3d machining (propellers)

[cabnet636]

one of my fellow machine owners and i are try ing to find if any one has machined ultralight propellers with a three axis machine.

any input would be appreciated

jim

[Fiddlemaker5224]

HT at go3d.com has a prop design for the carvewright machine. It was instresting to see it devloped on the carvewright software. I haven't tried that carve, no need really. But the prop looks good, I would check there and it may give you some ideas. I do know that it requires a two sided carve. I bought a violin plat model from him a month ago and have carved 8 plates for them with little modifaction.

[Big S]

I have just been thinking about this as I was lined up to start a job making propellers for ultralight aircraft, Then along came my CNC . I think it is quite do-able and should be faster than a copy carver. All the mounting holes can be done at the same time.

Shannon.

[TOTALLYRC]

I have just been thinking about this as I was lined up to start a job making propellers for ultralight aircraft, Then along came my CNC . I think it is quite do-able and should be faster than a copy carver. All the mounting holes can be done at the same time.

Shannon.

Should be eay to do, all you need is a master to probe and voilia, you have code. Add in the bolt holes and you have a prop. I would look at holding the blank between centers of your 4th axis and being able to do the whole prop in one sitting. You would have to clean up the ends after it was finished but it should be faster overall than turning the prop over.I think it would allow you to twek the thickness and other things fairly easily.

Mike

[Big S]

I only have a 3 axis CNC , would do it in two sides with a ball nose cutter. I am cosidering leaving some of the timber on the ends of the prop for support as the tips sometimes are only 5-7mm thick (around 1/4")

There is a video somewhere of a 5 axis machine making wooden propellers and they had two jigs side by side and once one side was done they flip the prop into the second jig.
I think it was on you tube but I can't seem to find it.

Shannon.

[TOTALLYRC]

I only have a 3 axis CNC , would do it in two sides with a ball nose cutter. I am cosidering leaving some of the timber on the ends of the prop for support as the tips sometimes are only 5-7mm thick (around 1/4")

There is a video somewhere of a 5 axis machine making wooden propellers and they had two jigs side by side and once one side was done they flip the prop into the second jig.
I think it was on you tube but I can't seem to find it.

Shannon.

You can of course do it on a three axis machine. you should be able to cut most of the prop from one side including the hub and then use a gig aligned with the bolt holes to make sure it is dead on when you flip it over.

a set of machinist jacks or purpose made blocks to support the ends when machining on the second side would work out well.

I will keep watching your progress.

Mike

[Big S]

The video I saw had a block cut out to suit the first shape that was CNC cut so the when the half cut prop was flipped over it fitted snugly into it. This would be good for props that get more than one or two made but for custom props the jacks could be the way to go.

Shannon.

[TOTALLYRC]

The video I saw had a block cut out to suit the first shape that was CNC cut so the when the half cut prop was flipped over it fitted snugly into it. This would be good for props that get more than one or two made but for custom props the jacks could be the way to go.

Shannon.

I like the idea of a fitted support for the underside. Great for a long run of identical parts. Sort of how a wire cut foam wing uses the bed it was cut from for support when vacuum forming.
Mike

[Big S]

Foam could also be used for the bed if only one or two props were being cut

Shannon.

[cabnet636]

we have an stl file of the propellor, it's cutting it with cut 3d that is the problem. it will machine one side then when it is fllipped it can't machine where it thinks material has been removed or is not there.

i'll get tom here

jim

[Big S]

Jim,

Have you tried setting up an entirely new file, to do the other side, with identical offsets and material size to the original of course.

Shannon.

[cabnet636]

wow good idea! i emailed tom to get to this forum do you have cut 3d?

jim