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Telescoping Whisker Pole Project

Started by Captain Smollett, May 03, 2014, 04:36:44 PM

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Captain Smollett

Gaelic Sea has several head sails at present and I have plans to add a couple of others (including a drifter and storm jib).  I want the capability to use a whisker pole, so my choices are:

(a) use a different pole for each headsail
(b) buy a commercial multi-size pole (telescoping)
(c) make my own

Option (a) is not practical on a 30 ft boat; I chose (c) for cost reasons.   The project is not complete yet, but I've got the pieces ready to go.  I've done some dry fitting, so all that really remains is actual assembly, aside from some fine tuning in the measurements first.

The parts shown below, mainly Aluminum tubing and Forespar end fittings, put the total cost at a bit less than 1/2 of what the commercial, less KISS whisker poles run.

Step 1:

I chose to use Forespar ends for my pole, so the first step was to match end sizes with tubing sizes available for aluminum tubing from onlinemetals.com.  In addition, I wanted to stay near the dimensions (diameter and wall thickness) used in commercial poles, so mostly this was a matter of determining OD and ID of the commercial tubes.

I ordered the ends and the round tubing, check fit and went to the next phase of the design.

Step 2:

I needed the inner tube to slide inside the outer one rather snugly.  The actual OD of the inner tube is quite a bit smaller than the ID of the outer tube, so just tube-tube fit is sloppy and I would not really want Al-Al rubbing the whole length of the tube(s) due to too much friction.

So, I needed to make some bushings or sleeves.

Note that I am not trying to make "twist lock" or anything fancy like that.  I will secure the length with a removable pin; it will not be settable to any length, but only those lengths that match the foot length of my head sails.

This introduces another reason I chose to make my own and forgo some of "complexity" of the commercial systems.  I've read of real offshore sailing where 'adjustable' spin poles and the like are a point of failure, and simpler designs being better.  Chalk one up for KISS, and KISS in this case is also quite a bit cheaper.

I chose wood for my bushing material...simple scrap pine.  I'll coat with resin before final assembly, but little of the bushing will be directly exposed to weather.

I used Lenox hole saws - the kind that use a thread and lock to change hole sizes - and removed the center pilot bit.  The hole saw sizes were chosen so that the smaller one matched the OD of the inner (smaller) tube, and the larger hole saw matched the ID of the outer (larger tube).

The procedure was to cut the first (inner) hole, change hole saws without moving the work piece and then cut the bushing out with the larger hole saw.

Here's the setup of for the first inner inner cut:



And, after the first outer cut, with the bushing carefully removed from the hole saw:



And, here's a shot with four complete bushings cut out:



I have not decided yet if I want to double them to make the bearing surface wider, that's why there are four.  Right now I am leaning toward "no," but I'll do another dry fit and decide after that.

Step 3:

To put it together and make a telescoping pole, I will:

(a) Attach one bushing to the inner end of the smaller tube, of course before the inner tube is inserted into the large, outer tube.  Being fixed to the inner (sliding) tube, this bushing will slide along the inside of the outer tube.

(b) Insert the bushing end of the inner tube into the outer tube.

(c) Slide the other bushing over the inner tube and into the very end of the outer tube, and attach it there to the outer tube.

(d) Attach Forespar ends to each tube and any other hardware (such as a bridle for topping lift).  I may need to attach a small collar on the small tube to keep it from sliding all the way into the outer tube; the end fitting should prevent it, but I may do something a bit better (and less likely to mar the end or damage the fasteners).

(e) Extend to proper length and drill pin hole for each headsail.  I'll probably insert some sort of bushing material here to prevent wear of the pin on the aluminum.  Maybe a rubber bushing or grommet of some sort would work nicely (tight pin fit as well as helping to prevent wear on the tubes).

Here's a shot of the end detail sort of in the process of some dry fitting, with the ends shown as well.  Note here I'm showing both bushings as a pair, but I may not use it that way in the final fit.



Note also that the "inner" bushing is not shown all the way inside as then it would not show up on the photo.

Finally, here's a shot of the whole tube length.  Durango provides good scale.



The fully compressed length is about the size of the working jib (so maybe not good for a storm jib, now that I think of it).  Full extended length will match the foot size of the largest genny I ever plan to use.
S/V Gaelic Sea
Alberg 30
North Carolina

Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover.  -Mark Twain

s/v Faith

I ditched Faiths (non-adjustable) spin pole, I have a light adjustable whisker pole I use.

