[ormandj]

Well, I've already posted in the mentor/tutor area, hopefully I'll get a taker on helping me learn/get experience on real machinery. That's one half of the equation. As for #2 -

I'm interested in starting to churn out my own R/C helicopter parts. I'm tired of seeing really bad designs and seeing thousands of posts with complaints (and easily created improvements) - and nobody filling the void.

I'd like to start making them myself. I've got basic abilities in AutoCad from years ago, and I'm going to start learning Rhino (it's been suggested this is best for doing 3d design, which I think is necessary in the CNC world for the type of parts I'll be making.)

The real question boils down to what kind of machine I'll need to work with. My lack of experience with this kind of equipment has me lost. Here's a couple of typical parts that would be nice to be able to make (or change/improve..):

http://www.align.com.tw/shop/product...oducts_id=1016
http://www.align.com.tw/shop/product...oducts_id=1010
http://www.align.com.tw/shop/product...oducts_id=1011
http://www.align.com.tw/shop/product...oducts_id=1007
http://www.align.com.tw/shop/product...oducts_id=1354

Just a few examples, basically a lot of aluminum parts (with steel being an option would be *nice* but not necessary..)

I've been told by people who really don't have much experience that a 4-axis mill is what I'd be looking at, especially if I wanted to do CNC eventually (I do..)

Does this sound correct? Am I barking up the right tree? It'd be nice to be able to use the machine to also cut out frames (CF mostly) and various other parts like that too. Maybe Delrin, various plastics, etc.

If you could give me any direction, it would be very much appreciated. I just need an idea of *what* to start researching, so I can learn more. It's hard right now because I don't even know what to search for. Also, hopefully somebody will take me in and help me learn, I'm offering to pay material expenses and do work (in my free time) for whoever is willing to help me learn. Hopefully somebody in Hawaii will bite!

Cheers,
David

[JerryFlyGuy]

I certainly don't have all the answers to your questions. After looking at some of the parts you've linked to, however, I'm of the opinion that most if not all the parts your going to want to make will need cnc equipment. Most heli parts [at least the heli's I've worked on and flown] are relatively small in size. Therefore huge machining equipment shouldn't be required.

I would think that a 4 axis system at the least would be needed. If you do go to a 4 axis system, it will have to be cnc, there isn't really any options there. I would say that most of these parts would be best served by using cnc equipment. There isn't any that I saw on your list that would be easily done w/out it [ at least they could never look as nice w/out cnc]

I think your best option would be a cnc lathe w/ a 3 axis mill attachment and a positionable 'C' axis [ the lathe axis that turns]. Also investing in some casting of alum parts would make some of your projects much simpler, you'd only have to finish machine them instead of cutting them from a ruff billet.

Also worth mentioning is that your going to have to be very efficent if you want to compete w/ the listed prices on that website. For example, the last link show's a tail rotor blade holder w/ pitch links. This is made from 3 basic parts, two of which are identical. Each of the blade holders would need at least the following setups.
1) Turning to the proper O.D.
2) Turning the bearing housing parts and making sure to get the proper fits.[two setups due to the orientation of the bearings]
3) Finish milling of the 'Arm'.
4) Drilling the center hole.
5) Drilling the blade mount hole and tapping it.
6) Milling the blade grip's [or whatever the proper term is.. where the blade sits in.. that milled slot]
7) Finish milling the end face [ so its round like the one shown]
8) Drilling and tapping the Linkage ball mount hole.

[that might not be all in the proper order either..]

This would need to be done twice.

Then you need to make the center housing, which would have 4 bearing fits and two drilled and tapped holes for mounting the blade grip housings.

Finally the whole assembly should be assembled and balanced..

Thats all fine and dandy.. but to do it all for $20... thats a tall order..
Even if your time is only worth $5/hr.. and the mat'l was free.. I think it'd be tough to break even.

I'm not trying to discourage you from going ahead w/ this, just to shed some realistic light on what it's going to take. Over time you may get all these process's down so they are all automatic via Cnc, but doing it manually would be a nightmare.. if its possible at all. Going the cnc route, you might get it down to where 1 of these blade grip's is getting cut faster than you can assemble the completed unit. The only way to find out is give it a try .

Hope that helps in some way..

Jerry

[ormandj]

I certainly don't have all the answers to your questions. After looking at some of the parts you've linked to, however, I'm of the opinion that most if not all the parts your going to want to make will need cnc equipment. Most heli parts [at least the heli's I've worked on and flown] are relatively small in size. Therefore huge machining equipment shouldn't be required.

Yeah, most of the stuff is really tiny. I also agree, to make stuff this small perfectly, I'm SURE will require CNC.

I would think that a 4 axis system at the least would be needed. If you do go to a 4 axis system, it will have to be cnc, there isn't really any options there. I would say that most of these parts would be best served by using cnc equipment. There isn't any that I saw on your list that would be easily done w/out it [ at least they could never look as nice w/out cnc]

Ok. Thanks.

