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Rich Jones
04-18-2013, 07:38 AM
Not that I'm ready for it yet, but I'm searching for suitable wood for the mast of the HV 13 that I'm building. It's an unstayed sprit rig, mast 3" in diameter at the base and just under 11' in length. Not a huge mast by any measure. Sitka spruce would be best, but I don't want to drive 300 miles to get it. Available around here is what they call 'eastern' spruce. It's the stuff they use around here for framing material. Would it be suitable for a small mast like I need? If I find a couple of dry,straight grained 2x4's, could I laminate them together for a mast. Or, rip them down to smaller dimensions and laminate them together for a stronger spar?
Doug fir would be good also, but is not available around here either.
On the other hand, I was surprised to find a good source locally for cherry, white oak, ash and hondurus mahogany for my other boatbuilding needs.

Mrleft8
04-18-2013, 07:53 AM
Black Spruce. It's local lumberyard Spruce around here (and in VT). It has nearly identical properties as Sitka, it just doesn't get anywhere near as big. I picked up a couple of pieces last fall 8/4X12"X12' for $30 One was nearly clear, the other had some small tight knots that were easy to work around.

JimD
04-18-2013, 08:41 AM
Last year I made a Q&D 12 foot long x 3" diameter solid mast by gluing 2 lumber yard 2x4s together and shaping them. The spar seems to be working just fine. Slapped a coat of cetol on it to give it some colour. Total cost couldn't have been more than $15 and a few hours work.

http://im1.shutterfly.com/media/47a2d938b3127ccef0f3f54c122400000030O00CbOGrVu4cMQ e3nw8/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

http://im1.shutterfly.com/media/47a2d902b3127ccef0fba03bbe1f00000060O10CbOGrVu4cMQ e3nw8/cC/f%3D0/ps%3D50/r%3D1/rx%3D550/ry%3D400/http://im1.shutterfly.com/media/47a2d902b3127ccef0fa1e6f1f6800000060O10CbOGrVu4cMQ e3nw8/cC/f%3D0/ps%3D50/r%3D1/rx%3D550/ry%3D400/

http://im1.shutterfly.com/media/47a2d906b3127ccef0e351ff9ced00000030O00CbOGrVu4cMQ e3nw8/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

Thorne
04-18-2013, 08:57 AM
Check with Eric (or an official wood reference) to confirm the comparable properties of Black Spruce, as this info determines the dimensions of the mast diameter. Gluing two 2x4's works just fine, use a quality slow-cure epoxy with thickener and don't over-clamp. Unless the plans say otherwise, I've had good luck building masts like this with the glue line running fore and aft -- as you want your mast to flex sideways more than the other directions.

Rich Jones
04-18-2013, 10:41 AM
Check with Eric (or an official wood reference) to confirm the comparable properties of Black Spruce, as this info determines the dimensions of the mast diameter. Gluing two 2x4's works just fine, use a quality slow-cure epoxy with thickener and don't over-clamp. Unless the plans say otherwise, I've had good luck building masts like this with the glue line running fore and aft -- as you want your mast to flex sideways more than the other directions.

Eric's plans call for Sitka spruce for both mast and sprit. I was thinking of increasing the mast diamater by one-half inch just to be on the safe side. I was also thinking along the lines of your suggestion about keeping the glue line running fore and aft.
So far, the answers I'm getting here are encouraging.

Gib Etheridge
04-18-2013, 11:25 AM
The local spruce will be just fine. It's convenient that you don't need it right away, you have time to go to a local sawmill and ask them to pull out 4 of clear, free of sapwood, free of heart center and free of sapwood 1 x 4s. 1" will dry much sooner than 2". They should all have the same grain orientation, if possible. When you get them home thickness plane them to 7/8, they'll season a little bit sooner that way.

andykane
04-18-2013, 12:59 PM
Sitka spruce isn't overly strong, just strong for it's weight. I suspect adding half an inch to the diameter would be overkill. In the same material that would increase strength by 85% (ie nearly double).

Mrleft8
04-18-2013, 01:05 PM
Bah! Glue em up with TB2 straight out of the lumberyard (not the mill), after you run them through a planer to get past the oxidized surfaces. The stuff dries so fast that any checking or twisting will have been done in the kiln, or over the winter.
No need to boost your diameter. It has nearly identical properties as Sitka.
On an unstayed mast more of your flex is likely to be lateral anyway, but I don't think there's going to be an issue no matter what orientation you use for your glue line.

