Zenbot 12×16 CNC Intro photos and info

I’ve been meaning to get around to this post for a while but never seemed to make time to do it.  I recently joined the Unofficial Zenbot User’s Group on Yahoo Groups and someone asked about IGUS wire chain.  Since my setup took some “perfecting”, I was more than happy to post the dimensions to the group.  I also promised I would take pics, so here they are!

In December 2010, I purchased a new house with a garage which meant I now had space for the Zenbot CNC router I had my eye on for some time.  Being a gadget geek, the next logical extension of programming and gadget is to buy gadgets to make other gadgets with!  I had been lurking on a few of the CNC forums (mostly CNCZone.com) and even though there wasn’t much information at that time, I settled on the Zenbot.  There wasn’t much about Zenbot at that time on the forums, but comparing specs, prices and availability, I decided to go with the Zenbot 12×16 model with the Hitachi M12VC mount, the optional Zenbot Control box and got the discounted copy of Mach3 control software as well.  I had corresponded with Shaun a few times before ordering, he was really responsive and answered the questions I had, mainly whether I would be able to mill aluminum with this setup.

As for spindle selection, one of the things I really like about the Zenbot was that Shaun offered several different mounts ranging from handhelds to routers.  I wanted a “proper” spindle, not a Dremel 300, Bosch Colt or RotoZip RZ1500 handheld as I wanted to do some milling of HDPE and Aluminum, and would need larger bits and horsepower to do the roughing and/or detail work in less passes.  After my reading, I settled on the Hitachi M12VC for a few reasons:

  1. Cost – it was available for less than $100 US, typically in the 79-89 range on Amazon or in my local big box hardware store where I found one “on clearance” for $69 – strangely I still see them in there on a regular basis and they are certainly not on clearance, I think they may have just been marked wrong for a week or so.
  2. Collet Size – although the unit came with both 1/4” and 1/2” collets, I quickly found precision collets available from precisebits.com with much less run out than the stock collets at what I think are very reasonable prices.  I haven’t ordered these yet, but I plan to pickup the Ultra-Precision 1618 collet kit (also works with the Bosch 1618 router) BOUP-1618-842KIT (117.95 US) which includes the precision 1/8”, 1/4” and 1/2” Ultra Precision collets, collet nut, spanner and 118 ml of Collet Care lube as well as the 3/8” Ultra Precision collect BOUP-1618-3/8 (29.95 US).
  3. Power – 2-1/4 Horsepower compared to the very low HP of the handheld spindles.  Although the Bosch 1618 has the same HP as the Hitachi, it was typically 20-50% more, mainly I believe due to the self-releasing collets that are included.

Now that I had decided on the spindle and placed my order, all I had to do was wait for the approximately 3 weeks it took for Shaun to make my Zenbot and ship it from California to Virginia.  I had a couple of weeks off to move into the new house, so a nice reward at the end of moving everything was a good sized heavy box showing up on my doorstep.

One other reason I really like the Zenbot package is that according to the website and Shaun, the only thing I had to do when I got it was mount the trestle to the X axis, mount the spindle to the Z, calibrate it and I would be ready to go.  As promised, it showed up, I did exactly the things above, plugged the cables into the controller box, loaded mach3 and started jogging the thing around with about 20 minutes – part of which was me mounting the trestle backwards, taking the hex head cap screws back out, flipping it round and putting them back in.  I then did what everyone else who just paid $1300 for a piece of precision equipment would do – used masking tape to mount a Sharpie pen to the spindle mount and started drawing things! (sorry, no pics of this setup!)

I started playing with the cable routing along my workbench and decided that I would need longer Y and Z axis cables, so emailed Shaun and he made them up for me at a nominal charge and had them to be in less than a week.

Next, although I had already ordered it back when I placed my Zenbot order, I had yet to take my Kent CNC dust shoe out of the box and mount it to my spindle.  I was attracted to this shoe over others as the shoe itself wasn’t hard-mounted to the spindle or the Z-axis – it’s two plates that are held together with magnets, so you can leave the mount on and not have to fool with screwdrivers or hex keys to get it on and off every time you need to change bits.  He also offers different size fingers – I ordered the stock one with 3” fingers, although as you will see in one pic below, the fingers closest to the end mill sometimes trail right into the path of the mill and have been given a free haircut!  Lastly, he is a fellow CNC enthusiast and his site has video of him cutting out the shoes on his own CNC to demonstrate the product.

