Help with troubleshooting wooden coffin smoother

Dominic Greco

Member
Messages
149
Location
Bucks County PA
Hi gang
I just finished cleaning up this Union Warranted Coffin Smoother and have been having some problems getting it to work properly. I took a lot of photos in the hopes that the more knowledgable of you could offer me some tips.

This Union Warranted Coffin Smoother was purchased at a local flea market for the kingly sum of $5 and it came with a very nice Butcher Iron. But at the same place I found a Buck Brothers Iron of the same size. The seller threw that in as an incentive. So I can swap out one or the other. Both of these irons had their backs flattened and polished to a mirror finish. The bevels were hollow ground and sharpened to the point where they could cut end grain pine with little effort.

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There were some cracks on the body that I repaired with a bit of epoxy and some sawdust. But any that were in non critical areas I left alone. Near the abutments there were some stress fractures. But these were glued and clamped up overnight. In the photos below it LOOKS like there is a crack on one "ear", but it's really filled with epoxy and sawdust. I flattened the sole on some sandpaper as well as flattening the back of the wedge. I also cleaned up the points of the wedge to get rid of areas where chips would snag. Where I sanded, I gave the body a coat of BLO and allowed it to dry before waxing. I made sure that I didn't get any oil or wax in the abutments, bed, or ears.

When I installed the iron/chipbreaker assembly and wedge into the smoother I noticed that the wedge was VERY tight in regards to the sides. I believe that this would account for the cracks near the abutments. I sanded the wedge so that I got a nice even fit. I also took care to assure that there weren't any gaps between the wedge and the cheek. You can see this in the highlighted areas of the photos below.

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After all this tuning up, I decided last night to give this little beauty a test drive on some nice straight grained cherry. However, when I went to use it I ran into all sorts of problems.

1.) The original iron just fits the mouth opening. And I had thought that I re-ground the bevel so that it was 90 deg to the sides. But this iron has slightly tapered sides. So it's close, but not dead on. This makes getting an even "reveal" pretty difficult. I ended up swapping out the Butcher Iron and replacing it with the smaller Buck Brothers Iron. You can see the amount or room between the sides of the iron and the sides of the mouth in the last photo.

2.) I can't get the wedge to hold the iron in place. When I hit a particularly knarly or tough patch of grain, it moves. From the photos you can see that I have the wedge as tightly fit as I can get it.

3.) When I tap on the back of the iron, the iron moves and the chip breaker DOESN'T! This is with BOTH the Butcher AND the Buck Brothers Irons! So the amount of iron showing increases each time I tap the back of the iron!

4.) Last but not least; I get chips clogged in one corner. I'm thinking that the points of the wedge need to be shortened so that the are sitting on the flat of the chip breaker. If they are near the end where it curves, then there is a place for a chip to get stuck.

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I've been reading through Whelan's "Making Traditional Wooden Handplanes" as well as Finck's "Making & Mastering Wood Planes". These books helped a lot. But I would really appreciate input from members who tune up and use wood hand planes.
 
I'm a bit out of my depth with wooden planes, but a couple of things come to mind.

As far as the blade shifting during use - it doesn't look like the wooden wedge is seated along the length of the chip breaker. Instead, it looks like it bears at a single point on the chip breaker, fairly far back from the throat. Ideally, you'd have the wedge seating along the length of the cheek and the top of the chip breaker. You might try cleaning up the grunge on the chip breaker as well - it could make it more difficult to get a good grip on the blade/breaker assembly.

I think i'd regrind the Butcher blade at the proper angle, hone it, and put it back in the plane. It looks like the Buck has a lot of extra room on the sides. If the Butcher fits better, i'd stick with that one. If it's not clearing the shavings, i'd look at the wedge more closely. It looks like the throat opening on the toe side is tapered back sufficiently. You may just need to close up the gap at the sides of the cutting iron, either with the better fitting iron, with some new wood inserts glued into place, or by modifying the shape of the wooden wedge - you may need to make a new one.

