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samualt
09-05-2003, 12:10 AM
Well, I'm still looking for plans/kits and have some questions also. So here goes:

Comments:
I looked at the MachineToolCamp (http://www.machinetoolcamp.com/) plans and they looked pretty good. But I sent them a list of questions and never got an answer. MSL Direct (http://www.msldirect.com) seems to have some kind of "kit" for the MachineToolCamp plans, but as far as I can tell its just "The Black Diamond Linear Systems prepackaged for use on Machine Tool Camp Router Systems." which seems a little pricey at around $1200.
I also wrote an email to CNCKit's Doug Fortune (http://www.cnckits.com/) to ask about his upcoming router kits. But alas, no answer there either. His kits sound like they will be fantastic if he ever finishes them. I'm keeping an eye on his site.
I looked at the other plans out there but didn't see many I really liked. I wanted something a little better than just a small hobby machine which is what most of the plans seemed geared for. And, I wanted something that didn't require me to be an engineer also. I guess I'll keep watching Mr. Fortunes site and see what he comes up with.


Questions:
1. I keep seeing ads for computer controller boards. Isn't that what the Gecko's (http://www.geckodrives.com/products.htbml) are for? (Computer->parallel Port->Gecko->Stepper/Servo Motor). Are the computer controller boards supposed to take the place of the Gecko's?
2. Why is a spindle better than just a router mounted on the gantry? At least thats what I gather from things I've read.
3. What do most of you do for a power supply on the 600+ inoz motors and such. CNCKits looks like they have a very nice one, 1.5KW. But I have no idea if $400 is a good price. I think I can scround parts for cheaper.
4. Is having a vacuum table a big boost? That is, is it really worth the trouble to add? Will it hold parts to the table really hard (like I want it to)?
5. Anyone have a good source for big stepper or server motors? 600+ ozin?


Well, enough newbie questions for now. Thanks for any info you can give me.

ninewgt
09-07-2003, 05:04 PM
SAM

How big of a machine do you want to build - and whats a ball park of your budget ?

samualt
09-07-2003, 07:26 PM
I'd like a machine that is at least:
1. 4 foot by 6 foot for the XY planes. 6 inch Z plane.
2. 600+ ozin steppers/servos.
3. Aluminum moving gantry type.
4. Uses professional guides of some kind (No skate wheels on plumbing pipe :-)
5. Has possibility of adding vaccum on router/spindle mount. This shouldn't be too hard to do to most of them.
6. Has possibility of adding vacuum table (later at least. Probably can't afford that now.)

I'm looking to spend $3K - $5K US. The lowest price I can get away with and still have a decent machine. I've also been looking at used cnc routers but they never have all the features I want for the price I want.

The Machine Tool Camp design looks pretty much like what I want and in the correct price range, at least to get started. But I would rather have a nice kit for the mechanicals-only part rather than having to scroung; Which is why I'm keeping an eye on CNCKits.com because that looks pretty good also. Neither have returned emails so my confidence isn't very high for these.

ninewgt
09-07-2003, 08:01 PM
I can lend a little insight here.... as you may have seen I just built a 4 X 8' router I designed.
First on the motors - dont get locked into thinking you HAVE to have 600 Oz In motors. You will size your motors based on the required torque. In the price range you are looking at as far as the machine size goes I doubt you will need 600's....... I have 470's on mine - stepper motors and my machines gantry is very stout and pretty heavy - about 230 pounds and it will move along faster than I am going to cut anything..... The big thing is when building your machine you MMUST keep everything straight, level, paralell........ then your gantry will slide effortlessly. When I pushed my gantry (before the rack was installed and engaged) I could shove my gantry with a finger and it slid the length of the machine - thats what you want... if all your parts move that way you will be fine with smaller motors - I too was worried about motors and had people tell me Id need 1200 Oz In, and all kinds of stuff.... but my machine is fine.
Next topic.... On Machine Tool Camp - Scott, the owner is a busy guy - not only does he sell plans - he sell CNC machines and is quite busy - I purchased his plans before deciding to build my own machine - though his plans were good - I wanted a stiffer tighter tolerance machine. I had trouble reaching him by email - about the only way to get a response is call him.
I also purchased plans from DataCut. His plans sound more like you are looking for. If you want an aluminium gantry type machine - Im not sure if you mean extrusions, or machined tool plate like the DataCut or my machine.
What are you going to do with it primarily ? You should realize that if you want to use quality components and build it with Aluminium plate, 5k is what you will spend to build a machine that size if you do some shopping.