So back to why I hadn’t taken it out of the box yet – which actually isn’t true.  I had taken it out to inspect it, so really, why hadn’t I mounted it yet.. I hadn’t cut anything yet mainly because I didn’t want to make a mess.  Don’t worry though, my plan to deal with the mess was on its way from Amazon.  Again, after much reading, I picked the heart of my dust control system – the Delta 50-760 1.5HP 1,200CFM vertical bag dust collector.  You can barely see it in some of the pics below, I have spoil board (insulating foam) stacked in front of it, so you can’t see the whole thing.  The garage isn’t out of winter mode yet, so I’ve got quite a few things in spots they shouldn’t be at the moment.  I will get more pics of the entire setup once I’ve cleaned up the clutter.

So one thing that was an issue with the dust shoe is that it is made to sit flush with the bottom of the router housing.  The spindle mount and brackets that Shaun supplies are well engineered and give the most solid mounting available – at the upper most and lower most positions once you take the router base off.  That means the bottom of the spindle mount and lower bracket sit flush with the bottom of the router.  I immediately unscrewed the mounts, pulled the router part-way out, insert the dust shoe mount above the lower most mount and slid it back down.  Problem sorted! (or so I thought) Turns out that the dust shoe frame doesn’t like a .75” piece of black HDPE insert between itself and its mount. DOH!  Unscrewed everything, pulled the router back up, pulled out the dust shoe and then proceeded to try and relocate the lower mount.  As it turns out it’s pretty hard to get perfectly aligned holes, even when using a drill press, that don’t kick the router out of plumb.  I shot Shaun (yet another) email describing my dilemma and the dust shoe and he cut me a new spindle mount .75” shorter with the holes moved up appropriately, again for nominal cost.  I had it in less than a week and next thing you know, I was ready to cut!

While I was waiting for the new spindle mount, I tackled connecting the Zenbot to the Delta Dust collector.  I use 4” clear dust collector hose by Woodstock.  I chose clear hose so that I can see if there are obstructions that need to be cleared, and also it’s pretty cool to see the dust being sucked out into the collection can when the mill is cutting.  You can’t really see much with the dust shoe on, so this is the next best thing!

As for the dust collection can – instead of using the clear collection bag that comes the Delta as the main collector, several people that left reviews on Amazon clued me in to running the 4” hose into a 4” elbow that points into a 30 gallon metal trash can, then cut another hole in the trash can lid and attach the output of that to the 5” input of the Delta.  Not only does this give you a larger collection hopper, but since the larger pieces of waste wood material get sucked up along with the sawdust, they will fall to the bottom of the can since they are heavy pieces – not a big deal until you think about what would happen if they went straight through the inlet on the motor – they get sucked through the impeller!  Once I start cutting aluminum, guess who’s going to win before too long… so I picked up a 30 gallon can from my local hardware store, cut two holes in the lid and used construction adhesive “weld” in two blast gates that I picked up on Amazon as well.  I connected the 4” blast gate to the 4” clear hose and cut a short length hose to connect the 4” elbow to the other side of the blast gate inside the can.  I connected the 5” blast gate to some 5” Semi-Rigid Flexible Aluminum Duct (be careful, very sharp when you cut it with tin snips) and then to the inlet on the bottom of the Delta induction housing using Murray 5” worm gear clamps.

I’ve also added some IGUS eChain, e16 series 33” x 4.54” x 1.54” to be exact that I bought from a supplier on eBay.  This really helps with the cable management – before I had one of those swinging plant hanger “arms” and some zip ties and you had to keep an eye out to make sure nothing got pinched.  the eChain really takes that worry away (although it took some fiddling with the mounting methods and a few different size of eChain before I have it where it’s at now.

Lastly, you’ll see in the pictures that I have a large air pump with some blue insulated air hose next to the setup.  The goal is to have this blow on the spindle to reduce heat and help clear away the chips.  I haven’t fabbed up a mount yet, and for the most part, the Kent dust shoe picks up the majority of the saw dust that I’ve cut so far (although not all as you can see in the pics).  The majority of particles that get past the dust collection system are either because I’m doing a test cut and run a sequence without the shoe itself on (you’d be surprised how much just having the vacuum hose nearby does pick up though) or the dust left in the cracks when you profile down to cut out the pieces.