Mrleft8
04-18-2013, 01:10 PM
BTW.... The first mast I glued up for The Marjie B., I very carefully cut 10" too short. So I had a laminated 3" square 10' 2" post...... Or beam...... I put it up in the rafters of the garage, and the Marjie B. now hangs from two lag hooks screwed into it..... No sag. It's strong.

Gib Etheridge
04-18-2013, 02:12 PM
BAH! If you get them from the lumberyard they will be net 1.5". Once you plane them clean for gluing you won't net 3". Actually, that probably won't matter. I just wanted to say "BAH!".

It has been my experience though that of all of the eastern softwoods the one that is most likely to twist as it dries is spruce, so if you can find it already dry at the lumberyard or the mill you will be able to pick some that isn't twisted and isn't going to twist.

I think that a lot of the "King's Pine" was actually eastern spruce, destined to be masts and spars.

I, too, would go with the Titebond.

Eddiebou
04-18-2013, 02:28 PM
Here's my 2 cnts worth. I've used lumberyard spruce for several laminations. Rather than look for 2x4's, look at the 2x12's. You can often find a a single board that will yield 2 nice qtr sawn or vert grain pieces with no heart or pith. You can rough cut them to your taper before glue-up. If you only need the extra width near the partners, you might be able to simply cut a long tapered sliver and glue it in between the other 2 pieces. My local lumber yard stocks 2x12 / 2x10 spruce up to 20' long. It takes a bigger (better) tree to get this stuff out than a 2x4.

Mrleft8
04-18-2013, 03:07 PM
BAH! If you get them from the lumberyard they will be net 1.5". Once you plane them clean for gluing you won't net 3". Actually, that probably won't matter. I just wanted to say "BAH!".

It has been my experience though that of all of the eastern softwoods the one that is most likely to twist as it dries is spruce, so if you can find it already dry at the lumberyard or the mill you will be able to pick some that isn't twisted and isn't going to twist.

I think that a lot of the "King's Pine" was actually eastern spruce, destined to be masts and spars.

I, too, would go with the Titebond.
BAH! Around here the local Spruce is sold rough, not s4s! :D

rob
04-18-2013, 04:44 PM
As said, local dimaensional spruce from the building supply is fine/perfect.

Don't waste time digging through the 2X4's, go straight to the 2X12, the long ones. They come out of far better trees and you will be able to find some nice clear sections and edges that can be cut out and glued up for your sticks. Just watch out for the stray hemlock boards that slip in.....they are the ones that wiegh twice as much.

Gib Etheridge
04-18-2013, 04:47 PM
Your lumberyard sells rough spruce? The sawmill, of course, but the lumber yard? Coming from anyone else I'd call that Humbug!

StevenBauer
04-18-2013, 04:57 PM
Have you looked in to birdsmouth construction for this little mast? It would be faster and easier than gluing up two pieces, then tapering them and rounding them.



Steven

Rich Jones
04-18-2013, 06:07 PM
Have you looked in to birdsmouth construction for this little mast? It would be faster and easier than gluing up two pieces, then tapering them and rounding them.



Steven

I'm one for doing things the hard way. I love my hand planes! For a mast this small, a solid one will do fine.
But, thanks for the suggestion.

BobW
04-18-2013, 06:51 PM
Have you looked in to birdsmouth construction for this little mast? It would be faster and easier than gluing up two pieces, then tapering them and rounding them.



I'd appreciate hearing how the birdsmouth construction is an easier and faster method to build a small mast.

The milling of the birdsmouth staves, particularly for a small mast, strikes me as being fiddly - let alone the tapering. The glue-up seems, to me, to be messy although I haven't tried the method. Yes, I've read about building birdsmouth masts, seen videos, talked with folks who build and love them, and admire the end result. But I don't get the "faster and easier" part.

I don't have a table saw so that may be influencing my thinking. I do have a router table but I'm leery of running such small bits through the router. (I know it is done but it still makes me leery.)

So, what am I missing?

Bob Wessel
Fenwick, MI
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

JimConlin
04-18-2013, 07:26 PM
Your lumberyard sells rough spruce? The sawmill, of course, but the lumber yard? Coming from anyone else I'd call that Humbug!
'Tis true.
My local (real) lumber yards have traditionally sold rough spruce 1x8x16' ('ledger boards') and 2x12x16' ('staging planks'). I've bought the 1x8's recently. They're cheap, ungraded and pond wet.

StevenBauer
04-18-2013, 08:09 PM
I'd appreciate hearing how the birdsmouth construction is an easier and faster method to build a small mast.



So, what am I missing?

