PRIVATE: 1/4 " Plywood lapstrake with 3/4 "Spacer"
Pat,
Last week, I followed the thread pretty closely because I am interested in
epoxy fastened ply lapstrake. I thought there were two posts that explained
the process quite well. As I understand, your problem is "seeing" the gains.
I'm sorry that I can't look at your drawing. Yahoo/eGroups is like a cow.
Each time they blink their eyes, it is a new day. From one day to the next no
one knows how to sign on. If you can move your file over to Yahoo bolger
groups, there is a better than even chance that I can view it on any given
day.
Anyway, the method of making the lap gains is very clear to me. If there is
any way I can help you visualize it, it will cost you only a good ale if I
ever get up your way :-)
I'm going to start with a "fable" which contains an incorrect concept. I'll
correct that later, but just stick with the explanation and don't look for
the error. If you spot it, ignore it for now.
Imagine, if you will, that there is already one plank on the forms, placed
there by the "old boat builder fairies", and you are getting ready to put on
the next higher plank. Pretend for a moment that the plank in place is 1"
thick and the one you are getting ready to put on is 1/4" thick. First,
you'll want to determine how far the taper of your gains need to extend.
Let's say they will be 36" long (they wouldn't have to be for 1/4" but they
would have to be that long if all planks were 1" thick).
So, imagine that you take your plane and, starting 3' back from the end of
the plank (bearding line) you taper the top part of the 1" thick board so
that it is 1/8" thick where it lands in the rabbet. Let's say that this
tapered part is 1" wide also, which is reasonable. Do the same to the other
end. You now have a plank on the forms that is 1" thick in the middle and
everywhere else except for a strip 1" wide over the last 3' at each end.
There you have a regular and smooth taper from 1" thick to 1/8" thick *on the
upper 1" of the board only. It is like a little ramp at either end.
Now, grab your next plank, which is 1/4" thick, and on the bottom of this
one, make matching gains that are 1" wide and taper from full thickness at 3'
from each end to 1/8" at the ends. If you flip that board over and offer it
up to the one the fairies did, you will find that those gains match and the
new plank fits onto the fairie plank exactly as if each plank were only 1/4"
thick.
Now, here's the fable part. The fairies really would have cut those two gains
on the 1" thick plank before they glued it on, and so will you. Each plank
(except for the garboard, will have 4 gains on it before you fasten it. The
two gains on the bottom will be on the inner surface and the two at the top
will be on the outer surface outer surface.
Next fable part. Your bottom board isn't really 1" thick, it is 1/4" thick
and it has a 3/4" spacer on it. That spacer can't be glued to the bottom
board before the board is hung or you'll have a hell of a time getting it to
go on. But, if you lay it flat on the bench and cut both gains, then when you
hang the plank, the curvature will make the spacer too short by a fraction of
an inch. DAMN!!! Why didn't I just do this the standard way??????
Here's the way out of that...matter of fact, there are two, but we'll do only
one. Don't even think of glueing the spacer to the upper plank's bottom edge
before you bend it. You *won't* bend it in place :-), you'll break it. Back
to the method (aren't you glad I spent 15 years as a technical writer???).
Clamp the plank to the bench with the spacer lying in the correct place, just
make the spacer 1/4" longer than the plank. Now, on the end which has the two
pieces even, cut the gain. Now, move the spacer so that the other ends are
even. Cut a gain. Offer the plank up to the form and clamp it. Now lay the
spacer over the plank in the correct place. You'll find that it is just a
hair too long (but not the full 1/4"... only fairies can make *that* happen
:-) So, measure how much too long it is and remove it from the form. Go to
the bench and cut off the "too-longage" from the end. Now, adjust the gain
with your plane. you will have to plane off a constant thickness now instead
of a tapering bit as when you first did the gains.
Now, take that sucker back to the form and glue it in place. It will fit
perfectly. Now when you hang the next plank, the gains that you made to fit
the fairie plank wil fit perfectly. BUT!!!! don't forget to cut the gains on
the spacer for that plank before you hang *it*.
Here is the sequence. (Garboard uses modified sequence, but I'm sure you see
that now)
cut the lower gains in the inner face of a 1/4" plank
turn the plank over and clamp a too-long space to the top outer surface and
cut the fiddly gains in both the plank and the spacer
hang the plank
hang the spacer
Repeat until done...don't cut gains in the upper outer edge of the top
plank...wati until it's hung and use your plane to match it up to the
stem/stern post/transom, etc.