As far as parts - you dont have to scroung if you simply have a good set of plans as MTC plans, and DataCut both have good parts lists as well as a list of where to get it.

I did a ton of research on it all before I built my machine because I wanted the features you described but also wanted a bigger machine. When I couldnt find one - I designed on and in doing so I learned A LOT.
A piece of advice..... If you want to use good bearings like you said - Use 3/4" on your X and Y axis. Do not use 1/2 or 5/8... Look up some pricing from Kerk, Specialty motions, etc... based on your x and y axis length... This will tell you how much you have left to work with. You can then get creative with HOW to build the machine. You can allways purchase plans as a knowledge base as I did and design your own - especially if you have a cad program to draw with.

Anyway - just some advice from someone who was in your shoes 3 months ago..... I am no authority on the subject at all.... just someone who learned a lot doing just what you are starting.

turkgeltz
09-07-2003, 08:39 PM
You might try looking at these. http://www.pump1.com/vmax/kits.htm


There're very heavy, the 2x2 is 385 lbs and you need big motors to run it.

samualt
09-07-2003, 11:40 PM
turkgeltz:
Thanks for the link! I missed that one. That thing is built like an armoured tank! LOL. I'll certainly keep it in mind.


ninewgt:
Thanks for the insights. I have taken it all to heart and have adjusted my wish-list. Especially the part about "Use 3/4" on your X and Y axis". I think the cnckits.com model says it will use 1", cool!

The problem with many plans is, especially when using aluminum plate, is that they assume you have access to a cnc machine to cut the parts. I don't. So, digital plans and/or cutting templates does me little good. It would probably end up costing me the price of a nice used ShopBot to go to a machinist and have all the pieces cut. This kinda leaves me with two choices:
1) Find plans that require a minimum of tools, like MTC.
2) Find a nice mecahnical-only kit to put together like cnckits.com. I think I can wrangle the rest of it by myself. The only problem with the cnckits kits is that I don't know when/if he will release them.

I guess for now I'll just play like the squirls who gather nuts for winter. I'll gather as much info as I can for the hard road ahead.

-------------------------------
"The present is theirs. The future, for which I really worked, is mine." - Nikola Tesla

ninewgt
09-08-2003, 09:31 AM
3/4" is great - 1" even better.... but I dont think you REALLY need it that big......

Why dont you email me ? I have a few things Ill run by you that will really help.

send to

eightwgt@aol.com

Carver
11-16-2003, 01:49 PM
On your question about router vs spindle,

The high frequency spindles are far more expensive than routers. They also offer several advantages that I would have a hard time justifying for anything other than commercial work. They typically use a frequency convertor to turn our 60hz electricity into 300 hz electricity. These routers are far more effecient electrically. This results in vastly cooler operating temperatures which directly affects lifespan, usually these are completely sealed armatures with only small exterior fans cooling the case. This makes them much, much quiter than conventional woodworking routers with a fan spinning at the same speed as the bit. The elctronics that drive the spindle are very expensive also. They are somewhat tempermental about supply current from the grid.

On a machine running several hours a day in a commercial environment the spindle is very much justified.
My inclination is to design for the weight of the spindle, use the router and upgrade when economics allow later on.


Best of luck,

Phill Pittman
www.masterwerkes.com
digicarve@verizon.net