Joining Mast Pieces

Hit the Jack pot yesterday, went to Mountain Equipment Coop to get a new bike helmet, asked at the service desk if they had used tent poles, guy comes out with two hand fulls of tent poles. One hand is 9mm and the second hand has 11mm aluminum. So I took the 11mm to build a new IOM mast. So my question is do I glue the pieces together to get a little of the play between masts out? leave it as is or use a little electrical tape to keep them together? If glue was an option what should I use? thick CA? 5 min epoxy? or use the Metal epoxy that is also sold at hardware store. Or somthing a little flexable, like goop or silicone?

Yes so many options but if anyone can help it is the people that follow this forum.

thank you in advance

Hi Andrew
I’d use epoxy. Try to come up with some kind of jig to hold them straight. A piece of angle iron or a corner somewhere in the house. I’m looking at a door frame that looks pretty good. When it’s set, roll it on a flat surface to see how much bend there is and mark it so it can go for and aft. Avoid side bend, it puts all kinds of weird wrinkles in your sails.

Don, have you ever used the epoxy that claimes to be able to work with metal? or JB weld which is an epoxy that is use in the automotive industry?

JB Weld works OK - it can be smoothed by using a “wet” finger, shaped, drilled, etc. - but unless you have a serious gap betwen two mast sections, I would not use it. Too heavy and who needs “metal” to glue two pieces together?

Epoxy can also be thickened to fill gaps if that is what you need, but if tolerances between the two are small, I would stuff a piece of tissue into one tube end, push it down as far as needed, and then fill with epoxy. Push the other portion into the epoxy filled tube, wipe off any excess that runs out, wrap with plastic packaging tape and follow Don’s suggestion of using a chunk of angle iron to assure it is “somewhat” straight.

If using WEST epoxy - just scuff up any metal with coarse sandpaper for a bit of “tooth”.

Also, Google “GOODWINDS” kites - they sell a lot of different size aluminum, fiberglass and carbon ferrules that might fit your need.


No, I’ve never used them and what Dick said. Since this is an existing mechanical joint that you just want to support, anything would work. With epoxy if you ever want to take it apart you just apply a little heat and pull.
Do you know what the wall thickness is? Any tent poles I’ve seen are thin walled so I question the stiffness. Do you have a “real IOM Mast” to compare it with? You may be on to an easy souce if they measure up. I wonder if there is a standard test for mast stiffness. Something like cantilevering it off a workbench and hanging a can of tomato soup off the end and measuring the deflection. That doesn’t sound vague enough for IOM rules does it?:devil3::devil3:

I just did one of the masts that a lot of us out here use. I clamped the mast to my bench with a meter of it hanging over the edge. In my case the tip was 83 cm from the floor. I set a can of “Cream of Brocolli” (didn’t have tomato) on the end and it bent down 4.2 cm. For those that are sticklers for details I used a 284 ml can which weighs 347 grams. When you have yours glued up give it a test and report back here please. Please use 5 min epoxy, I’m an impatient man;):wink:

OK, John pointed me at this
I should have figured that Lester had already done this. I don’t know how I missed it, I’ve read his site many times. The method is the same as what I suggested but the weight is 300 grams. Our masts deflect 39 mm which is quite good compared with his list.


I am sorry you need to know right away, I am at work so will try to test tonight, with out glue then will glue them together next week after the long weekend of camping and report back to you. The thickness of the wall I can not confirm but it would look to be in the1-2mm range? This is a grat source, considering it is free. I did experiment earlier in the year with 9mm mast (tent poles as well), it was like a wet noodle, but worked great, spilled of in the gusts, and had an easy time shaping it to the sail with the mast ram. I do not have a real IOM mast to compare to? The other thing I have seen and maybe you will check it out is at MEC (mountain equipment coop) they have the avalanche probe’s Same as tent poles aluminum with farells and you just put them together. Will update when I can.

Oh the thinner 9mm tent poles work great for booms, a little stiffer than arrow shafts.



to “build up” a mast joining halves of your 11mm poles I will ask at the shop for one 9mm pole and check if its O.D. fits the ineer diameter of the 11mm one. If so. just a pice of 4 inches will be more than enought to join togeteher both havles of the 11 mm mast, even using only cyano glue . I did it with my very first mast 2 years ago, that was 12mm thick and at the interior received a 10 mm tube reinforcement, 10 cms. long, I just cyanoed thogether and never had a problem until I solfd the boat. The funny thing is that the first time I just glued the inner tube to one halve and i was able to split the mast in two requiring a small tube to place the whole rig inside.

Hope to be usefull

Tato Lazo


The pieces come with joiners already in them, One end is glued at the factory, the other end is loose so you can take them appart. each piece is almost 2’ long. and the joiner is 100mm long. I thought CA glue would work as well.


Hi Andrew:
Yes , the cyano works well if the tube and the joiner fits is acceptable, if they are loose, then epoxy is the best.



Had some time to test mast. Can of soup same size but cream of mushroom. mast deflecte 5.3cm. probably a little soft but maybe with pre bend will be good, then spill of in the gusts?

your thoughts??

Hi Andrew
Actually it seems to compare quite favourably with the Sails Etc 11mm round. Since you’re using a can of soup at 347 grams and Lester was using 300 you would get more deflection. My 6 foot blanks weigh 157 grams, your’s may be lighter and thats a good thing. You bought one of the Can Tire scales didn’t you? As to spilling in the gusts, I haven’t really thought about that much. It seems to me that that could be controlled with shroud height.
Sounds like a find to me. How straight did you get the join?

Don, I will weigh the mast one I get back into the garage, yes with my canadian tire scale (wonderfull tool) and report back soon.


Don, 154g for mast cut to size for A rig.

how to ?good question .how to forget someone?