Bob Wessel
Fenwick, MI
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff


The tablesaw, I guess.

When I built the rig with my son for his ELF we wanted to make the yard hollow but the boom solid. They both had a taper at each end. They were pretty similar in size.

I didn't need to glue anything up for the boom, we had some spruce large enough. First we squared it up and ripped it to size. Then we had to lay out the tapers on the square blank. We made a centerline, marked out the stations on two sides on both ends then measured half the mast thickness at each station and marked the station there. Then we connected these marks with a batten. We cut just wide of these four lines(both ends) on the bandsaw then planed to the lines. Then we repeated the whole process on the other two sides. So now we had a square stick with the proper taper at both ends. Next we made a spar gauge and marked the spar out for eight siding. We planed to the marks and had an eight sided tapered piece. I'll stop here and bring the Birdsmouth to the same stage.

We calculated the size we needed for the staves and ripped them to size on the tablesaw. Two passes each. We tilted the blade to 45 degrees and ripped the Birdsmouth. Again, two passes each. Then we made a simple taper jig, just a piece of 3/4" plywood about 6" wide as long as the longest taper. We screwed a fence to the plywood so that the amount of wood we wanted removed from the stave hung over the side of the plywood. A couple of small blocks of wood screwed to the fence held the stave in place. The tablesaw fence is set to the width of the plywood and each stave is quickly run through the saw. Then you reset the jig for the other ends taper and run each stave through again. Not much is really removed from each stave, just a sliver, really. And the staves are now ready to be glued up. You lay them side by side with the Birdsmouth up (holds the glue that way) and spread them with glue. We used GelMagic so no adding thickeners or pre wetting out. They are self aligning and pretty much snap right together but it does help to have two pairs of hands. A dozen or so cheap hose clamps and some cable ties and the glueup is done. The next day you take off the clamps and plane off the eight little corners that stick out from the Birdsmouth. Now you are at the same stage I left the boom. Eight sided and tapered at both ends. It took longer to write it out but I can attest when you do one of each a day apart it is noticeable how much less work the Birdsmouth one was.


Steven

Pete E
04-18-2013, 09:34 PM
Another way for making a mast that you also need a table saw.

Duckworks - Making a Coopers Mast (http://www.duckworksmagazine.com/11/howto/mast/index.htm)

David G
04-18-2013, 09:41 PM
Another way for making a mast that you also need a table saw.

Duckworks - Making a Coopers Mast (http://www.duckworksmagazine.com/11/howto/mast/index.htm)

Well... that IS one way to go about it. Though Andy is a sterling fellow - a friend, and fellow Coot - I'd rate it inferior to all the other methods that have been discussed.

Mrleft8
04-19-2013, 07:07 AM
I'd appreciate hearing how the birdsmouth construction is an easier and faster method to build a small mast.


Bob Wessel
Fenwick, MI
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff
I'm guessing that Steven was joking.

BobW
04-19-2013, 08:40 AM
The tablesaw, I guess.
...It took longer to write it out but I can attest when you do one of each a day apart it is noticeable how much less work the Birdsmouth one was.


Steven

Thanks for the explanation. I do appreciate it. I realize there is at least one other item I lack... the extra pair of hands.

After reading your explanation it occurred to me we all have our own perspective of what is "faster and easier" and what is "fiddly." Right now, for me, the birdsmouth method seems more fiddly than tapering and rounding a solid (or hollow) square section blank into a spar. And what that means to me is the birdsmouth method isn't faster and easier. Perhaps, if I find the time, tools and extra hands, I'll try a birdsmouth spar to see for myself what it's all about.

Thanks again for the explanation.

Bob Wessel
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

okawbow
04-19-2013, 09:27 AM
For a mast that short; why not laminate 4 clear fir trim boards? The result would be strong enough to leave a little smaller in diameter, and could end up about the same weight as spruce.

Mrleft8
04-19-2013, 01:25 PM
For a mast that short; why not laminate 4 clear fir trim boards? The result would be strong enough to leave a little smaller in diameter, and could end up about the same weight as spruce.

Black Spruce is local in VT..... Douglas Fir is local in British Columbia.... ;)

okawbow
04-19-2013, 02:07 PM
Black Spruce is local in VT..... Douglas Fir is local in British Columbia.... ;)
Clear fir is readily available in the Midwest. Is it not available in the East?

StevenBauer
04-19-2013, 05:10 PM
I'm guessing that Steven was joking.


???
No joke. Easier, faster and less fiddly. And more forgiving of less then perfect materials.

