Making a 'Birdsmouth' mast

[Mike]

As I plan to have a go at building a few spars using the 'birdsmouth' technique, I have been doing a bit of research on that fascinating topic. Here's a link to a pretty good blog on the subject by one by the name of 'Simon' of St Petersburg, Florida, USA.


http://planingaround.blogspot.com/

I have to immediately say that I don't like Simon's choice of build - not one little bit - but his birdsmouth mast and his blog is, in my opinion, excellent. Pity the rest of his build won't come up to the same high standard as his mast. That lovely work of artisan skill will undoubtedly be spending a lot more time in the water than it ought to. At least it is likely to provide sufficient buoyancy to ensure the accursed box doesn't turn turtle. :detective:

Nice one Simon - the mast, I mean. :approval:

Best wishes

[George Waite]

Mike
Excellent work but very expensive/demanding way to make a stick! Can see some merit in it for big sticks but for craft less than 70 odd feet?

[Mike]

I don't disagree with you at all, George. The technique seems to have some merit with respect to producing a hollow mast (and thus a tidy conduit for lighting cables, etcetera) and for buoyancy in the event of a knockdown.

It is, as you say, a time consuming and expensive method of spar making. I am considering it for the big'un and not for the TBs. She will not be 70 feet, though. And, since the masts are unstayed, I think solid chunks of timber are called for rather than hollow masts. I will take advice from 'God' on that one and welcome any input from those, like yourself, who know far more about such things than I ever will. ;)

How's that lovely St Pierre Dory coming along? Any progress to report? The weather at present is hardly conducive but I notice the temperature has risen significantly. Where epoxy is concerned, the only likely problem seems to be the old amine blush caused by all the moisture in the air at present. I see there are three flood warnings current for our neck of the woods. How is it down your way?

Regards

[George Waite]

mike
The boatyard is at the moment on stop but I am at my friendly neighbouhood Smithy making the fuel tank and overhauling the salt water cooling pump from the Yanmar. I have been trying to upload some photos to the gallery but with no luck, perhaps they are too big? advice required. As for flooding, my home was waist deep for three years running from 2000-2003. I/ we a small village commitee took on the Environment agency and eventually ended up with a dam. I do not like being told that I have a tidal problem when I am 120 ft above sea level.
George

[Mike]

I have been trying to upload some photos to the gallery but with no luck, perhaps they are too big? advice required.George

Good to know you're pressing on with things. I would love to see some pics. If the pics are jpg, they can be very large without running into snags. However, other formats tend to be somewhat limited in size. If you can't get them up, just fire 'em off to me attached to an email and I'll sort it out for you. When uploaded, you can then edit the pics to add whatever text you want. It doesn't matter whether you load them or I do on your behalf.


As for flooding, my home was waist deep for three years running from 2000-2003. I/ we a small village commitee took on the Environment agency and eventually ended up with a dam. I do not like being told that I have a tidal problem when I am 120 ft above sea level.
GeorgeThat one cracked me up, mate. :rofl: Makes you wonder what kind of people run this country, does it not? The answer appears to be that they hold pretty pieces of paper suggesting they know what they are doing - but they don't know up from down. Attend one of the so-called 'new' universities and you'll quickly catch on to the underlying cause of this phenomena. I know from first hand, and hard earned, experience.:bonk:

Best wishes

[bemm52]

Just found this thread..............I built my Houdini mast and yards using the bird mouth method.............oregon timber 10 rings+ per inch and gorrila glue
A bit of work to rout all the segments but the glue up went pretty easy locked togther with cable ties every six inches or so and SWMBO gloved up lending two hands.
Cheers Paul

[Mike]

.....I built my Houdini mast and yards using the bird mouth method.............oregon timber 10 rings+ per inch and gorrila glue.

A bit of work to rout all the segments but the glue up went pretty easy locked togther with cable ties every six inches or so and SWMBO gloved up lending two hands.
Cheers PaulPaul, did you by any chance take some pics of the build? If so, how about posting a few? You can always leave out the ones with SWMBO if she's shy. I am perfectly happy gazing at my gorgeous Jeannette - but intensely interested in making birdsmouth spars. ;)

[bemm52]

Sorry Mike no pics not sure why I didn't take any..........I used the photos in Barret farrofs navigator build as a guide.......Duckworks also have some excellent articles on bird mouth spars.
Cheers Paul

[Bill Rintala]

Hey Paul,

Duckworks does indeed have a number of goog pieces on the subject.

I'm am currently leaning toward going with birdsmouth masts and spars for my Houdini yawl. What are you specs for the main mast? OD, ID, taper, if any?

Regards,

[bemm52]

Bill your lucky..........I found a mast stave offcut it is 30mmx15mm I routed a V in the 15mm face the mast came out at 3" diameter as per Johns alloy specs.

Yards are both the same at 45mm dia from memory.

There are tables on Duckworks to give you stave sizes Basically they are saying stay within a certain factor range for optimum results.

Tapering is jist a matter of clanping staves togther V side down and planing a bit off all of them (8) togther to get taper I did last 600mm of mast....3"/2"

I cut and scarfed all the dodgy grain and stuff out of staves first though, and staggered scarfs.

I then layed staves out for glueing ..........on the square edge of stave 1 and 5 I put ductape..........too glue I turned them V up in order and applied glue carefull not to glue V in stave 6 and 2..........then the fun starts........ HINT DO A DRY RUN WITH YOUR ASSISTANT INCLUDING CABLE TIE CLAMPING----THEY ARE CHEAP ENOUGH TO WASTE A FEW.......WE FOUND BEST WAY WAS KINDA MASSAGE BUTT END OF MAST TOGTHER THEN APPLY TIE THEN MOVE UP 6or8" AND PUT NEXT TIE ...........

The whole thing kinda snaps togther .........its a satisfing task.

Apply glue and do it for real I used 4 saw horses to support it once its all cable tied togther eyeball it for woofs a bash with a mallet here and there will true it up.

when glue has set cut cable ties and split into two halves where duct tape joint is......... I then cleaned all dry glue ozze from inside mast and epoxied with slightly thickened with a brush

I made a plug (all 8 sided) to fit mast head about 300mm long ...200long for haliyard blocks and about 800mm at base of mast this aslo became knob for mast step.... lay plugs where they need to be slurp glue about put other mast half on top and re cable tie.... eye ball and bash if need be.

external clean up is pretty straight forward.

I may glass outside of mast/ spars saw a duckworks Utube thing on this the other day apparently you can get matt socks to put over mast to do this

Gezz my fingers tired.......... PS raised my seats 3" gives me 10"aprox seat top to floor is this what you got?

Cheers Paul

[Bill Rintala]

Thanks for the info on your birdsmouth mast, Paul.

On the seat tops, mine measure about 9 and 3/4 inches from the top of the false floor to the top of seat top.

Regards,

[Ray Frechette Jr]

I am not too terribly fond of the Birdsmouth method myself.

Best thing I can say for it is it allows you to use up a whole lot of offcuts if you have them.

To the downside it is very time consuming and a goopy slippery mess and you do need to ensure the shaft is dead straight and well supported while curing. Further the placement of secure solid blocking in area of need is awkward and messy to.

From a pro builder perspective I would much rather build a box section mast with triangular cleat on inside corners and square blocking in way of where you need mast solid.

John's Navigator plans feature plans to make hollow mast buy this manner.

Much cleaner and easier to make and the mast is virtually self jigging and self aligning and a pleasure to work in comparison. Downside is that you need larger bits of wood to make it.

Final thickness and weight of mast is the same in the end product