WorkBee to QueenBee Pro

Posted on October 25, 2022 by Max

This post covers the upgrading of an Ooznest WorkBee Version 2.2.1 with the Queen Bee Pro Linear Rail upgrade kit. It’s probably also relevant to anyone with later versions. Earlier versions (2.2 and earlier) are different.

When I decided to fully upgrade my WorkBee to linear rails it was really just a toss up between continuing with the WorkBeeCNC designs on Thingiverse like the Z-Axis Linear Rail Upgrade, which I had already successfully completed some months previous, or go with a Bulkman QueenBee Pro Upgrade Kit. I didn’t consider the Ratrig or other alternatives because they were not really on my radar at the time. I had two purchase routes – via Aliexpress as below or slightly cheaper directly via the Bulkman3d Website. Finally I opted for Paypal Pay in 3 which worked really well.

During the upgrade I’m taking the opportunity to tidy up and complete the spindle upgrade I completed last year and will cover this in another post.

The Kit

Prior to purchasing Bulkman sent me the following BOM to ensure the correct kit was sent. Unfortunately, Ooznest don’t provide the same level of kit detail so it was not easy to make a direct comparison. What follows is a guide to the dimensional and constructional differences that I had to work around.

General comments.

In general the quality of the parts sent has been good. One of the carriers had poorly threaded mount holes and unfortunately my tap snapped off when I was trying to clean the threads so I had to replace this.

A number of the shorter 10mm bolts did not have fully pressed sockets for the Allen key and I had a few uncomfortable moments removing spoilt bolts from the machine when I realised I wasn’t going to be able to tighten them sufficiently or might struggle to remove them at a later date.

I was grateful to WorkbeastCNC for their Workbee CNC Linear Rail Alignment Tool Workbeast CNC Mod which I was able to print and use to align the linear rails.

Thrust Bearings

Based on the statement in the BOM above I expected to find these in the kit but they were missing. Impatient to get the build completed I ordered some from Simply Bearings in the UK. I ordered:

which cost ~£40. In addition, I took the opportunity to replace the original bearings which are moved to the inside with 6 or 8 x SF688ZZ Budget Metal Shielded Stainless Steel Flanged Deep Groove Ball Bearing 8x16x5mm depending on whether you want to replace those on the Z. Bulkman3D issued a $3 refund for this oversight.

Motor Mounting

The new bearing configuration requires longer motor mounts consisting of 55mm screws and additional 6mm spacers. The Ooznest kit doesn’t include 55mm Low Profile Screws and they are not provided by Bulkman so these were also purchased from eBay.

You can use 60mm screws to fit the X Motor Mount and they are probably a better fix as more thread gets screwed into the Y Plate. Due to obstructions the Y Motors need 55mm behind the Extrusion.

Screw Blocks

Since version 2.2.1, Ooznest have included offset 8mm Acme Screw Blocks. Prior to this they used Open Builds Acme Screw Blocks with an 3mm Aluminium Spacer and a Precision-Shim. Simply, this meant that once installed with the Bulkman kit the screws do not line up with the plates.

After some delays in the responses to my communications with Bulkman I sourced some original OpenBuilds Acme Screw Blocks from eBay and made some spacer shims.

By calculation they should be 1mm. The recess in the back of an open builds block measures ~2.5mm. The old kit provided a 3mm spacer and 0.5 precision shim. However, in the end 0.5mm seemed to fit best.

I designed and 3D printed these in ABS – you can download the STL file here from 8mm-acme-block-shim.

Drag Chain Mounts

None of the Ooznest Drag Chain Mounts work due to the changed distance between the extrusion and moving plate so I have redesigned them for the new mounting positions. The Y fixed end attaches to the extrusion that supports the drag chain and is fixed in place by the Y Extrusion supports. They are available to download from x-axis-drag-chain-mounts and y-axis-drag-chain-mounts.

Limit Stops

Due to the addition of the HGR rail and carrier all the limit stops needed to be realigned with the plates. I designed 3D Printable mounts and printed them in ABS. They are available to download from limit-switch-stops.

Screw Covers

Due to additional bolts on the Y Plate securing the X beam the original Screw Cover would not fit.

To be finished

Y-Axis Binding Plates

The QueenBee Pro kit stiffens the Y-Axis extrusions by inserting 4020 extrusion into the space within the 8040 C-channel Extrusion. In the instructions they talk about these being potentially hard to get into place and needing a soft hammer. On the other hand mine dropped into place and would slide around. Even once the ends were secured there was some flex in the middle section. I decided to make a plate that would hold the central portion secure. It might just be a POM addition and add no actual structural stiffness but they are fitted non the less. They can be downloaded from extrusion-side-bind-plate.

Further Modifications.

Faulty Screw

During the rebuild I discovered that one of my original Ooznest screws was over-sized. Just one of the three 1000mm screws would not allow bearings to slide over it. Double checking against an older 800mm screw supported the conclusion. I ordered a new 1000mm screw and this confirmed a single oversized screw that has now been retired.

Slimline Router Adapters

I decided to remake the adapters used for the router mount and dust shoe in a slimmer style. They can be downloaded from openbuilds-router-mount-adaptor-66mm and 66mm-dust-shoe-adapter.

Spindle Z Beam Cable Mount

I wasn’t happy with the flex and tension on the cooling connections at the top of the spindle so created a mount to take some of the strain. It can be downloaded from workbee-spindle-cable-mount.

Cable Tidying.

I used some Clip in Cable Covers and Cable Clips to tidy the cable runs.