Now about that plane. DON'T attempt this with a standard smoothing or block
plane. You'll need a rabbet, a filister, or a skew plane. As a matter of
fact, you'll also need a bullnose to do the cleanup at the ends after the
glue has dried, but you *can* get by without it by using a good sharp bench
chisel AND KEEPING IT SHARP!!!.
Best and cheapest will be to buy a wooden skew plane that is exactly the
width you want the gains to be (we pretended 1" above, and that is good
because all these planes come in that width. If you need something else,
don't worry, you can probably find that too in old wooden planes). You can
get a metal bodied bullnose plane form Record or Stanley for a reasonable
sum. As a matter of fact, you can get a rabbet plane with a removable nose
which will do both the body of the gain and the cleanup. However, changing
back and forth is such a pain in the coccyx that you'll wish you'd bought a
proper plane for each job.
Next part: your job will go much easier if you'll make a jig to put the plank
and spacer on. This is just a board with "continuations" of the gain at each
end, on the edge near the front of the bench. These allow the plane to easily
continue the taper off the end of the plank. These two jig gains will ideally
be farther apart than the length of your longest board. When you unclamp
after doing the first gain, you'll scoot the plank and spacer down a bit then
re-even the ends and reclamp to so the second end.
Now, to get the best deals on these planes, contact a galoot named Trevor
Robinson and tell him that you need (read the above description). If you
aren't really good at sharpening tools, and don't want to learn, I've wasted
a bunch of my time. Get another hobby that isn't so demanding of skills.
Here's Trevor (no connection except that he gets too much of my money :-)
DAng!! I've lost Trevor's email address!!!
Search for "The Front Porch". It's a site dedicated to wierdos who love old
tools. Sign onto the OldTools mailing list. Send out an appeal for Trevor.
You'll find lots of folks selling this stuff, most of whom are trustworthy.
Most of eBay isn't.
Let me know, if you can, what isn't clear.
Cheers/Carron
decided to send it to the list in case there is another crazy about.
"LABOR SVGIT"
Last week, I followed the thread pretty closely because I am interested in
epoxy fastened ply lapstrake. I thought there were two posts that explained
the process quite well. As I understand, your problem is "seeing" the gains.
I'm sorry that I can't look at your drawing. Yahoo/eGroups is like a cow.
Each time they blink their eyes, it is a new day. From one day to the next no
one knows how to sign on. If you can move your file over to Yahoo bolger
groups, there is a better than even chance that I can view it on any given
day.
Anyway, the method of making the lap gains is very clear to me. If there is
any way I can help you visualize it, it will cost you only a good ale if I
ever get up your way :-)
I'm going to start with a "fable" which contains an incorrect concept. I'll
correct that later, but just stick with the explanation and don't look for
the error. If you spot it, ignore it for now.
Imagine, if you will, that there is already one plank on the forms, placed
there by the "old boat builder fairies", and you are getting ready to put on
the next higher plank. Pretend for a moment that the plank in place is 1"
thick and the one you are getting ready to put on is 1/4" thick. First,
you'll want to determine how far the taper of your gains need to extend.
Let's say they will be 36" long (they wouldn't have to be for 1/4" but they
would have to be that long if all planks were 1" thick).
So, imagine that you take your plane and, starting 3' back from the end of
the plank (bearding line) you taper the top part of the 1" thick board so
that it is 1/8" thick where it lands in the rabbet. Let's say that this
tapered part is 1" wide also, which is reasonable. Do the same to the other
end. You now have a plank on the forms that is 1" thick in the middle and
everywhere else except for a strip 1" wide over the last 3' at each end.
There you have a regular and smooth taper from 1" thick to 1/8" thick *on the
upper 1" of the board only. It is like a little ramp at either end.
Now, grab your next plank, which is 1/4" thick, and on the bottom of this
one, make matching gains that are 1" wide and taper from full thickness at 3'
from each end to 1/8" at the ends. If you flip that board over and offer it
up to the one the fairies did, you will find that those gains match and the
new plank fits onto the fairie plank exactly as if each plank were only 1/4"
thick.
