Help needed !

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Nigeb22
Posts: 13
Joined: Mon Jul 01, 2019 1:57 am

Help needed !

Post by Nigeb22 »

Hello all,

I am building a barrelback in Portugal and just starting off feeling my way through the plans
which takes time.
I have been cutting out the bow section 3x lengths of 18mm plywood and the inside has a curve
which now needs to be trimmed back to the line
On the outside its a concave curve and I have a flat wood plane..?
on the side it convex and I don't have anything to trim this

Ok I not know much about this but that's why there's a forum

Can anyone please tell me how to trim this back to a nice curve please

cheers
Nige
Attachments
bow section
bow section

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Roberta
Posts: 7198
Joined: Tue Jul 31, 2007 5:23 pm
Location: East Troy, Wisconsin

Re: Help needed !

Post by Roberta »

Inside curves can be sanded to shape using spindle sanders or sanding drums. Drums can be mounted on drill presses.

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

Hercdrvr
Posts: 1523
Joined: Mon May 11, 2015 12:52 pm
Location: McKinney TX

Re: Help needed !

Post by Hercdrvr »

I use a hand belt sander with very course grit belt to shape parts.
Matt B

TAB
Posts: 191
Joined: Tue Aug 09, 2016 3:22 pm
Location: OR

Re: Help needed !

Post by TAB »

Roberta wrote:
Fri Dec 04, 2020 8:51 am
Inside curves can be sanded to shape using spindle sanders or sanding drums. Drums can be mounted on drill presses.

Roberta
You can even wrap sand paper around a large wood dowel ( 25 mm +)and use that manually. It takes some effort, but it does work.

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parsj1957
Posts: 60
Joined: Sun Dec 22, 2019 10:22 am
Location: San Francisco Bay Area

Re: Help needed !

Post by parsj1957 »

Also if you like hand tools - a spoke shave works well on both inside and outside curves --
J.

Nigeb22
Posts: 13
Joined: Mon Jul 01, 2019 1:57 am

Re: Help needed !

Post by Nigeb22 »

Thank you everyone I have a belt saner and ordered up a spoke shave as
I see there are lots of curves to shape so I need to get good at this
Anyway thank you its great fun to be building a boat again!

Nigeb22
Posts: 13
Joined: Mon Jul 01, 2019 1:57 am

Re: Help needed again

Post by Nigeb22 »

Hello all
I can see I'm going to be a regular on here to make sense of the plans

I managed to create lot of dust today fairing down the Stem to nice curves and size
and I came to cut out the Breasthook when I got stuck
The plan section seems ok.... 2x 18mm( ¾ ins) marine plywood with a notch to locate into the back of the stem
which allows for a 40mm longitudinal to slot in front and then the stem faired down to a point and flush with the longitudinal

Ok so far so good the confusion arises with the vertical section which indeed seems to show 2 x 18mm ply but one covers the top
of the stem the other slots in underneath and behind but neither seem to do what the plan shows...?

Can anyone tell me what/which drawing is the correct one to follow and explain when its mounted upside down in the frame
does the breasthook fit flush with the lowest part of the stem ( when viewed upside down) and so this is the level the plans demand
as measured from the datum line and then I build up and support the stem at this level?

I hope I've explained this ok
As ever your wisdom is appreciated

Nige
Boycies Barrelback in Portugal
Attachments
IMG_6895.jpeg
IMG_6894.jpeg

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Roberta
Posts: 7198
Joined: Tue Jul 31, 2007 5:23 pm
Location: East Troy, Wisconsin

Re: Help needed !

Post by Roberta »

You make the bottom one notched per the dotted lines and the top one following the outside lines to form the tip that will extend over the stem.

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

Nigeb22
Posts: 13
Joined: Mon Jul 01, 2019 1:57 am

Re: Help needed !

Post by Nigeb22 »

Roberta

Thank you for your prompt reply and info

I think I understand so we have the exact shape of the bottom one which is notched into the stem

Whats the shape of the top one why doesn't the plan explain this ?
I may be feeling my way on this but that is not explained on the plans at all well

I shall pass on my comments to Gayle, are the plans drawn to assume a level of knowledge?

kind regards

Nige

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Roberta
Posts: 7198
Joined: Tue Jul 31, 2007 5:23 pm
Location: East Troy, Wisconsin

Re: Help needed !

Post by Roberta »

The top piece is drawn over the bottom and overhangs the stem. The angled tip is the approximate shape of the leading edge of the stem.

If you don't already have it, get the "Boatbuilding with Plywood" book from Glen L. It will help explain many things about boat building.

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

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DrBryanJ
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Joined: Fri Jul 22, 2011 6:05 am
Location: Pompton Plains, NJ

Re: Help needed !

Post by DrBryanJ »

Both the top and bottom are cut to the same size, only the bottom piece will have the notch. The sides are angled. I know with the Malahini the angle is specified. I don't know if it is with the barrelback. I made my two pieces, attached them together and cut the angle with a table saw. Watch where you put the screws or nails. Too close to the edge and the saw will hit them.
Bryan

Building a malahini "Mona Lisa"

My wife said "If I build a boat, she's getting a divorce."
We're still happily married, but now she just wants "the dam boat out of the garage."

Feex
Posts: 38
Joined: Wed Nov 28, 2018 9:24 am

Re: Help needed !

Post by Feex »

DrBryanJ wrote:
Sun Dec 06, 2020 9:50 am
Both the top and bottom are cut to the same size, only the bottom piece will have the notch. The sides are angled. I know with the Malahini the angle is specified. I don't know if it is with the barrelback. I made my two pieces, attached them together and cut the angle with a table saw. Watch where you put the screws or nails. Too close to the edge and the saw will hit them.
It's actually a very soft curve, not a straight angled cut. Trace the pattern and cut with jig or band saw.

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