Drilling SS question.

[Blue Crab]

I saw it but this is the INTERNET.

[delmarrey]

Originally Posted by Cotemar

Sweet square hole drill.
I used to be a machinist and have never had a need for that, but must be a need somewhere. We used to use a broach for square slots.

When you have a blind hole, then a broach will not work. I've used broaches for making internal planetary gears. It sure speeds up production.

Now here's some extreme machining. These chips are coming off red hot. But they're using a special carbide tool.

Notice the water lines. Those are for when using HSS/cobalt cutters. Carbide cutters will crack if you use coolant.

RobbJack High Speed Hard Metal Trochoidal Machining 54 HRc Hardened H13 - YouTube

[delmarrey]

FYI

If one has a couple hundred $ to spare and a compressor available, this is the preferred cooling system out there that Machinist's worldwide use for general purpose cooling for drilling and milling, even some lathe work. On table saws it can be added for cutting aluminum plate.


Kool Mist - Kool Mist General Purpose Models with Stainless Tank

[Cotemar]

Trochoidal Machining makes sense as it’s not a full plunge cut. No chatter, less force and better surface finish
Much less chip load and the heat is in the chips not the part.
Nice

[Anonymous7500]

Originally Posted by delmarrey

Now here's some extreme machining. These chips are coming off red hot. But they're using a special carbide tool.

Notice the water lines. Those are for when using HSS/cobalt cutters. Carbide cutters will crack if you use coolant.

I am going to respectfully disagree, but just a little. The main reason for using high pressure air in this situation is to keep from re-cutting the chips. Re-cutting chips will cause very premature tool failure. The high pressure air is more effective at removing the chips than a coolant flood.

If a carbide end mill is being used properly, the heat will all be put into the chips. The tooling should only have heat at the cutting edge. The work piece should remain cool. New(er) CNC mills are capable of pumping very high volumes of coolant. These high volumes prevent the carbide fracturing that used to be a problem. We flood all of our machining operations in our enclosed machining centers.

Something else that may be interesting is that carbide drills have coolant holes running through them that are fed with very high pressure coolant through the spindle. Pressures can exceed 1,500 psi depending on the pumps in the machine. We are able to drill through 2" of tool steel without "pecking" the drill with a .437" drill spinning about 1,800 rpm at 25+ inches per minute.

[Wotname]

Hey Blue Crab, wanna have a beer while the machinists finish off here

[Blue Crab]

Originally Posted by Wotname

Hey Blue Crab, wanna have a beer while the machinists finish off here

Yes sir! I'm buyin!

[Cotemar]

Originally Posted by Wotname

Hey Blue Crab, wanna have a beer while the machinists finish off here

I am not a machinest anymore. Lets go for that beer

[delmarrey]

Originally Posted by Anonymous7500

I am going to respectfully disagree, but just a little. The main reason for using high pressure air in this situation is to keep from re-cutting the chips. Re-cutting chips will cause very premature tool failure. The high pressure air is more effective at removing the chips than a coolant flood.

If a carbide end mill is being used properly, the heat will all be put into the chips. The tooling should only have heat at the cutting edge. The work piece should remain cool. New(er) CNC mills are capable of pumping very high volumes of coolant. These high volumes prevent the carbide fracturing that used to be a problem. We flood all of our machining operations in our enclosed machining centers.

Something else that may be interesting is that carbide drills have coolant holes running through them that are fed with very high pressure coolant through the spindle. Pressures can exceed 1,500 psi depending on the pumps in the machine. We are able to drill through 2" of tool steel without "pecking" the drill with a .437" drill spinning about 1,800 rpm at 25+ inches per minute.

Your probably right, as for the video. I'm just trying to keep it simple for the laymen here. If we get to deep they'll run out of air. Many times I've just used an air nozzle when doing small end mill work.

Originally Posted by Wotname

Hey Blue Crab, wanna have a beer while the machinists finish off here

What about us? We're doing the educating.

[Blue Crab]

Originally Posted by delmarrey

What about us? We're doing the educating.

Yep, yep and yep. It really would be great to meet everyone.

[bobconnie]

I don't drink beer, but will drink something, and enjoy the BS LOL

[Wotname]

And get to meet a few hard-core machinists (and ex ones) and the general riff raff (like me )

[Hoohaa]

Job Done..
Drilled the bow roller at home on the drill press, pilot holes and then a 10mm bit. before you ask, I got the bits given to me by my freinds son who manages a machine shop. I will find out what they were and let you know. I did buy a cobult and 2 other bits which I never used.
Here are some pics.
Stage 1



Stage 2
Used this really good cordless drill with no pilot holes and a mistery cutting fluid that I will post the name of as soon as I find out.






Can't wait to install the new Anchor.
Thanks for all the great tips, I think Its time I had a bear.

[DeepFrz]

Congratulations for digging your way through all the confusion and just getting it done.

[Cotemar]

Nice job. We are so glad you did not listen to us