Questions from a chookshed engineer

[jatt]

Hi all,

Fotos arent the best, done on a fone camera.

Got this piece of tooling that I came with my mill.    

As one can see from the foto one of inserts was damaged before before it came into my posession ie its chipped.  Can only assume they are carbide tipped as they didnt like the water cooled slow turning grindstone I used on them.

After attacking a piece of rusty steel with my 20 mm endmill I used it to clean up the resulting swirl marks created from this process.  The resulting piece is shown to the edge of the last foto.

I started off on a really low speed and wasn’t happy with the result.  Progressively increased the speed over several light cuts, up till around 1200 odd rpm, which was as fast as I was game enough to run it.

Can I assume this is some kind of facemill?  Is this the kind of task that its designed to do?  should I run it that fast?

[Stilldrillin]

That`s a facemill........ To me, they look like h/s inserts, not carbide.

Will need a tool & cutter grinder for sharpening edges....... Or, after sharpening, the inserts will need setting all to the same protrusion using a dti......

Personally I would use it as a flycutter, with 3 spare tools! 

If it`s 3" dia (and h/s inserts)....... Cutting steel, I would keep to around 100 - 200rpm.

David D

[Bernd]

David D is right, it's a face mill. Also agree that the inserts look like HSS.

Easiest way to set those to all one higth is to put the arbor in the spindle, loosen the screws that hold the inserts and bring to bare against a flat plate. Tighten screws and then check each blade with a DTI.

Bernd

[Darren]

If they are HSS you gotta get that speed down,

A good rule of thumb is for every doubling of cutting edges you can double the speed, but only to a point with HSS.

[Baldrocker]

Bernd is spot on for adjustment method, Ozmestore on ebay usually carry hss spares,
if  they are original cutters they appear to be made of unobtainium, ie: very
brittle (thats if you spin the quill depth adjuster the wrong way while running  ).
BR

[jatt]

There is a destinct line on my inserts bonded to the leading edge.  Thats what made me think of carbide in the first place.

Might try and foto the chipped one so its more obvious. 

Stilldrillin  --- Like the idea of using it as a flycutter, with 3 spare tools!

Thanks for all of the quick replies.  Dont look too close at my vertical bandsaw jig in pic 3.  Rushed job one nite after work.

[miker]

jatt, did that thing come with a Hafco Mill?

One came with my HM-46 and I ran a file across one of the inserts which proved to be really soft. NOT High Speed Steel (HSS)!!!!

I threw the thing up on a shelf and ordered a set of endmills and ER32 Collet Chuck with 20 collets from this company http://www.ctctools.biz/servlet/the-38/ER32-MT3-MK3-COLLET/Detail

Rgds

[jatt]

miker -- yep its a Hafco SM MD40XP. 

As yet I dont have anything else to finsh off a piece, so I figured I would have a crack at using it.  I should measure the inserts and find something better to replace em with.  For the moment tho, I will just have to make do. 

Do the inserts on your "thing" appear to have some sort of other metal bonded to it?  I cant get a good enuf foto to explain it better.  Whatever it is its fairly hard as the stone on the slow speed grinder didnt like it too much.  Got one of those cheapie water cooled jobs.

Yeah my ER32 collet chuck spends most of its life on the mill, rarely comes off.  With 19 collets to choose from, its the drill chuck that spends its life on the shelf.

[dsquire]

Bernd is spot on for adjustment method, Ozmestore on ebay usually carry hss spares,
if  they are original cutters they appear to be made of unobtainium, ie: very
brittle (thats if you spin the quill depth adjuster the wrong way while running  ).
BR

Baldrocker

Just wanted to let you know that you can run but you can't hide when it's time to wish you a

    HAPPY BIRTHDAY 

Hope you have many more

Cheers 

Don

[jatt]

yep same from me HAPPY BIRTHDAY