Emerald Tide has an adjustable spin pole, I suppose I could use as a whisker pole (it slides on a track, and has dedicated topping lift, and adjustment lines)...  I have never found the need to use it though....

I like your project, and your approach John (brilliant as usual).. But do you find in practice that you want for a pole often? 

I ask because I find I can usually "tack down wind? and avoid riggin one at all,  sure it takes a couple extra jibes, but the VMG does not suffer much.

I am interested in your reply.
Satisfaction is wanting what you already have.

Captain Smollett

Quote from: s/v Faith on May 19, 2014, 12:13:07 AM

But do you find in practice that you want for a pole often? 

I ask because I find I can usually "tack down wind? and avoid riggin one at all,  sure it takes a couple extra jibes, but the VMG does not suffer much.


An excellent question and a very good point.

I too 'tack down wind' when I can.  I prefer all the advantages to broad reaching over trying to run, and as you say, VMG does not suffer much if at all.

There are times...however.   ;)

The short answer is "versatility."  I like having options.

Expanding on that a little, there are two (related) situations that I prefer to run, and have in fact missed a whisker pole.  They are related by the concept of "searoom."

The first situation involves sheet based self steering.  Every jibe requires a reset of the steering gear.  If the legs are hours or more in length, no big deal; it's certainly worth the trouble.  But for shorter boards, I could envision growing tired of it.

So, my first "condition" in which running with a pole is favored is when I can employ a "set it and forget it" mode of trimming the boat / sail plan and enjoying the ride.  Long offshore run may not be an issue, but inland moreso.

The second situation is more to the point, though:  Narrow channels and tight entrances.  I have encountered this one and missed the pole (as a convenience to be sure).

As an example, one time I was out on a lake with a first time sailor.  We were approaching the cove we needed to enter where the ramp was in very light air.  One of us sat on the cabin top with a boat hook to pole out the jib and the other steered...worked a champ.

COULD we have made it in 'short-jibing?'  Most certainly.   But, at the expense of a lot more work and, in my opinion, under less control.

Maybe the conditions are 'light air in combination with little sea room.'  We do seem to do a lot of light air sailing here.

So, it's not what I would call a 'necessity' but certainly a tool for the tool box...one for the bag of tricks.
S/V Gaelic Sea
Alberg 30
North Carolina

Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover.  -Mark Twain

CharlieJ

I quite often pole out the jib, some times wing and wing, sometimes just on a broad reach, when sailing back up Matagorda Bay from the jetties to the marina.

It's about a 16 miles sail, and the wind is usually dead aft. Sometimes I even put the 150 on, drop the main and just relax ;) Also thinking hard about an asymmetrical spinnaker for those sails.

My pole is on a track and stows vertically up the front of the mast. Simple to hook up and use.
Charlie J

Lindsey 21 Necessity


On Matagorda Bay
On the Redneck Riviera

Leroy - Gulf 29

FWIW... I think I'd use some sort of plastic, ie starboard or the like to make the bushings.  If the wood gets wet at all, it'll be a mess.  I scored on a piece of 1 1/4 inch thick solid surface counter top, that I am using pieces of.  If you wish, I'd be happy to send you enough scrap to make your bushings.

Captain Smollett

Quote from: Leroy - Gulf 29 on May 20, 2014, 10:52:21 AM

FWIW... I think I'd use some sort of plastic, ie starboard or the like to make the bushings.  If the wood gets wet at all, it'll be a mess.  I scored on a piece of 1 1/4 inch thick solid surface counter top, that I am using pieces of.  If you wish, I'd be happy to send you enough scrap to make your bushings.


It's a personal choice, but I can't stand starboard.  I thought about making a glass lay up, but chose the easier / cheaper route.

I plan to coat the wood with epoxy resin.  In my experience, this is pretty durable.

Thanks for the offer on material; I'll keep it in mind. 
S/V Gaelic Sea
Alberg 30
North Carolina

Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover.  -Mark Twain

Gary Guss

I think I'd maybe use a piece of trex or maybe just a plastic cutting board to make the bushings, or maybe just buy some plastic bushings
Great idea, I see its been awhile, got any recap on how its working?

GG.

rorik

You could seal the wood with something like System Three's S1(?) Sealing Epoxy.
Or maybe make them out of UHMW?
Alice has escaped....... on the Bandersnatch....... with.. the Vorpal sword....