Modifying the shank of a boring head - Abdrehen eines Ausdrehkopfes

hi welcome back to today we have this is the shank of wool hope the boring head small boring head with a more tape of foreshank and this this is not mine somebody in an online forum asked if there was somebody out that could machine this shank down to a diameter of 20 millimetres and shorten it so he can check it up in an ER 32 collet and there was a lot of fussing around in the thread with the discussion about machining the shank down it might be hardened or it might be way too hard to machine or it might explode or whatever and I stepped up to a person and said I will machine it down for him I'm going to cut it off with cutoff disc with the angle grinder and we're going to the lathe and we're going to machine or grind with the to post grinder me shank down to a diameter of 20 millimetres and put a nice finish on it so he can clamp it in his colored Chuck so you see it's pretty simple chopped and it shouldn't take too much effort and yeah there were a lot of people out there that said this thing might be hardened and in fact it is but it's not super hard in fact the file grabs it pretty good so we might get away with just turning maybe we don't have to break out the tool post grab but we will see okay I have the shank that we just cut down with the angle grinder tucked up in the leaf and I put some grass shim stock between the chance and workpiece and now I chested it for run out so it's as true as possible here on the and on the yen 50 dovetail and also very very true running on the shank side so I set up to dial indicators to check if it's at the same time while was shifting around the Chuck on the flange and knocking the piece in place with a brass drift and as you can see the new old stone to move very much first of all we're going to face off the end very carefully and put a 63 Center in there so it can support this piece with the Life Center I don't want to turn this only clamped in the truck unsupported because of the pretty hard material it's not really glass hard but it's tough enough to cause problems if it's not chucked up very rigid in the machine so we're going to support it and for that we need a 60 degree Center I'm going to start out with one of my shop mate brace carbide bits see how it goes also I'm going to drop a rack on the leaf bets because I don't want your heart and chips to be on there okay that went very well we got a pretty decent surface finish the interrupted cut chipped my my turning tool but we will rewind that that's the beauty of race car bite with a insert tool you would have lost one cutting edge of a insert that maybe has only two cutting edges and inserts our five bucks and more so way to turn okay I swung the tool post around and now we're going to put a little six degree chamfer or thirty degree depending on which angle you're looking on into the bore the central bore of the shank and that's for the life center and we're going to use one of the last inserted carbide tools I have it's this boring bar okay that's enough of a 60 degree count or for the tip of the live sender to engage the workpiece okay we set it up with the live Center and I'm going to make a witness mark over here within a distance of 45 millimeters oh yeah that stuff makes horrible mess of stringy chips low feet yeah I know don't touch the chips okay that's too dangerous with these stringy chips I will go back to a tool with a chip breaker so I don't get this curly mess I'm not going to pull on these by hand that's the easy way to remove a finger okay I roughed it down and did a first finishing pass and I'm down to twenty point five millimeters that's 0.5 to go and we're going to take two passes 25 hundredths of a millimeter each pass so I get each I see if the cup is consistent also this is a tool with a pretty big radius so I get at the shoulder a nice radius and no stress rise area where the shank might break off okay not the best finishing work but it's okay I think I'm going to run I'm going to polish it later on very likely with some super finishing paper or super finishing band let's measure this we have twenty point two four five on the shoulder and and 20 point twenty point twenty point three nine eight what twenty point two three eight at the other end so it's almost perfectly cylindrical and we're going to take another cut down to 20 and we leave it heavy to hundreds of a millimeter to give us some meat for finishing I think the last step is to break sharp cornice and I don't have a carbide tempering tool something to use my community turning tool rotated around by approximately 45 degrees okay let's check it once and for all on the shoulder end we have nineteen point nine nine five and on the outside end we have nineteen point nine nine three millimeters so this is pretty much cinder cool and weigh in the tolerances that are needed to hold it in er thirty-two collet Chuck so let's take this out of the late and go back to the bench okay we're back in the bench and we have the shank of the boring head here I'm very happy how dust came out and as expected the material of the shank was hard it was not super hard it was not like high-speed steel or a or another cutting tool but it was still pretty hard and pretty that was hard on the car by - it interrupted cut on the facing broke the edge of my of my carbide lathe tool which was grounded a very aggressive angle and - very delicate points so it wasn't too surprising that the Coronet chipped but anyway I got it done I got to turn down to 20 millimeters it's cylindrical and the surface finish is not too lousy so I think that little project is done and I'll send it back to the owner and hope he's happy with it thank you for watching

Channel: Stefan Gotteswinter

Views: 25,773

Rating: 4.9438992 out of 5

Keywords: wohlhaupter, boring head, feinbohrkopf, ausdrehkopf, hard turing, hartdrehen

Id: c9X3nmSbQvg

Length: 16min 53sec (1013 seconds)

Published: Sun Jul 05 2015