Chip-skiff
04-19-2013, 06:30 PM
For a 13 ft. mast for a balance lug sail on a 15 ft. skiff, I cut a standing dead lodgepole pine in the forest near my house. Since lodgepole (pinus contorta) has a very slight natural taper, all I had to do was take off the bark with a drawknife and do a bit of sanding.

It's proven strong enough during two seasons of sailing in Wyoming, and I enjoyed using local timber. The skiff is plywood, so I'm not a purist by any means.

Rich Jones
04-19-2013, 06:48 PM
Clear fir is readily available in the Midwest. Is it not available in the East?woods.

No so much around here. Very loose building codes allow for cheaper wood.
When I lived on Long Island, N.Y. the building codes demanded doug fir for framing.
I'll head to the lumber yard next week and look for a good spruce 2x12.

BobW
04-20-2013, 07:23 AM
I am trying to sort out how I might be able to try my hand at building a bird-mouth spar. I may have access to a friend's table saw and assistance.

Steven, something I didn't see in your birdsmouth assembly sequence is the plugs/spacers. How are those cut those and when are they added to the spar?

Thanks.

Bob Wessel
Fenwick, MI
Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

davebrown
04-20-2013, 03:35 PM
Bob: I think the accepted sequence (and this is how I did it) is you glue up the mast with tape along a pair of opposite edges, so that when the first run dries, you have the effect of a clam shell that you can open back up. You then put in your plugs and spacers, etc.. At that point I suppose you could let one side dry in, and then close the whole thing up with slurry in the seam, but in my case I did it with only one step: slurry all sides of the plugs, lay a bead in the two unglued seams, and then re-clamp everything just like the day before with the other seams. It's messy but easy to do. I did that on the mizzen for my coquina, which was only a ten foot mast and not necessary. I did it to learn how. On the mainmast I did a 1x4 glue up wth spuce and then chopped out a channel to make it hollow. That was not fun, and took five times as much time. I would not do a hollow mast again that way when birdsmouth is an option. When my father was out a few months ago we cut the 20 ft staves for my next build, and it was quick and effective. THen I had the staves laying on the boat carriage while I was moving a floor machine around and clumsily caught a toe against something and snapped one fo the staves--a big ugly fracture that was too long to scarf out. I have the now seven staves leaning against my foyer since Thanksgiving, which delights my mother-in-law. I will have to do a glue up or run across another twenty footer to finish.

https://sphotos-a.xx.fbcdn.net/hphotos-ash3/601815_10200510693642338_1628954125_n.jpg

BobW
04-20-2013, 05:57 PM
Thanks, Dave,

I think I understand the sequence now - except for the cutting of the plugs.

Talking with a friend who has a table saw about recruiting his assistance ripping the staves for the 14' mizzen mast for my Pathfinder build. I can take 14' lumber to his place and bring the staves back with the Volvo. I am also thinking of using my router table to cut the bird-mouth notches although we'll probably experiment with the table saw, too.

Gluing up a blank by sandwiching two narrow staves between two wider staves creates a hollow blank isn't too difficult. The work comes from rounding the blank into a round mast.

The logistics of getting a saw to my place or the (recently acquired) 20' DF for the main mast to a saw will be a challenge. I don't need to solve that issue just yet.

Your wood storage area is much more elegant than mine. :)

Bob Wessel
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

davebrown
04-20-2013, 06:14 PM
I got boatbuilding wood stored all over the house Bob. You ought to see the western red cedar I have in the master bedroom.

JimConlin
04-20-2013, 06:44 PM
Clear fir is readily available in the Midwest. Is it not available in the East?
Yards in my area sell clear VG douglas fir in 1x4 decking, 2x6 and sometimes 4x4.

BobW
04-20-2013, 07:15 PM
I got boatbuilding wood stored all over the house Bob. You ought to see the western red cedar I have in the master bedroom.

That must help keep the shop less cluttered!

Bob Wessel
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

StevenBauer
04-20-2013, 10:04 PM
Thanks, Dave,

I think I understand the sequence now - except for the cutting of the plugs.

Talking with a friend who has a table saw about recruiting his assistance ripping the staves for the 14' mizzen mast for my Pathfinder build. I can take 14' lumber to his place and bring the staves back with the Volvo. I am also thinking of using my router table to cut the bird-mouth notches although we'll probably experiment with the table saw, too.

Gluing up a blank by sandwiching two narrow staves between two wider staves creates a hollow blank isn't too difficult. The work comes from rounding the blank into a round mast.

