C&c cad design for waterjet

[Rsq]

I'll start with the design

Here's a closeup of a yoroi doshi whose dimensions I cant show with the main block

Here is the full block, with dimensions of the three important pieces

So as you can see, I'm making a set of japanese style blades. I have shown the dimensions of the katana, waki, and tanto, including blade width at the habaki and the yokote. The stock will be 36x4x.270/.300 cpm 3v from Jantz, which i will have drop shipped to the waterjet facility.

Here are my questions:

1. The smallest dimension on the cad file is .05 inches. This includes distances between pieces, distance from the edge of the block, and the difference between the blade and the tang at the habaki. Is this too small? Are the tolerances of the blocks or the machines larger than .05? Does a jet cut a larger path that might create interference between patterns?

2. How do my designs look? Are the dimensions good? I wanted to keep them within a reasonable range for a historically accurate set. Obviously a lot of this part will come down to the grind, but just looking at the blanks, what are your thoughts?

3. Does anyone have any idea how much this would cost to get done? I have access to my friends cnc shop, but I don't know if he can get these tolerances, so I'm probably sending them off for waterjet.

My grinds will be fairly similar to Dan Keffeler's, but with slightly more niku right at the edge. I love his work, but I want to make these look a little more traditional (although obviously no hamon).

This is my first time sending things off for work, so I'm looking for c&c on the design. I'm not sure about tolerances for the shops or what instructions I would provide them. Also, what should the finished file be that I send? Is it sufficient to just have a dimensionsed dwg file, or do I need a cad file with machine paths etc.? Ideally I would like all tolerances to be less than .01, is that possible within some reasonable financial constraint?

Edit:

Feel free to comment on or ignore the extra pieces, I just didnt want to waste material, so I threw a few designs in there that might benefit from a thick cpm 3v stock. If you have any ideas for the other wasted metal, I'm open to ideas

 

[P.Brewster]

I'll answer #1 and touch on #3 - a typical waterjet kerf is 0.040". Lets say the kerf is 0.040" and your parts are spaced 0.100". In that 0.100" web, there will be two waterjet passes, thereby leaving only 0.020" of material - almost nothing. There are some shops that can really squeeze parts together but generally I'd leave 0.200" to 0.250" between parts. Then you'll also need to give the shop somewhere to clamp your steel.

If we assume that you come up with a workable layout that won't require lots of set-up time, then I think the market value on waterjet cutting your 6 shapes is probably $150 to $300 (edited - I was thinking 3/16" thick). You generally get what you pay for, but not always. If you're paying for the steel, I suggest you either use a shop that you trust or draft a contract that covers your material in case they screw it up. Very often all you'll get is "oops."

 

[Dan Keffeler]

There is a shop if just started using in Portland OR and I couldn't be happier with their product,communication and turnaround. If you need any help figuring things I would be happy to help where I can.
if you would like you can call me. Most of this stuff is easier for me to explain over the phone.
509 949 2792
Dan

 

[Rsq]

Dan, thanks. That's a really generous offer. I will take you up on that as soon as I'm done with exams. Here's an updated version to reflect the tolerances Brewster recommended. I took out all the pieces but the two big ones, if I have enough stock left over, I'll see what I can do with it. Can anyone c&c this for me?



the closest edge of any cut to any other cut or block corner is .22, the rest are more than .25

This is a screenshot of a dxf file. are there any dimensions I would need to add?

 

[Fellhoelter]

If you are sending DXF to a waterjet, you really only need one dimension, so they can verify scale.

I usually dimension a hole.

I generally leave .1 on the perimeter, and .08 between parts.

What is c&c?

 

[Rsq]

c&c is comments and criticism
exactly like what you just gave, thanks!