hello everybody this is question and
answer number seven and if you haven't seen any of these before it doesn't
matter where you jump in because they're pretty much stand along sets of
questions that people have written in to me and I'm answering the questions as I
go on we've decided to make films of it so that it will reach a much broader
audience and today the first question is from I'm not sure how to pronounce this
I think it's Yanis it's this person is asking is there an optimal height to
press the saw set plunger on saw teeth as in position on the tooth
are there any hazards of it being too low or too high and I wanted to
introduce something that this question I might not have asked or you may not have
asked in that question and that is I just want to point out that not all saw
sets are created equal even though they may be made by the same manufacturer
this is an old one this is a more modern one there might be thirty years between
manufacture and that will make things differently even though it may have been
the original intention of the manufacturer to make them identically
they do vary between each one and I've picked up even modern makers Saw-Max is a
modern maker and I've picked up two made in the same Factory at the same time and
they've come out slightly differently so you do have to bear that in mind I want
to point something out with this question because what the questioner
doesn't realize I don't think is that the saw set itself is suspended on the
saw plate at a fixed at two fixed points so when you slide this onto the sole
like this this outside here and this outside here are on the tops of the
teeth adjacent to one another and there's a span of metal inside here that
is wide enough to make sure that it spans two teeth so you're going to hit a
tooth either side of the tooth you want to set anyway so when you lower it on to
the plate like this it's going on to those two fixed points
can you see that click click so it's suspended on that fixed point so when
you actually press the plunger by squeezing the grip here you squeeze
squeeze the the top is actually going down the bottom is in a fixed position
so that moves a plunger forward inside here that we call a hammer that presses
it against this rotary wheel inside here that we call the anvil so the hammer
hits the anvil and that's what bends the tooth it literally bends it doesn't
really hammer it but it's a good analogy there so when we set this on the tooth
here's what happens generally we position the set so that the plunger
sits right on the very center of the point of the tooth that's where it
should sit so it bends the tooth we lower it onto those two fixed points so
it's at a fixed depth so we really don't adjust it up and down to bend the tooth
we Bend the whole side of the tooth and that's what bends the tooth exactly the
right place but the issue for me I wanted to point out is the inequality
between two saw sets this saw set I don't know if you can see it but right
inside here the top of the plunger itself the hammer actually goes higher
than the anvil that it's pressing the tooth against so it's higher up if I
took another saw set by the same maker and put this one on the same tooth
and I press it this plunger is the same exactly the same height as the anvil
it's pressing against so when it presses the tooth it's actually pressing it
there more of the top edge of the tooth it's pressing much more of the tooth
than this one as this one actually bends it over the top of the anvil so it will
affect the set of the teeth but it doesn't matter because you're using one
saw set on the whole saw in doing both sets both sides of the teeth so
whichever saws that you use it doesn't matter you will experiment with this
rotation on this rotary wheel here because you get less set or more set
according to this angle because it's got an eccentric wheel on there and you
go to a deeper set or a lighter set if you've got it a shallow set you would go
for say a number 12 which is the shallowest set this one does if you want
a big set very heavy set you would go all the way around to the other end of
the wheel and you can see a slight discrepancy here it's actually a
substantial it's probably a millimeter and a half or two mil between the steep
set on the number four and the light set on the number 12 that should explain
everything I'm pretty sure so that's great thank you for the question this
questions from Aaron and he said he has a question regarding pilot holes how big
should a pilot hole how big should a pilot hole be to accommodate the screw
and it does vary with the wood and it varies with the screw type as well and
the reason he's asking the question is we generally have two diameters in the
screw we have the diameter of the threads and then we have the diameter
inside the threads if you can see in there you'll see the main shank inside
the screw so that might be three millimeters whereas the threads
themselves might be five millimeters but what you want to do is retain enough
meat in the wood for the threads of the screw to bite into the wall of a hole so
let me drill a couple of holes and give you an example of what this the
reason we do it one it makes the screw a whole lot easier going into the wood so
if we take a piece of wood like this piece here this is quite a thin stock if
I if I let me do one thing first let me show you what happens if I don't drill a
pilot hole and then show you what happens if I do so if I take a screw and
