Skate moves in plow plane

[Corneel]

Recently I aquired a nice German plow plane. There is no makers mark on the plane itself but the iron has a mark from J.P. Arns a well known smithing factory in Remscheid. As usual with wooden plow planes, there is a bit of a problem with the rearskate. When aquired it wasn't inline with the frontskate. The result is that the plane is quite unusable because it tends to see-saw back and forth on the skates.

So I filed them flush. But under wedge pressure the problem reappears. So before I continue with draconic modifications I seek the wisdom of this forum. How do you go about to rectify this situation? The rear skate is attached with four countersunk woodscrews.

 

[Corneel]

Pictures. The plane itself:



And the problem with the skate.

 

[AndyT]

I've been and looked at my wooden ploughs with this problem in mind. Most of them are riveted through the stock and are rock solid, but two are fixed by screws. On the better one there is no play between the top of the skate and the bottom of the groove it fits in and the screws hold tight because their countersinks fit snugly into matching countersinks on the metal skate. No problem there. But I have one other, which has been repaired, whose rear skate was loose, making it out of line with the front, maybe like your one. I fixed it just by tightening the screws down.

So, assuming yours used to be OK, I think most of the improvement you want would come just from tightening the screws. If they won't tighten (because wood has crumbled away) you might need to partially plug the holes with splinters of wood, or even sawdust and glue.

If the skate has been rocking in use, it might have locally deepened the groove it fits into. If so, you could glue in a long sliver of wood, then carefully scrape it down to the right size so that there is no gap when the skate is in its right position.

I expect that you will then need to file the front part of the skate to line up straight again.

 

[AndyT]

Having now looked at your pictures I see that yours does not have a groove, so when I said groove, think rebate. I expect that the construction with a groove would be superior. Either way, the top edge needs to be supported by wood all along its length, so there is less strain on the screws.

 

[lanemaux]

Sorry to seem thick here , but I don't see a major problem here. As plough planes are meant to hog out material rather than create a surface , the inequality between the skates would be about what I would use for a depth of cut per stroke. Perhaps a bit extreme , but then again in it's intended use we aren't going for wispy shavings. I think it looks reminiscent of the setting height difference between jointer tables exaggerated a bit. I know little on the subject but this is what it looks like to me.

 

[Corneel]

At the moment it is better thenin the picture. I filed the skates so they were even. Then when I wedge the iron tight it moves a bit again. Maybe like Mike sais I shouldn't worry. The other idea I had was to replace the front screw with a thicker one so it sits tight in the hole.

As it was it was quite unusable. I couldn't get a usefull shaving. It was either digging in or lifting out of the cut.

 

[Derek Cohen (Perth Oz)]

Hi Kees

The first thing you do is fix the skates so that they do not move. This may require plugging the existing holes and re-drilling them. It sounds as though the screws were shifting.

Only then do you file the skates.

The skates must be coplanar otherwise the plane will either cut too deeply (nose dive) or not cut at all.

Regards from Perth

Derek

 

[AndyT]

Sorry to seem thick here , but I don't see a major problem here. As plough planes are meant to hog out material rather than create a surface , the inequality between the skates would be about what I would use for a depth of cut per stroke. Perhaps a bit extreme , but then again in it's intended use we aren't going for wispy shavings. I think it looks reminiscent of the setting height difference between jointer tables exaggerated a bit. I know little on the subject but this is what it looks like to me.

I know that seems logical if you sit and think about it, and you are not the only one to have had that thought, but in practice it's just not true. Planes work only when the part before the blade is in line with the part behind.

 

[Corneel]

Right. I'm going to look for some thicker screws. I have to glue the fencerods into the body too. As usual it's more work then what I thought it would be.

 

[lanemaux]

Oh well , as stated , not my field really. Good to know more than I did before . Thanks guy's.

 

[Corneel]

Succes! I got some 5 mm woodscrews and the rear skate is now solidly attached. Works wonderfully.