Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?

Thanks

"Brian" wrote in message
...
Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?

Pre-saw with an electrical jig saw, outside the lines. Nail a batten down on
the lines and use a router with trimming bit, rolling along the batten.
Makes a Perfect cut.

You can also tack the batten down first and slide the jigsaw aloing it, with
a block screwed under the sole in such a position that the blade cuts about
1/8 to 1/4" from the batten.
See my website at
http://www.customware.nl/boats/en/index.html, look in the diary at February
19 for pictures.


Meindert

Nice boat you are building! One day I would like to try something so
elegant.

The idea with the router is so obvious. I have used the same idea for
straight edges with ply in the past and got great results. I don't know
why I didn't think of using a batten and doing curves the same way. I
also like the jigsaw jig idea.

Thanks for this tips.

Meindert Sprang wrote:
"Brian" wrote in message
...

Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?


Pre-saw with an electrical jig saw, outside the lines. Nail a batten down on
the lines and use a router with trimming bit, rolling along the batten.
Makes a Perfect cut.

You can also tack the batten down first and slide the jigsaw aloing it, with
a block screwed under the sole in such a position that the blade cuts about
1/8 to 1/4" from the batten.
See my website at
http://www.customware.nl/boats/en/index.html, look in the diary at February
19 for pictures.


Meindert

"Brian" wrote in message
...
Nice boat you are building! One day I would like to try something so
elegant.

Thanks. Well, it wasn't too difficult. After all, it was our first boat we
built.
I need to update the site, she's already sailing for two years... :-)

The idea with the router is so obvious. I have used the same idea for
straight edges with ply in the past and got great results. I don't know
why I didn't think of using a batten and doing curves the same way. I
also like the jigsaw jig idea.

The jigsaw jig made the job very easy. Once setup, it's just a matter of
tacking the batten in the right shape, run the jigsaw, run the router and 10
minutes later you have perfectly cut strake which looks like it's been
laser-cur. But indeed, the obvious solutions often aren't so obvious.. :-)

Thanks for this tips.

My pleasure!

Meindert

I cut gentle curves by hand with a pullsaw.... cuts faster and smoother than
a jigsaw.... but not round *tight* curves.

"Brian" wrote in message
...
Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there any
other methods that can produce good results?

Thanks

I had not heard of a pullsaw but have read up on them and they sound
worth looking into. The idea of a narrower cut due to narrower blade
makes a lot of sense.

I will keep my eyes open for one in the shops.

Thanks for the info.


James wrote:

I cut gentle curves by hand with a pullsaw.... cuts faster and smoother than
a jigsaw.... but not round *tight* curves.

"Brian" wrote in message
...

Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there any
other methods that can produce good results?

Thanks

On Wed, 20 Apr 2005 23:08:28 +1200, Brian
wrote:

Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?

Thanks

A power jig-saw does good work, if equipped with the right blade. A
fine metal blade might be better for thin sheets, which otherwise show
one ragged edge unless backed.

Brian Whatcott Altus, OK

Today I have bought some fancy blades which I am told should do a better
job than the standard blades that came with the jigsaw.

They are bosch "clean for wood" - "clean cut" blades with 1.4mm pitch
teeth. I will post an opinion when I try them out.

Thanks for the reply

Brian Whatcott wrote:

On Wed, 20 Apr 2005 23:08:28 +1200, Brian
wrote:


Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?

Thanks


A power jig-saw does good work, if equipped with the right blade. A
fine metal blade might be better for thin sheets, which otherwise show
one ragged edge unless backed.

Brian Whatcott Altus, OK

Depends on what kind of saw you happen to have.

An electic circular saw can follow a curved line because the blade only
has to be set very shallow. Use a thin kerf blade with lots of teeth. I've
used a blade with 40 teeth. They make a special plywood blade with many
more teeth but I haven't found it to be any better. The only problem with
a circular saw is they tend to be heavy so the plywood should be well
supported and you have to go slow. I've found the thin blade of a jig saw
(sabre saw) can wander off the line pretty easy to you have to be careful.
You can also try sawing through masking tape to reduce tearing along the
edge. The jig saw and circular saw blades cut on the upstroke so the tape
has to be on the top side.

Brian ) writes:
Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?

Thanks


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You are right about the weight of the circular saw. I don't think the
beast I have would work very well. Using masking tape is an interesting
idea but it would of course require that the lines be drawn on the tape.

I have been looking at circular saw blades but have not found anything
specially of ply. I will look for something thin with lots of teeth though.

Thanks

William R. Watt wrote:

Depends on what kind of saw you happen to have.

An electic circular saw can follow a curved line because the blade only
has to be set very shallow. Use a thin kerf blade with lots of teeth. I've
used a blade with 40 teeth. They make a special plywood blade with many
more teeth but I haven't found it to be any better. The only problem with
a circular saw is they tend to be heavy so the plywood should be well
supported and you have to go slow. I've found the thin blade of a jig saw
(sabre saw) can wander off the line pretty easy to you have to be careful.
You can also try sawing through masking tape to reduce tearing along the
edge. The jig saw and circular saw blades cut on the upstroke so the tape
has to be on the top side.

Brian ) writes:

Does anyone have any tips on the best ways to cut marine ply (6, 9 and
12mm)? In particular I want to cut curved 8' boards for a dinghy. So I
guessing that a band saw is a good bet but I don't have one. Are there
any other methods that can produce good results?

Thanks



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homepage: www.ncf.ca/~ag384/top.htm
warning: non-FreeNet email must have "notspam" in subject or it's returned