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View Full Version : What am i doing wrong ?



davidh
04-18-2009, 06:55 PM
sometimes when taking cuts on different metals from right to left ( i can;;t see it would make any difference), i get a "pile-up" of metal in front of the cutting edge of the tool. i thought i have sharpened the tool correctly but maybe not ? and i can always file it off but. . . . . i don;t think i should need to do that.

what am i doing incorrectly ?

davidh (the old guy)

juergenwt
04-18-2009, 07:20 PM
What kind of cutting are you doing? Milling, drilling, turning etc and what kind of material are you cutting? What kind of tool are you using? What feed and speed?

speedy
04-18-2009, 07:24 PM
Tool height too high?? Cut too deep?? Feed too fast??

gr8life
04-18-2009, 08:15 PM
Assuming you are using a lathe you need to grind a chip breaker.

danlb
04-18-2009, 08:25 PM
I interpret that as a build up to the LEFT of the cutting tool's edge. As if he is pushing metal out of the way.

If that's the case, there might not be enough side rake for the depth of cut.

Dan

aboard_epsilon
04-18-2009, 08:46 PM
think you're undercutting...and throwing a big burr in Front of your work ..yes

just use a scrap piece of steel and observe what happens when you move your tool post around to different positions and cut .

undercutting will happen if you are using those boat shaped cutters ..and can only be really stopped by having the whole tool pointing 90 degrees to the work .........then your carriage will hit the chuck before you get to the end of the work

sharpen different angles on the tool ...so that it is advancing into the work ...with the tool pointing forward....but the edge is sort of 90 degrees ish for starters

have a look at tool sharpening profiles given on various sites .......but be careful in how you intemperate them ...as many are drawings for tools meant for old style rocker type tool posts ....were the tool points up in the air .

my advice on 90 degrees is just to get him started and understand what is going on.,

all the best.markj