“I have had some Micro Mesh pads for some time and have kept them in a screw top jar together with the colour code and grit information. A while ago we were given a box of Bendicks Crisp Mint Chocolates and having eaten a couple I looked at the box and realised the size of the slots the mints were displayed in was almost the same size as the micro mesh pads and exactly the same number of slots.I re-covered the lid with some brown paper and cut the colour code chart down to fit into the lid and what you see is the result. It keeps them in order and can be easily returned to the correct slot after going down the grits without having them all over the bench”Colin Bushell
Axminster AWVSL1000 Lathe Gearbox Maintenance………
Anyone who has one of these lathes may experience noise and or stiffness of operation in changing speeds. The gearbox operates on the DAF
Truck gearbox principle using friction pulleys to change the speeds over a given range using a constant speed motor.
I have experienced both of these problems, stiffness and with accompanying noise being the most recent. To check to see where the noise was
coming from and to eliminate the head stock bearing; I placed a screwdriver on the bearing housing and my ear to the handle. Any bearing noise
will be detected through the screwdriver generally at a high pitch. Fortunately, this was not the case but the noise was evident from the gearbox
area and the operation of the gear lever stiff.
Like anything else close to dust, the gearbox suffers from ingress of dust over time and whilst this isn’t a major cause of noise it nevertheless
doesn’t help with the operation. Here is my solution:
To gain access to the gearbox firstly isolate the power supply.
Undo the securing screws of the cover and put them somewhere safe.
Swing the head stock away from you so that the gearbox faces you.
You will be confronted by the belt and the pullies. Firstly, vacuum out the gearbox and cover. I strongly recommend the wearing of a face mask at
this point and also disposable gloves.
I foolishly removed the belt from the drive/motor end and the plates, under spring tension, snapped shut. Oh no! Initial panic but a few words with
the Axminster Tech team put me right. The pulley plates on the drive shaft were ingrained with dust and therefore their removal was needed to
give the drive end a good clean. To remove them I needed circlip pliers. After all my years, the one tool I didn’t possess was circlip pliers but these
were easily obtainable from the internet. To continue.
5. Grasping the spring on the shaft remove the circlip and place it somewhere safe. The plates on my lathe had closed and therefore there was no
energy in the spring. If the belt is in place the energy presented is present but minimal. Remove spring, retaining washer and nearest plate. Undo
the grub screws holding the back plate onto the shaft, remove the plate.
6. Give the plates and the shaft a good clean. The shaft may require some attention using a 400grit abrasive, or finer, or wire wool to remove any
residual gunk on the shaft.
7. Lubricate the shaft. I used silicone fluid.
8. Whilst the shaft is bare, access to the variomatic shaft (the shaft that drives the live end) is made easier. I made no attempt to remove the pullies
here but cleaned up as best I could in situ. By operating the lever to a high speed position the plates will open up thereby allowing you to apply
some lubrication to the shaft and bearings of the variomatic device situated between the plates and the fixed live end bearing. Ensure that all grub
screws in this area are tight.
9. Replace the drive end back plate to a circlip situated on the shaft close to the motor housing. Tighten the grub screws so that they bight into the
shaft and not the keyway on the shaft. Now comes the tricky bit. Replace the second plate, but do not try to fit the belt at this juncture as you will
never get the circlip back onto the shaft unless you have a gorilla as an assistant. The plates will close together but don’t worry. Return the spring,
retaining washer and circlip.
10. Place the drive belt on the variomatic pulley first and then manipulate the pully over the drive end plates. The belt will be tight but you can get it
to sit on the plates. With your thumbs on the circlip end of the shaft and your fingers and fingernails pull the plates apart so that the belt starts to
enter the gap between the plates. Now put pressure on the belt and it should begin to slide between the plates.
11. If you are lucky enough to have a set of bearing extractors these will probably do the trick however the plates are made of alloy and any undue
force will crack the plates. Seek advice from Axminster first.
12. Taking great care with the cover off, reconnect the power supply and give the lathe a test spin. Operate the speed changes. This is a good
opportunity to observe how this clever piece of kit works.
13. Remove the power supply again and check the grub screws around the operating lever are tight. Being curious I undid and removed mine. The
operation is a simple rack and pinion movement on a square threaded shaft and it transpired that this was where most of the noise was coming
from because of loose grub screws. I replaced the lever and tightened up. (Note: There is a certain amount of backlash between rack and pinion as
it is very basic system)
14. Replace the gearbox cover with the screws, if you haven’t lost them on the workshop floor.
Return the head stock to the datum position, replace the power supply and test run.
Mine now runs like new with a smooth, quiet lever operation and didn’t realise just how bad it had become before I had carried out this