Boxford Lathe wiring advice

[bigbadbugga]

Hi guys, I finally got myself a lathe.

It is a Boxford CSB of 1961 vintage and in fairly good condition.

It has been fitted with a 240v single phase motor by the previous owner, however all he has done is fitted a 13A plug direct to the motor, he said he just plugged it in and used the switch on the wall socket to turn it on and off.

So I really want to wire it up a bit better, with a red and green start/stop panel and an emergency stop plunger.

Do I really need a forward/reverse switch? the machine has tumbler reverse.

can anyone direct me to some sort of wiring schematic? (my nephew who is a qualified sparky will be doing the work)

thanx in advance

(I'll put some pics up tomorrow when I have a little more time)

 

[m1ecy]

Electrical reverse is unlikely to work without a three phase motor - if Nephew is a sparky he will not need a diagram to wire in an external starter box - they are very simple - supply in, and motor feed out.....

Sean

 

[shenion]

Check the motor, it may have a diagram on how to reverse it and the connections; many do. IF so, a drum switch can be used.

Reverse is nice to have, but you can often live without it. On my Atlast/Craftsman, to cut metric threads you can not release the half nuts or tumblers. So you need to do a pass, retract the cutter and run the lathe in reverse.

 

[rtbcomp]

The wiring diagram on three of my motors is on the reverse of the panel that covers the connections.

If not, stick a photo up one here of the connections under the plate, someone may have the same motor.

 

[gordon stephenson]

Hello bigbadbugga,
I believe the reverse switch will only have worked with the 3 phase motor, the tumbler reverse you speak of is only to reverse the direction of feed/lead screw, the chuck will still turn in it's original direction i;e anti clockwise veiwed from the tailstock end.

 

[MrFluffy]

Check the motor, it may have a diagram on how to reverse it and the connections; many do. IF so, a drum switch can be used.

Reverse is nice to have, but you can often live without it. On my Atlast/Craftsman, to cut metric threads you can not release the half nuts or tumblers. So you need to do a pass, retract the cutter and run the lathe in reverse.

If you have only got forward gear, you can come to the end of the thread, disengage the motor clutch leaving the leadscrew etc engaged still, and then wind the chuck backwards by hand back to the start which will also turn the leadscrew back keeping it indexed to the chuck position. Its a ballache, but it makes things do-able at 2am when otherwise you couldnt.
My harrison is currently like this, and Ive used the above method with sucess.

 

[hareng]

You will find it very useful having a reverse especially when threading or opposite to normal boring ie cuts on the right of the hole bored.

Many old machines have forward and reverse fitted as standard. My old ML7 scrapped 10 years ago and current 1965 Harrison 140 both have it fitted as standard and original.
Harrison runs from a 13 amp plug to an isolator and then in turn to a lever Forward Off Reverse Off and a main motor start push button. Knock the lever out to off, relay trips out motor stops eventually. Have to wait for motor to stop before it can be powered up for reverse else it carries on in same direction regardless whether forward or reverse. Always planned on changing this sequence, nice to be able to move lever to off or reverse without starting motor again like Colchester Triumphs.

A good sparky will figure it out and sort the switching contacts along with the motor wiring, did it twice on Myford.
The ****** motors are real easy, just turn 90 degrees a shorting strip to change direction, remove it and wire to a switch.
Prefer the lever types of switches on lathes rather than the magnetic types and vice versa for millers.

You can get this type of switching
http://www.lathes.co.uk/advertphoto/090610super7bpower/ Far left of piccy. http://www.lathes.co.uk/advertphoto/090610super7bgray/
http://www.gandmtools.co.uk/cat_leaf.php?id=6065

 

[bigbadbugga]

There is a forward/reverse switch on the machine, but it is part of the 3 phase switching and has been disconnected.

can I still use this just rewired for 240v?

will take some pics of it all in the morning.

 

[hareng]

Well i am no sparky but a switch is a switch and would need figuring out as to what contacts do what. Multimeter needed.
From memory 4 wires from motor or 3 if bridging two common contacts. One would be forward, one reverse the other/s return to create the loop.
Need to figure the switching for the power in and distribution, again if he is a sparky its easy.

Get sparky to check whether motor will run in the other direction, i have an oldy 3hp on pedestal polisher that cant be changed. If not nip to machine mart and get a ****** motor.

