asraraleem
Plastic
- Joined
- Jul 8, 2012
- Location
- GERMANTOWN,WI,USA
Hi Guys,
I am used to machining fairly large steel parts but I have never machined plastic (delrin) this big. I need your opinion on how much the part could move after roughing ?. How much stock to leave for finish operations?. And any advice on tooling will be appreciated this is because I need to hold 32 finish.
The part I have is 30 1/2 long 9 1/4 wide and 9 1/16 tall (screen shot and Isometric view of solid model attached).We couldn't find a rectangular stock, so we got a cylinder that is 12" in diameter and 32 1/2 long. All the tolerances are +-.015.
I am planning on having the boring bar rough out the rectangular island leaving 1/4 per side. This will allow me to clamp the part in two 8" vises. I would then rough out the 8.66 X 30.51 (top view) along with the step leaving 1/16 all over. I will then flip the part and rough out the other side, leaving 1/32 on all sides. Then go back and finish top side and later finish the bottom side.
I am a little unsure about the stock to leave for finish. So, Please let me know if I am leaving too much or too little for finish.
The machine I am doing this job is a Kitamura Bridge 6 with a max RPM of 12K. I plan on finish scalloping the angles and some radii using GibbsCAM. But I am not sure if I can accomplish 32 finish when 1/2 bull nose that sticks out 6.5 inches (your advice will be appreciated).
Thanks.
I am used to machining fairly large steel parts but I have never machined plastic (delrin) this big. I need your opinion on how much the part could move after roughing ?. How much stock to leave for finish operations?. And any advice on tooling will be appreciated this is because I need to hold 32 finish.
The part I have is 30 1/2 long 9 1/4 wide and 9 1/16 tall (screen shot and Isometric view of solid model attached).We couldn't find a rectangular stock, so we got a cylinder that is 12" in diameter and 32 1/2 long. All the tolerances are +-.015.
I am planning on having the boring bar rough out the rectangular island leaving 1/4 per side. This will allow me to clamp the part in two 8" vises. I would then rough out the 8.66 X 30.51 (top view) along with the step leaving 1/16 all over. I will then flip the part and rough out the other side, leaving 1/32 on all sides. Then go back and finish top side and later finish the bottom side.
I am a little unsure about the stock to leave for finish. So, Please let me know if I am leaving too much or too little for finish.
The machine I am doing this job is a Kitamura Bridge 6 with a max RPM of 12K. I plan on finish scalloping the angles and some radii using GibbsCAM. But I am not sure if I can accomplish 32 finish when 1/2 bull nose that sticks out 6.5 inches (your advice will be appreciated).
Thanks.