.008" Slitting Saw-Student needs help!

[Dan from Oakland]

I've made hundreds of very similar tiny channel heat exchangers for scientific instruments in a previous job/life. These were .008" wide channels, .030 deep and 6" long in 6061, so it is very doable. 1st off, call Robjack and buy some quality carbide saws- HSS will just drive you crazy. Robjack is close to you up in Lincoln. Robjack should be able to give you feed/speed starting conditions, but be aware, they can be kinda agressive cuz they are proud of their tools. 2nd- buy a precision saw arbor and indicate it true when you mount it. This is critical to keep the tooth load in the saw teeth uniform. Using a junk import arbor will only lead to broken saws. We still broke saws on occasion- it was just part of the job.

Based on my experience you will have a hard time being successful with HSS saws and running this on a manual mill is going to be a challenge because of the fragile nature of the saws. I'm not sure I would even consider an end mill- you don't have anywhere near the spindle speed to run a tool that small.

The carbide saw is much stiffer and will not wander down the length of the slot. Keep your chip load very light- .0005/.001 per tooth. This might be an issue for you on a manual machine. I would suggest kerosene or mineral spirits for coolant. Best of luck!! please report back.

 

[eKretz]

Carbide saw for sure.. Also make sure you don't have a lot of stickout of the blade past the arbor. Keep that minimized - make "stabilizers" or stiffeners of the correct diameter to support the saw if you need to. Those help immensely with thin slitting saws.

 

[Peter Colman]

I would try a stack of slitting saws with spacers between them and do the job in one cut ie horizontal milling.
coolant lubricant is vital to keep the job cool and stop the chips sticking to the tool.