Oval part alignment in vise jaws

[jlembas]

I'm machining oval parts out of aluminum. 3.5 x 11 x .75

The first op has already been done. Now it's time to flip the part over and finish the back side with tapped holes and other details. I want to custom machine vise jaws to fit the profile of the part, but I am worried that it will be difficult to align the part since it is an elongated oval shape.

Will the part self-align correctly? I have included a simple picture for your pleasure. Thanks.

[packrat]

I know you don't want to hear this, but, your doing it backward. the side with the tapped holes should have been done first. Then you bolt the part to a 'tooling plate', a plate with the hole pattern to match the tapped holes. Then you clamp the 'tooling plate' in the vise and finish the part.

cary

[Torsten]

I'm machining oval parts out of aluminum. 3.5 x 11 x .75

The first op has already been done. Now it's time to flip the part over and finish the back side with tapped holes and other details. I want to custom machine vise jaws to fit the profile of the part, but I am worried that it will be difficult to align the part since it is an elongated oval shape.

Will the part self-align correctly? I have included a simple picture for your pleasure. Thanks.

Because of the Parts shape having little length wise constraint I would add a stop to one of the ends to ensure consistent locating.
Other then that it would work just fine.

[jlembas]

Yep...a bit late for a tooling plate. Although I think a tooling plate would probably add too much time to the part loading for what we are doing.

Adding a stop may just do the trick. I will try this tomorrow. Thanks guys.

[fizzissist]

I don't understand why you don't just machine soft jaws to match the contour of the part. Alternatively, take a scrap plate of aluminum and make a matching pocket, with some toe-clamps.

Even with odd shaped pieces, just remember the 3-2-1 clamping guide.

3 points to locate in Z, 2 points to locate in Y, 1 point to locate in X.

(you can exchange X,Y,Z as necessary)

[jlembas]

That's the general idea here. I just not sure if the part will seat perfectly in the jaws everytime due to the large radius. Seems to me the part could possibly be clamped when not completely seated against the jaws.

I didn't get to this today...hopefully wednesday. thanks for the tips.

[christinandavid]

Simple 'V' shaped jaws would urge the component into the correct position and orientation. Radius-on-radius could result in single-point contact.

DP

[jlembas]

I machined jaws to fit the radius and the parts hold great. I also made a stop on one end to locate them. Without the stop, the parts didn't locate without some effort (and time). Thanks for the help.