Hello again! I’m making slow progress on a toy boat for my 4 year old son. I started with the bob-about plans, and took the top and side views from the “general layout” sheet. I got some pieces of wood cut out, surfaces trued, and they’re gluing up right now at the shop. Tomorrow I’m planning to trace the side view onto the side of the block (the top view is already on the top) and attack it with a bandsaw. This will give me a chunk of solid-oak shaped vaguely like a bob-about. I may even go so far as to trace the bottom panel (if I can ever get it printed out full scale) onto the bottom of the boat and attack it with the belt sander to make it truly bob-about shaped.
So – if I put a mast and a keel on this bad boy can I expect it to sail at all? I’m not looking for stellar performance, my son will be delighted if it moves at all. We’re planning to put a 20-30 foot piece of string on the bow, set it on a beam reach or somesuch and turn it loose from the edge of the pond. When it gets to the end of the string he’ll pull on it, and hope it tacks :).
He wants one that’s “mote control” and i’ve convinced him that a string on the front is the next best thing
My hope is that we can learn a little bit about how to set the sails to make the boat go in various ways, and have some fun along the way.
He wants a “pirate ship”, and I love gaff-rigged ketches so I’m thinking maybe I’ll try to rig it as a gaff-rigged ketch/schooner and fly a wee little jolly roger from the mast. If it doesn’t work out I can always drill a new hole for a single mast and rig it as a sloop.
My plan for the second boat (or maybe just further treatment to the first boat if it sails really poorly) is to build it the same way, but cut a 1/4" slice off the bottom and top (following the contours of the surface), hollow out the middle piece, and glue it all back together.
Sounds familiar. I accidentally made an 8" Razor when I didn’t check paper size while printing. My 4yo daughter liked it so I finished it and gave it to her. It’s sailed mostly in the swimming pool but sailed a pond once. We just turned it loose and waited for it to come back near shore.
The rig I put on it is a balance lugger. I guess it could be considered pirate-like.
Performance of it was great. My radio controlled full 12" Razor couldn’t catch her. If only she’d stay on course.:lol:
Martin Roberts, who is (or was recently) the world Marblehead Champion, has a son of about the age og yours. Mother is also a model yachting nut - and very good in her own right. The son will not be allowed near a radio until he can set his BUG up to sail with perfect balance as a classic feee-sailing model. Go with it: it will teach him a lot.
:zbeer:
Thanks for the input, guys. Flavio, that’s a gorgeous little boat! I’m afraid mine’s going to pale in comparison. I did get it cut out today… the little bandsaw didn’t like cutting through 4" of oak, but the big bandsaw did the job! Might should have used pine, but hey – the oak was free! I spent some time at the belt sander and now I’ve got a chunk of oak shaped vaguely like a Bob-About that won’t give me splinters :).
I want to sand it some more to get rid of the sharp edges, and maybe find a finer grit belt, but shortly here it’s going to be time to drill holes for the masts and bowsprit! I saved the bottom piece when I cut the side shape so I can use it as a cradle when drilling.
There are a few pieces of what i think are scrap maple lying around in the shop, I’m going to ask at tonight’s meeting whether they belong to anyone, I’m thinking it might be nice to turn a slightly tapered mast and bowsprit rather than just using a dowel – besides, the maple should make a nice contrast to the oak :). Might be able to use it for the keel as well.
Are there any guidelines for mast and keel placement? I’ve heard that the “center of effort” (basically the geometric center of the sails) should be close to something else (i forget what it’s called) that’s basically the geometric center of the boat below the waterline (including the keel). When making that calculation do you assume the sails are sheeted in completely or that they’re out at some angle?
I drew something out using the “TLAR” approach, but my eye isn’t calibrated so I don’t trust it. I placed the masts at 4" from the stern, and 10" from the stern, with a bowsprit projecting about 4" forward and 2" up. Both sails have a 5" boom, and the jib runs from the top of the foremast to the end of the bowsprit. I drew it with a 12" mast, but I think I’ll want to make the masts taller, and maybe make the rear boom longer?
Any suggestions would be greatly appreciated on this front!
without doubt a model toy built using oak will be really “childrenproof”
Anyway I feel that something a bit lighter ( using fir , pine or cedar ) will be a much better sailer, and almost as robust.
( last but not least a softer wood would be easier to work with )
with reference to sail balance I have two easy suggestions :
1 - try to have geometric center of sail plan “almost” in the same longitudinal position of finkeel center ( no hull, no rudder, - keel only - )
2 - try to insert fin keel in a slot made on hull bottom so to have possibility :
to make small longitudinal adjustment ( less than one inch ) in order to fine tune sail balance.
to change or modify the keel in order to have different ballast weights to suit different wind speeds
Thanks for the extra pictures, Flavio! This is what I’m leaning towards as a sail plan (rear mast 12", forward mast 16") though i might replace the rear gaff-rigged sail with a bermuda…
I also got some new plans from ian dunmore (thanks ian!) so I might try a foam one next :).
If you make a boat from blue or pink insulating foam you can give it a couple quick coats of water-based polyurethane to seal it. Then spray it with enough flat white fast-drying enamel to cover the pink or blue. Now your four year old can “paint” the boat with Sharpie markers. If you use a nice brown Sharpie you can even “plank” it. I usually put another coat of water based polyurethane over the top to seal it but it is not necessary.