 

[wyn]

I fitted a machine mart motor and reversing NVR switch on my lathe. from what i remember it was pretty straight forward to wire up. The reverse does come in handy now and again. As hareng says there were 4 wires to the motor + earth and chuck away the link bars on the motor connections

 

[bigbadbugga]

Thanx for the advice so far guys, here are some pics as promised.

The lathe, its a CSB, based on a model 'C' backdrive lathe but with a short bed (18'' I think). It has the extra pulleys to extend the CSB's range of speeds.

 

[bigbadbugga]

Here are the switches I have.

Here are the innards of the direction switch, they look quite servicable to my untrained eyes.

Here is the inside of the on/off switch, now I'm no expert but I think something is missing

This is inside the main switch, it says there is a feed for 12.5/25v, I assume this is for the lamp.

I'm thinking along the lines of getting a new on/off switch with emergency stop plunger and utilising the existing direction switch (providing the motor is capable, will investegate later)

anyone got any opinions based on what you see above?

thanx guys, I really appreciate the input

 

[bigbadbugga]

Here are the motor pics, it looks like I'm in luck as there are instructions for reversing the motor on the terminal cover plate

 

[wyn]

I'm thinking along the lines of getting a new on/off switch with emergency stop plunger and utilising the existing direction switch (providing the motor is capable, will investegate later)

That sounds like a good plan, and hopefully the wiring should be straightforward.

It would be a shame to ditch the direction switch.

 

[Pete.]

Yes that motor will reverse easily. Whether you can do it with the reversing drum switch you have depends on how the switch is wired up bu tit looks good from here. You'll have to run a tester over it and see what connects with what at the three switch positions, and you'll have to run wires out of the motor to the drum switch and back to the motor, separate from the power feed wires to the motor.

If you want to wire-up safetys you'll need a 240V contactor to do it right. The green button should have a non-latching contact to pull the main contactor in and the red will have a normally-on contact to break the pull-in circuit and release the main contactor. Looks like the guts of the button-box are missing.

 

[MrFluffy]

The innards are missing from your on off switch. There should be a springing contactor mechanism that the non latching itself green button pushes into latching, and the red button when pressed releases the latch mechanism on the contactor. Another function it has, is when the motor is overloaded, the latch mechanism overheats and throws out the contactor too as a additional safety mechanism.
My guess is it was gutted when someone did the single phase conversion on the lathe...
You can probably adapt one from any similar rated motor powered machinery, a drill press/lathe/big compresor/mill or anything really.

 

[shenion]

The best option is to get a variable frequency drive (inverter or VFD) and a 3-phase motor.

My lathe had a 1/3 HP single-phase motor that had decaying, cloth-covered wiring. On, ebay, everyone with a mill, lathe, drill press, table saw wants a single phase motor, so they don't go cheap.

I picked up a 1/2HP 3-phase motor and VFD for about $100. CHeaper than getting a replacement motor. Also gives you variable speed, controlled ramp up/down and fault handling.

That motor can work with a reversing drum switch. You will need to bring all 4 wires (those that connect to A1 and A2) to an external box. You can use two switches, one for fwd/rev and another for on/off.

 

[hareng]

Certainly looks like original equipment including the motor, incidently as used on the ML7 Myford 1/3hp. Well underpowered you wont do a thing with it unless in back gear.
Buy a 1hp ****** from Machine Mart if shaft same size http://www.machinemart.co.uk/shop/product/details/1hp-single-phase-4-pole-motor Cap start as well use one on the smaller mill.

I would do away with that starter, rightly or wrongly it will drive you mad. Select forward or reverse then hit starter every time, Myfords didnt have it more a thing that Harrison used to do. There are times when a quick blip on the direction switch will rotate spindle sufficiently when centring something removed from chuck and put back in.
There again i used a Brook Crompton 1hp on the ML7 i had and had to bore out the pulley to take the bigger shaft.

 

[eil]

Or one of these, ive had a couple off this chap they have been fine.
http://cgi.ebay.co.uk/Electric-Moto...sors?hash=item518bd4e1aa&_trksid=p3286.c0.m14

 

[hareng]

Thats almost identical to the Machine Mart one on my small miller and same price delivered. Cap box the same as is the casings and tapped holes, the fan guard is different.
Shouldnt go wrong on either mines has had several hundreds of hours continuous use. Very easy to configure and understand what wires are necessary, to For Rev switch, done on Clark Mill/drill beats paying £260 for new motor.