Things that aren’t pictured below:  Zenbot Control Box, the Dell PC that I bought on ebay for $120 to run Mach3, Vectric VCarve Pro 6.5 / Cut3d and the controller (as well as my MakerBot Replicator when I don’t want to print from the SD card)

So finally, here are the pics! (click on the thumbnail to see a larger version)

My setup as it sits facing the bench. Control box and PC are to the left. The Y-axis eChain is actually screwed the the bench (close up pics below)

The setup if you’re standing to the right of it. Here you can see the dust shoe mount and the 4” clear hose going up to the overhead mounts I’ve setup.

The setup if you’re standing behind it (I reached the camera around the vacuum hose to take this pic).  I have a scrap piece of 1/2” think pine that the Z axis is resting on.  I don’t like leaving it to rest under its own weight with the router mounted – especially with an end mill in the collet.  This piece of scrap could stand to be 1/2 an inch or so higher as I have to press down on the dust shoe’s fingers to get the frame lip around the spindle and up.

A few pics of the dust shoe un-mounted and mounted. The first pic is of the shoe frame with fingers laying upside down on the bench.  You’ll want to leave it laying upside down when it’s off, otherwise the weight of the shoe frame will bend the fingers to one direction or the other and they tend to stay that way unless you leave it with them bent the other way over a day or two.  The second pic is with the shoe mounted on the spindle.

Here is a pic from “bench level” in which you can see the dust shoe mounted and near the center can see the fingers that have been “trimmed” by the end mill. Next is a pic to see part of the hose routing. There is a little bit of a flat spot that I need to correct by spinning the hose on the dust shoe mount, but it hasn’t contributed to any less suction than when I had it spun correctly during mockup.  I’m using some shelving brackets with zip ties to hold the hose above the bench and still allow some play for the the router is moving about the cutting area.

Here are some pics of the Igus eChain mounted.  First is of the X-axis, which I mentioned is mounted directly to my workbench top.  The second pic shows the room I’ll still have once the blue airline is inserted into the left “channel”.  One control cable in each channel and the spindle power cable is fished up both this chain and the Y-axis chain below as well.

Here is a pic of the top of the X-axis chain with the cables coming out to a 90 degree turn into the bottom of the Y-axis chain. Similar to the cable-tie down below for the power cord, I reused an existing tapped hole rather than drilling and tapping another one into the HDPE furniture.  I drilled holes in the eChain mounting lip and used longer hex-head cap screws to account for the extra thickness of the plastic on the eChain lip.  You’ll notice in a few pics that some of the bolt-heads are rusted.  These are cheap hex-head hardware that I picked up and used, not those supplied by Shaun at Zenbot.  There are also a few stainless screw heads that you’ll see that I supplied as well.


Here is the Y-axis eChain mounting.  In this first pic, we are looking at the bottom section of eChain for the Y-axis. I am using some hex head bolts, washers and nuts that I already had to mount the eChain to a 6” angle bracket, again from the big box store. Here is where I used some of the stainless hex head socket cap bolts to replace the hardware that Shaun sent to compensate for the thickness of the metal.

The second pic shows a top-down view of how the control cable comes out and runs to the Z-axis stepper motor and the thicker black cable is the power line to the router.  You can see the bracket I made using some 14 gauge flat stock I picked up, again at my local hardware store. I drilled and tapped the HDPE next to the stepper mount and again am using two hex head socket cap screws to mount to the furniture.  I used some hex head bolts, washers and nuts to mount the eChain to the bracket.


Now around to the Z axis.  I am using a C-clip style plastic cable clamp to keep the cable in one spot with enough room for the 4” up and down travel of the router. I just threaded the cable tie through one of the mounting screws and screwed it back in. There is plenty of thread on these screws, so it hasn’t introduced any instability. In the second pic you can see the length of cable with enough play for the spindle to go up and down the 4” of travel.


Please leave any questions you may have in the comments.  I’m sure there will be plenty of requests for zoom-in pics and of the components I have mentioned but didn’t photograph yet.  Also, I’ve yet to capture a video of cutting out anything, but will try to do that soon as well.

Happy CNCing!