I think your best option would be a cnc lathe w/ a 3 axis mill attachment and a positionable 'C' axis [ the lathe axis that turns]. Also investing in some casting of alum parts would make some of your projects much simpler, you'd only have to finish machine them instead of cutting them from a ruff billet.

Ok. I'll have to lookup these things, but now I've got a starting point! I really appreciate it.

Also worth mentioning is that your going to have to be very efficent if you want to compete w/ the listed prices on that website.

I don't want to compete with them. Those parts are made in Taiwan, there is no competition possiblity in terms of price for me. I'm planning to compete with quality/design. (Of course, with higher price tags..).

For example, the last link show's a tail rotor blade holder w/ pitch links. This is made from 3 basic parts, two of which are identical. Each of the blade holders would need at least the following setups.
1) Turning to the proper O.D.
2) Turning the bearing housing parts and making sure to get the proper fits.[two setups due to the orientation of the bearings]
3) Finish milling of the 'Arm'.
4) Drilling the center hole.
5) Drilling the blade mount hole and tapping it.
6) Milling the blade grip's [or whatever the proper term is.. where the blade sits in.. that milled slot]
7) Finish milling the end face [ so its round like the one shown]
8) Drilling and tapping the Linkage ball mount hole.

[that might not be all in the proper order either..]

This would need to be done twice.

Then you need to make the center housing, which would have 4 bearing fits and two drilled and tapped holes for mounting the blade grip housings.

Finally the whole assembly should be assembled and balanced..

Thats all fine and dandy.. but to do it all for $20... thats a tall order..
Even if your time is only worth $5/hr.. and the mat'l was free.. I think it'd be tough to break even.

From what you just described, I'm positive you are correct! I'd just do it for $50-100 instead.

I'm not trying to discourage you from going ahead w/ this, just to shed some realistic light on what it's going to take. Over time you may get all these process's down so they are all automatic via Cnc, but doing it manually would be a nightmare.. if its possible at all. Going the cnc route, you might get it down to where 1 of these blade grip's is getting cut faster than you can assemble the completed unit. The only way to find out is give it a try .

Hope that helps in some way..

Jerry

I really appreciate it, especially the honesty and realistic viewpoint. It's exactly what I was looking for! I do intend to automate everything via CNC, I just plan to try and find somebody with a manual lathe/mill and learn the basics that way, so when I'm doing the CNC stuff I understand the mechanics as well as the software. I don't want to invest a gazillion dollars in equipment if I'm just not going to be any good at it. Hopefully I can find somebody around here who will let me volunteer at their shop in exchange for a guiding hand!

Cheers,
David

[Edit: Forgot a question...]

JerryFlyGuy, might you be able to point me to a link or something to a machine like the one you described? Would it be called a "four axis lathe"? One axis being the lathe turning, then 3 being the milling portion? I'm trying to figure out how it would make something like the blade grips which are hollow on the inside, if they are mounted on the lathe at both ends. My ignorance showing..

[daedalus]

If your planning on selling these what kind of quantity are you looking at? what i mean is you may be better off using your tools to prototype designs, then finding someone to manufacture them in quantity for you. If you want to be making lots of these quickly you are going to need some expensive kit, if your making the odd prototype then you can get by with much cheaper equiptment.

It all depends on how many you need to make and how quickly you need to do it i guess.

[ormandj]

deadalus: They are likely lower quantity/higher price type parts. IE. they need to be *perfect*, but I don't need to make a ton of them. I would guess maybe 5-10 parts a day at MOST. If I were selling that many, money to buy a 100k machine wouldn't be an issue. Most likely no more than a part a day, maybe less to begin with. I'd use it to prototype/etc too, of course.

[InspirationTool]

I'm in the "fill a need in a hobby you know" business.

Here's my thoughts:

You are going to have to learn 3D cad, and get pretty good at it.

After you make a 3D model, you can make it yourself, or outsoruce it.

If you want to make it yourself, that means learning another (and I suspect harder) skill and spending at least somewhere between $4-$8 K. (either the X3 with a rotary table or the Tormach with a rotary table) These will NOT be as cabable as a larger $40 K to $400 K VMC that a pro would use, but would get you started.

It comes down to do you have the time and money to learn 4 axis machining, and does that sound fun? Or would you rather have parts in your hands to sell?

Personally, I'd start with the outsourcing. If it goes well, bring the operation in house.

-Jeff

[ormandj]

I'm in the "fill a need in a hobby you know" business.

Here's my thoughts:

You are going to have to learn 3D cad, and get pretty good at it.

After you make a 3D model, you can make it yourself, or outsoruce it.

If you want to make it yourself, that means learning another (and I suspect harder) skill and spending at least somewhere between $4-$8 K. (either the X3 with a rotary table or the Tormach with a rotary table) These will NOT be as cabable as a larger $40 K to $400 K VMC that a pro would use, but would get you started.

It comes down to do you have the time and money to learn 4 axis machining, and does that sound fun? Or would you rather have parts in your hands to sell?

Personally, I'd start with the outsourcing. If it goes well, bring the operation in house.

