RFQ: 303 SS parts, CNC lathe job.

We are currently making these parts in house but are looking at subbing them out to someone with the proper machine to run them. Currently the turning work is done in our bar fed CNC lathe, and the flats and hole is done on our Haas mill. Total machining time per piece is about 4.5 minutes, not including load & unload time. It's the load/unload time in the Haas that's killing us mainly due to our crappy fixturing that requires a manual operation. A 4th axis with a hydraulic chuck(s) would go a long way to resolving this.

Before we run out and buy another CNC lathe that has a Y axis, live tooling, and a sub spindle we thought we would see if any one wants to do this at a reasonable price. Most dimensions are not critical and machine tolerance is OK.

Currently we are making these from 3/4'' 303SS round bar, but are thinking about moving to 7075 aluminum. A normal run for us is about 500 pieces of each part, every couple of months.

The attached zip file contains drawings of all 3 parts in several file formats.

Just for context here is a drawing of the assembled parts. Riveted together.

https://www.cnczone.com/forums/attac...d=462308&stc=1

Hi Jim,

You're missing quite a few dimensions on the PDF and DXF drawings, including end radius on .75 Dia., counterbore on .75 Dia. on 1 side of .266 hole, chamfers on .266 holes, radius on .75 Dia. below .266 hole above threads, might be a few more those are just ones coming to mind. Would need all those various dimensions. Also need tolerances on all dimensions as well, +/-.001, .005, .010? And am I quoting out of 303SS or 7075Alum?

Quote:

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Originally Posted by SterlingGear

Hi Jim,

You're missing quite a few dimensions on the PDF and DXF drawings, including end radius on .75 Dia., counterbore on .75 Dia. on 1 side of .266 hole, chamfers on .266 holes, radius on .75 Dia. below .266 hole above threads, might be a few more those are just ones coming to mind. Would need all those various dimensions. Also need tolerances on all dimensions as well, +/-.001, .005, .010? And am I quoting out of 303SS or 7075Alum?

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The IGES or STEP files are the controlling documents, we would normally expect that the G-code would be generated directly from one of those, the pdfs and dxfs are just to show the critical dimensions and are not intended to be working drawings. We can also supply the original F3D file if requested. The counterbore is 0.625 dia, I think we interpolate it with a 3/8 or 1/2 endmill. Chamfers are normal edge breaks, non-critical. 60 to 90 degree countersink could be used. The radius you are asking about is two or three blended radii and I have no idea where the centers are located. All non-specified dimensions are +/- 0.01, there are very few critical dimensions, machine tolerance is close enough for pretty much everything. Once the part is dialed in, I would expect any CNC machine to repeat to +/- 0.0005 or so. The 0.266 hole is just drilled with a 'H' drill, close enough if the drill is sharp. 303ss or 7075al is a good question and we haven't decided yet, you would be safe quoting 303ss. 7075 will require a re-design of one of the parts.

Thank you to all who responded and for your interest in this, and your very competitive quotes. I have to say that your quotes were exactly in line with our estimates, but unfortunately out of our target price range for these parts.


After looking at your quotes and also getting some quotes from local vendors we have realized that our current design is too expensive to build. We are currently redesigning the parts to dramatically reduce the number of operations required by making it entirely a turned profile with a cross drilled hole. Suitable for any lathe with live tooling, no Y axis required.


For now we are going to withdraw the RFQ and will resubmit later once we have a solid design.


Thank you for your time.

Hi will you consider a China machining shop?
Contact me on email [email protected]