Newbie- Dry Machining, Automation, Better Tools

[Prasham]

Hi,


I have 2 CNC Turning Centers which are used to make bearing type of products from carbon steels. I have some queries regarding:

1) Dry Machining: I've read on few websites about Dry Machining. Leading tool manufacturers like Sandvik, Iscar etc are providing suitable inserts but does it really work better in comparison to Wet Cutting?

This shouldn't bother me much in general but since some time there is some leakage in my old machine which I am unable to repair. If certain grade of inserts can be used without coolant, I think my workshop would be a lot more clean.

2) Automation: Many of you would not believe me when I say that in my town (and almost every town in about 200 kms radii) all the industries are facing labour shortage. Maybe its because rapid development or maybe its because of improved farming practices but every industry is having labour shortage. Hence I am thinking about automating my CNC Turning Centers using some easy (& Cheap) loading / unloading solutions (not the usual robotic arms). I've seen some really impressive videos on youtube and elsewhere but I would love to hear from you guys. Does anyone here use a loading/unloading (or machine feeding or machine tending) solution other than Robotic Arm?

3) I am having more work than I can handle and hence I need better tooling which work faster, longer and are cheap (calculating per piece cost). I like Tageutec's T-Cap system where I can use the same tool for turning ID, OD & Face (it has some limitations like spindle rotation on both sides and proprietary insert design etc). Do you know of anything that can help me out.

I have few more queries but that can wait for a few days.

Thanks

Prasham

[RICHARD ZASTROW]

Prasham, Dry machining usually includes high speeds. High Speed Machining (HSM) requires more than turning off the coolant.

The high work piece and/or tooling usually require balancing.

The machines must be capable of sustained high speeds,(proper bearings etc.) and have the rigidity to keep vibration under control.

Chip guarding must be considered as well. Dry machining doesn't have coolant spray but small, very hot chips require containment.

Many things to consider. LOL

Dick Z

[Shane123]

You might want to look at either doing coolant mist blasting or building yourself a moat around your machine.... lol. I like the moat idea, but not always practical

[Prasham]

Originally Posted by RICHARD ZASTROW Prasham, Dry machining usually includes high speeds. High Speed Machining (HSM) requires more than turning off the coolant. The high work piece and/or tooling usually require balancing. The machines must be capable of sustained high speeds,(proper bearings etc.) and have the rigidity to keep vibration under control. Chip guarding must be considered as well. Dry machining doesn't have coolant spray but small, very hot chips require containment. Many things to consider. LOL Dick Z

Thanks for the reply. When you say high speeds, what kind of speeds you propose? Should it work around 2500 rpm? My Machine's condition is great.

Originally Posted by Shane123 You might want to look at either doing coolant mist blasting or building yourself a moat around your machine.... lol. I like the moat idea, but not always practical

Can you please suggest a supplier of such system. I tried to google but couldn't find anything exciting. ..& BTW loved your idea of building a moat around my machine... My operators would feels like conquering the machine everytime they cross the moat

[RICHARD ZASTROW]

Prasham, Please spend some time studying dry machining and HSM.

The idea or principal behind cutting metal with coolant is to cool and lubricate the tool and the metal (chip) being cut to prevent the chip from welding to the cutting tool.

In dry cutting the idea, or principal, is to have the cutting surface speed high enough to carry the heat that is generated in the process off with the chip. When proper feeds and speeds are employed in dry cutting, the workpiece will remain at ambient temperature and the chips will carry off the heat.

The cutting tool and machine must be capable of both generating and absorbing the forces employed.

Dick Z

[Shane123]

here is a kool mist..... its mainly a air blast with a little bit of coolant to add lubricity. Spray Mist Coolant Systems, Mill Coolant, Tool Coolant, Lathe Coolant, Machining Coolant by Kool Mist

[Shane123]

after looking at the setup on koolmist website, you could probably build your own with a gerbil watering bottle (or rabbit watering bottle), an air hose always on aimed at the part but must cross the tip of the watering bottle, and a fixture to hold the hose and bottle.

The advantage is not having to run dry and using a very minimum of coolant instead of flooding so less likely to get a leak.

Its either mist the part, use air blast alone, machine dry, or track down the leak. Or build a moat, lol. Trust me, i have tossed the idea of building a moat on our tree vmc, its very finicky on keeping the conveyor trays clean of fine swarf, if not it tends to leak.

[RICHARD ZASTROW]

Speed will depend on the diameter of the workpiece or tool, the material being machined and the cutting tool material. Also, if the cutting tool has a coating, what is the coating?

TiN, TiAN, SiCN, or ????

Some coatings do not survive in dry machining, others fail if coolants are applied during high speed machining. This has something to do with the high heat generated at the workpiece/tool interface causing a chemical reaction.

You may have to experiment to find a combination that works for you. The coolant/mist supplier should be able to assist with that.

Dick Z