Upgrade to a 3018-pro have gone so far that I feel like it is a bit like Trigger’s Broom. Therefore, I thought I would try and list the modifications.
I think I have listed all of the upgrades on the above image. However, some changes are subtle and I may have missed them. A more detailed list and description is below.
The spindle started as a rough sketch, the idea being to mount an ER11 chuck with a straight shank in bearings and to belt drive this with the existing motor.
This was a major improvement over the original chuck fitted directly to the motor.
An upgrade to angular contact bearings improved the runout even further and reduced the noise levels.
Finally I ground the inner surface of the ER11 chuck to a more accurate 8° angle. Here you see the chuck in a larger ER25 chuck on the Warco lathe with a small handheld grinder clamped to the toolpost.
Lathe runs at 1000rpm, grinder runs at ~15,000rpm and using a small green grit wheel + WD40.
Tiamu Z-axis upgrade was significant in terms of stiffness, but as you can see this was done as part of the X-axis upgrade to rails.
The original 10mm round rails and linear bearings were rather weak.
Hence my upgraded MGN12 linear rails and bearing blocks. Plus I increased slightly the Z distance between the rails to increase the stiffness further.
Changing the Y-axis beams from 10mm diameter to 12mm diameter seriously improved the stiffness. This also meant I had to change the bearings.
On the right of the image is the original bearing and rail (10mm). On the left is the upgraded rail to 12mm diameter and the much improved bearings that cost me a bit more, but they were the same outer diameter as the original parts. Hence they fit straight into the plastic bearing blocks.
A simple and cheap solution to reducing vibration.
Sandbags sewn up and filled with dry sand add a lot of damping. This is a great improvement when machining sheet metals.
One caution is they add mass and thus can increase the inertia of the table. Hence increasing the load on the stepper motors.
The frame on the Genmitsu was easy to assemble. However, it lacks cross-sectional area and hence stiffness.
I made some simple brackets from 1mm thick aluminium sheet that was easy to bend and then bolt into the frame.
You can get carried away with stiffening brackets!
X and Y Axis Stepper Upgrade
My machine kept jumping on the X-axis and I put this down to not having enough torque on the stepper motors.
Hence I upgraded the X and Y axis motors to NEMA 17’s.
The only point of caution is that the controller has a limited current output and hence this might be the limiting factor.
Finally I checked online and realised I was running an old original version of the controller.
Upgrading to the GEN3 controller has made a significant improvement and no more jumping / missing steps on the X-axis.
I bought the GEN3 controller on Amazon for around £30.
This machine has come a long way from the one I assembled almost 3 years ago on my coffee table. There isn’t much left of the original design. I have also been on a steep learning curve.
Would I buy one of these cheap machines again? In a heartbeat.