#7 chipbreaker question

[Daniel Rode]

I recently acquired a Stanley #7. I never thought I'd need one because I have a power jointer. I was wrong. I use the #7 as my primary method to flatten stock and the power jointer is collecting dust. It's not easier but I much prefer the process and it's really not that much effort.

It's working really well. However, I'm occasionally getting shavings between the iron and the chipbreaker. I flattened the edge so it appears to meet the iron evenly and the bevel is at a angle so the front edge makes contact. If it makes any difference, I'm setup to take thin, but not gossamer fine shavings and I have the chipbreaker set about 1/64 from the iron's edge.

What's the best method to go about debugging this issue? I'm going to recheck the chipbreaker to be sure it's perfectly flat, but what else should I look for?

[Jim Koepke]

For me it is easiest to look between the blade and the assembled chip breaker from the side. They are held up toward a light source to see if any light can be seen anywhere along the mating surface. Then the front of the mating edge is inspected to make sure there isn't any burr or fissure that may trap a shaving. If this doesn't revel any flaw, the next step is to make shavings until some jam. Then inspect the area where the shavings jam.

Also some of my chip breakers have benefitted from having the "hump" lightly stropped toward the mating edge. This is usually followed by a rag impregnated with furniture polish.

The area where the shaving is deflected needs to be free of nicks, burrs or bumps that may snag a shaving.

A magnifier will surely help.

jtk

[Reinis Kanders]

It can happen if your blade is getting duller and you are going against the grain and trying to take too thick of a shaving for the chipbreaker setting.

[Doug Bowman]

For me it is easiest to look between the blade and the assembled chip breaker from the side. They are held up toward a light source to see if any light can be seen anywhere along the mating surface. Then the front of the mating edge is inspected to make sure there isn't any burr or fissure that may trap a shaving. If this doesn't revel any flaw, the next step is to make shavings until some jam. Then inspect the area where the shavings jam.

This is how I do it - sometimes even though you flatten the chipbreaker edge it still may not sit square on the iron - (as a matter of fact none of mine did) - I use a 600 grit DMT to knock down the high side and then make a few flat passes and then check it again

[Mike Cherry]

I've heard of people using small strips of paper placed on the blade face. Then tighten the chip breaker and try to slide the paper out from between the two. If you can remove the paper, there is a gap that could allow a shaving to get clogged.

For what it's worth, I have had a hard time removing the burr when tuning old Stanley chip breakers. You gotta work it back and forth until you remove all trace of it. Hope this helps

[steven c newman]

When a chipbreaker comes through the shop. I will try to get a knife edge where the chipbreaker rests on the flattened iron. Sometimes, I use the beltsander, holding the chipbreaker along the side. Angled the top down a few degrees. Once there is a thin, knife edge, I then polish the rounded upper part. I like them mirror bright. A thin edge when clamped down to the iron will deform just a hair. It closes any small gaps. While "sanding" the knife edge, I keep checking the fit to the iron. I need to hold the cb at 90 degrees to the sanding belt, and the tail end about 10 degrees or so lower than the surface of the belt.

Seems to work for this old No.7c..
Jointer plane.jpg

[don wilwol]

all good advice so far. Also make sure the back of the iron is nice and flat.

[Daniel Rode]

Thanks for the advice. I'll see if I can figure it out this weekend. The slips of paper are a good idea. That should let me find any tiny gaps.

[Niels Cosman]

Thanks for the advice. I'll see if I can figure it out this weekend. The slips of paper are a good idea. That should let me find any tiny gaps.

I've swapped out most of my original chipbreakers for Hock blades "improved" style breakers. However before the swap, I mated the chipbreakers by lapping the mating surface relieving the rear mating edge slightly so just the front edge made contact. Then I marked the mating surface with a sharpie and reassembled the blade lightly with a strip of some very (probably 800 or1000) wet dry sandpaper in between. I pulled out the sandpaper to mate the surfaces under tension. I did that a bunch of times until the sharpie was gone along the front edge. That seemed to work well enough.

[Jim Koepke]

I have used Dykem blue in the past. Paint the back of the blade then rub the chip breaker over it. Where the blue transfers to the chip breaker indicates the high spots that need to be worked.

Not sure if a sharpie would transfer as well as the dye.

jtk

[david charlesworth]

Paper is quite thick. Possibly 0.004 thou.

Cigarette paper should be thinner maybe 0.001 thou.

However thin shavings are 0.001 thou, so near perfect fit is required.

David Charlesworth

[Brian Holcombe]

My paper recommendation was originally made as 'newsprint' and is meant for trouble shooting. Paper is about .003", newsprint probably about .002", so if the paper is sliding through the assembly you know you have problems. It is helpful for locating the problem area. i

I dont use anything to check, personally, except the scratch pattern on the blade and chipper. The chipper is typically undercut so that the leading edge is contacting the blade surface.

[Allan Speers]

I had a similar problem once on one plane, no matter how I filed it.

A simple solution, if the idea doesn't bother you: Wax the blade's top well and let it dry. Clean the chipbreaker's edge really well, then apply a thin coating of JB Weld to it's mating surface. Keep a little of the leftover epoxy-mix on your mixing surface, and after an hour or two, feel it to see if it's reached a "plastic" state. - dryish to the touch, but still malleable.

At that point, mount the breaker on your blade and tighten it all the way. 24 hrs later, pop off the breaker, & trim away the excess that squished to the sides. You'll have a perfect match, and it will last a long time if you don't abuse it.

[Bob Glenn]

Not as technical, but try moving the chip breaker back from the cutting edge. It's worked for me. Bob

[david charlesworth]

If the blade back and the C/B underside edge are both worked across a flat stone, they should both be flat and fit perfectly. The C/B edge benefits from some undercut or clearance angle.

A prop for its top end, which is about 3mm lower than the stone surface, creates this clearance angle. The tip is worked with a short stroke near to the edge of the stone so that the rest does not catch on the stone.

A diamond stone is convenient as it is likely to be flat.

There was an old technique, where a scriber was drawn across the C/B blade junction. The scriber point deformed the softer C/B metal to create a fit.

Although this makes some sense I cannot bring myself to try it!

David