Thread: Chipbreaker Recommendations for Thick Plane Blades

If the blade is too thick, the yoke cannot reach through the screw slot to the chipbreaker, which controls adjustment. The problem - or solution - does not lie with the chipbreaker, but with the blade being too thick.

There are two solutions.

The first is to extend the nub of the yoke so that it is long enough to connect with the chipbreaker. This requires some welding or brazing. Alternately, one of the UK woodwork shops (Woodwork Heaven?) sells a special replacement yoke.

The second method is one that Rob Cosman developed, which is a block that is screwed into the screw lot to connect with the yoke. Google for his website.

Regards from Perth

Derek

Thanks Derek. I think Rob's chipbreaker is the type of solution I was looking for. He also suggests widening the mouth.

It seems he doesn't sell just the chipbreaker separately unfortunately. I don't need any more blades! I think I already probably have something like 2 blades per plane.

Ill email him about it.

Jim Davey sells the Cosman kits. I purchased 1 a little while back for one of my smoothers. I also had to file the mouth a little. Nice jiggers !

Originally Posted by derekcohen

If the blade is too thick, the yoke cannot reach through the screw slot to the chipbreaker, which controls adjustment. The problem - or solution - does not lie with the chipbreaker, but with the blade being too thick......

Derek - while not contesting this statement, I'm not entirely sure if blade thickness per se is Theodor's problem. If he didn't have this problem with the 'original' blades, then yes, I'd suspect the adjuster cam isn't properly engaging the slot in the chip breaker due to blade thickness. But while Hock blades are a bit thicker than the original Stanley & Records, for sure, they don't usually prevent adequate adjuster engagement with the cam slot on the chip breaker unless you have an out-of-tolerance adjuster cam. I have put Hocks and LV blades in a variety of old Stanleys, and have encountered no problems on that score, though I have read of people who have. So while it's certainly something to consider, I interpreted this a little differently:

Originally Posted by Theodor

.... I'm running into problems in that I can't screw out the blade enough for thicker shavings due to limitations of the chipbreaker. Plus I can't move the frog forward/back otherwise the blade hits the front of the mouth.....

I need a bit more information to make a diagnosis. Can you move the blade assembly a small distance either side of 'neutral' (adjuster wheel roughly at the centre of its stud), but the blade stops moving even though you have plenty of thread left for the adjuster wheel? If this is the case, it is a short cam problem & changing to another chip breaker isn't going to do anything to fix that. The only 'proper' fix is to build up the end of the cam a few more mm. It's a bit fiddly, but not all that hard, to braze a bit of metal onto the tip of the cam. If you do it neatly & clean it up well, the new bronze tip actually works more smoothly than the original.

Or are you running out of thread, with the yoke dis-engaging from the wheel before the blade extrudes? If that's the case, the problem is more likely a mis-match of cap iron and frog assembly. I discovered on my first attempt at making a new cap-iron just how critical it is to get the distance from cam slot to the end that contacts the blade correct. This is what determines where the edge of the blade will be, and believe me, you only have a couple of mm to play with (remember Luke's thread where he filed off his LN chip-breaker a wee bit and then couldn't extend his blade far enough?). Wear & tear & wide manufacturing tolerances mean you can strike problems if they happen to be additive, and that could be your lot, but it's possible someone has substituted the original chip breaker for one that is a fraction shorter, or that it has been filed down. Whatever the case may be I suggest you check that aspect out as well. With the chip-breaker set somewhere near your 'standard' setting on the blade and the adjuster wheel around midway between hitting the frog & falling off, the cutting edge of the blade should be about level with the sole, or slightly extruded. That will allow you to withdraw the blade safely for transport, etc., and still extrude it far more than you'd ever need to.

Like you, I'd be reluctant to take a file to the mouth of a decent old plane. The range of fore-aft frog adjustment on old planes isn't huge, but it should be adequate to cater for any blade within reason - i.e., something in the vicinity of 3.5mm or so. What is actually preventing the frog from being moved back a bit?

Cheers,

Hi Ian

Good point. It depends on the thickness of the blade to point in one direction or the other. I did not assume that the issue was with a Hock blade, per se, since Theodor "thick A2 blades (e.g. Hock)".

Theodor, how thick is the blade you are using?

Regards from Perth

Derek

Ok. I'll try to show you with my thickest blade. This was one of the "tombstone" blades made by someone on these forums in the mid-naughties. It comes in at 3mm thick.

image.jpg

Here it is setup on a type 11 Stanley No. 7. I believe these are the original chipbreaker and lever cap. The chipbreaker is approx 0.3mm from edge.

image.jpgimage.jpg

The frog is sitting pretty flush with the mouth .. so the bevel at the back of the mouth continues up the face of the frog front.

I've extended the blade so I take a reasonably fine shaving. You'll see that the depth adjustment is pretty far back, although there is still a reasonable amount I could continue to extend the blade.

image.jpg image.jpg image.jpg

The yoke is still engaged rather reasonably at this point. And I still have sufficient space at the mouth for a deeper cut.

Actually I might just check that...

And strangely enough I can take a rather thick shaving and the yoke is still engaged.

Somehow between changing out the used blade (same 'tombstone' variety) with this sharpened blade, the plane seems to be setting and working properly.

I feel like a real goose now. I have no idea what I've done differently. Even setting the chipbreaker a mm back wouldn't have made such a difference.

Originally Posted by Theodor

.... I feel like a real goose now. I have no idea what I've done differently. Even setting the chipbreaker a mm back wouldn't have made such a difference.

Theodor - I wouldn't feel too embarrassed, I think we all have occasional claims to feathers.

The point is, you did strike a problem, and it would be nice to understand what caused it, for curiosity's sake as well as future avoidance. The only thing I can think of on the spur of the moment is that you didn't tighten the cap-iron screw sufficiently and it may have been slipping - have had that happen once or twice over the years.

As I'm sure you are well-aware, there is a huge amount of 'slop' in the Bailey mechanism. When replacing a freshly-sharpened blade assembly in any of my planes, I wriggle it a bit to make sure the lateral adjuster slot is seating properly (you are usually soon made aware if it's not when you try to tighten the lever-cap!), and I'm still surprised after all these years at how much the blade will move up & down before it's locked down, even when both adjustment cams have engaged. I usually let it sit at its most extended point, with lots of extrusion, so that I can flip the plane over and check the lateral adjustment before setting depth. I do notice that when it's all set & ready to go, the adjuster wheel always seems to be a bit further forward or further back than it was before I disassembled it. I just put that down to the slop in the system.

Anyway, all's well that ends well....
Cheers,

Thanks Ian for your kind comments. I did check my No. 5 1/2 as well. I adjusted the frog a fraction forward and that doesn't seem to have issues either. Thank goodness I checked before considering grabbing a longer yoke or even a new plane iron and chipbreaker set.