Repairing an AWBL1200 Wood Lathe

[timhitchcock]

Hi, I am knew to this forum, but wondered if anyone can help me? I have had an Axminster AWBL1200 Lathe for the last three or four years - recieving regular hobby use. Although the lathe gets up to full speed with no difficulty, it has recently begun to cut out under the lightest cut - essentially, stopping and restarting. This is not a full break - as I don't need to switch it back on, for it to restart. This has recently gone from an irritating foible to an unworkable situation.

I have been on to Axminster technical support, and they have suggested either that the 'motor has lost torque' and will need replacing at some £300, or else that it is a problem with the printed circuit board, and I should get an electrical engineer to look at it. Not being able to find a local repair shop (I live in the land of bespoke Italian bread and endless clothes shops), and given the money involved, I now don't know what to replace or how best to test for what has gone wrong. The bearings seem fine, and the motor does not overheat.

Any advice on how best to proceed, or on a reliable repair shop in North London, very much appreciated.

 

[chipmunk]

Hi Tim,
I think as a first step I'd try to get at each and every wiring connection you can and look for a bad connection. If there is a problem you may see some charring and blackening but equally you may not.

From what you say it sounds to me as if the extra current being drawn when a cut is made is causing too big a voltage drop across a bad connection somewhere in a high current path to the motor, causing it to cut out.

You may have to dismantle things to get at these connections but if you're careful and do things methodically you should be able to put things back as you found them. Just unplug/unscrew and reseat all of the connections you can get at - perhaps doing it a couple of times with plugs/sockets to wipe the surfaces of the contacts to remove tarnish that may be there.

It's also possible that there may be a snapped wire near to a crimp on connector. You can often feel these by more than normal flexibility near to the connector and the insulation may be "wasted".

If this doesn't work and you can find the PCB that Axminster are referring too then I'd take a look at the solder joints on the back of it and look carefully for one or more dull looking joints (dry joint) or perhaps a joint with a crack through it. It'll be a pretty high current track by the sound of things so it should be one of the bigger joints.

If you find a dry or cracked joint and you have a soldering iron then you can touch it up very easily. With a hot iron, clean the tip on a wet cloth or sponge and with a length of solder, whet the end of the soldering iron with a small ammount of the fresh solder. Hold the whetted iron to the joint, remelt the joint and add a very small ammount of fresh solder to the joint and then remove the iron. It should be the work of at most 2-3 seconds and provided it remains still while cooling the joint will be bright and shiny again indicating a "good" joint. Provided you don't use too much heat or add too much solder you'll do no harm. Be careful not to bridge any tracks with too much solder.

Failing that then you may have to contact Axminster to get them to fix it. You should be able to send then just the headstock assembly for repair.

Good luck and HTH
Jon

 

[Martin10]

A can of contact cleaner from Maplins may help too.

If the circuit board is damaged, and you don't have a soldering iron, I may be able to help. I work in Hendon, North London, so not that far away, and I have electronics labs where we have decent facilities.

Martin

 

[timhitchcock]

Dear Jon and Martin, Both your responses are very much appreciated and a great help. I can't get into my workshop for a few days (travelling) but will hope to have a go next week, and will let you know how I get on. I have always wanted to get stuck in to a bit of soldiering, and this sounds like my opportunity. Thanks! Tim

 

[Richard@Axminster]

Good afternoon,

Sorry for my late reply, I was away last week! I have passed this on to our workshop to see if they can come up with a solution.

Leave it with me....