Waste Board location

Curious to know if the you can extend the Z travel by not using a waste board.

I’ve seen the One Finity mounted on a table. Then the waste board is placed in the center. Then the work piece on top of the waste board.

What if the One Finity is at the same level as the top of the waste board.

For example:

The table top is zero reference. This is where the 4 corners of the One Finity is mounted.

The waste board is 3/4” thick. Therefore, you lost 3/4”.

Hey Jerry,

the Z travel on the Z-16 slider is 133 mm (5.24″).

Here you can see that the Z assembly can be mounted in three heights:

With this, the distance between the machine bed (without wasteboard) and the lower end of the Z assembly is adjustable from 104 mm (4 3/32″) to 138 mm (5 7/16″):

Where the collet and your bit end is, is not defined as you can clamp your spindle more or less high into the milling motor mount. This means that even if you mount the Z assembly in the highest position, this does not forcibly mean that your bit’s end will be able to use the entire travel. This would only be the case if in the highest Z position, your bit’s lower end is exactly at the level of the lower end of the Z assembly. Usually you would not clamp your spindle slid that low into the mount or use such a long bit because you would add unnecessary leverage force which leads to more deflection under load which could increase chatter. Unfortunately the Onefinity milling motor mount, unlike on other machines (see also here, here and here), does not protrude downwards beyond the lower end of the Z assembly.

For these reasons, some people replaced the Onefinity Z assembly by a Universal Z assembly. How such a Z assembly/spindle slider could look like is shown below, see also RoverCNC Z assembly or Sorotec Z-Axis DIY-Kit “Alu-Line”

RoboCNC_Z_slider_03

The problem with a wasteboard is that since it’s intended to be wasted, i.e. replaced from time to time, it would not be wise to mount the machine’s feet on top of it.

One thing to consider is if you know that you will only use workpieces of lower height, is that it would be a disadvantage to mount the Z assembly in the highest position, because you would have to slide your spindle much more downwards into the motor mount in all cases where you happen to work on a low workpiece. Usually you don’t use the entire Z travel in a project. So for most stability and least leverage forces and thus deflection and chatter, it is the best to mount the Z assembly in a height which accomodates your usual workpiece height. Industrial machines of gantry-type sometimes have the possibility to alter the height of entire X axis with an additional W axis (as shown here), which would avoid these problems since they can better accomodate to a varying workpiece height.

A solution for being able to work on workpieces higher than 138 mm could also be not to attach the machine on a table top, but on a U-shaped base, this way gaining more room for high workpieces (or for a larger rotary axis). A wasteboard could then be mounted at a desired height. e.g with the possibility to fix a “flying” machine bed with the wasteboard at different heights.

Another way could be to use an open frame as base as shown here or here.

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Thanks for this informative response.

I have one of the very first OneFinity batch that was a preorder back in Nov 2020. I’m at not sure what’s changed from the very first 32”x32” Woodworker to present. So not sure what Z assembly I have.

The reason for my question is I am trying to decided on a table design. I am not fond of Z tracks and that’s due to me currently owning a Shapeko XL prior to the OneFinity where my waste board has a ton of holes and bind nut setup.

I am looking at purchasing the QCW frame and laying 1 sheet of waste board with predrilled mounting holes like my other CNC machine. But that would raise the waste board even higher.

Not sure how to make a frame like the QCW to mount the feet of the OneFinity using extruded aluminum .

Thanks again for the info, It’s time to get this OneFinity working.

Hey Jerry,

you find this out when you look at motor 3 settings: If ‘min-soft-limit’ is -133 mm (-5.2362") then you have the Z-16 slider. On the new Z-20 slider it is -163 mm.

My first idea was to use two 100 x 60 x 1.5 mm steel profiles with the length of the two Y rails and place them directly under the rails, from front to end, one on each side, and to put this on some base. This has much more stability as just riser blocks under the feet. But for maximum stability and versatility I decided that I will weld a U-shaped base (in the future, will show when ready).

Image: The Onefinity CNC machine’s foot.

A Onefinity CNC mounted on extruded aluminium profiles can be seen here, here and here.

Welcome to the forum!

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