soften metal,,,??

   I been buggin ole Coke on procedure to dis-assemble the rotary cylinder on the Mark IV,,,and he has been a great help,,,
 I got a question for the gurus on tempering metal. The cylinder has 6 allen headed ,,1/4" pipe plugs that have to be removed to access some pins that have to be removed. One of the pipe plugs got buggered up and allen started slipping on plug,,,,ARGGgggg,,,!!!
  What is the procedure to "soften" the plug in order to drill it out,,,???

Softening hard steel takes heating it red hot and cooling it slowly. With the screw in the parts its going to cool fast. But sometimes that makes it come out easily because it expanded while it was hot and jelly soft and the surrounding metal didn't let it expand so when it cools its smaller than it was and so can come loose.

For drilling a left hand bit can be handy, first it puts a force on the screw to remove it from the threads, and then when it catches its as good as an easy out that is easily broken in hardened screws.

Gerald J.

can ya weld a nut or something else to the plug? I'd try that before drilling,, heat and maybe tac welding a sacrificial wrench to the offending plug? I'd really study the darn thing before drilling,,, but my drilling out broken studs, nuts etc., usually don't go well

Not that it would do any good, but I would also use a hammer and punch in the screw. Then try to turn it out. Then when that doesn't work, and it won't, then drill.

Joe, I've had very good success taking a brazing tip and heating it red hot. Let it cool all he way and then give it a try. If you have messed up the threads it's drill and tap time as already suggested. 

Before you go drilling it out take a tig welder to the center of the plug   warm it up. Then grab a metric Allen wrench and drive it in normally will come out with out problem.

Be careful with carbide. It's extremely hard and, there for, very brittle

desertjoe,
Weld a nut on if you can sounds like a good first try since you say it has moved a few turns.
   If it comes down to drilling it out it will take a lot of pressure to get a masonry drill to drill hardened steel the carbide tip just doesn't have the right edge ground on it for cutting steel.
   Cobalt drills are harder than regular High speed drills but not as brittle as carbide so are a little tougher, keep the speed low and use some oil.
   Dewalt has cobalt drills you can probably find them in a big box store.
   I have also drilled hardened steel with Hi-Roc drills or 2 flute carbide drill, can be done dry speed can be faster.
   I have burned thru hardened tool steel with these with sparks flying.
A BIG word of caution though if using any carbide as thendrix said these are hard and brittle and can break easy so if you get a piece of carbide broke off in the piece you have a real problem.
   Good luck    

Well Joe you got plenty of suggestions and no doubt they've all worked one time or another. But nobody mentioned diamond tipped bits. I didn't want to say anything about them cause I was afraid you'd go into sticker shock and keel over. But they will work.

   Well,I went out this mornin armed with all these great suggestions and just knew thet soab was comin out,,,NO two ways bout it,,,,,,,Took and put a good sharp on my best 1/4" drill bit and doused it up good with some tapping fluid and slow drilled a perfect hole thru the center of the  plug pretty as you please,,,,til I hit the HARDENED tool steel pin that are behind the plugs,,,,&*^^%$^^,,,,I machined me a "pin" to try to drive the hardened pin on into the cylinder but no dice,,,, the pipe plug is only bout 3/8"  long so could not use an ease out either,,,as the  the dang hardened pin keepin it from goin deep enough to grab on the pipe plug,,,%^&%$#@$%^*
   SO,,,,out comes my trusty MIG and like several here suggested,,, I welded a nut around the plug,,,and screwed it out pretty as you please,,,WOW,,,DANG,,,talk bout a BFJ  just for this little bitty pipe plug,,,,,Many, many thanks for all the support, Guys,,,
   I've decided to remove the whole cylinder as I prolly should replace the top and btm seals,cause you can bet your last can of Black label they WILL leak if I don't,,,,!!

   NOW,,,I need some input on who or where to contact bout getting these seal kits,,I've read several places that the M/F 50 and 52 are same size,,,?????


Edited by desertjoe - 29 Jul 2016 at 3:58am

    Thanks Jay IN,,,I'm gonna call Minn-Par this mornin and sure hope I can talk with ole John there as Gary did not seen to want to look into the issue with me when I last called,,,,,
   I have 3 different manuals on the Mark IV and one on the MF 52 A,,,and after comparing them and trying to develop a list of PN's from the books,,,they are all different,,,!!
 The tag on the backhoe has a SN of 1A 686 AC,,but the section for cylinder used PRIOR to MK IV 2A-1248 is NOT the cylinder I have,,,,!! Yet another section of the book for SN MKIV 2A-1248 thru 3A-1355 DOES appear to be the cylinder I have,,,???,,,BUT   the part numbers are different yet,,!! SHEEESH,,,,,!!!
  In tryin to compare with the MF book,I do not see a pic of the cylinder I have,,there some similarities  in the barrels,  Dang,,I'm sure hopin ole John at Minn-Par can help,,,,cause at this point,,,I;m like Little Red riding Hood,,,,,,

    WHY,,,,YOU,,,,!!!  YOU,,,,!!!,,Shameless,,,!!!,AW CHIT it ain't no use tellin you nuttin,,,heck,, you don't listen noways,,,!!!!
    Actually,,,,I wasn't alludin to her be'in pretty,,,,Aw Heck,,,you ain't gonna believe me either,,,,,,,
    To get back to matters at hand,,,,,,,,I DID NOT DO A CHITTIN bit of good on the backhoe all day,,,and I am pissed very much,,,,,, I was tryin to get one of the  big 1 1/2" nuts holdin the cylinder to the frame,,and wouldn't you know it,,,,that soab galled'ed up bout halfway and after messin with it for a few HOURS,,I finally cut the friggin nut off,,the other nut must of seen the fate of it's twin and it gave up and came right on out,,, Got them nuts out the way but I been messin with tryin to get the cylinder broke loose from the splines on the swing frame. I heated and heated and finally gave up and came inside,,,,
 Shameless,,,you got any tannerite,,,??? Gosh Dang,,I am pissed'ed good and need a cold Black label,,,,,,,

about as helpless as this lill flamen RED?


 Are ye sure theres not some stinkin little set screw hiding somewhere? or simply need to put it in a big enough press?