-Jeff

That's an excellent plan. I've already had a couple people PM me interested in producing the parts once I got the CAD work done. I can start that way, without the upfront cost of equipment, and worst case I'll be out some time and the cost of the CAD program (which I can use for many things regardless!)

What's the best 3d cad program going now? I've heard lots of great things about Rhino, but I don't want to plop down 1k on software and find out I made a mistake, because I don't know what I'm getting into. :P I tried autocad 2007, 2d seemed the same as the version i used way back when - except WORSE. 3d was almost unusable.

[InspirationTool]

The "which 3D cad" question has been hashed around ALOT on this board, do some searching. I'm not at the point where I will buy a 3D cad program, but I've done some looking.

Definately look at Rhino. I found it very easy to use from an AutoCAD background.

Frankly though, I think I will regret it if I don't get a parametric system. For me, that means Alibre.

-Jeff

[JerryFlyGuy]

Or SolidWorks..

Jerry [Sorry Jeff.. I just couldn't resist ]

[ormandj]

You guys are killing me. :P :P (Thanks!)

I checked out Alibre's site (I'll download the free version tonight) it looks REALLY nice. Does it allow me to export in a format that most CNC guys can use? IE if I don't own my own CNC mill yet, could I export into a format they could read using their software?

Also - if I do end up getting my own CNC equipment, and I want to do 4 axis (or even 5), is there something that will take Alibre models and run the CNC stuff from it? On their site, even with the most expensive version, the software tops out at 3.5d CNC.

Solidworks is out of my initial budget I think, there isn't even pricing on their site. About how much would it run me?

[InspirationTool]

Or SolidWorks..

Jerry [Sorry Jeff.. I just couldn't resist ]

Jerry... I would *LOVE* to have solidworks, but I got a quote for the cost and plotzed.

-Jeff

[JerryFlyGuy]

I hear ya, but in reality.. if a person was planning to buy a 100k machine for making the parts.. I'd be taking the leap ASAP.. I drive it all day long and now when I look at other packages.. I get the hee-bee's and wonder how people can ever be efficent w/ them. I guess you get used to it, but.. I know that when it comes time for me to stand on my own two feet [ start my own business] it will be w/ SolidWorks in mind, regardless of the cost.. I've already spent as much on a CAM, I'll have more into software than hardware before to long..

Jerry

[fpworks]

For a CAD system, I highly recommend Solidworks or Pro/E. Yes, they are expensive, but it is worth it in many ways, trust me here. Pro/E costs the same as Solidworks (for basic packages last time I checked)

I don't know anything about Alibre or Rhino, but I wouldn't waste my time if they are not parametric based solid modeling packages. Whatever you get, evaluate the program's ability to handle assemblies, create drawings from models, and speed and ease of model modifications.

Make sure the software can export the models as IGES (*.igs) or STEP (*.stp) files. These are the two most common "generic" 3D model files that any CAM system should be able to accept.

[BobWarfield]

http://www.cuttingedgecnc.com/cncmain.htm

A fellow CNC + R/C Helicopter enthusiast. Lots of good learning materials on his site.

Best,

BW

[JerryFlyGuy]

I've used Rhino a couple times, not that I'm an expert but the big issue I had w/ it was simple that you can't change stuff.. if you go through and make a part, say you start w/ a block from a simple extrude and then put a bunch of cuts and what not, then later realise that the block is just a smidge to big or small.. either you start over.. or you undo the 50 steps or [however many steps there was to making it] w/ something like solidworks its as simple as selecting the first feature in the feature tree and changing the dimension.. every other feature updates automaticaly. This might not seem like a big deal, but wait until you do a part/assembly that takes you several hours [ say 30] and you find that you can't make the last part work because of mat'l sizes or whatever.. at my shop rate thats over$1800 worth of wasted time if you can't fix it easily.. not to mention all the time to redo it.. call it a $4000 mistake if you will.. it doesn't take to many of those to make a slightly more capable software set to be worth it..

Oh.. and then there's the lack of parametric's, linked equations, moving assembly tools, top down assembly.. etc etc.. I guess I need to learn how to count.. I think that might be one or more.. more than one..

Jerry.. [jaded by 4yr's of Solidworks..]

[ormandj]

Thank you everyone. Jerry, I found this problem too. I'm trying out Alibre right now to see if it will work. I have a seminar on it on Monday, so we'll see how it goes!

[JerryFlyGuy]

Let us know.. make sure it can do decent drawings and dynamic or mated assembly parts as well as parts driven by the dimensions of other parts, these are things that are going to make your life [designing stuff] much.. much easier.. you'll save money in the long run if you get the correct program from the start.. trust me on this... but don't ask me how I know..

Jerry...

[ormandj]

Hehe, I learn the same way as you apparently. I'll let you know how it goes once I finish all this training stuff. It's a parametric program, and I know it can do assembly, but I don't know much more as I'm no good with it now! Hopefully over the next week I'll figure out more and be able to report back my findings.

Cheers,
David