Drilling/Reaming 304

[Mic6]

Hey Guys. Any suggestions for Drilling and Reaming 304 with cobalt drills and HSS reamers? It's .750 x .188 dia thru. Suggestions as in speeds/feeds. I have 120 holes to do today

[specv]

start off with this:

 

Drill 1072RPM @ 3.2 IPM peck .25

 

Reamer 400RPM @.004 FPT

[Mic6]

I'll give it a shot. thx

[Mic6]

Hmm, holes on size, but there's a bunch of swirly lines in the hole. More feed?

[Josh T™]

EDM Hole Popper! Nuf Said

[Mic6]

HA! Now that was funny

[strabe]

Try a G85 or G86. (Feed in feed out). The swirly lines are prolly from the reamer rapiding out.

 

HTH

[Guest CNC Apps Guy 1]

DEFINITELY feed in/out.

[Mic6]

Oh it has been feeding out, with flood coolant. Maybe my speeds are off. If I look up the speeds in the handbook, they seem superfast.

[chris m]

I wouldn't ream wood with an HSS reamer, but I'd ream 304 with carbide at around 1000 RPM so your speed isn't crazy far off. Feedrate should be .003 or .004 inches per revolution, though, not inches per tooth as was stated in the first response.

 

C

[specv]

I just posted feeds and speeds that we ran thousands

of parts with. But if you are having finish issues you may want to slow the feed down a bit.

[chris m]

Pete, most reamers that size have [6] flutes; are you saying that you are reaming with a 3/16 reamer at .024" per rev?

[specv]

It was actually a .160 reamer but I was running @.015 per rev. .0025 per flute. I was thinking it was a 4 flute. it was 6. sorry

[3R!< W3NG3R]

I hate reamers.

 

We usually bore those holes. A little off topic, sorry.

[chris m]

OK; that's still a lot of feedrate for me [though I don't ream with HSS, which will assuredly take more feed than carbide], but if it works it works.

 

Eric, we ream holes up to around 8mm with great success; I definitely suggest MA Ford solid carbide reamers for anybody not using them.

 

C

[billet programmer]

Ditto on the MA Ford carbide reamers. I use them in lots of stainless alloys - 304,316,Nitronic 50 & 60, etc.

[chris m]

::Hijack::

 

Do you turn a lot of Nitronic 60? Whose inserts do you find to work best?

 

::Hijack off::

 

 

BTW, Pete, you are right; those reamers would be [4] flute, not [6] at that diameter