process insight using indexable drill

Good evening,

Long time browser/keyword searcher, first time poster here. I am always amazed with the amount of wisdom and knowledge I am able dig up within. Just a little background - I manage a family owned and operated machine shop which has been in business since 1996 here in Texas. We primarily provide service to oil and gas service companies (along with your occasional lawn mower blade sharpening ). If any of the following is not allowed or frowned upon please let me know and I will remove.

I have a part that is a tube with a flat bottom bore (at least that is what I saw when I quoted it). Sketch attached to make it easier to see what I'm dealing with. We have had issues across the board with this thing. It started with tooling then work holding, now its ether back to tooling or a combination of tooling and process. The main issue now is getting and maintaining the 63 finish in a realistic way.

We are drilling a 3” deep pilot hole with a 5xD Sumocham drill, then going in with a 12xD Sumocham drill to approx. 8.3” depth. Both drills use the same ICP 194 head. After the 12xD, we finish with a long .75” FB spade to depth. The part is being ran on a Mori Seiki NTX2000 with 900psi thru coolant and takes around 5 min to complete the cycles. Speeds and feeds obtained from ISCAR.

The 12xD bore looks and feels to be around 63 finish (our profilometer will only reach in about 2”). The 5xD bore is the ugly one. It looks maybe a 63 before going in with the 12xD but after the 12xD retracts, it has definitely been affected. All features check good dimensionally. Drill bodies are basically brand new - used a couple times. Drill heads are brand new. I’ve seen these tools produce amazing results so I do not want to waste time with reamers, burnishing or honing.

Anyone ever run into similar issues? Could the pilot hole be incorrect or unnecessary? Any comments, insight or tips would be much appreciated!!

Links to tools:
https://www.iscar.com/eCatalog/item.aspx?cat=5509266&fnum=2672&mapp=DR&app=0&GFSTYP=M&isoD=1
https://www.iscar.com/eCatalog/item.aspx?cat=3202835&fnum=3148&mapp=DR&app=77&GFSTYP=I&isoD=1
https://www.iscar.com/eCatalog/item.aspx?cat=3202646&fnum=2670&mapp=DR&app=77&GFSTYP=I&isoD=1



-Jordan

Check out this head, the QCP-2M : https://www.iscar.com/eCatalog/Fami...=I&rcat=3202646&item2=&ssOrder=&loc=&IC=&Pos=

It is relatively new to the market but it's self-centering like the HCP and double margin to give a better hole finish. You should be able to drill to depth using the 12xD drill with no pre-hole or spotting.

I don't know what speeds and feeds you're running (4140 PH, right?) but I would start at 250 SFM and .01 IPR. Bump up the feed to break chips if necessary. At least your material isn't gummy...

Another tip....to improve hole finish, stop the spindle before retracting. This will reduce the swirl marks on the sides.


And you're right, the SumoCham is a great drill!

I bet the drills aren’t drilling perfectly on center so the second one is scraping the walls of the first one on its way in/out. Can you call up the second tool to X0.0 and hand jog it into the material to see if you can see the drill flex at all? Maybe try drilling the entire thing with the 12X drill? Good luck!

jd0925 said:

We are drilling a 3” deep pilot hole with a 5xD Sumocham drill, then going in with a 12xD Sumocham drill to approx. 8.3” depth.

Click to expand...

In my experience with drilling deep holes, your pilot is too deep.

With the QCP-2M drill head he can drill 12xD just fine with NO pilot, just sayin'..........

Problem should be solved but OP has gone AWOL so we'll never know.