Making a curved surface

[Megaplow]

Hello,
I have been completly at a loss on how to machine something that seems relatively simple. Attached is a screenshot of what I am talking about. The object has an extruded shape on the face. The face and the shape both have a curved surface.

Ideally I would like to take away material with a flat endmill then go in with a ball nose mill and deal with the curved surfaces. I have tried all the operations I can in order to accomplish this and keep coming up in the wrong. Can you please point me in the right direction or which operations I should be using?

Regards,
Joe

[Brakeman Bob]

Ideally, this part would be made on a 5 axis machine but not everyone has one of those. So, I would rough it out with ballnose endmill (a) and finish it with ballnose endmill (b).

The size of the part would be helpful in establishing the diameter of the endmill to use.

Use 3D jobs, one for roughing with a surface offset of (say) 0.15 and a second ffor finishing using a Constant Z strategy. If you have the HSM module, use that as it has a really good Adaptive Stepdown facility.

[maparkopo]

I totaly agree with Bob but to make sharp edge ( closely sharp ) at the bottom
use small tool (as small as posible) and do the 3d engraving on the left or right side of the "lifted" part of the shape.For top maybe try HSS ....

[Megaplow]

Eureka!
Thanks for the responses. Unfortunately I don't have access to a 5 axsis machine. If I did, I doubt I would know what to do with it. After spending some time with the solid professor I figured out how to get the 3D milling operations to work. It going to be a two pass cut both with ball nose mills. It looks like it is going to take several hours, but at least I know how to make cured surfaces now.

Happy milling,
Joe

[mattpatt]

Here's a very similar looking part I made for my friend's Yamaha FS1-E 50cc moped.

This is the ignition cover. A curved surface like yours.

I used HSS and HSM on this part. It came out pretty good and is on the bike as we speak. I'll get a pic tomorrow and post it.

Cheers,

Matt.

[Megaplow]

Exactly what I was looking for. Well done! I am going to have to spend some time in the HSS section.

Joe

[mattpatt]

How did you get on with this part?

Just for fun I snapped off a pic of the cover I made. Not a very good shot I'm afraid as the bike's a little jammed in and I just managed to sneak my phone down in there.

Maybe I should've given it a bit of a clean first too

[Megaplow]

Attached is a mistake and an original. I learned a ton on this project. I think next time I will go with thicker stock and all will be well. Your scooter part looks freakin' awesome. Thanks to all for the help.

Well done,
Joe

[mattpatt]

As my old foreman used to say back when I was an apprentice: He who never makes mistakes, never makes anything!

Nothing like throwing a £10,000 gearbox housing off the horizontal mill when you're just a 17 year old lad ;-) That didn't go down too well.