cap iron too short?

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

samhay

Established Member
Joined
10 Aug 2017
Messages
323
Reaction score
36
Location
Peak District
It seems I may have worn out the cap iron on my old Record 05 1/2.
I recently purchased a new iron for this plane as the old (probably original one) was getting a bit short. Setting the new one up - which is from Ray Iles, and is very nice - it would appear the cap iron is too short to work properly. The new iron doesn't yet have any camber, so I had a play setting the cap iron close to the edge. However, the hole in the cap iron fouls on the frog screw well before I can extend the iron far enough to protrude from the mouth of the plane.
To get the plane working, I have had to set the cap iron back a good 1/4" from the edge of the plane iron. This feels a little gauche, even for a jack plane. And yes, I will grind some camber into this at some point, but it would be nice to have some wiggle room to allow the cap iron to have some function.
It would be nice to fettle the original cap iron to make it work, but I'm not sure there is much I can do to 'fix' it, is there?
Assuming the answer is no, does anyone have any recommendations for a new (or new to me) 2 1/4" cap iron to suit an old 05 1/2 plane?

Thanks.

Edit.
A picture might help. It's fouling where the red arrow indicates.
plane.jpg
 
Last edited:
I can't think of a real fix for this that doesn't involve significant metalwork moving the threads and the slot at the top (for the adjuster). That's not practical, of course.

Even if you remove the obstacles to the post (make that bottom slot longer), you'll end up in the cap iron screw (hitting the screw/post sticking up) and modifying that is a one-time affair, even if you can finagle it - and still will come with adjuster issues further up.

Solution? Unless you like peining and welding, a different cap iron is in order.
 
Literally ran into this last week on a new off brand plane that I was going to set up as a ruse. It was at least as bad as that and on top of that, the rest of the plane was rubbish. I stole the iron from the plane and threw the rest in the garbage (only $20 for the whole thing).
 
Thanks, I figured that was the case, but wanted to sanity check it first.
As 2 1/4" irons are unusual, it is not trivial to find a replacement. I probably have a spare 2 3/8" iron, so maybe I can make that fit with a little filling.
 
Maybe file off the metal from the cap iron at where the arrows points to, ie where it's touching the screw.
 
If the cap iron fitted with the old blade it should with the new, unless it's very different - much thicker? File the hole.
In my experience an old blade "getting a bit short" tends to mean it's probably only got 20 years left in it, maybe just put it back!
 
If the cap iron fitted with the old blade it should with the new, unless it's very different - much thicker? File the hole.
In my experience an old blade "getting a bit short" tends to mean it's probably only got 20 years left in it, maybe just put it back!

You're upside down. The issue is the new cap iron, not the old iron. If the cap iron isn't drilled for the right distances from the post and the adjuster pawl, there's no way to fix it without metalwork.
 
It's the plane iron that is new and the cap iron (chip breaker in the US?) that is orginal, so Jacob is on the right track.
Except, I bought the new iron as I was struggling to adjust the depth of cut, and I suspect the issue was that that cap iron was fouling with the old iron too - I will look at this on the weekend. Either way, I would like to get this working better, so it looks like a new cap iron is needed.

Edit. I don't think filing the slot in the cap iron is a good solution as I would need to find about 5mm, and that would not leave much meat between the slot and the cap iron screw hole.
 
Have you got the frog set too far back? It's intended to be dead in line with the mouth so that the blade sits firm on the frog AND sits on a few mm of the thickness of the mouth, for max support. People fiddle about with them all over the place!
I'll measure a cap iron tomorrow - I've got a 5 1/2, a 6 and a 7 and the blades/caps are all interchangeable
 
I have a 051/2 which is fitted with a Stanley blade. The only thing that is a slight problem is that the adjuster fork didn't engage fully in the cap iron slot, (too much slack.) To overcome this I narrowed the slot by Aralditing a small piece of ali plate on the underside of the cap iron to close the gap.

Nigel.
 
...... I bought the new iron as I was struggling to adjust the depth of cut, and I suspect the issue was that that cap iron was fouling with the old iron too ....

I think you've settled the diagnosis there, it would seem you had the same problem with the original blade. The cap-iron is the fundamental part, not the blade. As already mentioned, the distances between its edge & the lever-cap screw & cam slots are crucial. The existing cap-iron is either a substitute or someone has filed off the end, for reasons only they would know. Five mm is a huge amount to remove, and would bring the curve back to the point it could no longer b made to contact the blade (there are visible dings evident in the pic, so it may well have been "re-shaped" to get the edge back on the blade). Whatever, as others have said, there is no satisfaactory cure for "too short".

...... I don't think filing the slot in the cap iron is a good solution as I would need to find about 5mm, and that would not leave much meat between the slot and the cap iron screw hole....

Agreed, & not only that, your adjuster won't work properly. The cam that engages the slot in the cap-iron has a quite limited range of travel for smooth adjustment, just a few mm. Even if you extend the lever-cap screw slot, getting an extra 5mm from the adjuster will be nigh-on impossible. If the cam slot is out by even a couple of mm it's a pita, because the cam binds in the cap-iron slot before you get the blade in a working position.

