Looking at bringing a new Z axis to market

Thanks @JoseD3

@Stari I’ve just pmed you

As a small update - I’ve brought things forward again. We’re now in the hands of suppliers.

I’ve just spend about £5000 on parts/deposits and sent the files through to my machining partner.

The only thing I haven’t bought is the thousands of M5 screws I need :smiley:

Very exciting!

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Does the design require using your existing router mounts or are you machining new brackets etc?

Hi Eirik

It uses your existing spindle mount but it includes my special tram adjuster that should make tramming a breeze.

If you use a larger spindle it can also accommodate a 2.2kw spindle - and I’m looking to offer milled versions of these brackets.

Luke

Well leave it to Beaver, not taking the role of Eddie Hasker here, but this newbie owner os an S3 is clueless as to what either of these options does, who they are suited for, and just what is it about them which adds value to the existing device?

My wish list for C3D Create and motion is for them to add more basic features making it more Inkscape like. A measuring tool, a means to copy an object from an existing file then paste it into an entirely new file. A means to align type to a curve or to a shape, a way to create “macros” such as a box where all one need to do is supply the dimension info and voila, all sides, ends, top and bottom are created and positioned on the stock ready to be cut. Finger joints would be great but I see the built-in error factor of the bit radius at each corner. I’ve no idea what the brain trust in Torrence, CA is working on, but there is no shortage of seemingly easy software additions which would add great value. Nice hardware, not so impressive software. If I’d only known at the time. Sure you can do this and that. They neglected to add if you use other software. Not your day to keep them either but surely someone there reads the community traffic. Hope to learn more about your efforts.

Bob aka Beachbob

Doing finger joints in Carbide Create is explained at: CNC Finger Joint Box

Hi Bob

There are a number of reasons you might want to consider a Z/X upgrade. I would say it’s not designed for a beginner - more of something to upgrade over time if you feel you need it. There are many Shapeoko owners who will find the standard setup suitable for there needs.

Here are some reasons you might want to upgrade at some point:

  • The stock Z/X does have quite a bit of flex in it. This does it’s most to minimise it - granted it still uses V wheels on the X but they do have a tighter tollerance.
  • The stock Z can get blocked and or jam - this one can’t.
  • The stock Z/X can skip steps or slip - it’s allot less likely this will do either.
  • It allows for a larger spindle i.e. 2.2kw - with little or no chance of slip.
  • It has a higher plunging force.
  • It offers a great height on the Z.

Best

Luke

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Hi @Luke ,

Happened upon this thread and am interested, however I see that you are reusing (or potentially rebuilding) the S03 spindle mount. The least rigid travel direction is in Y, which I believe is due to the V-wheels on both the X and Z axes being loaded perpendicular to the rail, but also due to the relatively large moment on the spindle mount, which has a very small load bearing footprint. I experience significant chatter when cutting deep passes in the Y travel direction, which is the limiting factor for feedrate on my machine. At the same speed, cutting in X is very smooth.

I ask this because it seems that you’ve done a ton of work to improve rigidity of this carriage replacement, but (to my eyes) are leaving the “easy rigidity” on the table and limiting the usefulness of the rest of the system by not replacing the spindle mount with a design that incorporates two rings to better resist the moment on the spindle. I have to imagine this will be compounded by the addition of the tramming mount, which will concentrate that moment onto the adjustment screws and the thin plate they are housed in.

Hi Josh

Your feedbacks really interesting. Whilst the Spindle mount has a small footprint it have very little flex in any direction - when it’s clamped down to a flat surface you have to apply some serious pressure for the mount it’s self to move. Granted you might see some twist on the V wheels you should not see chatter. I myself ran a 2.2kw spindle with 80mm mount with only 2 M5 bolts and got zero chatter - I’m not stating that is ideal, but I do believe the spindle mount provided with a shapeoko is adequate for the dewalt.

If you feel it’s weak I do have a solution mind - I’m offering up a machined 80mm spindle that clamps to the front with M6 bolts. It does mean you need to upgrade your router to a spindle mind :smiley:

On a more serious note, if your getting chatter on a regular basis something is loose or miss aligned. In some cases the V wheels might be deformed or damaged, even not tight enough. The Chatter can also be caused by a slack Z belt as it doesn’t hold the axis in situ properly, thus when making a cut the router is bouncing.

I have also made adjustments to the V wheel spacing allowing for those V wheels on the X carriage to be tightened more than usual.

