1.25" hole in 3mm stainless steel plate

[12bolts]

Why is anyone using antifreeze as a machining coolant?

.... a 50/50 mix of antifreeze and water. ...

.... If it contains ethylene glycol it can make you sick....If you must use antifreeze as a coolant please use one that is made with propylene glycol.....

Cheers Phil

 

[JimDawson]

Why is anyone using antifreeze as a machining coolant?



Cheers Phil

It keeps the cutting edge from freezing up :roflmao: Well, somebody had to say it.

 

[Rob. Smith]

I once cut a 2" hole through a 1" thick steel plate . I used a hole saw running at the slowest speed possible and plenty of cutting fluid. The trick was to NOT force the tool and back out and clean the teeth and hole often. It took a while and the hole saw is still good to this day .

 

[Wreck™Wreck]

Now I need to cut a 1.25" round hole in the 3mm SS plate, to install an emergency stop button. I'm pretty sure brute-force drilling with a 1.25" drill bit will not work

Why does drilling not work?

 

[ProMetalShop]

Hi Florin, I would as others have said, use a bi-metal hole saw, ( good quality ) and run slow, with constant feed of cutting oil. Clean the area so the teeth are always cutting new surface. With 1/8th inch stainless you shouldn't have a problem being near the edge where it should be rigid enough with low amount of heat. Even if the hole saw wears a bit you can always go back in and clean it up with a boring head if one is available to you. Please post pictures of your results ! !

 

[chips&more]

A good quality Unibit should work. Run it slow, keep it cutting, do not let it turn without cutting and use lots of cutting oil. They also sell hole saws now with Carbide teeth. That should also do the trick. But might need to be aware of having a ridged set-up so you do not destroy the Carbide…Good Luck, Dave.