I'd just make new cap-iron, but for the reasons mentioned, they have to be made accurately, so if you aren't confident you can do that, your best bet is to find a new/old one. Personally, I prefer the old style curved cap-irons to the "single bend" style that most after-market suppliers offer, but they obviously work.....
Cheers,
Ian
 
Thanks All.

Jacob - Frog is set properly. Unfortunately, early 5 1/2 and 05 1/2's have 2 1/4" irons (probably because this was common in earlier wooden planes?) whereas newer versions share the 2 3/8" irons of the larger planes. I discovered this trying to swap irons at some point in the past - at least in my case the 2 3/8" won't quite fit in the mouth.

Nigel - thanks, that's a useful tip. The backlash has always been pretty aweful in this plane (for as long as I've had it anyway), so anything to improve it would be great.
 
If the cap iron fitted with the old blade it should with the new...
You're upside down. The issue is the new cap iron, not the old iron...
Jacob is right (and DW is wrong). The relationship between the irons and the mouth is set by the cap-iron. A new cutting iron does not effect that relationship.

Have you been using the plane (with that cap iron) up to now? If so you should be able to set it up the same with the new cutting iron. Things that DO change with a new (thicker) cutting iron include: the reach of the yoke (Y-lever); the length of thread holding the lever-cap screw; and the size of the mouth of your plane.

A bloke on the Aussie forum did a bulk buy of M2 irons about 5 years back. He didn't understand the relationship of the cap-iron the the mouth. He made some last minute alterations to the cap iron CAD files before sending them to the laser cutter. I have two useless 10 1/2 cap-irons as a result, and a whole bunch of other people ended up with cap-irons they couldn't use.

Your idea of filing down the width of a 2 3/8" cap-iron is a good one, but first measure the distance from the yoke hole to the mouth. Either the frog, or the cap-iron, is slightly off (or both). You don't want to file down the wider cap-iron only to find it's the same length as the existing one.

Record changed their No.05 1/2 planes from 5 1/4" to 5 3/8" in 1938 - so your plane is one of the most desirable (and best finished) era. Note that even your frog screws are nickle plated.

Cheers, Vann.
 
The thickness of the blade doesn't explain the end of the cap iron being 1/4 inch away from the sole of the plane unless it's literally thicker by 1/4 times the square root of two.

Something is amiss here in setup perhaps, but the cap iron hitting the frog screw is a cap iron problem. If the iron was the problem, as in too long below the slot, the iron would be hitting the frog screw and sticking out of the plane. If the cap iron could be set close before, it should be easy to set it very close now. Perhaps less than the thickness of the iron divided by the square root of two.
 
I've just been out with the calipers to have a closer look.
The new iron is ~0.5mm thicker than the old one. The yoke can still reach the cap iron, so this shouldn't cause too much trouble.
I compared the cap iron to others in my collection. It is ~3 mm shorter than the cap iron in my 4 1/2 (aligned to the frog screw and yoke cut out), which is set up with minimal camber as a smoother. I expect this would just work in the 05 1/2 if it wasn't too wide.
The spare cap iron I have is significantly shorter, so I expect it's in my parts box as it doesn't work! I'll have to keep an eye out for another one.
There is quite a bit of camber on the old plane iron and I have tended to set the cap back about 3-4 mm from the edge (in the centre). I've just checked and if I try to wind the iron out to take a heavy cut, it does foul on the frog screw, so I expect this is only going to cause trouble if I ignore the problem and stick with the old iron.
 
Ron Hock can supply a capiron for your plane.

Production variations on cap irons give different lengths from slot to cap edge. I have encountered several of these.

If you can work out a length that works, Ron will supply. NB Yoke is most efficient when square to frog surface.

Best wishes,
David Charlesworth
 
Ron Hock can supply correct cap iron for your plane.

There was variation over the years of cap length. Length is measured from slot to front edge.

If you can work out this dimension Ron can supply one.

Best wishes,
David Charlesworth
 
Not sure what people have on hand to work with, but the type ron makes is something that others can make fairly easily as it's just a slab of mild steel.

This may be a good opportunity to take a shot at making one. But it would require something suitable for a cap screw (or donor cap screw) and thread tap for cap iron.

If there is a suitable 2 3/8" cap that's the right length, though, it will take little time to sand the sides off since they're not hardened (on a power sander) - or file same.

I make mention of this only because cap plus shipping plus vat from california to England is serious money to solve something that may be far easier to solve locally.
 
Thanks David. That's all good to know.
I'm tempted to try to make one. If it doesn't work, I guess I have a couple of options.
What type type of steel should I be looking for and any tips?
 
Personally, I'd use some kind of high carbon steel like 1080 or o1 if I were going to make a slab type. You can make the slot with small drill bits, files and a small dremel burr.

But if you find a good fit wider cap and narrow it, I think that's most practical.
 

Latest posts

Back
Top