Now, here's the fable part. The fairies really would have cut those two gains
on the 1" thick plank before they glued it on, and so will you. Each plank
(except for the garboard, will have 4 gains on it before you fasten it. The
two gains on the bottom will be on the inner surface and the two at the top
will be on the outer surface outer surface.
Next fable part. Your bottom board isn't really 1" thick, it is 1/4" thick
and it has a 3/4" spacer on it. That spacer can't be glued to the bottom
board before the board is hung or you'll have a hell of a time getting it to
go on. But, if you lay it flat on the bench and cut both gains, then when you
hang the plank, the curvature will make the spacer too short by a fraction of
an inch. DAMN!!! Why didn't I just do this the standard way??????
Here's the way out of that...matter of fact, there are two, but we'll do only
one. Don't even think of glueing the spacer to the upper plank's bottom edge
before you bend it. You *won't* bend it in place :-), you'll break it. Back
to the method (aren't you glad I spent 15 years as a technical writer???).
Clamp the plank to the bench with the spacer lying in the correct place, just
make the spacer 1/4" longer than the plank. Now, on the end which has the two
pieces even, cut the gain. Now, move the spacer so that the other ends are
even. Cut a gain. Offer the plank up to the form and clamp it. Now lay the
spacer over the plank in the correct place. You'll find that it is just a
hair too long (but not the full 1/4"... only fairies can make *that* happen
:-) So, measure how much too long it is and remove it from the form. Go to
the bench and cut off the "too-longage" from the end. Now, adjust the gain
with your plane. you will have to plane off a constant thickness now instead
of a tapering bit as when you first did the gains.
Now, take that sucker back to the form and glue it in place. It will fit
perfectly. Now when you hang the next plank, the gains that you made to fit
the fairie plank wil fit perfectly. BUT!!!! don't forget to cut the gains on
the spacer for that plank before you hang *it*.
Here is the sequence. (Garboard uses modified sequence, but I'm sure you see
that now)
cut the lower gains in the inner face of a 1/4" plank
turn the plank over and clamp a too-long space to the top outer surface and
cut the fiddly gains in both the plank and the spacer
hang the plank
hang the spacer
Repeat until done...don't cut gains in the upper outer edge of the top
plank...wati until it's hung and use your plane to match it up to the
stem/stern post/transom, etc.
Now about that plane. DON'T attempt this with a standard smoothing or block
plane. You'll need a rabbet, a filister, or a skew plane. As a matter of
fact, you'll also need a bullnose to do the cleanup at the ends after the
glue has dried, but you *can* get by without it by using a good sharp bench
chisel AND KEEPING IT SHARP!!!.
Best and cheapest will be to buy a wooden skew plane that is exactly the
width you want the gains to be (we pretended 1" above, and that is good
because all these planes come in that width. If you need something else,
don't worry, you can probably find that too in old wooden planes). You can
get a metal bodied bullnose plane form Record or Stanley for a reasonable
sum. As a matter of fact, you can get a rabbet plane with a removable nose
which will do both the body of the gain and the cleanup. However, changing
back and forth is such a pain in the coccyx that you'll wish you'd bought a
proper plane for each job.
Next part: your job will go much easier if you'll make a jig to put the plank
and spacer on. This is just a board with "continuations" of the gain at each
end, on the edge near the front of the bench. These allow the plane to easily
continue the taper off the end of the plank. These two jig gains will ideally
be farther apart than the length of your longest board. When you unclamp
after doing the first gain, you'll scoot the plank and spacer down a bit then
re-even the ends and reclamp to so the second end.
Now, to get the best deals on these planes, contact a galoot named Trevor
Robinson and tell him that you need (read the above description). If you
aren't really good at sharpening tools, and don't want to learn, I've wasted
a bunch of my time. Get another hobby that isn't so demanding of skills.
Here's Trevor (no connection except that he gets too much of my money :-)
DAng!! I've lost Trevor's email address!!!
Search for "The Front Porch". It's a site dedicated to wierdos who love old
tools. Sign onto the OldTools mailing list. Send out an appeal for Trevor.
You'll find lots of folks selling this stuff, most of whom are trustworthy.
Most of eBay isn't.
Let me know, if you can, what isn't clear.
Cheers/Carron
decided to send it to the list in case there is another crazy about.
"LABOR SVGIT"