Planing a board flat - Is there literally no light when testing with a straight edge?

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David Charlesworths videos are totally comprehensive.
The problem is that he is so thorough precise and somewhat pedantic that a process that only takes a relatively short time seems complex because of how long he takes to explain every every minute detail
As a beginner I would agree with taking a more basic approach .
Yes keep it simple and save the gurus for later. You'll find you don't need them!
Difficult to know who is worth following so you have to be very sceptical, especially if they are trying to sell you stuff.
 
...

Take a piece of 1/2" thick plywood and screw it to your bench. Quick and easy.
I sometimes clamp a board flat on the end of the bench, as a stop. If it's wide enough the clamps don't get in the way of planing and you don't have to screw into the bench top, though I do that often as well.
 
Hey all,

I'm a newbie and I'm sure like many, struggle with flattening stock. I've rewatched a few of the classic recommendations on YouTube a few times.. but I always find myself bewildered when I go to put it into action.

When you hold a steel ruler to a piece across the width, if it's truly flat is there actually no light, even when holding up to a LED roof batten etc?

I know it takes time lol.. but it's proving difficult to get the boards even close to being "lights out".

My method currently roughly entails the following:

1.) Pick a side to work on
2.) If convex in middle, scrub plane across the board to remove a lot of high spots.
3.) Quick check, then look for twist
4.) Try diagonal plane high spots from each end
5.) Check again, repeat as required.
6.) Try finish with No4/5 up and down, targeting areas that look high when glancing ruler at light

I feel like my boards are just getting thinner and thinner as it's a never ending cycle lol especially when I get to point 6 above..

Any tips greatly appreciated! I've watched Paul Seller's, Rex Kruger, Matt Estlea, Chris Schwartz and probably more in attempts to get me head around it lol..

I'll try post an example picture of my latest board to get some clarity a bit later

Cheers
When planing an edge one of the best ways to quickly tell if it’s flat or thereabouts is the sound the straightedge makes when you place it on the wood.
Flat always sounds different and is a single crack, very distinctive and different to when it’s not flat.
 
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When planing an edge one of the best ways to quickly tell if it’s flat or thereabouts is the sounds the straightedge makes when you place it on the wood.
Flat always sounds different and is a single crack, very distinctive and different to when it’s not flat.
I’ve always found it interesting how useful your ears are in woodworking, there are a number of things you can tell by the sound of things. I’ve not experienced this one so will have to listen out for it.
 
Only if you have sharp ears.
Do you have to flatten them on one side before you sharpen them?

The whole business of flattening boards needs to be kept in context.A perfectly flat board may have moved a bit by the next day and be slightly different.Which may then get better-or worse.You can minimise this by seeking out quarter sawn boards and there might be a premium to pay for getting them.
 
And, of course, there is no such thing as perfectly flat in practice. A board is just a collection of wave functions or something...a superposition of flat and not flat, that collapses into one or the other when you get the ruler out.
 
I used to spend hours planing a perfectly flat edge for joining boards. Then I realized that a good blade in the tablesaw achieves the same results in minutes. I stick to Freud blades and make sure they are absolutely at 90 degrees to the tablesaw bed with a digital inclinometer. I have a DeWalt 746 saw ( sadly no longer available ) with a separate trunnion so that's a help. Not a purist approach for woodworking but it works for me. ;)
 
Listening to the sound wood makes when knocked is ( I have found ) a very good guide as to how dry it is. Knocking on it with a tuning fork and then placing the base of the tuning fork on the end of the log will tell you a great deal about the grain of the log.

So, Spock was an ace woodworker eh ? as would be Gnomes, elves etc. Galadriel, dab hand with a plane.
 
I used to spend hours planing a perfectly flat edge for joining boards. Then I realized that a good blade in the tablesaw achieves the same results in minutes. I stick to Freud blades and make sure they are absolutely at 90 degrees to the tablesaw bed with a digital inclinometer. I have a DeWalt 746 saw ( sadly no longer available ) with a separate trunnion so that's a help. Not a purist approach for woodworking but it works for me. ;)
Whatever works for "you"..is always "the best way" :) .
 
As another relative novice, I remember quickly learning that I was setting my plane iron too heavy, and how the adjustment wheel only needs to be turned a fraction to make a difference. Heavy shavings obviously won't flatten a piece well towards the end of the process, so lightening up can really take all those discrepancies under the straight edge out.
 
The wavelength of visible light is considerably smaller than any gap you are likely to achieve via hand planing, so if the angle is right you’ll definitely be able to see a glint.

