Partial thread MC9

[Flycut]

I've tried this in the past but have never been successful.

I put a file on the FTP site in the MC9 folder called Mazda3 cap.

All I want to do is draw a spline(thread), that starts at Point 1 Z0-.310 and ends at Z-0.47 on a 1.120 minor OD.

I'm sure there's about a dozen ways to do this and I can't even figure one out.

 

 

 

Thanks guys.

[JDowe]

Draw the arc at z-.310

Then break the arc in pieces - say 4

then divide the total z depth differenc by 4

(.470 - .310) = .160

then (.160 /4) =.04

Create a point on the end of the arc by setting

z at -.310

then the next point at Z -.040 more etc. so you have 4 points at the different depths

then create a spline through the points

Set c- plane to 3-d when creating the spline

If you need more accuracy use more points

[Ocean Lacky™]

Just curious.....would it not be better to use 3 points and use a 3point arc? I think a 4 point spline (depending on the diameter) would yield a slightly squared shape.

[JDowe]

Reconsidering I think if you create points

on the end of the arc at z-.310

at the midpoint of the arc at -.390

and the end at -.470

and set c-plane at 3-d

you can create an arc through 3 points

[JDowe]

oops

[Flycut]

That works well.

Thanks.

[crazy^millman]

You could also use Ramp Toolpath ,but would need to do a little work. I would draw the Thread out then cut out the parts of the thread I did not want. Then you know how much distance you are ramping for that thread. Then you would make that the ramp depth. Then if you were doing 10 threads and it was a 16 thread then do a depth of cut and not use the Depth option use the finish option. Number of cuts 10 the finish amount of .0625. Now you would get 10 cuts where you could control lead in and out for each pass of the thread with also the ability to multi-pass. Now all the math is handled inside the post and you are not relying on some function spline to make the toolpath correct. I would make an arc at the top of the thread to cover that same distance you would be cutting with the ramp gives you more control.

 

Another way to do this is draw a helix and then cut out the section you do not want. Then use #d contour in the contour options and then increment the top of stock and depth to Zero. Then pick the 10 chains and would do the same thing if you could get the helix to break up right. You also have the multi-pass in this method as well.

 

HTH

[Flycut]

Thanks for the help guys.

That was for the underside of my oil cap.

Now I'd like to do the top.

I want a 3D surface of the Mazda logo to go on top.

I've got a 2D outline of it now that I converted using Wintopo then cleaned it up and tried to keep at as few splines as possible.

 

 

I have a file on the FTP site called Mazda3 for this thing.

What I would like to do now is create a surface that goes from the blue contour to the red center in a "pyramid" fashion.

Any help would be great.

I don't even know what surface creation type to use.

[Kannon]

on the ftp under version 9...

check Mazda3kannon.mc9 and tell me if thats what you want.

[Zero]

I would translate the red center geometry up in the z and then create ruled surfaces between the blue and red geometry to get your pyramid shape surfaces. This can get a little tricky depending on how the chains are broken up.... I dont have MC here at home, but if you can upload an igs file of this geometry to the ftp, I could do this for you in rhino pretty quickly if you want

 

[ 01-17-2008, 09:54 AM: Message edited by: Zero ]

[Zero]

..oops, double post

[Flycut]

I see a MAZDA3 CAPKANNON.MC9 file there wich is the help you gave me for the threaded side.

But I don't see a Mazda3kannon.mc9 file.

In the MC9 folder?

[Kannon]

I have it so level 1 is a solid and level 2 is surfaces..

[Kannon]

go back in there again...should be right below Mazda3 in the mc9 folder.

MAZDA3KANNON.MC9

[Dan@home]

Flycut Like this..

 

It will be under DANS_MAZDA3

[Kannon]

I just emailed it to ya...

[Flycut]

Thanks Kannon.

Still don't see it in the MC9 folder.

That's exactly it Daniel, what method did you use?

[Kannon]

Someone else want to check the ftp...see if its in there...

 

I see it.

[John13]

It's there,

[Zero]

I see MAZDA3 CAPKANNON.MC9 as wel...

[Dan@home]

Sweep Surfaces, Had to draw lines on sharp connecting edges. On top U shape had to do net surface to point on ends of the U. Those were a little tougher.

 

Daniel.

[Flycut]

About the FTP site giving me trouble, I had to "open FTP site in WIndows Explorer" then enter the password to find the missing files.

Got them now ty.

[Dan@home]

Is this for your own car?

[Flycut]

This one yes.

 

I'm making a few others that will have different tops.

One will have a skull and a few others will be black anodized with some engraving threw the anodize.

I think I could get into trouble if I tried to sell something with someone else's logo on it.

[Flycut]

Thanks for all the help guys.

Here's what I came up with.