Adjusting plane mouth

[Peter Scoma]

Ok, so I started using handplanes just a short while ago and have amassed 1/2 dozen or so that seem to be rather well tuned. From what I have read, users suggest an wide open mouth for removing large material and closing the mouth more for final smoothing, etc.. I may be a little dense but I dont understand how the amount the mouth is opened has anything to do with the thickness of the shavings produced. If the blade is protruding more, you get a thicker shaving, less protrusion, thinner shaving; How is this thickness of the shaving effected by anything other than the depth of the blade?

Are you guys routinely adjusting your frog to vary the mouth opening???

PS

[David Gendron]

you are right about shaving tickness! and also you don't generaly play a lot with the frog on your plane unless you use the same plane for more than one task, like using a #5 for removing stock and to smooth! So let say that you have a dedicated smoother, you would set the mouth fairly tight and set the ship braker also fairly close to the iron's edge(1/32, 1/64) and set the blade for a thin shaving. So the mouth opening have to do with tear out( if I'm wrong, someone will corect me) so closed mouth reduce the tear out by not leaving space to the wood fiber to lift from the boar before it get cut(sorry, anglish as a second language!!) so they don't tear out. Is that make sence?

[Peter Scoma]

you are right about shaving tickness! and also you don't generaly play a lot with the frog on your plane unless you use the same plane for more than one task, like using a #5 for removing stock and to smooth! So let say that you have a dedicated smoother, you would set the mouth fairly tight and set the ship braker also fairly close to the iron's edge(1/32, 1/64) and set the blade for a thin shaving. So the mouth opening have to do with tear out( if I'm wrong, someone will corect me) so closed mouth reduce the tear out by not leaving space to the wood fiber to lift from the boar before it get cut(sorry, anglish as a second language!!) so they don't tear out. Is that make sence?

Ahh. I see what you mean David. Kind of like how a zero clearance TS insert reduces tearout.

My spanish and Italian are far worse than your english so don't worry about it!

Thanks
PS

[David Gendron]

Thank you... The zero clearance insert would be a good comparison! Let see what people say tomorow!!
David

[jim carter]

you are right about shaving tickness! and also you don't generaly play a lot with the frog on your plane unless you use the same plane for more than one task, like using a #5 for removing stock and to smooth! So let say that you have a dedicated smoother, you would set the mouth fairly tight and set the ship braker also fairly close to the iron's edge(1/32, 1/64) and set the blade for a thin shaving. So the mouth opening have to do with tear out( if I'm wrong, someone will corect me) so closed mouth reduce the tear out by not leaving space to the wood fiber to lift from the boar before it get cut(sorry, anglish as a second language!!) so they don't tear out. Is that make sence?

nicely said. i went to school for cabinet making and the first test i got was a plane test. they gave me a block of wood that had no square sides and i had to square it with a hand plane. it had to pass a square test on all sides and there couldnt be any daylight as the square was run across every side. easier said than done. took me a couple times, so i respect someone that knows how to use a hand plane

[David Gendron]

Thank you, I just started about 10 months ago to do real wood working and since I do every thing with hand toos I had to learn fast I guess... I find out that a lot of it is comon sens! Of course now a day with the internet, you can find so much info so fast that it make the learning go faster... that said, I preffer books and magazins!
Have a good one!
David

[Brian Kent]

I agree - what David said.

[Jim Koepke]

My planes do not have their frogs adjusted very often. For the planes that would be most likely to have the frogs adjusted, extras have been acquired. So there are two #5 and #4 planes with the mouths set tight on one each and the others are set with a wider mouth.

Of course, this does not explain how there are now two #6s in the shop or a lot of other things, but I'm sticking to the story.

The mouths on my planes tend to be set more to the tight side. My recently acquired #8's mouth needed adjusting because it would get stuck shavings on thicker cuts. I guess you could say it had a little frog in its throat.

jim

[David Gendron]

Jim, how close do you set the chip braker on you different plane irons? The reason for your #8 to clog up, would it have anything to do with the chip braker to be to close to the edge of the iron?

[Jim Koepke]

Jim, how close do you set the chip braker on you different plane irons? The reason for your #8 to clog up, would it have anything to do with the chip braker to be to close to the edge of the iron?

The chip breaker is usually at about 1/32". In this case, the mouth was set by eye with the original blade. A Hock blade was ordered. When it arrived, it was installed. For real fine shavings this was fine. With a thicker cut, any tear out would clog the throat. So, the frog was moved back a hair to compensate for the thicker blade.

Most of the time my shavings tend toward the thin side. Seldom anything over 0.005", then only for a few passes on rough stock.

jim

[John Keeton]

Of course, this does not explain how there are now two #6s in the shop or a lot of other things.....Leave the lights on Jim. They only reproduce in the dark!

[Danny Burns]

If you are working in regular grain wood, then a wide mouth opening for all thickness of shavings is alright.

When you get into wild grained wood, then you need the plane to apply pressure on the wood, just before the cutter, in order to try and keep the wood from cracking ahead of the cut.
Here a tight mouth is needed, along with thin shavings, since they are weaker, and so they curl up, which breaks the chip, and reduces the splitting ahead of the cut.

This is the only time a tight mouth will help you, so a fairly open mouth in regular grain will allow you to take both thin and thick shavings with the same plane, where if you had a tight mouth, then you would have to adjust the opening, since the plane would choke on the shavings.

Here are some links about type I and type II shavings.

http://planetuning.infillplane.com/html/shaving_formation.html

http://www.leevalley.com/shopping/Instructions.aspx?p=55949

[Doug Shepard]

Do some of you actually vary the distance of the chipbreaker to the erdge depending on shaving thickness? That's the first I've heard of doing that.

[Jeff Willard]

I guess you could say it had a little frog in its throat.


That's bad.:eek: There should be some form of penalty for that one.

[David Gendron]

Doug, I do set the chipbreaker differently for different plane. I know if I set the chipbreaker to close to the edge fof the iron on a plane with a closed mouth, it will clog up more esealy and if I set it(chipbreaker) to far on a plane that the mouth is wide open I have more chances of chatering. Is that make sence? I hoppe I'm kind of right!
David