Really really silly question...

[gobase]

How do you guys make parts (on solidworks or Rhino or any other) and know exactly where the indents are and the little spaces etc,, so it actually fits into the heli?
For example,, I know the CAD software comes with tools to adjust scale and measurements, and I know you can imagine the piece in your head and draw it on the comp, but how do you actually know that between a corner and an indent on one particular part there is half a millimeter (in many places is very difficult to place a caliper), or more, or less. If you draw the part, and you get the distance to whole for screws or latches wrong then the part wont fit the heli.

Lets say you want to make a part identical to one you already have,, how do you measure the actual part so you know how the lengths, widths, etc will be when you draw on the computer?

Sorry for the super newbie question.

[kmpstr]

You use Calipers and/or Micrometers to measure the part (if you are copying one). There are many other tools and tricks to properly measuring a part.

Once the part is drawn, you can "fit" it into the Heli, assuming you have it drawn in the Computer also. Usually it will involve making a few prototype parts, each a different from the one before, to get to the final design.

Dennis

[RocketSled]

My CNC machine has a probe attachment that can be used to "scan" a part. It "sweeps" the probe across the part, pecking with the probe until it makes contact, then recording the point relative to already-collected points. You end up with a "point cloud" you can then "skin" to recreate the part. I rarely use it for that purpose, though. I use it to locate key spots on the part, outer edges, screw holes, etc. and then use that data to model what I plan to fabricate and make sure the critical dimensions are accurately located.

[gobase]

I read about 3D scanners,, with laser, etc,,, has anybody used one of those for small heli pieces?

[skray775]

That is how I did my first frame.
You can also us a video scanner like this one:
http://www.tormach.com/product_cnc_scanner.html

Originally Posted by kmpstr

You use Calipers and/or Micrometers to measure the part (if you are copying one). There are many other tools and tricks to properly measuring a part.

Once the part is drawn, you can "fit" it into the Heli, assuming you have it drawn in the Computer also. Usually it will involve making a few prototype parts, each a different from the one before, to get to the final design.

Dennis

[celticfc]

Originally Posted by gobase

How do you guys make parts (on solidworks or Rhino or any other) and know exactly where the indents are and the little spaces etc,, so it actually fits into the heli?
For example,, I know the CAD software comes with tools to adjust scale and measurements, and I know you can imagine the piece in your head and draw it on the comp, but how do you actually know that between a corner and an indent on one particular part there is half a millimeter (in many places is very difficult to place a caliper), or more, or less. If you draw the part, and you get the distance to whole for screws or latches wrong then the part wont fit the heli.

Lets say you want to make a part identical to one you already have,, how do you measure the actual part so you know how the lengths, widths, etc will be when you draw on the computer?

Sorry for the super newbie question.

Hand held calipers, micrometer etc and if you are lucky like me a CMM (Co-ordinate measuring machine) accurate to within .0001" but that would be dependent on the part that is actually being measured. Laser scanning equipment which unfortunately I dont have readily available but if need be I can get the use of one. I have just gotten into this hobby and I am looking forward to making my own replacement parts.