Unless your straight edge is an engineering one it’s unlikely to be very straight anyway.

The best way to test is with feeler gauges, trying to poke them under the straight edge. A typical set goes to 1.5 thou and this is fine for any woodworking purposes including checking plane soles. With feeler gauges you can get an actual measurement.

As someone mentioned above, what is flat anyway? Any surface, other than possibly a crystal, is a bunch of high and low points. Flat is where the high points all fall within a tolerable range, and are evenly distributed across the surface. If you ever get into scraping cast iron machine tool surfaces flat (not recommended), you learn a lot about this topic.

For woodworking, nothing is really remotely flat or stays flat. If it looks flat enough, and can mate with a surface it needs to mate with, it probably is.
 
Unless your straight edge is an engineering one it’s unlikely to be very straight anyway.
Nothing is absolutely straight. The closer you look the more errors you'll find. Any error less than say 0.5mm is perfection as far as woodworkers are concerned
........ With feeler gauges you can get an actual measurement.....
That way madness lies. o_O Woodworkers really do not need feeler gauges.
 
Why start off with bad habits in the first place? i.e...like
Planing panels in vice, or long edge planing with only a vice.
Planing panels squeezed between dogs.
Unsupported thinner work without acknowledgment regarding the opposite face.

Wiping out the edges planing cross grain making the work narrower or thinner for no reason if coming at it from the far side, or chasing the grain around knots or whatever, not using a method which can ensure planing in rows/with the grain.
(That's not to suggest one cannot plane corner to corner, but the fact one doesn't have to tango,
and can simply use a single planing stop.)


Encouraging ignorance with no lamp, which if used correctly can be very very useful,
especially good for spotting who's telling the truth, and who isn't.
Not having a proper surface to work on, and the care of the surface thereafter.

Try finding anyone who doesn't have those bad habits, and likely you won't find it,
not from any teacher guru anyway.
This would become very apparent after watching a Charlesworth video.
His lessons were written in such a way as to make one aware of all that,
and should one wish....
they can take home a lot more stuff than anyone else's efforts.
All in all, honest lessons for refined work, with techniques which one will use forever,
and are not pretending.

All the best
Tom
 
Why start off with bad habits in the first place? i.e...like
Planing panels in vice, or long edge planing with only a vice.
Planing panels squeezed between dogs.
Unsupported thinner work without acknowledgment regarding the opposite face.
Does " acknowledgment regarding the opposite face" mean the same as "putting your workpiece on a flattish work surface" and does anybody really need to be told this in the first place? :rolleyes:
Wiping out the edges planing cross grain making the work narrower or thinner for no reason if coming at it from the far side, or chasing the grain around knots or whatever, not using a method which can ensure planing in rows/with the grain.
(That's not to suggest one cannot plane corner to corner, but the fact one doesn't have to tango,
and can simply use a single planing stop.)


Encouraging ignorance with no lamp, which if used correctly can be very very useful,
especially good for spotting who's telling the truth, and who isn't.
Not having a proper surface to work on, and the care of the surface thereafter.

Try finding anyone who doesn't have those bad habits, and likely you won't find it,
not from any teacher guru anyway.
This would become very apparent after watching a Charlesworth video.
His lessons were written in such a way as to make one aware of all that,
and should one wish....
they can take home a lot more stuff than anyone else's efforts.
All in all, honest lessons for refined work, with techniques which one will use forever,
and are not pretending.

All the best
Tom
Tom is still under the influence! o_O
 
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Does " acknowledgment regarding the opposite face" mean the same as "putting your workpiece on a flattish work surface" and does anybody really need to be told this in the first place?
It means thin stock will bend if the underside isn't flat.
You might not have noticed as you said yourself, you work to no better than 1/32".
 
Nothing is absolutely straight. The closer you look the more errors you'll find. Any error less than say 0.5mm is perfection as far as woodworkers are concerned

That way madness lies. o_O Woodworkers really do not need feeler gauges.

For general woodworking I totally agree, which is what my post said but for some types E.g. luthiery, you are making a precision device and so they are necessary.

Also, flattening plane soles is (often) metalwork, not woodwork and they are extremely useful for that. I’d definitely recommend them over the “light test”. 2 thou will give you plenty of light but is fine for plane sole flatness.

I use them all the time for testing the fit of a wedge in a moulding plane or the bedding of an iron.

They are also invaluable for testing the flatness of planes with concave soles, such as hollow or ovolo planes.

But for making a table or chair they are of no use whatsoever.
 

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