DIY or Purchase a Kit???

[C.Des]

So I've been back and forth on building my machine from scratch or buying a pre built kit, either an 8020 kit or another mfg. who happens to have their aluminum machine in the mfg. section.

Knowing very little about cnc beyond my research here on the zone cooking my brain and I'm at a standstill. I was set on purchasing an 8020 machine but feel like there are quite a few things left to be desired on the machine I was interested in. The linear components amongst a few other things that I honestly don't know enough about to really make a judgement on.

The other aluminum kit I was planning on purchasing seems to be having more and more problems and I'm starting to get scared off. I don't know if the cost of getting a good deal to be a guinea pig is worth it.

I'm strapped to a small budget and trying to decide on what's best for me...

I don't want an mdf machine I know that.

I'd like to get some other peoples opinions that have built their machines from scratch or purchased a kit... If a kit which one did you purchase and what's your honest opinion on it? If there's something you don't feel comfortable saying in the thread please pm me.

If you designed your own machine what are the things you'd do differently?

What were the best investments you made?

I'm not trying to pick anyones kits apart or badmouth their hard work... I just want to know people's personal experience pro's and con's to better help me make the best decision on how to make my next move.

Thanks in advance for your responses! Without the community here I'd be lost.

[FandZ]

I'd feel comfortable recommending the kit that's made from Ahren's parts even though I don't have one. Plenty of people have gotten their machines and are satisfied. http://www.finelineautomation.com/st...?tag=FLA100-00 You'll end up spending another 500 or so on electronics but you'll end up with a very capable machine. I recently got 3 sets of Ahren's rollers and am very satisfied with them.

I'd definitely get a kit before trying to DIY on everything. The less you have to fabricate, the easier and faster it'll all come together. I've gone completely DIY on 2 machines. I kinda feel like I've wasted more time than anything else on them over the past year. I have learned a lot though and am feeling confident with revision that I'm currently doing.

I'd say my best investments have been, G540 driver, 80/20, Ahren's linear components, and my pillow bearings. Tool wise, parallel set, drillpress, digital calipers, and so on.

[ilya]

It really depends on what you want your machine to be capable of. Some kits may be just a ticket if they happen to be what you want. DIY approach, from the other hand, offers much more flexibility - you can build your machine from the parts you have at hand, and make it do exactly what you need it to do. However, this may be very time consuming and additional skills like CAD modelling and engineering are a very big advantage.

I can second the FandZ suggestion about Ahrens parts. They're very flexible, and are very convenient to work with.

As for me, I've chosen the DIY design approach. Howver, I've based it on Ahrens parts. My goal was to make a machine that doesn't need any custom milled parts. I wanted something that you can just bold together, align, square and here you go with a nice new CNC machine. I haven't used the free plans that are available from Ahren. In part because they weren't ready at that time, but mostly because I've never wanted a moving gantry machine. I've always felt that moving gantry design is less rigid than moving table design. And since I wanted my machine to cut metals, I've chosen moving table. Now, this is not a usual approach, and I couldn't find anything ready available at the zone. So I ended up making my own set of plans for my machine.

So, the bottom line is: if you have time, knowledge and tools, then go and design the machine. Otherwise make your best to find a kit that suites your needs.

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My DIY CNC machine plans at www.8020CNC.com

[ihavenofish]

the best investment to me is getting parts that that can be re-used.

for example, i got a sieg kx1, which didnt relly work out to do what i want. but the g540 control and all my tools and vises and such get to move on to the next machine (which as you know is the kit you are getting scared of).

and on that note.. the ball screws, hiwin rails, table sections, and spindle will all live on even if for some reason this machine fails to live up to my expectations.

you want "universal" parts for the most part, whether its full diy or a kit. that way you can minimise losses on failed projects. worst case is alot of the parts have decent resale value.

i got some thk slides, some parker servos, milacron ball screws, siemens motors for various diy project over the years, and none ever made it to any use because they were bought with only one project in mind, and arent applicable to my needs anymore. none of them can be sold for alot of money either, because noone else wants them either.