No.5 jack plane blade advancement issue

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tibi

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Hello,

I have recently started to have issues with blade advancement in my Stanley no.5. When I set the cap iron close to the edge (0.1 - 0.3 mm) I am not able to advance the blade below the sole level. If I move it further away, I can advance the blade more by that distance. For practical purposes my cap iron must be 2-3 mm so that I can advance the blade enough. My original thought was that the blade is too short and the cap iron screw does not allow me to advance it any further. So I bought a new blade for Stanley no.5, which is a lot longer than the old one. But the issue presists.

What I have checked so far:
- I have enough space in front of the blade and below the blade. I have tried to move frog forwards and backwards
- blade is sitting firmly on the frog, there is no debris under the frog, or anywhere else on the plane. I have used compressed air to get rid of any debris
- I tried to align frog straight, so it is not skewed
- when I move the cap iron back like 5 mm from the frog, everything works fine

So the issue must have a relation to the relative position of the cap iron to the cutting edge

Do you have any idea what the issue might be?

Thank you.

Tibor
 
Cap iron location slot doesn't quite match position of the adjuster yoke. Maybe from another plane or something. Nothing to do with blade or the rest of the plane, it's simply 2 to 3 mm too short from cap iron edge to adjuster hole
 
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Cap iron location slot doesn't quite match position of the adjuster yoke. Maybe from another plane or something. Nothing to do with blade or the rest of the plane, it's simply 2 to 3 mm too short from cap iron edge to adjuster hole
Hello Jacob,

Thank you, a good tip. It might be the case. However, it worked before and I have recently sharpened both no.4 and 5 at the same time. Should not they have the same cap iron sizes? I might have swapped them.
 
Hello Jacob,

Thank you, a good tip. It might be the case. However, it worked before and I have recently sharpened both no.4 and 5 at the same time. Should not they have the same cap iron sizes? I might have swapped them.
Sounds distinctly possible! Usually things are interchangeable but sometimes they aren't, maybe less so between Stanley and Record for instance.
 
However, it worked before and I have recently sharpened both no.4 and 5 at the same time. Should not they have the same cap iron sizes? I might have swapped them.
That could be the problem if, as you say, you sharpened both irons at the same time. It could be that the cap iron and its matching blade of the no 4, prior to the sharpening only fitted that plane properly; the same for the no 5. In other words you may have, as you suggested, got the blades and cap irons in the wrong combination.

As Jacob said you would normally expect these parts to be interchangeable between one plane and another if they are both the same brand, but perhaps yours are somehow inadvertently or mysteriously 'customised'. Slainte.
 
The distance from the bottom of the slot in the cap iron and the edge of the cap iron needs to be such that it allows you to set the cutting iron close to that edge and lower it down past the bottom of the mouth, the length of the iron is irrelevant. As the yoke pushes down the cap iron, the whole double iron lowers, but if you think about it, the cap iron has to be the right length. What you describe indicates that it is too short, that's why assembling the double iron with the cutting iron lower let's it protrude below the mouth.
 
Cap iron location slot doesn't quite match position of the adjuster yoke. Maybe from another plane or something. Nothing to do with blade or the rest of the plane, it's simply 2 to 3 mm too short from cap iron edge to adjuster hole
That's exactly the opposite problem I had with a newly purchased vintage No 4 where mine wouldn't retract, I asked several eBay sellers of cap irons to measure from the bottom of the adjuster slot to the bottom edge and one was 3mm shorter than mine so I bought it and it works fine now. So the OP may well have a cap iron that is too short.
 
It's a trap for young players - the cutting iron has nothing to do with the limits of blade projection. The blade has a looong slot, it's almost infinitely adjustable.

Issues like this are nearly always caused by the cap iron. As others have said, it's the distance from the yoke slot to the leading edge of the cap iron.

So put your favourite iron into your favourite plane and swap the cap irons to see which gives the best result.

Cheers, Vann.
 
That was the right solution. I have swapped the cap irons today and both my no.4 and no.5 work fine now. Thank you all. I have never thought that Stanley no.4 type 19 and Stanley no.5 type 19 will have a different length of cap iron.
 
I have another issue with my cap iron. I have marked the underside of the cap iron with a blue marker and ground it flat, so that no traces of the blue marker are left. so it should be flat (I had the other end of cap iron hanging below the stone level, so that the edge is undercut). I have also poished the front and the underside. When I tighten the cap iron to the blade, left side is touching the iron, but there is a gap on the right side. What is the remedy for that? The cap iron might be twisted, as I have removed the blue marker completely, so the edge should be flat. I have seen people on youtube using hammer to untwist the cap iron, but I did not have success with this method.
 
