repairing/rehabbing the pins of a mortise gauge

[Zahid Naqvi]

So I acquired an older, what seems like rose wood, mortise gauge with the brass strips and screws. Problem is the pins are really worn out. From initial inspection I can't really figure out if there is a way to extract these pins and reinsert them after a good cleanup and sharpening or even replacing. So is there a way to bring one of these back to life?

[Gordon Harner]

What I have done is, do what works to loosen up and remove the existing pins. Use twist drills of the same diameter as replacements. They can be ground to any shape you like. I have also been told that a finishing nail can be used as a replacement but from my experience nails are made of material that is too soft for any extended period of use.

[Zahid Naqvi]

the problem is how to remove the existing pins. I have tried to wriggle them out using a plier but they are not budging. Not sure if they are just friction fitted or was any glue involved. Once I get the p[ins out I can probably put replacements in relatively easily (I got plenty of broken drill bits).

[Jim Koepke]

Depending on how the gauge was made or repaired in the past you may have to use a small punch to remove the old pins. If you do not have a small punch, one can be fashioned from a small nail.

I am always careful when doing something like this. The piece that is holding the pin needs to be fully supported. I will use something heavy with a hole slightly larger than the pin. Start with very light taps. Try to determine if the mounting hole for the pin is tapered.

The pin could also be soldered into a brass piece.

jtk

[Zahid Naqvi]

I looked closely at the mortise gauge and the pins do not go all the way through. So how do I get the sliding brass strip (on which rides the movable mortise pin) out. When I unscrew it all the way it hit a point after which the thread starts spinning freely. The strip is inserted inside a sliding dovetail so the only way to take it out would be to slide it pout the back. Maybe I can take some pictures later and post them.

[harry strasil]

just file the pin off till its flush with the brass piece, then drill a new hole and drive in a finish nail or whatever cut it off the right length then using a file with a safe side sharpen the pin to a taper.

[Zahid Naqvi]

just file the pin off till its flush with the brass piece, then drill a new hole and drive in a finish nail or whatever cut it off the right length then using a file with a safe side sharpen the pin to a taper.

Duh!:o Why didn't I think of that before. If all else fails that is exactly what I am going to do

[george wilson]

But,can Zahid drill out a steel pin(which probably has some temper in it) from a brass part it is mounted in? The drill would not stay on the pin,but would wander off into the brass. I would mount the brass part in a milling machine where it can be held very rigidly,and milled out with a carbide end mill. The same way I mill out broken HSS taps.

If you want me to do this for you,PM me for my mailing address,Zahid. No charge. If I have to use a cutter a bit larger than the pin,I can turn out a brass sleeve drilled to take a new pin,and press it into the hole tightly.

[Zahid Naqvi]

thanks George, but I'm not too attached to the gauge, just want to figure out the mechanics for future reference. As you know I like buying old tools and rehabbing them into service.

[Johnny Kleso]

I'd drill a bigger hole on the other side and knock out the pin..
Then fill the hole with a dowel and glue after you insert the new pin..

Do you know how big the old pin is?
A broken drill will work much better than an old nail..

[Nixon Roger]

I'm guessing you have a Stanley 77 (or similar) marking/mortise. Seems like all of them have a worn out pin on the sliding bar which makes me think that one isn't hardened.

Here is a link to some pictures (http://www.goantiques.com/scripts/images,id,465698.html#image2)
If you cant drill out the sliding pin, you would have to remove one of the brass ends to get the sliding bar out.
If you find a good solution, I'd like to hear it because I have a few of these myself. My solution was to buy a new gauge. :)

[Tony Shea]

Istead of starting a new thread thought I'd ask this question here. Hopefully it will get some views. But I have a couple older marking guages of similar styles and they have their screw stop mechanism missing. It looks as if there is some sort of brass peice that is missing that should be between the bar and the head which the set screw should make contact with. Neither of these marking guages will take a setting as they will not tighten up. Hope I explained it ok. Is there a fix of some sort that I can do to make these guages useful to me. I've thought about a penny but seems that would be too finiky as it would want to fall out. I'd like something that will stay put like what should be there originally.

[Johnny Kleso]

If you have some soft metal you can file a piece to size or use a piece of hard wood.
Its so the screw doesnt make gouges in the beam and after time it will all gouged up and when you tighten it it will move off loaction.
A wooden GIB will work. It shaped kind of like this 0____0 the bump ups stop it from falling out and is flat on the beam side

PS:
If you find some brass the correct thickness you can just bend the end up to lock it in the gauge

[Pat Barry]

Zahid - a picture would be worth 1001 words in a case like this. If the pins are attached to the brass piece its probably by silver solder or possibly rivetted in place. The temperature for silver solder process would be too high to be done while assembled to a wooden part and likewise if it was rivetted that would have to happen before assembly, therefore the brass part and the pins would have to have been a sub assembly in which case it has to come apart. One other possibility is that the hole in the brass piece is very tight fit to the pin and the brass was heated with a torch to expand it, then the pin was inserted and the brass was cooled, shrink fitting the pin in place. That's an extremely robust method.

I assume you have grabbed the pin with a vise grip and then tried to twist and pull it free. Since its not coming I would focus on removing the entire brass piece and assume the pins will come along. Then examine it closely - right now I suspect it was the heat shrink method that was used and this is easily reversible and non-destructive to replace a pin.

[Frank Drew]

With no evidence at all, I always assumed that the pins were driven into tapered holes from the back side of the brass.

On one of my marking gauges, the pins had been filed down to barely nothing by a previous owner but they still leave a line, so "worn out" pins don't necessarily mean that the gauge can't be used effectively.

[Zahid Naqvi]

Ok here are some pictures. I can see that the front pin is probably a single pin that goes through the arm and provides points at both ends. The sliding pin on the brass plate is attached somehow(friction fit or brazed etc.). I am curious about the spiral discs. It seems these are rivets which have been surrounded by decorative elements. There also is some kind of holding arrangement (threaded sleeve) at the back end of the arm through which the threaded bar passes and moves the adjustable mortising pin. The problem is if I keep unscrewing the brass rod it hit a point after which it will not unscrew anymore. I suspect the threaded bar sliding through the sleeve hit the end and they did not thread the last 1/4" or so. If you look at the first picture it seems a rivet is holding the nut/sleeve under the sliding bar.

192032
192033

[harry strasil]

I can see both pins on the top side in the first picture, that is about the length of the pins on all the gauges I have seen, why do you want to replace them? It's usable as is!

[Zahid Naqvi]

Harry, for starters the two pins are of unequal height, plus when I try to sharpen them there is not enough height in the pins for me to stick a file in (as it starts marring the wood). So I was thinking if I can extract the pins I can sharpen them off the marking gauge and then re-insert them in a finished state. More than that I am just trying to figure out the mechanics/build of the gauge.

[george wilson]

You can grind the teeth off the edge of a file,and round it just a bit. The grinding marks need to run the length of the file rather than across it. The file will not entirely leave the wood unabraded,but it will drastically reduce the amount of marking. If you want to really make the file's edge "safe" also hone it on a stone to remove the grinding marks. Don't forget to slightly round the edge also,or the sharp corners of the safe edge will scar the wood.