Project: Homebrew CNC Machine

As fun as the electricity chat is, time for an update! My FTP access is back up and running - so here is Part 1 of the 'big update' (part two coming shortly):

Marking where the upper gantry-plate meets the gantry sides. You can see that I have drilled and tapped the holes into the lower gantry-plate:



Mounting holes drilled for the upper gantry-plate:



Now to drill and tap the holes in the upper gantry-plate:



Drilling holes on the ends of these long plates was a PITA with my little drill-press. I needed to undo the base and reverse it so that I had the clearence.

Gantry plates mounted up (not all the bolts are installed in this picture) and the Y-Axis plate clamped up to make where to drill:



Y-Axis plate drilled, tapped, and mounted to the gantry supports (I need to get shorter bolts):



Y-Axis ballscrew/slide assembly clamped up to the plate:



MDF top (not cut to size yet) to get a good idea of what she is going to look like. There is 5.5" of clearence between the bottom of the Y-Axis plate and the MDF top:

 

NICE i love it

 

superb work.need part 2 of the update. lol
keep up the amazing work

 

<-- I'd add about a zillion more, but that'd be a tad too redundant...

Just plain awesome. And now I'll leave you alone and let you get back to the updates...

 

are the massive parts really a must?
it seems that the alu plates and the MDF are very thick.

did you calculate that to be necesary? or just keeping on the safe side?

 

One could certainly make do with less. There are plenty of people that make capable Hobby CNC machines out of MDF - and they work for light materials just fine. However, since 99% of the work I am going to be doing is in Aluminum - and I want to do some work in Stainless Steel - I made it very rigid.

The more rigid a machine is, the better it holds tolerance. Also, eventually I will be upgrading the machine to the more accurate Linear Guides. The limiting factor in this machine, other than physical size, will be the spindle (router).

Oh, as for the MDF top being "thick". It is just standard 3/4" MDF, it is used as a spoilboard - nothing structural about it. For those that don't know, a spoilboard is a surface that your parts are clamped to and that when cutting a part through - you will cut into the spoilboard a little bit. Eventually, when the spoilboard is cut up too much - you throw it out and put a new one on.

 

Omg that's something BIG Really looking forward to see how accurate and goooood this is! I've sometimes thought about making one of my own, it would just be something smaller...

 

Must... Have.... UPpp...Dattte!!

I cruise by here almost everyday, but no update

You got a new job? AWESOME work!!! can't wait for update!

Cheers,

Mule

 

no Automatic tool changer or automatic pallet changer?

 

Great work!!!

Yeah, javadog, no automatic tool change? Really- I'm disappointed! *winks! I just stumbled upon this forum from hackaday.com and have since read the whole course of your project! I can't express how neat I think it is that you're doing this!! By the way, what was the job you got fired..err, releaved from? Also, I remember you mentioning that you're 23; how is it that you've come to have so much knowledge of machining? (I'm putting these questions to you because I am impressed, not doubtfull, just so you know! Anyways, awesome work! (I registered here on bit-tech.net just so I could post here, and subscribe!)

 

Ok, bolted the Y-Axis Ballscrew to the Crossplate.

Now to make the Z-Axis!

Here is how the Ballscrew and Linear Slide will be laid out (more or less) for the Z-Axis:





Have to drill the holes to mount the Z-Axis plate to the Y-Axis Slides:



...and counter-sink them:



Here is what it looks like bolted to the Y-Axis:





You can see that I need to make a bearing-block for the end of the ballscrew, and finish up the Z-Axis...

 

Making the Z-Axis Ballscrew bearing-plate. For ease, I decided to make it out of polycarbonate. I will make a new one out of aluminium down the road...

Forstner Bit, Poly-carb and the top OEM bearing-block:



Drilled with the bearing mounted:



Mounting holes drilled and tapped:



Re-Tapping the end of the ballscrew:



All done and mounted:





Now to mount the linear slide...

 

Dual row of holes drilled for the linear slide:



Tapped:



Mounted:



Now I wanted to add some physical stops so I didn't lose the slides off the end of the rails (big PITA):





That will do it, not going anywhere now.

Ok, now I needed to add a 1" thick block to get the mounting height for the ballscrew and linear-slide even:



Marking the holes:



Drilled and mounted:





Then I drilled and tapped four mounting holes for the plated that will hold the router to the Z-Axis assembly:



On to the Servo mounting!!

 

Laying out the cut-lines for the Servo mounting plates:



All cut:



Now, where they mount to the machine itself, I wanted it adjustable - that way I can get the belts on and tensioned correctly.

First, drill a bunch of holes:



Then, file like the Dickens:



Now to drill the holes to mount the servos to the plate:



Then using two different step-drills I enlarge the center-hole to fit the little lip on the servos. That way they will sit flush against the plates:



Perfect:



This is the Z-Axis Servo Mount, but you can see how the Servos fits like a glove:

 

Of course, I need to mount the Servo to the front plate for the X-Axis!

Here you can see where the spindle for the X-Axis ballscrew come through the front frame-plate:



The Servo-Mount all finished:



Then I had to enlarge the hole for the X-Axis ballscrew to fit the hub of the Pulley. Since I have a small drill-press that couldn't reach, I used my cordless drill (worked like a champ):



Back to the Y-Axis plate and the Servo Mount. I needed to notch the spot where the plate mounts to the Y-Axis cross-plate:





Perfect!



Except for...

 

This big glaring mistake...er rather, just something I didn't think of:



With the servo mounted this way for the Y-Axis, the Z-Axis servo would hit it when it still had almost five inches of travel left:



So, to re-work the mount and swing the Servo to the other side. I decided I would just use a second plate and make some stand-offs.

Cutting the stand-offs:



So, it would make the mount work like so:



Of course, I broke my nice 4mm tap:



Now I will leave you with a teaser of the finished machine:

 

Actually, yes - I'm co-opening a Coffee Shop/Bakery.

I would love to have a spindle that could make use of an automatic tool changer. Maybe on the next machine...

I was canned from a Technical Support position with a large distributor - but I am glad to be free of the Cubicle Hell. My Happiness and Health aren't worth $15 an hour.

As far as knowledge goes, same thing as everything I do. I self-teach myself and ask tons of questions of those who have been doing it much longer than me. Trust me, I make plenty of mistakes along the way!

 

polycarbonate Z-Axis Ballscrew bearing-plate

I'd probably replace that sooner then later i don't trust the polycarbonate to hold thoses threads under that kind of vibration.

Did you mention in the beginning that thoses servos are?? they look 300+ oz.

also if in the corse of things if you find that DeWalt a little to underpowered I love my Hitachi M12V 3-1/4 HP though it's shape may make it kinda hard to mount. But it can spin my 2.25" raised panel bit through an OAK panal in a single pass.

nice work though

 

WOW, that looks amazing and can't wait to see it finished!!! Have you tested it yet?

 

Yeah, me neither. It will be the first thing the machine cuts.

They are 360 oz-in. A lot of people have used them, with good results.

Yeah, should be pretty easy for me to step up to a larger Router should the need arise.

Thanks! Just buttoning up the power-supply and control system. Going to be spinning the motors this week.