Moulding plane chatter

[Mark Elliott]

I cannot seem to get rid of chatter in my 18th century gunstocking plane.  It is sharp and creates a nice thin ribbon of shavings throughout most of the barrel channel, but I have a bad chatter through the waist that reduces the cutting effectiveness.  This is basically just a moulding plane.  There is a plain iron and a wedge, no chip breaker.   I have tried different sharpening approaches and nothing seems to work.  It is a 3/4" round nose iron with only about 2 inches of the blade remaining.   I currently have it sharpened at about 25 degrees with a microbevel of a couple of degrees.   Should I be using a great bevel angle to back the blade better?  If you think I need a new, longer, blade; I can certainly forge a new one. 

[smart dog]

Hi Mark,
I use molding planes as well and have experienced sections of wood that caused the planes to chatter.  I resolved most problems.  Correct sharpening was one solution and your method is almost exactly what I adopted with respect to angles. I like low-angle planes.   I also prevent chatter by making sure the stock blank is secured so that it cannot flex while I am planing.  I anchor my stock blanks using my leg vises with the side of the blank tucked up against the edge of my bench and further secured with holdfasts.  That set up is rigid. It is also  only 34" high, which allows me to get over the stock and place a lot of pressure downward on the plane with the weight of my body rather than arm strength alone.  That took care of 99% of chatter problems.  However, on the Reading gun I just posted, there was one spot in the barrel channel that tore, chipped, and chattered regardless of what I did.  I solved that by carving out the area with chisels and scrapers to the final depth and then used the plane for the rest of the channel.  My plane simply glided over the problem section until the rest of the channel was down to the finished depth.  One other possible solution for you is a high-angle blade (70 degrees or more) that is more like a scraping plane.  That will strongly support the edge and may solve chatter by scraping off small shavings.  However, most of my chatter problems came from the stock flexing as I planed.

dave   

[Dale Campbell]

Smart dog has probably got you covered. How wide is the throat of your plane? If too wide it can allow the blade to flex in that area of the wood, causing chatter.

[Acer Saccharum]

That is one Smart Dog!

[Acer Saccharum]

I have modified a cheapo iron plane to work like a dream. If sharpened and used like you think it should be, it won't work on curl maple without tearing.

By grinding the blade vertical to the work, it changed from a slicing action to a scraping plane. Now the plane works on curly maple, I can plane against the grain without tear out.



I didn't make this up, I learned it off a friend.

[David R. Pennington]

Looks like these guys have you covered. I have a variety of old molding planes I use for different things. One other thing I might stress is to see if someone has opened the throat up on your plane. I find a lot of old planes ruined this way. Some one who doesn't understand how they work chisels open the throat thinking it will stop the chips from clogging but actually makes things worse. Think about how this works, the body of the plane ahead of the cutter controls how much the shaving can split away from the stock. A wide throat lets too much of the chip tear up. Also make sure the wedge fits tight and exerts pressure all across the iron. You might need to resurface the wedge or make a new one. Some of this curly stuff is so contrary nothing would help. If the throat is too wide you might glue a wedge in and recut the throat. I haven't tried it. When I find them for sale with this problem I just lay them back down.

[Acer Saccharum]

Some of the better iron planes have an adjustable throat opening.

[okieboy]

 Thicker plane irons also help with chatter if there is room in your plane.

[JBJ]

One other point. Make sure the plane iron is resting evenly in the bed. If the bed is attached to the plane with screws, be sure they are tight.
J.B.

[bgf]

I have modified a cheapo iron plane to work like a dream. If sharpened and used like you think it should be, it won't work on curl maple without tearing.

By grinding the blade vertical to the work, it changed from a slicing action to a scraping plane. Now the plane works on curly maple, I can plane against the grain without tear out.



I didn't make this up, I learned it off a friend.

Brilliant.  I started using planes more, but tear out always stopped me short in some cases. I think I'll get another little plane and set it up like that!  I had been thinking scraper plane anyway...  Thanks for posting.

[Acer Saccharum]

With that trick, you don't have to go out and buy an expensive scraper plane. But you may, if you need an excuse to buy a new tool.