The logistics of getting a saw to my place or the (recently acquired) 20' DF for the main mast to a saw will be a challenge. I don't need to solve that issue just yet.

Your wood storage area is much more elegant than mine. :)

Bob Wessel
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

The plugs are an interesting topic. I've done it 3 or 4 ways. On one I just drilled the ends to round a few inches deep and glued 3" long dowels as plugs for the ends. There is no solid blocking at the partners. 10 years old, no worries. On another I did the same but drilled in about a foot and glued in a long plug with a tapered top to minimize stress there. That plug went up past the partners. The top of that mast had a long plug at the top and had a sheave in it. For a more substantial plug I've not tapered the bottom of the staves, this left the hole inside the bottom of the mast as more of a cylinder than a cone and I could glue in a longer piece, also with a tapered top. Then I cut the taper at the bottom of the mast afterwards with handplanes. Dave's method is good, too for a mast that needs special blocking, like for a gaff rig.




Yards in my area sell clear VG douglas fir in 1x4 decking, 2x6 and sometimes 4x4.

We can get nice vg fir, too, but it's very expensive.


Steven

BobW
04-21-2013, 09:00 AM
Thanks, Steven, for the added info.

I'm looking forward to trying the birds-mouth method and comparing it to rounding out a spar from a square blank. My first efforts at a birds-mouth spar will have to wait a week or so as I will be away from my shop.

Bob Wessel
Fenwick, MI
Building Gardens of Fenwick, a Welsford Pathfinder
Karen Ann, a Storer Goat Island Skiff

ahp
04-21-2013, 01:43 PM
Boulter Plywood in Summerville, MA has Sitca Spruce. They deliver.

Eric Hvalsoe
04-21-2013, 03:49 PM
Of course I'm going to specify Sitka spruce, being from the pacific northwest. But I also imagine, as has been suggested, something workable can be found at the local construction lumberyard. I'm not an authority on the various spruce species, or what's laying around lumberyards in Maine. There are some varieties of inexpensive spruce in our local yards - maybe in a pinch. Any blue stain should jump right out. It is only a small mast, but less weight really is a great convenience - Doug fir is surprisingly heavier than Sitka spruce. I've known guys to cut a perfectly good fir 4x in half, hollow, and reglue to save some weight. Birdsmouth is cool but not likely a significant labor savings, at least first time around. Really not a huge weight savings either. Whatever you use, hard to imagine more tha 3 inches necessary at partner. If concerned about stiffness you could moderate the taper. Some flex is good to spill a bit of wind, on the other hand if you've got a really bendy mast you'll never be able to tension the wrinkle out with the sprit yard. Yes the bending force is primarily lateral. I like the long grain of these softwoods for this application.
Eric

Mrleft8
04-22-2013, 07:18 AM
Common Name(s): Black Spruce

Scientific Name: Picea mariana

Distribution: Northern North America

Tree Size: 30-50 ft (10-15 m) tall, 1-1.5 ft (.3-.5 m) trunk diameter

Average Dried Weight: 30 lbs/ft3 (480 kg/m3)

Specific Gravity (Basic, 12% MC): .38, .48

Janka Hardness: 520 lbf (2,320 N)

Modulus of Rupture: 10,800 lbf/in2 (74.5 MPa)

Elastic Modulus: 1,610,000 lbf/in2 (11.10 GPa)

Crushing Strength: 5,960 lbf/in2 (41.1 MPa)

Shrinkage: Radial: 4.1%, Tangential: 6.8%, Volumetric: 11.3%, T/R Ratio: 1.7


Common Name(s): Sitka Spruce

Scientific Name: Picea sitchensis

Distribution: Northwestern North America

Tree Size: 160 ft (50 m) tall, 5 ft (1.5 m) trunk diameter

Average Dried Weight: 28 lbs/ft3 (455 kg/m3)

Specific Gravity (Basic, 12% MC): .36, .46

Janka Hardness: 510 lbf (2,270 N)

Modulus of Rupture: 10,150 lbf/in2 (70.0 MPa)

Elastic Modulus: 1,600,000 lbf/in2 (11.03 GPa)

Crushing Strength: 5,610 lbf/in2 (38.7 MPa)

Shrinkage: Radial: 4.3%, Tangential: 7.5%, Volumetric: 11.5%, T/R Ratio: 1.7

rregge
04-22-2013, 01:25 PM
I have a stash of aircraft grade 4" x 4" x 16' spruce that was cut down around 1960 and stored until I picked it up a couple of years ago. Straight as an arrow, 30-40 rings per inch. Sorry I am not closer (west of Boston).