Project 024 - Lathe Refurb Project
DISCLAIMER: This video is educational only, so if you decide to do the same yourself then you are on your own, I can't be held responsible for any problems/issues/damage/injury that may occur if you decide to follow this blog and try it yourself.
INTRO
Having a acquired a sorry looking "Hobby 818" lathe from a friend of the family some months ago I decided it was about time I got her up & running. I don't pretend to know much about lathe's so this project will be a learning experience as much as it will be about getting a new tool for the workshop up & running.
First thing to do was to research the lathe and see what I could find, the answer being not much! I did find the following library photo of what appears to be very much like an 818, or at least the class of lathe the 818 belongs to.
But then a kind gent (James Lynn) pointed me towards the following website and says the Hobby 818 was a Far East copy of an Austrian EMCO Compact 8 lathe (imported by Axminster/Warco possibly). If mine is a Taiwan made copy its probably pretty well made as the later Chinese versions apparently had a short shelf life. More info here.
I didn't find much else via Google, just a forum post here which shows what appears to be the exact same lathe as mine except mine doesn't have the controls or belt cover.
Here's some quick links to the photos and blog below:-
Before refurb
Strip down
Clean-up & reassembly
The stand
DC motor conversion
Final photos
Video
BEFORE REFURB
So, my lathe looks a bit worse for wear as the following photos show:
STRIP DOWN
The lathe had sat in a damp outside shed for a number of years and was covered in a film of surface rust as well as various parts of it being siezed, so the first thing to do was to strip it down and clean it up.
The following photos from the strip down:
CLEAN-UP & RE-ASSEMBLY
Then it was all about cleaning up the individual parts, un-seizing them where required, and re-painting with suitable hard wearing enamel paint.
The bare metal cleaned up reasonably ok, enough that the bed would be smooth running enough for the various components. The bearings on the main chuck did not need replacing as the were sealed pretty well and the main shaft on the inside was very clean signifying that there had been no moisture ingress, not bad since the 'cover' was just the main lable "Hobby 818".
And then onto re-assembly.
It's important to re-align both the main chuck and the smaller one at the other end, so I did that with some round bar gripped at both ends before tightening own the main bolts all round. I guess this is how it supposed to be done!
And here is the lathe assembled back together again. Everything is running smooth and finger touch movement (just about anyways!).
You will notice that the plastic cogs at the main pulley end I have not re-assembled as I don't want to use them.
THE STAND
Here's the stand (bought via Ebay) positioned in my workshop. Just awaiting the drip tray to arrive then I can mount the lathe and get to work installing the DC motor etc.
DC MOTOR CONVERSION
I decided against the wheelchair motor as you'll see explained in the video further down, and I went with an electric bicycle DC motor.
Purchased from ElectricScooterParts.com and badged "Currie Technologies",
Model: XYD-6D
Spec: DC24V, 2600R/Min, 22A rated current, 400W output.
My PSU is rated at 16A, and the driver board 25A.
Here's the motor fitted. It's on short standoffs to allow the belt tension to be adjusted. The final drive is less than 1:1, so I will be getting less than the maximum 2600rpm of the motor.
Update: After a bit of experimentation there wasn't enough torque in the DC motor at low speeds plus it was a bit fast at 2000 rpm max. So, I used the lathe to turn a brass sleeve to extend the motor shaft so I could fit a much smaller v-belt pulley. Max speed is now 800 rpm, and the torque is great.
I also built a control panel by mounting a small alloy enclosure onto the lathe, the perfect place being the panel where the main lathe lable was located.
Inside the box is a 5vdc regulator in order I can generate the 2.5vdc regulated 'motor stop' voltage for the driver board. The 2.5vdc goes across the potentiometer, and the emg.stop & run/stop switch allowing additional control.
FINAL PHOTOS
Here are some photos taken of the lathe in it's final resting place, all complete.
The 24vdc PSU and Motor Driver Board are fitted in the left side leg of the stand.
An 240VAC power switch is fitted to the side of the left leg. You can see the incoming AC power coming into the bottom of the switch.
The Control panel interface cable is run neatly from the lathe and down to the left leg of the stand.
Top and front views of the lathe.
At the last minute I fitted a protective cover over the pulley's and gears........a bit of health & safety.
I also fitted a lever to engage/disengage the aux. shaft gears.
VIDEO
Here's the video that kicked off the lathe refurb.
Motor fitting and first power up / testing.
Final install - she's up & running.