I have another issue with my cap iron. I have marked the underside of the cap iron with a blue marker and ground it flat, so that no traces of the blue marker are left. so it should be flat (I had the other end of cap iron hanging below the stone level, so that the edge is undercut). I have also poished the front and the underside. When I tighten the cap iron to the blade, left side is touching the iron, but there is a gap on the right side. What is the remedy for that? The cap iron might be twisted, as I have removed the blue marker completely, so the edge should be flat. I have seen people on youtube using hammer to untwist the cap iron, but I did not have success with this method.
Cap iron not supposed to be flat from top end to the edge. Looking along it from the underside the edge should be a bit higher than the face which meets the blade, so that when they are held together with the screw they spring together with a tight fit closing the gap between edge and blade. This may bend the blade very slightly, until pressed flat to the frog when the lever cap is tightened.
The edge itself should be undercut slightly so that the very front tip is a tight fit against the face of the blade.
 
Cap iron not supposed to be flat from top end to the edge. Looking along it from the underside the edge should be a bit higher than the face which meets the blade, so that when they are held together with the screw they spring together with a tight fit closing the gap between edge and blade. This may bend the blade very slightly, until pressed flat to the frog when the lever cap is tightened.
The edge itself should be undercut slightly so that the very front tip is a tight fit against the face of the blade.

This is exactly, what I was trying to achieve. The edge of the cap iron should be the only point of contact with the blade. Not the whole "edge face". I get that flat, until I tighten the screw, then one side springs off and forms a gap. After the screw is tightened only the very left point touches the blade and all the rest is gap.
 
Actually, after tightening the screw, if I press the cap iron to the blade with my fingers there is no gap. As soon as I release the pressure the gap appears almost along the whole length of the cap iron edge. So the pressure made by tightening the screw is not enough. I also tried to bend the cap iron more in the metalworking vice, but it did not help.
 
Actually, after tightening the screw, if I press the cap iron to the blade with my fingers there is no gap. ....
Should work OK when it's pressed down by the lever cap.
 
Should work OK when it's pressed down by the lever cap.
I had the lever cap already pretty tight, and tightening it more did not help. I have probably found the root cause of this problem. My cutting iron is bent away from the cap iron (0.10 - 0.15 mm gap under the straight edge measured with feeler gauges) - it is convex on the flat side and concave on the bevel side, so that is why it is so difficult to mate surfaces.
 
aha
Perhaps a way to cure would be to put the cutting iron on a steel plate (or anvil part of a vice if you have a metal vice that has one) convex side it up and persuade it with a heavyish hammer (not a panel pin hammer) that little bit you need it to move.
 
So I finally resolved the issue myself. I have persuaded the iron to convex to the other side a bit, so that the cutting edge can touch the cap iron as later suggested by okeydokey.

But the real problem was the cap iron itself. It was formed in a way, that the flat part of the cap iron laid flat on the flat part of the cutting iron. So no spring force could be applied by tightening the screw.

Below there is an illustrational picture. Points B and C were laying flat on the flat face of the cutting iron, i.e. there was no gap, so that tightening the screw applied no force to the point A. I have bent the cap iron to the opposite direcion so the gap is now formed and it applies the pressure to point A when tightening the screw.
1634039612583.png


Problem solved.
 
Well tibi, you have learnt some valuable lessons on cap-irons, so you haven't wasted your time. :)

The situation you described is pretty commonplace on old planes. I think Stanley et al deliberately made the cap-irons so that most of the CI sits flat against the blade when screwed together and the curved end puts sufficient pressure on the mating edge. This causes no or minimal flexing of the blade iron. The trouble starts when for various reasons, you need to re-seat the end of the cap iron on the blade. You don't have to remove much to find you're no longer getting firm contact with the blade. This is easily cured by bending the cap-iron just a little - old cap-irons are thin & "soft" steel which is pretty easy to bend. But do it carefully, if you over-bend the curve you can get into a situation where you've shortened the CI & you run out of depth adjustment - it's all very finely calculated and you don't have to alter the edge-to-cam-slot distance by much to get into trouble, as you've discovered.!

I really like the old-style cap-irons, they use a minimum of material but the design allows them to work very well. It's a well thought-out mechanism, I reckon. If everything is fitted properly, the cap-iron & blade should pull together with no or minimal bending of the blade when the retaining screw is tightened, but apply sufficient pressure to close the end securely against the blade. It doesn't need a lot, the lever cap pressure will add a bit more & it should be plenty enough for normal use if everything is right:
12 cap iron double bend.jpg

The trend started a few years back to make very heavy replacement cap-irons, the idea being to add more stiffness to the blade/cap-iron assembly. The cap-irons are similar to the ones used with very heavy blades on old planes, they have a single bend to bring the edge to bear against the blade. This it does, for sure, and there is no problem with thick blades, particularly the very thick blades of old, but they don't work so well with the thin Stanley/Record blades, imo. When tightened down, these caps can put a very distinct curve in the blade!
11 cap iron single bend.jpg

The lever-cap won't 'straighten' something like this, it only applies pressure at top & bottom of the assembly, leaving all or most of the curve intact. This may or may not matter - depending on the type of wood you plane & how heavily you're cutting, you may not notice anything untoward, but I've found it can certainly promote a tendency to chatter in some situations & I think is best avoided - better to have it so the blade assembly sits nice & flat on the frog.

So when tinkering with cap-irons, there are a few things you need to keep in mind....
Cheers,
Ian
 
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