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pepecon
03-09-2005, 07:01 PM
I am try;ing to make a brass hammer from an 1.625 dia. pc of round brass. The handle hole has to be oval to fit the wooden hammer handle which measures .720 X .940. I am having a hard time rough drilling the hole . I tried a 1/2 inch drill bit and followed with a 5/8 end mill. I got a lot of grabbing which moved the mill head and even broke a 5/8 4 flute end mill. Does this procedure call for a special end mill. I tried a 2 flute end mill and that was grabbing worse. How much should be drilled before using an end mill ?

Rustybolt
03-09-2005, 07:38 PM
You might be feeding too fast. Try drilling a 64th under the size you want .010 or .005 would be better. One 16th on a side is just too much if you're trying to plunge the cut with a RH spiral RH cut endmill.

egpace
03-09-2005, 07:41 PM
You need to break the drill cutting edges for brass, (zero rake) otherwise the drill will grab upon breaking through whatever your drilling. As far as the milling goes, try an endmill smaller than the hole you've drilled and try plunging down slowing removing material till you get close to the size you need, then run around to finish.
Have fun,
Ed

PS If working on a knee mill, feeding up with the knee will ease the break through isses.

[This message has been edited by egpace (edited 03-09-2005).]

wierdscience
03-09-2005, 08:21 PM
Yep,you need zero rake on brass and cast iron.

precisionworks
03-09-2005, 09:33 PM
Would it be easier to drill a round hole and turn the handle round to fit?

Forrest Addy
03-10-2005, 01:40 AM
Drill the hole a bit undersize. Install the endmill and use it to step sideways plunging vertically to cut with the end only. Take about 0.025 at a bite (maybe less depending on the size of the ednmill and its extension. Once you have the egg shaped hole roughed out you can skim around the periphery taking 0.010 a side to clean it up and make it pretty.

Hammer head handle holes (say that fast three times) are double tapered (about 1 in 12) to wedge snug on the handle and so you can wedge the end to swell the wood tight in the head. Next question is: how are you doing to cut the touble taper?

If the handle is properly fitted to the head it's amost impossible to loosen the handle without deliberate abuse.

Anybody?

[This message has been edited by Forrest Addy (edited 03-10-2005).]

Paul Gauthier
03-10-2005, 12:46 PM
How fast is your spindle turning, perhaps too slow. Crank it up.

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Paul G.

[This message has been edited by Paul Gauthier (edited 03-10-2005).]