Damaged 60 1/2 block plane thread - replacement?!

[Fergie 307]

I'm not sure about this, but those threads look like a different size to me as already said. They also look the same pitch, but the steeper helix angle implies a double start thread. It does actually look like that, but can only really be ascertained by examination. It makes sense in the the parts would move apart when the thread was turned. It also complicates things for anyone making one. Certainly not insurmountable, but just more complicated. Any maker would need to examine the whole plane preferably to take sizes and threads off it.

I think chai latte is correct, it looks as though they are different threads simply because, although the pitch may be similar or the same the different diameters make it appear different.
From my point of view, if I have the parts in front of me then replicating them is easy. I don't really need to know anything more.
If it was a case of making a missing part from scratch, then I agree you would want the whole thing to be able to understand how it is supposed to work.

 

[Corset]

not sure thats worth the effort of repairing, lots of poor ones go cheap on ebay and just take the part of another one. thats a personal view but i have restored 50 or so over the years and certain things just arent worth the effort.

 

[Fergie 307]

not sure thats worth the effort of repairing, lots of poor ones go cheap on ebay and just take the part of another one. thats a personal view but i have restored 50 or so over the years and certain things just arent worth the effort.

Oh agree entirely, depends on the quality of it, or maybe sentimental value.

 

[Amplidyne]

I think chai latte is correct, it looks as though they are different threads simply because, although the pitch may be similar or the same the different diameters make it appear different.
From my point of view, if I have the parts in front of me then replicating them is easy. I don't really need to know anything more.
If it was a case of making a missing part from scratch, then I agree you would want the whole thing to be able to understand how it is supposed to work.

I was simply thinking that if I were making the whole thing, I'd want to be able to try the threads for fit. Especially if they are non standard.
In my mind, the threads are near enough so that a similar pitch on a different diameter wouldn't show that much difference in angle on the helix. Also if you try to follow the threads round, they look as if they don't match a single start. Also how does the thing work?
However as I've said, I may hopefully be wrong.

 

[Fergie 307]

I am coming at it from the assumption that the tool has been used by the OP for some time, and worked correctly until the threads stripped?
If that is the case then a new part or parts with intact threads should get it back into use.
Two things I don't understand.
1 why the different diameters? If they were significantly different, say 1/4 and 7/16, then I could understand, although would still be interesting to know why. But when they are so close it just seems rather pointless.
2. The female part appears to be brass. If that is the case then I am struggling with how a brass nut can do that much damage to what appears to be a steel thread. I wonder if there is something else going on, is it rubbing against something for example?
Ok ignore point 2 having looked at a video of one being stripped down I can see it is steel.
This is a still, not very good quality but can't make my mind up if the larger thread is actually left handed, which would make much more sense.
Someone on here must have one, this video is of a Stanley, which appears to be identical to the OP's.

 

[Fergie 307]

I was simply thinking that if I were making the whole thing, I'd want to be able to try the threads for fit. Especially if they are non standard.
In my mind, the threads are near enough so that a similar pitch on a different diameter wouldn't show that much difference in angle on the helix. Also if you try to follow the threads round, they look as if they don't match a single start. Also how does the thing work?
However as I've said, I may hopefully be wrong.

Not disagreeing with you. But if they have to be posted from Scotland, where the OP is, then sending the whole thing a tad pricey.
I can make a replacement to the exact dimensions to within pretty tight tolerances, so ought to be ok.
But I agree it would definitely be better if he could find someone locally, and take the whole thing in.