Best

Luke

Hi Luke,

Good to hear you aren’t seeing issues with your setup. The first question I have in hearing that is: what were you cutting and how were you cutting it? I’m seeing enough chatter to have a scalloped and ugly edge when cutting a 4MM depth pass, 750mm/min in HDPE, 2 flute 1/4" carbide end mill, full width cut (slot), climb direction. That’s running the DWP611 somewhere on the low end of it’s scale, between 2 and 4 on the little dial.

The machine is only about 1mo old, I’ve recently tensioned the z-belt, and v-wheels are in good shape. If I apply pressure in the Y direction to the endmill, I can see visible movement. I haven’t measured it, but I would guess it’s 0.050" or more with firm finger pressure. Not so in the X direction. I’m not surprised by this as I’ve seen video reviews with the same behavior and it’s the primary reason I didn’t buy an x-carve. Rigidity is pretty much the top metric for machining quality and speed and it’s weirdly underestimated as the source of all kinds of problem in the hobby community.

I cut allot of aluminium, but I also use a 2.2kw water cooled spindle with bits varying from 1mm all the way up to 10. I would say at 4mm DOC you might want to lesser the DOC and increase the feed speed. If you lessen the load you might not get the chatter - give it a try as it suggests a fault. I did get some aweful chatter once - my spindle hadn’t been tramed - also worth a look.

I’ve had my machines for almost 2 years now, and I would say you learn allot as time goes on. Many of my ‘faults’ were self inflicted.

You will always get moment on a hobbyist machine - bear in mind these are cnc routers and a half decent machine centre will cost you 10k and only be able to cut a 20cm box… With the current setup you have multiple areas of flex, however these are not due to the spindle mount but down to the v wheels - currently you have 8 on 2 fairly flimsy supports. Whilst my design have 4 wheels they can go tighter and they are directly attached to a 15mm plate with 2 15x15mm steel supports…

In first instance tighten your v wheels, check y belts and pulleys, and lower that DOC.

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Josh, are you confusing x and z axis labels? X being left to right, Y being front to back? Are you getting chatter left to right or front to back?

If you are getting scalloping, make sure you can slide a playing card between your steel wheels and the aluminum extrusions. If the steel wheels come into contact with the aluminum, you will get some waves in your cuts.

I agree that the wheels on the Z carriage are perhaps the largest weakness of the design. Someone recently posted a thread with an upgrade involving mounting linear rail to the X beam, and a trolly that rides it to the Z carriage.

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@Luke thanks for the hints. I’m going through 3/4" HDPE so more looking for a faster roughing method - the scalloped edges aren’t a big deal since I can do a full depth finishing pass at the end if they bug me. Decreasing the DOC would definitely improve the chatter but really I was hoping to do more, hence my interest in your z axis.

I will admit that I haven’t trammed the spindle yet and acknowledge this may be the source of some problems… it’s just such a PITA I haven’t been willing to disassemble the machine to get it done. I did double check deflection as described and it is not insignificant. While difficult to tell without measurement, much of it appears to be as you say in the v-wheels. My comment on the spindle mount may indeed be off the mark.

@cgallery I’m describing chatter when the machine is traveling front to back, so the y axis. I’m not sure what the “steel wheels” you’re mentioning are. Aren’t they all plastic?

Also, I’m sensitive to hijacking this thread from Luke’s fine Z-carriage to troubleshooting my machine. If I want to continue this further I’ll start a separate thread, but I very much appreciate your comments so far.

How’s progress with the linear z slider coming along?

@DCFYI - thanks for the prompt I have been updating my backers via email but not posting anything on here. I’ve just sent you a PM as I’m assuming you haven’t had my emails?

The majority of stock parts have come, I have the custom milled ball screws, motor stands thousands of screws, switches. I’m expecting the custom cut linear rails and sliders today!

Annoyingly I’m waiting for a few small nice to have but not critical parts - V wheels and eccentric nuts which were ordered ages ago but are taking their time to come from china…

The custom milled parts are in production and I’m hoping for some pictures this week. There is a possibility that they will be ready next week but it’s more likely the week after. If thats the case assembly and shipping isn’t far out :smiley:

I’m also having conversations with the guys at suckit and we’re spitballing on some designs.

Yehhh!!! I just had the heaviest box ever arrive!

Custom ground rails and blocks.

7 key parts off a complete setup.

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Nice looking bit of kit, that. Properly Knolled, even. Can’t wait to hear feedback from the first round of users.

ALWAYS be knolling :wink:

I had to Google this :joy:

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Next time you post a pic, make everything juuuust a bit out of square.
Some parts just a bit too close.

Some a bit too far.

Some. . . . .randomly. .spaced apart. . . . . . .with . . . . . .no. . . pattern.

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