Overwhelmed.. a bit of direction please

[randynh]

I am really interested in the idea of building my own CNC. I am mechanically inclined, but I know nothing about CNC. The main use of the machine would be mostly to create foam molds and maybe a little wood carving. Some of the molds would be a larger scale so initially I am think a 4' x 8'. As far as accuracy, I don't think I need anything real precise, though I am unsure of the common tolerances between the DIY machines.

I have the ability to weld and have access to these tools: welder, drill press, plasma cutter, and a band saw. I also have a lot of wood working tools and the knowledge of how to use them.

I just don't know where to even start researching. There are so many different types of CNC I have no idea what would suit my needs.

I am looking for affordable, I could build from scratch, but am not against a kit either

[RossMosh]

Don't re-invent the wheel. Go with a common design.

1. Look at the CNCRouterParts kits. A welded base with an extrusion top is a very popular way to go.

2. Look at the Joe's Hybrid design. Very similar to the CNCRouterParts kit in the method of building and the flexibility.

3. Mechmate machine. This is an all steel, all welded machine.

4. http://www.cnczone.com/forums/cnc_wo...x8_router.html

The Mechmate is arguably the best bang for the buck machine but the Joe's or CNCRouterPart's machines can be put together in a couple of weekends if you're focused and can devote the necessary 20-30 hours. Mechmate is probably 3-4x the amount of work. No matter what, you should budget around $5,000-8,000 for the project. Between all the extras, software, bits, the spindle, ect ect ect that's a realistic budget.

[CarveOne]

Two of my friends built a 5'x10' MechMate last summer. Many of the gantry parts can be purchased ready-made from fabricators, which is the route they took. More money, but a lot less build time and effort involved. Many of those parts were bent metal that they could not do themselves, and didn't want to fabricate using other methods. They are very happy with the results of their decision.

CarveOne

[BanduraMaker]

The best thing for you to do now is to scour this forum and especially the build log forum for at least a few weeks. Read through the long build threads and especially the criticisms given by the more senior members of the forum.

You'll get a lot of ideas on things that work and things that don't that way. Don't skim them either, read in detail. The especially interesting ones will be the "older" ones that start with an idea and by the end of the thread you'll have a completed machine cutting parts and you can see the logic behind the design changes made throughout the thread. You'll find that very few of them finish exactly with the design that was started!

Do this for a few weeks and you'll find that all of a sudden you're not so clueless about CNC!

[randynh]

Thank you for the replies. I dont feel unwelcomed unlike other forums I have been on.

I am uncertain the differences between the different types of cnc's. I am curios what others opinions are of the type of cnc would be best suited for foam carving 3d molds. So far I have briefly seen that there is 3d, 3 axis, 4 axis, 5 axis 6 axis. I have read briefly about gantry style (probably what I may want), robot arm, I believe there was a lathe type cnc also. Then there are the machines that work steel, wood, foam, granite, and use plasma cutters. I am sure there a ton of others also. Curious if there is a write up somewhere explaining the different types and features

I have forgotten a key piece of information that may would be helpful. My brother in law, which owes me a big favor, runs a family business. The business is a machine shop. They have, what seems to me, like everything. They produce dyno's. I am sure he could help me out with this. If do get plans for key pieces I think this could really help

[HorridHenry]

there are the machines that work steel, wood, foam, granite, and use plasma cutters.

You can have all these just by thinking about the bed design and gantry,and the material its made with.
I think Mild Steel box section is the way to go for all the above.

[awerby]

If what you want to do is carve 3D molds from foam, you'll be building a much different machine than if you wanted to cut things from steel or granite. If you're making boat hulls, you'll need a long Z axis, but if the biggest mold you're making is only a few inches high, then a shorter one will suffice, and your machine will be more rigid. If you're a good welder, then starting by building a stout table from mild steel tubing makes sense, although many builders use aluminum for the gantry and other moving parts to keep the weight down. If you're new to this, then starting with a Cartesian 3-axis machine would be simplest; you can add extra axes as you need them. What with all the motor-mounting plates, etc that you'll need, I'm sure you'll have ample opportunities to call in that favor from the BIL...

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

[crane550]

Don't shy away from trying your own design too. If your good at welding I would suggest a steel base. Not everyone has the ability to work with this, and it is a bit more work but not necessarily more expensive. I make my base to be about 1,200 lbs and it only costed me $200 for the steel. You can get really good deals at scrap yards.

I would simply suggest combining all the aspects of the machines you like. Look at the results from the machines you like and do what they do. We will be here to help you! Good luck!

Alex

[adprinter]

I am really interested in the idea of building my own CNC. I am mechanically inclined, but I know nothing about CNC. The main use of the machine would be mostly to create foam molds and maybe a little wood carving. Some of the molds would be a larger scale so initially I am think a 4' x 8'. As far as accuracy, I don't think I need anything real precise, though I am unsure of the common tolerances between the DIY machines.

I have the ability to weld and have access to these tools: welder, drill press, plasma cutter, and a band saw. I also have a lot of wood working tools and the knowledge of how to use them.

I just don't know where to even start researching. There are so many different types of CNC I have no idea what would suit my needs.

I am looking for affordable, I could build from scratch, but am not against a kit either

Without re-posting the file, have a look at http://www.cnczone.com/forums/attach...1&d=1330494126 for details of what I did on my first build. The file also contains info on other websites, software, possible hardware sources, etc. As others have suggested here, it is best to do as much research as possible. This will help you to decide (or at least obtain an idea of) what type of machine you would like to build. But one word of advice: BUILD IT AS RIGID AS POSSIBLE! Most folks think that a machine to be used for just "simple engravings, etc." doesn't need to be a very heavy duty machine. But the reality is, unless you have a machine which is very rigid in it's design and construction, repeatability is near impossible. And when it comes to engravings, multiple passes are almost always required to get the best results. Unless the machine is a precision built design, the second, or subsequent passes of the cutting tool won't line up exactly with the first pass (resulting in double lines, or even triple lines being engraved, instead of simply cutting the first lines deeper on the subsequent passes). When I first decided to build my machine, I did not even have a plan drawn on paper yet. I just jumped in, with building a basic 2 foot x 4 foot steel table- and just kind of went from there! Seems a lifetime ago now, having gone to the school of hard knocks along the way. But the experience it has taught me, as well as the advice I have received from this forum, and others is priceless! Good luck with your project.