Broken knee gib

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This obviously goes along with my refurb thread, but I selfishly hoped to get more eyes and replies in a separate thread than buried in the refurb.

I seem to have a broken knee gib on my B'port clone. The gib is removed, the knee is off the base. I was a little surprised when I pulled the gib because the screw was not in a notch you could adjust. It appears the gib broke at the notch.
20220609_093637.jpg

20220609_093626.jpg

In my estimation this is not a horrible place to break it, if it just has to be broken. I also don't think this is a good situation to leave alone. Doesn't the gib require the notch for adjustment and removal? If I put it back as is aren't I just waiting for it to lock up?

Further, I assume fixing this one is a much better idea than replacing it, especially since I don't have equipment or knowledge of scraping. So, how do I fix this? A piece of cast brazed to the end beyond the notch?

What are my options?
 
The notch is necessary for adjusting and removal, yes. I'd fix it before I replaced it. Just like you states, braze on a piece beyond the notch, but I would probably try and make it just a little thinner than the rest of the gib to keep it from affecting its use. More or less so it is just there for adjusting and removal.

The gib itself is only like $100 or thereabouts, but it will have to be ground and then scraped. "Fixing" this one seems like a no brainer.
 
Fix it. Braze it if you can.
If you can't then make a washer with an arm to contact the relieved area.
This arm can have a small peice of stock welded to it, if you need to add depth.
Yes, yes I have done this.
I worked on a Daewoo A20 lathe yesterday, while disassembling the cross slide to repair the screw/ nut I found where I had done this years ago it has worked well and I will be using it when I assemble it.
Business owners decide how much time/money they can or are willing to spend.
I will be back there tomorrow and If I remember will take a picture.
 
Question, what material can I use to braze to this? I'm sure this is some flavor of cast iron, but I can't put my hands on any to use right now. Can the end be simple cold rolled steel? I guess I'm looking for options to decide how hard I have to look for material.
 
Build that end up with a brazing rod so you have plenty to work with and machine it down to what it needs to be just clean it up real good out heat to it to cook out all the oil it soaked up over the years
 
sdelivery said:
Regular brazing rod (brass)
Click to expand...

DAM 79 said:
Build that end up with a brazing rod so you have plenty to work with and machine it down to what it needs to be just clean it up real good out heat to it to cook out all the oil it soaked up over the years
Click to expand...


Let me clarify my question. I was planning on using silicon bronze as the filler, and using my TIG welder. What I was trying to say is that I can't put my hands on a small piece of cast iron to weld to the end of the gib, and was wondering if I could use cold rolled steel and braze a small piece of that to the cast.

From a response I'm thinking it may also be possible to simply build up with the brazing rod and machine the notch.

Do I need the steel piece at the end or just build it up?
 
Is there enough travel in the adjuster to just cut a new notch in the gib?
 
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