Need some Suggestions on Creating a tool path

[jjp24]

i need to create the tool path circled in red and have no idea as to how to create it or what to use. it also tapers from the cutting depth of about -.25" at the bottom to zero at the top.

thanks in advance for any help and suggestions.

[IMG][/IMG]

[steve_g]

Roger...
Other than a true 3d machining, we'll be approximating I think. Is the cross section a section of a circle? What I'm hoping you can do in 2d is do a taper or even a "v-carve" with a ball nose bit.

SG

[jjp24]

hi steve

yes, the cross section is circled at the bottom. thanks for the response.

[dana_swift]

Since it is a 0.25 taper over what looks like a long distance, how about slide a quarter inch shim under the end that should be 0.25 deep, then cut a pocket at "zero" depth. As the material rises.. it will get cut on a taper.

Precision may be difficult to obtain, but close should be easy that way.

Use a ball nose bit to make the round shape. Is it from a pinball machine anybody would be familiar with?

D

[steve_g]

Dana's method is the easiest if you can hold it reliably... it will however require you to cut that one feature in a separate fixtureing. Using a "v-carve strategy with a ballnose bit of the same diameter of the semi circle will let you cut it in one fixtureing but the radius of the narrower portion will be a section of the larger radius and not a semi circle. Clear as mud?

SG

[steve_g]

I thought I'd add a picture of what I was trying to say...

SG

[jjp24]

this is for a prototype whitewood playfield.

it's about 14" long and .98" at the widest point. i would think it would be a rather costly bit

[jjp24]

I thought I'd add a picture of what I was trying to say...

SG

that is for sure what i'm looking to do!

[steve_g]

An arc .98" wide and .25" deep is a section of a 1.2104" circle... would a 1.25 ball bit be close enough?

SG

http://www.magnate.net/index.cfm?event=showProductGroup&theID=224

$ 31.80 ... not too bad!

[jjp24]

i think that will do it!!
thanks for the link and the help.
i will try to remember posts the results