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Andre
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Why do you plan to re-scrape your knee way? That's a big job. Were you taking it apart to scrape anyway, or are you going to scrape it because of this mishap?
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Stuck Knee On Jhead!!
- Thread starter Neiko
- Start date
- Joined
- Dec 27, 2014
- Messages
- 4,055
And the material probably wouldn't support (strengthwise) the effort anyway.
Drill a hole and punch the gib upward.
- Joined
- Dec 8, 2013
- Messages
- 2,651
I don't think you want to try to move both at once. I think you need to get the gib to move upward with respect to the knee. Prying on the knee is just going to wedge the gib tighter.
Would it be feasible to cut off the protruding bit of gib and then drill all the way through the remainder lengthwise?
- Joined
- Mar 3, 2014
- Messages
- 634
Gibs are soft and will deform. The end my already be mushroomed and will need to be dressed as best as possible.
If there is any down travel left for the knee then the gib should be blocked and the knee forced down.
Just put the jack screw back in or build a cradle so it cant drop to disaster.
Use a good penatrant oil on both dovetails. Kroil is the best if you can find it. Keep it wet for a couple o days.
Then with a bloody big rubber dead blow or the best you can come up with " a soft block of wood" hit the knee down.
Use light blows as a start. Hopefully you can rotate the head out of the way and have solid metal at the center of the knee close to the column.
If you must hit above the knee dovetails then "tap" one side n then the other.
Tap it good and walk away for a bit. The penatrent might work in deeper.
Don't get in a hurry.
If there is any down travel left for the knee then the gib should be blocked and the knee forced down.
Just put the jack screw back in or build a cradle so it cant drop to disaster.
Use a good penatrant oil on both dovetails. Kroil is the best if you can find it. Keep it wet for a couple o days.
Then with a bloody big rubber dead blow or the best you can come up with " a soft block of wood" hit the knee down.
Use light blows as a start. Hopefully you can rotate the head out of the way and have solid metal at the center of the knee close to the column.
If you must hit above the knee dovetails then "tap" one side n then the other.
Tap it good and walk away for a bit. The penatrent might work in deeper.
Don't get in a hurry.
- Joined
- Feb 26, 2016
- Messages
- 11
Welp,I got that sucker out today!! IT took a Blue Flame wrench, a 14"long air hammer driver and some True Grit!! I cut the smallest hole i could cut so it would be easy to fill with brazing rod. Knocking the gib loose at first with a 18" punch and 5 lb hammer and it snapped off... I was at wits end. I grabbed the long driver and air hammer and drove it up as far as i could. put a strap on the knee and lifted it up off the column like it was never stuck!!! good news is the ways are in good shape and not wore slick... almost all the Biax markings are still visible and no gulling!! So now its clean, paint, and get a Gib coming so I can get this back together! Thanks for the advice and words of encouragement!!!
- Joined
- Feb 26, 2016
- Messages
- 11
As in scraping the knee... it looks good, ill bring the straight edges home tomorrow to check it out. now the table and the knee ways will need to be scraped. so that will be the second step after the knee is back together. I'm looking into haveing the table blancher ground since it has 70 years of being beat on by everyone who could!