drive it into the wood here so I'm coming in from the end of this piece of
wood here like this and watch what happens to the
wood can you see that splitting the wood there so it split it on both faces here
it split here and it's split down there if I took a screw and did that along
there then those holes that that split is going to continue all along the edge
but if I put a pilot hole in there that changes the whole thing so can you see
what I've got here I've taken a drill bit the drill bit is the size of the
main body the main shank of the screw inside the threads so the threads are on
either side of the hole so when I drill a hole now I go somewhere near there
about the same this will be very unusual to actually put the screws near to the
end like this or less common we're trying to avoid that sometimes it's
necessary so now when I take a screw and I drive it in here the screw still bites
here but the wood didn't split and I do that with all holes so there's no sign
of any splitting on the wood and that's very important so it took the main body
of the screw the threads are still biting into the wall of the wood or the
wall of the hole and that's why we drill pilot holes if you were doing this in a
hardwood and more dense grain wood like rose wood then I think I would even put
a larger hole than this so that there is less screw thread going into the wall so
I might take an even larger hole like this or a larger drill bit like this one
and make this even bigger than this one that that's where we have to experiment
with the wood first so we try it in different ways so that's what we do in
the reality of everyday we we try things out so that's that answer for you Aaron
thank you for that that was a good question we do that all the time we pre-drill pre
bore lots of times this one's from Joel I'm gluing up some
panels to build a knockdown cabinet I'm using dimensioned white oak I cut it to
rough length then I planed face plane the edges two together of
course then I glued them together then I planed and scraped them to get them almost finished ready then I dimension
the path of the final size and next will come the joinery then we'll come shaping
arches at the bottom of the side panels so he's telling me the sequence of
things that he's done and I can't see anything wrong with what he's done this
then then will come the final scraping and sanding and then the finishing
nothing wrong with what you've done there but then you say this seems like a
reasonable order in which to work any suggestions I'm thinking that I should
have ripped the board's to width before I glue them up and I think that's true
generally we take the width down to where our finished panel after we've
glued up will just be slightly oversized maybe an eighth of an inch quarter of an
inch half an inch and then we'll rip down that last width after we've glued
up and so that would be the preferred way I think you've answered your own
questions throughout there I think you've done that's the reasonable
or the practical way that we demand that we get up materials ready for something
like that project of course it will vary with every different project you may not
be gluing up panels this I'm answering in terms of what the way you phrase the
question so yeah great the other thing though I should add a little note to
myself here we do have a number of stock videos on preparation of materials
and so on so and we are planning on putting out some more because there are
more questions behind the questions that I wanted to answer you know when do you
reverse the board's or at what point do you do this or that so I want to answer
some of that too for sequential cutting where you might want to do book matches
and that kind of thing thank you Joel that was great
this one's from Andy he said that I have some wooden and infill planes they have
the blade bevels ground at 17 to 20 degrees now he's saying this is all this
is something unusual and I understand why he's saying it because we've
kind of reached a legalistic way of grinding the bevel and we grind
everything 25 degrees and nothing else will do
that's not the case at all we'll talk about in a second the math is so tight
on the infill plane that it appears one has to grind to less than 20 degrees for
the iron to seat and extend sufficiently into the mouth is this low angle low
bevel angle something you have come across yes for years for centuries
probably two centuries you will find that most chisel and plane iron were
ground to somewhere anywhere between 15 and 20 degrees
they had these long sweeping bevels on them and it's only in recent generations
in the last 50 60 years where we've become so legalistic that it has to be
grounded 25 degrees that's not the case at all
when they were grinding they just ground it out got it out of the way made no
difference to the plane the functionality of the plane and on these
older planes where the the mouths were tight especially on the panel planes
which were set aside for more refined work they did have them very tight on
the mouth so that was the reason for that so yes you can grind your angles at
2025 degrees that's perfectly okay anywhere from 17 to 25 degrees is
perfectly acceptable you don't have to be legalistic about it
so that's great it's only been in the recent years at that change so Brett's
asking a question here how long do you wait for rough lumber to settle or move
do you dimension the wood to its final size and then set it aside or do you
