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View Full Version : Best alternate use of an endmill



cucvzuz
08-08-2011, 02:51 PM
The other day i needed to clean up a hole I cut with a 3" hole saw, I needed 3.25" for a pump mount.

What to do?

Use a boring head right?
Well that would have been great if my 2" DBL-202 head went big enough. All i could get was 3.125" and all of my 1/2" boring bars were hopelessly dull or chipped.

Now what?

It was time to get creative!

I was looking a 9/16" 4flt endmill. and it offered the additional offset i needed. It was far more rigid than my long (3") boring bar, and it had a great cutting edge on it.

It worked better than any bar i have ever used. With no chatter.

I will probably never use a regular boring bar in the head ever again!

http://i141.photobucket.com/albums/r58/cucvzuz/P8081149.jpg

http://i141.photobucket.com/albums/r58/cucvzuz/P2085122.jpg

http://i141.photobucket.com/albums/r58/cucvzuz/P2085123.jpg

Black_Moons
08-08-2011, 02:58 PM
Good trick, although im not sure it has the proper relief for that really.

What you could of done, was use the cross hole in your boring head.

Another good one is a standard HSS bit holding boring bar in the cross hole, And a longish HSS bit in the boring bars hole.

I also would'nt be above* puting a flycutter body into a boring head! Bet it would be reasonabley rigid.


*Term meaning its dirty, but I would still do it.

cucvzuz
08-08-2011, 03:07 PM
Good trick, although im not sure it has the proper relief for that really.

What you could of done, was use the cross hole in your boring head.

Another good one is a standard HSS bit holding boring bar in the cross hole, And a longish HSS bit in the boring bars hole.

I also would'nt be above* puting a flycutter body into a boring head! Bet it would be reasonabley rigid.


*Term meaning its dirty, but I would still do it.

the relief seems to work good if I turn the two fluts parallel to the boring head slide.

JoeFin
08-08-2011, 03:30 PM
What you could of done, was use the cross hole in your boring head.


Thats what I was thinking too

Rather chip $8 inserts on a boring bar then put wear spots in $30 - $40 end mills

Not trying to throw rocks at your ingenuity cucvzuz, I'm just turning into a miser in my old age. Honestly I would have programmed the hole in my cnc and cut out the contour of the hole with a 1/2 end mill

Frank Ford
08-08-2011, 05:27 PM
For shallow blind holes, I sometimes drill and bore with a center cutting end mill in a tool post mounted chuck on the lathe. First with the end mill centered, then increasing hole diameter by moving the cross slide and plunging, I can drill and bore with no tool change:

http://www.frets.com/HomeShopTech/QuickTricks/DrillBore/drillbore02.jpg

Davidhcnc
08-08-2011, 05:59 PM
Or in a lathe like this is pretty handy.


http://homepage.ntlworld.com/david.hull35/Other%20Images/boring%20tool.jpg

cucvzuz
08-08-2011, 06:09 PM
Thats what I was thinking too

Rather chip $8 inserts on a boring bar then put wear spots in $30 - $40 end mills



Great spot for chinese endmills.

I do only use the insert style bars, on the lathe.

adatesman
08-08-2011, 06:10 PM
Or in a lathe like this is pretty handy.

That it is, and if you've got a stash of chipped carbide endmills lying around they make quick and easy boring bars if there's still a good tooth remaining.

Black_Moons
08-08-2011, 06:47 PM
That it is, and if you've got a stash of chipped carbide endmills lying around they make quick and easy boring bars if there's still a good tooth remaining.

VERY good point, this is a pertty good use for worn/broken endmills, ANYONE can hand resharpen (And grind in relief/clearance) endmills into a decent boring bar, Even if all the teeth are chiped, it would'nt be a huge deal to grind a new tooth.

Can't really hand grind an endmill and expect it to work well as an endmill anymore.

gda
08-08-2011, 07:40 PM
Good use for that new endmill that slipped out of the chuck and broke 1 edge when it hit the corner of the vice.

madokie
08-10-2011, 01:50 AM
i always get my carbide endmills in 2 flute so that when it breaks off cutting teeth,and cant be used for milling , i regrind by hand and make a drill out of it, for removing broken taps and such.works good just go slow,and expect to break off little chunks of carbide getting that broken tap out.

krutch
08-13-2011, 11:59 AM
I have several broken end mills which I have ground clearence to use in my Narex head. I started doing this at the last place I worked, in Peoria, in the '90's. They had some straight flute mills they had gotten cheap and I ground the ends to different forms for jobs and it worked great in the bore-head I rarely throw out mills which I can use in the B head. Even used a mill in the cross hole once, but that tightened the sphincters a little too much for me.


Krutch

jstinem
08-13-2011, 02:04 PM
Broken cutters make good (effective) laxatives. I have more experience with industrial woodworking cutters; Think a 1.5" endmill turning at 20,000 RPM. I know that if break one of those off and send it flying around the shop a lot of S**t will soon follow.

Endmills make good short reamers if if you have one that is right size.

Toolguy
08-13-2011, 09:08 PM
Just remember, endmills used as drills and reamers always cut oversize. You can use that to advantage on occasion, but you must first be aware of it. Sometimes it's a good idea to do a hole in a scrap piece first to find out what size you will end up with.