If you can pick up a copy of "The Fine Art of Cabinetmaking" by James Krenov, he dedicates a good part of the book to making your own wooden planes, including a coffin sided smoother. He's known as a strong pragmatist and is somewhat famous for his tutelege on wooden hand planes. I think you won't go wrong consulting guru Krenov.

You'll get it humming along. Have fun with it and keep us up to date with the solutions.

Paul Hubbman
 
I have a very old coffin plane and may be the reason of the blade moving away from the chipbreaker, apart from what has been mentioned by Paul may rest on the fact that maybe this plane originally was not designed to hold an iron+chip breaker set.
Are you sure that this is the original blade it should have and that it had a chip breaker?

Mine never had a chipbreaker, and it works like a charm.

I agree with Paul that the better the blade fits on the throat (widht wise) the less prone will the plane be to be clogged by shavings
 
Hi Dom, Guys,

I'm pretty late chiming in here, but I'll put in my 2 cents worth anyway.

You've got a few different things going there. The gaps with the Buck blade look fine to me. When I look at the woodies in my shop, those gaps are probably narrower than most. If the Butcher is the original iron, the reason it's so tight is that the plane body has shrunk across its width over the years. I have one here that I had a heck of a time removing the iron from, and it's almost certainly the original iron because it's got a complex profile ground in it.

That little gap between the horn of the wedge and the plane body appears to be your main problem. The horns don't have to be extremely close to the cutting edge, but they do have to be smooth and gap free.

I'd make a new wedge. The plane body has the slot for the cap screw in it, so the cap iron seems to belong there. Perhaps the wedge is not original. Even if it is original, it ain't doing its job ;) Anything you do with the existing wedge is going to remove material and eventually you'll have to chuck it anyway. Now, it just happens that the only tutorial I ever contributed to the forum was on making a new wedge for a woodie. It's here

As for the slippage between cap iron and blade, I wonder if that cap screw and/or the surface of the blade around the edges of the slot aren't worn out. If the gripping surface of the cap screw doesn't look dead flat and smooth, take a small file to it.

Mmmmm... that's the best I can come up with.
 
Coffin smoother wedge rebuild update

Hi gang,
I finally got a chance to mess with that wedge I made for my old wooden coffin smoother. I used walnut for the new wedge and followed the directions I found at the Norse Woodsmith site. Side note here: That is one doozy of a site! It is just chocked full of great information!

I'm glad I let this sit for a while before I went at it again. After making (2) wedges and not having either work I figured it was a good thing to leave it alone for a bit. As it stood, one of the wedges wasn't as bad as I had thought. So all it took was some careful chisel & rasp work.

It turned out that the abutments are not quite at the same angle. So I had to tweak the wedge a good deal to make it fit perfectly. Before this I used a belt sander to narrow the sides of the iron by a hair, and flattened/polished the chip breaker. But it was getting the wedge to fit right that did the trick.

Here's some shots of the smoother after trying it out on a piece of cherry.
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After I was confident that I had the wedge sized correctly, I cleaned up the corners and used a rasp to steepen the incline on the inner "ramp". After all the work I did making sure they fit, I left all the sections that contacted the abutments alone!

Here's a shot after I tried the smoother on some ash.
cofnsmthr3a.jpg


The next think I'm going to do is either laminate a new sole onto this plane, or just install a insert at the mouth. Either way, I have a nice piece of pear that will work.

BTW, I was examining the front of the plane this afternoon and noticed the maker's mark. It's partially worn away but I could see a star and some letters. Anyone know of a plane maker that uses a star in their logo?
 
Ian,
Thanks for the input. Check out my reply above and you'll see that I ended up doing what you had suggested.

No sweat, Dominic

I knew there was a good chance you had it sorted out by the time I wrote my reply.

That $5 plane is sure getting a lot of love! I think what you're doing is great. There's no better way to learn how a thing works than to find a broken one and get it working again.

I think it won't be too long before you start making a new woodie to use that spare plane iron in ;)
 
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