dimension oversized and let it sit and then re dimension again after the wood
moves I seem to have a problem with mud wood moving after I dimension it
and as I creep closer to the final size it moves again I think this is true
Brett I think this happens a lot of times we don't realize how much wood
will absorb if I take a board of wood like this and put it on my bench leave
it here overnight the atmosphere is charged with moisture the bench between
the wood and the underside of the piece of wood is not absorbing moisture this
side the end grain is of orbing moisture it changes overnight
definitely it does what I might suggest is that when you dimension your wood
know you you keep your wood in stock for as long as you come beforehand that's
what I try to do i'm buying materials my atmosphere that I work in I try to keep
at a fairly constant level and then when I come to work the wood is
fairly stable I can machine it I can hand plane it whatever I want but I try
not to leave it for too long before I get working on the joinery because the
joinery itself does constrain the wood so we take the moisture content down
we've dried it responsibly down to seven between seven and say eleven percent the
atmosphere we're working in is going to be a little bit higher but we start
working with that wood we've reduced as much as we can the possibility of change
but then we start working with the wood we make the joints the joinery itself
constrains what it actually stops wood from changing shape but we don't always
realize that if you compress wood between two surfaces say a frame then
that actually stops it from expanding and it stops it from absorbing moisture
because you know wood is hygroscopic and and it stops it from expanding it won't
stop it from shrinking when it's in the frame so if you have a higher moisture
content it can shrink less than the frame so joinery constrains it turn
buttons on the underside of a table top constrains it we try and work the wood
as close to its milling time as possible so if we're doing jointer we try and do
it within the same day even if we can't do that shrink wrap it put it in a
plastic bag and reduce the amount of moisture that can get back into that
wood by reabsorption which it will do if you've got a rainy day the doors are
open on your workshop we try and constrain that by closing the doors
keeping the heat up a little bit things like that we do as much as we can to
prevent any changes then you seem to advocate sharpening from course through
extra fine on every occasion followed by stropping what are the
benefits of going back through all the stones if you
using an already well-maintained and sharp tool well a well maintained and
sharp tool there is no such thing you can't sharpen a plane and then keep it
in that main maintained condition by just using it you're deteriorating the
cutting edge every time you take a shaving so you're not maintaining it
it's being damaged every time you use it so what you have to do is go back to the
beginning go through the same process because the fastest way to get back to a
cutting edge is to get that bevel down back into the main body of Steel and go
through the same processes it's much faster to do it that way than it is to
go to a final level of braiding because it's all a braiding and and and to
try to get back to a cutting edge again much quicker to go all the way back to
the beginning every time never fails okay Raul while
cutting a dovetail when I chisel out the middle pieces there is tear out on the
end grain it leaves a small cavity why does it happen and how do I avoid it
several reasons for this it could be I assume that you're not using the coping
saw to cut out the main body of waste I'm assuming that you are using my main
method although I do use a coping saw sometimes but mostly I don't and I use a
chisel you chop down and then you chisel in chop down chisel in and when you do
that sometimes your chisel is getting duller and duller by each blow so you
start to compress the fibers and you put unnecessary pressure on the end grain
then it starts to tear out you're working from both sides there's more resistance as you get nearer to the center it's getting
steeper and it tends to rip out like a tooth out of a socket in a gun and and
that's what happens with the wood so sharp chisel keep sharpening up sharpen
up two or three times during your dovetail depends on the nature of the
wood too soft woods tend to tear out that way some hardwoods will but mostly
the hardwoods will give you a better finish that's great thank you for that
one Raul question from S.
M. Clark what are your thoughts on skew
plays I haven't found any mention of them in your incredible book I didn't
put that bit in or in any of your YouTube videos the answer I've given is
I assume that you're talking about bench planes for surface planning not rebate
planes rebate planes were skewed because the skewing of the blade when it's
pushed into the corner of a rebate it pulls itself to task and pulls itself to
that inside corner on smoothing planes there are not very many smoothing planes
that have skew blades in them very very rare indeed so we tend not to raise the
issue because they weren't common they weren't really used at all so thanks for
all your questions again and these are really helping a lot of people we'll
keep answering them as long as you keep asking questions and always remember
that the hardest question to answer is the one that's never asked you.