[Dennis Glazener]

Acer,
I assume this would work on a small Stanley hand plane? I have two and would be interested in grinding one as you show. Since I always have problems sharpening any kind of cutting tool Any suggestions on how this should be done?
Thanks
Dennis

[Mark Elliott]

Dave,  I think flexing probably is my problem as I am working on the stock between my vise and end supports.   i will move the stock to my joiners bench and see what difference that makes.

Thanks

Mark

[Acer Saccharum]

Acer,
I assume this would work on a small Stanley hand plane? I have two and would be interested in grinding one as you show. Since I always have problems sharpening any kind of cutting tool Any suggestions on how this should be done?
Thanks
Dennis

Just hold it against the wheel at the correct angle and grind away. The 'correct angle' depends on how it's held in the plane body. Think of it like this: the scraping face needs to be 90 deg to the sole.

Since this is abrasive on the blade, the blades lose their keen edge sooner. So more frequent sharpening is needed. I just touch them up on a fine diamond stone.

[WadePatton]

I have modified a cheapo iron plane to work like a dream. If sharpened and used like you think it should be, it won't work on curl maple without tearing.

By grinding the blade vertical to the work, it changed from a slicing action to a scraping plane. Now the plane works on curly maple, I can plane against the grain without tear out.

...
I didn't make this up, I learned it off a friend.

Brilliant.  I started using planes more, but tear out always stopped me short in some cases. I think I'll get another little plane and set it up like that!  I had been thinking scraper plane anyway...  Thanks for posting.

thanks!  stuff like this makes the dues here seem cheap. 

[Mark Elliott]

I wanted to pass on a tip I received via PM from someone who apparently didn't want to post it here.    It involves putting a slip of paper under the plane iron.    Let me say that I normally stock my rifles on my rifle bench which has a Versa-Vise type vise in the middle with wooden supports on either end of the six foot bench.   That means that a good bit of the barrel channel is unsupported.    I get the chatter around the end support point which means it is probably an harmonic effect as suggested by Dave that would be resolved by moving the stock to the joiners bench.  However,  the joiners bench isn't a perfect solution and I would rather not have to keep moving the stock from bench to bench.

Anyway,  I tried the slip of paper with the stock in the normal position on my rifle stocking bench,  and it worked.   There was still a touch of chatter, but a thin slip of paper got rid of better than 80% of it.    I cut the slip of paper exactly the same size and shape of the cutting portion of the iron.   I was told that if a thin piece of paper didn't work, try a thicker piece.   I don't know if the paper worked by acting as a damper or by closing up the mouth of the plane a bit.   It could have just changed the harmonics of the plane body.   I don't know.   If someone else does know the physics involved,  I would like to know it.

[Kermit]

It's common to get chatter when planing unsupported wood, especially with wild or wonky grain. What you describe as "harmonics" is about right. The joiners bench idea should help a lot. The paper shim idea is probably closing the throat. I've shimmed old molding planes on occasion, and it can get one working again, sort of. Getting a cutter on a molding plane scary sharp is a challenge too. A molding plane can't be expected to hog off great hunks of wood. Think of setting to take a thousandth or two and you'll be headed in the right direction. I preferred using hollows and rounds for moldings, but can't say I ever got to do it enough to get to where it came as second nature.

The wood species you're working makes a difference too. Walnut or H. mahogany can be a dream. Maple not so much.

[kaintuck]

Mark.....maybe taking to big of a bite??...and all of the above info is really good too.....but I get chatter in hard wood with, too big of bite, or to steep of a blade.....
Marc n tomtom

[David R. Pennington]

One of the problems I run into using antique molding planes is that occasional spot with contrary grain pattern. Planeing a flat surface you can usually change the direction of attack and take care of a lot of tear out. With a molding plane if it is a non symmetrical profile you need a left and right to do it.
 I remember hearing about the paper trick "now that you mention it" and have even found old planes with slips of paper behind the irons. I think I even read somewhere once about gluing paper to the back of the iron.
One trick I have used to get around a little knot grain on long slender pieces and it might work on a gun stock is to support the stock material evenly underneath with boards except for the area around the knot and let the piece flex down under the plane in that area effectively skipping the trouble spot and then go back with files or contoured sanding blocks and finish. 

[Kermit]

Actually, increasing the blade angle would help with hard or wonky wood. That's why scrapers work. You can buy some bench planes with steeper angles. I have made my own wood-bodied planes (Krenov-style) with 50 and 55 degree angles. Buying old molding planes you get what you get.