but the West Marine stuff will do.

Put the fitting on perfectly straight. We also have a extra piece of shock cord that helps pull the pole off the fitting.

The line that you use to pull the pole out is actually very important. The smaller it is, the better, but it is rough on your hands. We use 5mm Marlow covered spectra. A smooth casing is important.

We do not file the ball.

Mike Martin (forwarded by Jesse Falsone)


Marlow tapered spectra for the line works well. 3/16" shockcord.... must be tight enough for the crew to really have to tug the last few feet, before it goes into the mast fitting.

Paul Muus


How far above the deck band do you put the mast fitting on the mast?

Exactly at the spin pole ring measurement. 1125mm from bottom of the mast.

What type of line do you use for the launching line? Marlow super-prestretch?

As this is not such a critical component of the boat, i.e. subject to stretch and creep conditions, Marlow would be just fine.

How do you run the pole retract shockcord? How many times fore and aft in the boom? What thickness of shockcord?

The shockcord is knotted inside the spiroball end of the spinpole. The cord is then lead through the opening and over the top of the spiro knuckle. Now here is where I get a little mixed up. I am trying to visualize how I rigged it on one of the J-Town boats after the system failed. AHA, Now I remember! You take the shock cord and lead it aft to the end of the boom on the starboard side. At the aft end of the boom, install a block which will turn the shock cord forward inside the boom to another block (attached by a line to the forward end of the boom, and turn the shock cord around it and lead it aft again to be dead ended on the port side of the aft section of the boom.

Does the "thru deck" mounted at the back of the boom go in the top of the boom, or the side?

See Above.

How does the shockcord at the front of the boom (usually a loop of shockord around the foreward end of the spin. pole, that goes into the boom through another "thru deck" fitting, work? Thickness? How do you lead it

Not required any more, see above.

Is the Spiro fitting mounted perfectly square on the mast, or is it angled slightly to one side or the other?

Spiro mounting bracket should actually be square to the mast but the knuckle will be angled to one side or the other.

Are the two mounting rivets sufficient to hold the fitting on? I have heard that they sometimes crack at the mounting holes, and some people customize the fitting by cutting away the fitting at the forward edge of the mounting hole, drilling new mounting holes where the material is thicker, and sometimes even removing the roller and drilling a third mounting hole in the centre (and then figuring out how to put the roller and ball bearings back).

Haven't seen one break yet.

Hope this helps Ali.

All the best

Pete Epstein


I will measure the SPIRO position on our mast and get back to you. Whats really important is that you try the position on your mast before drilling any holes... you can do this easy using a strong thin rope (spectra) and a screwdriver. Its a little complicated to explain how...but just tie the rope through the SPIRO and around the mast, attach the screwdriver through the rope on the back side of the mast and rotate it so the rope strech, then use another rope and tie the screwdriver parallel to the mast. This will force the fitting to stay in place while you are trying out the best angle and height. Its important to verify that the rope is not climbing on the SPIRO sheave, do this by pushing the boom out maximum (against the shrouds) and pull the spinpole up. YOU MUST VERIFY THAT IT WORKS FINE HAVING THE BOOM OUT ON EITHER SIDE!!

We use a 6 mm (close to 5.5) Spectra rope to pull the spinpole. The cord is Marlow 5 mm (plastic cover) and goes from backside of boom to front and then to back and front again and then back and tied with a knot at the back end (I hope you can follow...)

Ebbe Rosen