PDA

View Full Version : Tiller repair & spar construction



cs
05-22-2002, 09:39 PM
First tiller repair. This is kinda like asking forgiveness and not permision since I already done it. If you remeber on my first sail of the season my tiller broke. The wood split right where the pin goes through. Well I cut the tiller a little shorter and redrilled my hole, but than I went one step further. I wrapped the tiller (where the pin goes) with 4" wide fiberglass tape and set it in epoxy. What do you think? Will this help with the shear forces?

Second about making spars. Now don't know how many of you folks out there make your own, but I do and I kinda like it. Now I've only made 3 so far and here is my question. How many of you worry about making it perfectly round? I don't do the birdsmouth. I make mine out of solid material and rip the corners and than hand plane and sand. I don't end up with a "perfect" round spar, but it is close enough for me. How close do you get before calling it good?

Chad

cs
05-23-2002, 12:44 PM
Maybe this got lost in the shuffle so I will pull it up to the top and try again.

Chad

Art Read
05-23-2002, 01:32 PM
Haven't made my spars yet, but I'm starting to think about it a lot while sitting in the moaning chair. I'll let you know my "opinion" on your question after I see the results of my efforts...
However, like everything else on the project so far, I suspect when it "looks" right, it will be.

mmd
05-23-2002, 01:33 PM
Tiller repair - the 'glass & epoxy will certainly strengthen the tiller shaft. If it shows signs of failing again, consider putting 1/8" bronze "cheeks" on each side of the tiller so the loads are distributed over a wider area than just the pin.

Sparmaking - solid round is "the old way" and perfectly acceptable. As far as being perfectly round, if it looks eye-sweet and feels smooth & round, it is done. It really depends on the style & finish of the boat it's on - a traditional workboat quality sailing dory looks quite fine with spars that have lumps & bumps, but a Herreshoff 12-1/2 needs near perfection or it'll look like a wart on a pretty girl's face.

Chadd Hamilton
05-23-2002, 01:49 PM
Hey Chad- I made my first spar this past winter for my Acorn. It's a birds-mouth style spar, but with no taper. No matter how much planing and sanding I did, I never managed to get it perfectly round. I finally threw in the towel and just started putting the varnish to it. But like everything I do, it's "close enough".

Are you using Doug Fir?

Wayne Jeffers
05-23-2002, 02:05 PM
As to spars, Chad, I found it surprisingly easy to start with a square section, plane slowly to eight equal sides, then to sixteen equal sides, then smooth over the edges for near-perfect round. The secret, I think, is in working slowly and in checking shape often. Simply rubbing the hand over the work is surprisingly effective in identifying unfair spots.

Wayne

Bill Perkins
05-23-2002, 03:28 PM
Chad if you check the archives you'll find reference to finish sanding spars with an inside out sanding belt . This has given me apparently perfect results ,but the planeing to 16 or 32 sides still has to be accurate .Maybe you should try a longer plane ? I like small solid spars with knots too . SPF !

[ 05-23-2002, 04:39 PM: Message edited by: Bill Perkins ]

John Di Dio
05-23-2002, 03:35 PM
I've made a few small round spars. One technique that worked good for me when doing the final rounding was to take a sanding belt, turn it inside out, stick the spar inside the loop, chuck the rubber core of a sanding drum in an electric drill and use that to get the belt spinning around the spar. Takes a little bit of finesse to get everything balanced, but once you get it going it rounds off the high spots pretty quick. Keep it moving back & forth. If you can get a helper to slowly spin the spar while you sand it works even better. Do the final sanding lengthwise using a longboard.

Ian McColgin
05-23-2002, 04:03 PM
A nice old trick for getting the 8 siding right - and this works on tapered spars and even tapered on three sides (leave the luff straight) is to set up a marking guage that is conveniently a bit longer than the thickest part of the mast. At each end a longish round post so the guage will ride along the blank. The guage has been divided into 17 convient parts with 2 prickers through to divide it 5 - 7 - 5.

Say your blank is 3" square at the thickest but there's some taper. You might make the distance between the posts 3-3/16" (51/16") so you can make 3/16th divisions. Lay the scribe across at the angle it takes ans scribe away. Gives you what to plane to.

Paul Griffin
05-24-2002, 03:06 PM
I spent 5 hours yesterday rounding my 8 sided 13' boom. I started with my 5 1/4 hand plane, rounded it to 16 sides. Then shaved off all those corners. Then I used a 24" 80 grit belt sander's belt that I cut open and finished sanding it by hand. Lots of hand work, but it feels so good. Now to do my 9' gaff and 20' mast.

Paul

JodyAdamonis
05-24-2002, 11:06 PM
It must be spar making season. I made my spars last night for my Shellback, which I planed on finishing in March. For the most part thing went according to plan using the 8 to 16 sided method and then switching to a block plane to finish it off the remaining corners. From there I turned to 60 grit sand paper and progressively worked my way up to 150. One alternative method that I thought made the whole process move along faster is using a power planer to remove the meat of the material. When it first started, I tried hogging off material with a wll tuned #4 stanley but found the sitka required too much brute force for how much work I had in front of me.

One problem that I did run into though was when I was cutting the plank for one of my spar to the rough dimension it came out the other end of the table saw all twisted and warped even though I edge planed two sides before cutting. This was a costly problem. Oh well, at least it was on the yard and not the mast. good luck in making your spars and practive on a nice piece of SPF prior to digging into your good wood.

Nick Kent
05-25-2002, 01:05 AM
I was in a spar shop this past winter and had the opportunity to build a 45 foot boom for the schooner Sylvina Beal. We roughly squared the log with a circular saw that had a chain saw bar and chain on it. then further squared it with a power plane. After all four sides were square and the taper was fair, we went to eight sides. used the marking tool with two pencils (forget the correct name). It gives a good fair even line to saw along. then rough cut eighths with a circular saw. I then faired the eight sides with the power plane very carefully. After the eight we went to sixteen sides using the power plane. After sixteen sides, we went to 32 sides using the power plane and then hand planed the 32 sides round. After it was rounded with the hand plane I hand sanded it smooth with 60 grit. then varnish and out the door. It's really cool seeing the thing take shape. when you do your primary squaring off with four sides make sure that they are very square, and even, then all the steps after that will go smoothly. when going to eighths and sixteenths make sure that all sides are equal dimensions depending on diameter of the spar, and it should come out round as can be. Also, it helps to go to as many even sides as possible. 64ths if possible.

[ 05-25-2002, 02:10 AM: Message edited by: Nick Kent ]