2 attached pdfs show a difficult part that I've been trying to make. "Process 1" shows the blank, "Process 2" shows the desired part.
I had a few of these blanchard ground. They hit the dimensional tolerances, but not the straightness/flatness. They were flat to 0.003 or 0.004. I imagine that the magnetic base held the part flat.
I got a quote from somebody who was sure he could nail the tolerances. He said he would grind down to 1.420 x 1.420, then stress-relieve, then finish the grind. But he wants $600 for 2 parts.
I can't pay $300 per part. I would like to pay no more than half that.
I could supply a stress-relieved blank that is 1.420 x 1.420 ±0.005 if anyone thinks they could finish the job for $50 or $75.
I would also be willing to make sacrifices if necessary to bring the price down:
1) change the 1.400±0.001 to 1.400±0.002
2) change the Flat and Perpendicular tolerances from 0.001 to 0.002
Also, I may fab the blank from 1/4" plates, with 4 welds rather than the square tubing if we think that will make a more stable blank.
Please note that this will not be a fast cash job. I'm playing around with the out-of-spec blanks I already have, and I won't need more for about 2 months.
thank you
I had a few of these blanchard ground. They hit the dimensional tolerances, but not the straightness/flatness. They were flat to 0.003 or 0.004. I imagine that the magnetic base held the part flat.
I got a quote from somebody who was sure he could nail the tolerances. He said he would grind down to 1.420 x 1.420, then stress-relieve, then finish the grind. But he wants $600 for 2 parts.
I can't pay $300 per part. I would like to pay no more than half that.
I could supply a stress-relieved blank that is 1.420 x 1.420 ±0.005 if anyone thinks they could finish the job for $50 or $75.
I would also be willing to make sacrifices if necessary to bring the price down:
1) change the 1.400±0.001 to 1.400±0.002
2) change the Flat and Perpendicular tolerances from 0.001 to 0.002
Also, I may fab the blank from 1/4" plates, with 4 welds rather than the square tubing if we think that will make a more stable blank.
Please note that this will not be a fast cash job. I'm playing around with the out-of-spec blanks I already have, and I won't need more for about 2 months.
thank you