Machinist Apprentice | Stinaless Steel Plate Project | Day 34

Monday back to the grind! Today I worked on getting the steel plate down to its final overall thickness. I absolutely love the look of finished stainless! Its got that nice dark look to it with an almost matt shine.

Since this is stainless steel cold rolled (formed through rollers without heat), it's got a lot of tension built up in it, and so when you release the pressure by shaving one side of the plate down, it will bow ever so slightly in that direction. Because of this I need to remove a thin amount of material from both sides to let it breathe. 

The overall part thickness is about 0.46" (can't give exact dimensions), which is too close to 0.5" to use half-inch stock due to the tension in the material. So my boss bought 0.75" stock and had me shave it down to its final thickness by shaving both sides evenly, starting at 0.05" then as it got closer to the correct height, down to 0.02" stepsons, for better accuracy and to ensure a perfectly flat workpiece.

I had to face the material using a 1/2" endmill, which he explained was to reduce the amount of shock and heat it would generate. If you were to use a larger endmill or flymill your contact would be much higher, thus more friction, and so more heat. The run time for each stepdown was 7 minutes each and had about a quarter-inch to remove, so it took about three hours to do. 

While the machine was running, I got to program the rest of the part. It's got a somewhat unusual shape which can't be held in soft jaws because it needs to be contoured, but does have a few through holes which I'll be using to bolt down to a custom fixture plate for it which I'll go more into tomorrow.