[stevespo]

Some projects never get finished because life gets in the way. If our lives depended on these machines, we probably wouldn't be building them nights and weekends.

That doesn't mean that there isn't a lot to be learned. It's valuable to document them from the beginning to benefit from the thinking that has gone into it. Both the good and the bad.

Zach, we're enjoying your process. Keep the discussion flowing. Everyone else should be honest and constructive with your comments and criticism. If you don't want to read it or you think there needs to be a deadline associated with it - move on.

Steve - Is a DIY machine every really "done"?

[Zach_G]

Geez, I come out of winter hibernation and look what's going on. I was hoping this thread would slip back into obscurity after being brought back to life, but doesn't look like it's happening. I'm sorry to everyone this thread has offended with its content (or lack there of). It wouldn't keep coming up though if it weren't bumped every few months. Although I am a bit flattered by the fact this thread shares space on someone's calendar.

To those upset with the content, I'd like to say this project has been substantially more than "just a few hours of CAD". The CAD alone has probably involved 50+ man hours over the evolution of the design, specing out everything down to nuts and bolts. Additionally, much effort has been put into engineering the best possible machine to meet MY personal needs with the components that are already paid for. I've written MATLAB code to simulate axis performance, and done FEA to gauge ridgidity. Personally, I think the amount of time and effort put into it is worth sharing, and also appreciate viewing the other "vapor" designs out there; it seems a few others agree.

I still welcome the negative feedback pertaining to the design. It's one of the reasons I've been hesitant to start building. That and life has priorities, this is after all just a hobby!

So thanks everyone for all the support, but before we all start a flame war and bring about the almighty wrath of the mods, lets limit the comments to constructive criticisms. Kinda embarrased actually that I've brought about this bickering in an otherwise informative and professional forum. Promise I'll only post updates of physical progress (It won't be built by GITERDUN's deadline, you win) so there's no need to ask or point out lack of progress =)

Well, I'm done for now, and so should all of you!

[digits]

I think XKCD said it best:



Zach_G - as everyone on here should know, the first rule of voyeurism is that it's bad form to tap on the window if you don't like the action! This is your thread and your hobby - we're all just passengers who can get off if we don't like where it's going.

From what I've read so far, you've got an interesting design and a good stack of bits - IMHO if you've got the time and the money, you might as well have a crack at building it. Modelling is all good and well, but I think there is a danger that it can lead us to dismiss designs that while not optimal, are probably good enough. Once you have it built (or usually half way through) you can start thinking about how V2.0 will be so much better

[LeeWay]

On each and every one of my machines, the design or first build was always upgraded for the better. I always started with my smallest motors and cheapest controllers. Always used good parts though, so mots upgrades were with the electronics. The only time I ever really completed a design to work from, wound up changing a bit, but not much. That was my lathe. It did get better electronics though.

Designing on paper so to speak is a very useful tool, however there is not much in the way of real world testing. Experience of others here certainly helps as does good constructive criticism.

I say start with the base. Throw it down. Take a pic. Viola, the start of a project.

[Stbrnrd]

Hey zach_G
Nice design concept, it's not about accepting defeat, but overcoming the impossible. You have a design in mind and your first post was to ask people for their opinion, well ok, there are some that are just ignoramus and negative in every aspect, but there are more that are constructive criticism. Having said that....continue on your challenge, and tweak your concept until it is perfect in your mind, then make it happen, if it fails, money is all you have lost...but if you succeed, no one can take that chip off from you then.
Ok back to the model... Very stout, although for the speeds you are trying to achieve, do you have a software brake or limit switching capability? Reason for asking it the canter lever effect will make that spindle motor and Z-axis weight magnified by the speed in which it's moving towards the rear (noticed that the front has more length support) not sure if that was thought for that reason...but look into it. Is the weight of the gantry over all going to be supported by the four bolts that hold the arms to the X-axis (what is their shear-load at the head after torque)?? If you were to make the gantry arms bolt to a plate 1/2 the size of the X-axis, then float the X-axis on the linear bearings you will have less issues with momentum and shaking of the unit.
I made a similar system but I used extruded aluminum (for a bench-top unit and asides from the fast speeds you are looking for) it served a well worth effort, someone made me an offer I couldn't pass up, so I sold it. Currently working on my second version (improved) hopefully. But I like the effort and dedication you have put in your design. Don't let the "haters" cloud your vision, keep going until u make or brake. That's how you can say I've learned from experience.

Cheers n hope to read about this soon.

[GITERDUN]

Well, we're pushing 3 years now since the beginning of this project. Wonder how the mill is working? I haven't been able to check in too much, as I bought and remodeled a house during this time as well as restoring an old Austin Healey.

[Zach_G]

Here's the conclusion of this project Stbrnrd, another thread was started since this one veered off track. Theres obviously a large gap in the design evolution which was not shared since I didn't care for the heckling. http://www.cnczone.com/forums/vertic...trol_mill.html

[dick cnc]

Very nice I'm starting a small mill build now myself the base for my Z is a large cast iron right angle plate 8 x 8 x 18 x 1 1/4 inch thick with angle web with aluminum flat stock for base 8x1 1/2 inch thick linear ways size 20 for X and Y size 30 for Z 16 x 5 mm ballscrews plus three-quarter inch aluminum plate for the rest of the odds and ends with a X 2 spindle