Malahini construction questions

Designs for inboard or outboard power

Moderator: BruceDow

Post Reply
obd
Posts: 57
Joined: Sun Dec 30, 2012 3:39 pm
Location: Mount Pleasant, SC

Malahini construction questions

Post by obd » Tue Nov 19, 2013 12:49 pm

I am currently fabricating breasthook and chine blocking. 2 questions: 1. I am having trouble getting sharp right angles when cutting the notch in the breasthook and the chine blocking. I know that i will be cutting numerous notches in the future when fitting the battens. Any advice on simplest way to cut accurate, clean 90 degree notches. I am thinking a keyhole saw might do the trick to take the tiny radius out of the right angle. If the answer to this question involves the use of a router, could someone describe in a little detail how this is done(still a newbie when it comes to router use) 2. When i dry fitted the chine blocking and breasthook to the stem, it was not as snug as i thought it should be. I think this is due to the plywood being metric and the plans calling for 2 lams of 3/4 inch for the stem, thusly my stem thickness is ever so shy of the 1.5 inch notch width. Is this a big deal? will epoxy take care of this? I have enough left over plywood to cut new chine and breasthook but thought I would ask first. As always, I thank you guys for the way you generously share your wealth of knowledge and experience. Bob

User avatar
jprice
Posts: 687
Joined: Sun Aug 28, 2011 11:59 am
Location: Marietta, GA

Re: Malahini construction questions

Post by jprice » Tue Nov 19, 2013 1:50 pm

I'm not sure what breasthook notch you're talking about. If you're talking about the part where the stem goes in, I actually cut that out using a jigsaw prior to assembling the 2 layers of the breasthook.
Some pics of what you're working on might help here.

As far as the small gap is concerned, that's actually a good thing. Thickened epoxy in there will form a good strong joint. Epoxy is much stronger that way than with a very tight joint.

User avatar
Roberta
Posts: 6431
Joined: Tue Jul 31, 2007 5:23 pm
Location: East Troy, Wisconsin

Re: Malahini construction questions

Post by Roberta » Tue Nov 19, 2013 2:33 pm

That's one of those "gotcha" things when using the patterns and the laminations are not as thick as the notch measurement on the pattern. As long as the gap is not too sloppy as to create an alignment problem the glue will fill the gap just fine. You could also shim with a thin cut of wood if the joint is overly sloppy. It's a wood boat and most any misteaks can be fixed. :D

Go to Ace Hardware or some wood working store and get a Japanese pull saw. These are great for cutting notches for chines, battens, and shears. Multiple cuts to the correct depth and angle(s) can then be broken out with a screw driver and cleaned up with a sharp chisel, file and sandpaper. I prefer to notch this way. Pre-notching may not always work out well and they might not line up as well as anticipated.

Roberta :D :D :D
Roberta "Queen of the Boat Builders"
Built Zip "Oliver IV", Super Spartan "Jimmy 70", and Torpedo "The Glen L".

John56
Posts: 106
Joined: Fri Jun 21, 2013 2:09 pm
Location: South Georgia
Contact:

Re: Malahini construction questions

Post by John56 » Tue Nov 19, 2013 4:21 pm

Roberta Hegy wrote:That's one of those "gotcha" things when using the patterns and the laminations are not as thick as the notch measurement on the pattern. As long as the gap is not too sloppy as to create an alignment problem the glue will fill the gap just fine. You could also shim with a thin cut of wood if the joint is overly sloppy. It's a wood boat and most any misteaks can be fixed. :D

Go to Ace Hardware or some wood working store and get a Japanese pull saw. These are great for cutting notches for chines, battens, and shears. Multiple cuts to the correct depth and angle(s) can then be broken out with a screw driver and cleaned up with a sharp chisel, file and sandpaper. I prefer to notch this way. Pre-notching may not always work out well and they might not line up as well as anticipated.

Roberta :D :D :D

Great tip!! I'm very close to notching my Barrelback frames and was wondering best way to it also. I have routers, but routing vertically straddling a boat form was not something I was looking forward to.

Post Reply

Return to “Power Boats”