Plough gauge stuck roller

[plusone]

Thanks for all the replies so far. 

the wing nut does loosen but the thread on the bolt is damaged at the end so can’t get it totally off. 

Not sure if these next set of pics helps any but I think the outer brass tube should roll. 
I’ll try WD40 to start with and see if I can get that thread working enough to remove the wing nut. 

[dikman]

That makes more sense, there is a shoulder in there that the washer under the wingnut should tighten against. It should be possible to fix that thread with either a fine hacksaw blade or a suitable file (at least enough to get the nut off) and heat should be enough to break the roller free of the gunk inside. Mine, btw, has a nylon roller.

[DrmCa]

Looks like a brass tube over the steel shaft.

You could take a triangular file and clean the thread up. I wonder if it's been the previous owner's way of peening the nut in place. There are many strange people in this world.

The surface of the roller needs TLC as well.

Edited January 16, 2022 by DrmCa

[dikman]

More likely the thread end was held by a pair of pliers while someone overtightened what's left of the wingnut? 

[DrmCa]

Which reinforces our opinion that the roller did not rotate since.

[Bruce H]

It might be missing a spring washer at the end of the roller? (Make a leather washer for replacement)

One might try soaking the parts in vinegar for cleanup & rust removal then hammer it with oil.

 

[chuck123wapati]

 

12 hours ago, plusone said:

Thanks for all the replies so far. 

the wing nut does loosen but the thread on the bolt is damaged at the end so can’t get it totally off. 

Not sure if these next set of pics helps any but I think the outer brass tube should roll. 
I’ll try WD40 to start with and see if I can get that thread working enough to remove the wing nut. 

if you want to save it and don't have a good knowledge of this type of work or the tools take it to a machinist. They will do what is needed to get it off and cleaned up for you. and or make you a new shoulder bolt. your going to need heat oil and a hammer and punch and vice at the least. Don't try and twist on it with pliers or the brass will be ruined it already appears to be marred but repairable.

[fredk]

Just cut that bit of  bashed up thread off. Its obvious that its not needed. The wing nut can be replaced  with a thinner lock nut

There seems to be some hammer-bashing damage to this tool

 

Edited January 16, 2022 by fredk

[bruce johnson]

i have had a few with that design. It is simple design but not very common. Normally the height is adjusted with a vertical thumbscrew. On yours the wing nut is loosened so the bolt/ roller can go up and down in that slot for different leather thicknesses. Also there is a slotted head on the end of the bolt so you can grip that end with a screwdriver while you tighten or loosen the wing nut.. The bolts are are machined down at the thread end of the bolt so the shoulder of the bolt binds on the fence, not the roller. The brass rollers are usually thinner walled than this. 

If I was to fix it here is what I'd do. Cut that broken wing nut off and have a machinist make you up a new long shouldered bolt, get some brass tube that will rotate on the shaft of the bolt. Add a washer and  wing nut and you are in business. I have found working on these old tools it is generally faster, easier, and cheaper to make or get new parts made than to try to cobble up the last guy's screw up. 

[plusone]

After some hot oil, gentle tapping, vinegar and bicarb I’ve got the roller working like the day it was made. 
Blade is sharpened, about to try my first cut with  

I’ll tackle the handle at some point  

Thanks everyone for your advice.