New single phase motor problems.

[bigbadbugga]

I have bought a new 1hp 240v motor and reverse switch for my Boxford lathe.

I just have a few small problems that I would like to run by you guys if that is ok

Firstly, the old motor spindle is 16mm (actually a bit bigger so I assume an imperial size) with a woodruff key. The new motor has come with a 19mm spindle with a woodruff key.
I have been in touch with a company who can re-bore my pulley to 19mm, but they say they can't re-cut the slot for the woodruff key, and suggested putting a flat on the motor spindle and using the grub screw alone to lock it in place.
Will this be ok?
Also, I have a pillar drill, is there anything stopping me from drilling the pulley out myself?

Secondly, the base of my old motor is fitted with slotted mountings to allow the belt to be tensioned, these can not be swapped over as the mounting points on the motor are different.
I think I can make an adapter plate myself, or are there different mounting bases available from anywhere?

The Lathe is an early 1960's Boxford csb lathe with the drive bolted behind the headstock.

 

[the snooper]

if you can guarantee to bore the pulley central then do it, you can also cut the key way yourself

 

[gordon stephenson]

Best thing for you in my opinion is to get the pulley bored by the firm you mentioned and make the keyway yourself using hacksaw and files to get the size right, with an alloy pulley it won't take long at all,just take your time and keep checking frequently,

 

[bigbadbugga]

I'm thinking along the lines of.

1. fit the pillar drill with a 16mm bit.

2. put pulley on the drill table and lower the drill through the hole.

3. clamp the pulley tightly down and lock the table.

4. change drill bit for a 19mm (or whatever size is needed for tight slide fit)

5. drill the pulley (it is aluminium)

I'm not really bothered about the woodruff key if I can use the grub screw to hold it, I was thinking of using a larger grub screw and screwing it down into the woodruff slot in the spindle to lock it.

 

[bigbadbugga]

Best thing for you in my opinion is to get the pulley bored by the firm you mentioned and make the keyway yourself using hacksaw and files to get the size right, with an alloy pulley it won't take long at all,just take your time and keep checking frequently,

Thanks, I may still do this as they only want £7 to bore it out. the cost is not a problem but I am not the most patient person alive, so if I can do it myself in a morning rather than posting it off and it taking a week I tend to take the quickest option.

 

[shenion]

I take it the lathe is not functional without the motor?

I have bored pulleys on a lathe with no problem. I have also cut Woodruf key slots. It can be done with a parting tool:

The lathe does not need to run to cut the slot. I used a custom ground tool and advanced the carriage about 0.002" each pass. Slow, but it works

 

[gordon stephenson]

Do not drill out the pulley as you have described, drilling with a 19mm drill will give you an oversize hole and the fit will be slack on the motor shaft,

 

[stormin]

Have you considered a taperlock bush?
No need to bore a taper as you can get an adaptor sleeve. It would then be an easy job to drill out the bore on your pulley yourself.

http://www.bearingshopuk.co.uk/1210-19mmtaperlock-bush-5191-p.asp

http://www.powertransmissiononline.co.uk/ProductSearch.aspx?Task=Search&Category=71

 

[gordon stephenson]

Hello stormin,
If he did buy a taperlock there would be no work required, he would just buy the correct size complete with pulley to start with. if any boring was needed he would still be in the same position he's in now, Don't know the cost of a taperlock but they won't be cheap,but some of this cost would be off-set against not needing the boring doing to the original pulley.
Taperlock pulleys and bushes are great, used them thousands of times, very easy to fit/remove.line-up etc,

 

[brightspark]

machine mart do pulleys 19 mm bore up to 6inch there a section .or as gordon says get a taperlock pulley it will fit strait on there not expensive mind u your lathe may be b section belt on motor ?

 

[bigbadbugga]

Thanks for the input guys.

I think I'll send the b****r off to be bored and get the job done properly, I can't get a MM pulley as it needs to be a double pulley to change speeds on the lathe.

Shenion, thanks for that tip on cutting the keyway, I will most likely do it that way

 

[gavuk]

I've had to cut keyway as Shenion described its quite slow ,but works well,remember to select lowest gear or stop the chuck from moving ...have also drilled pulley and motor and used taper or roll pin to drive,also fitted a shear pins,surely there must be a local firm who can bore and key the pulley ?.good luck Gav

nb. drill and ream the pulley would be ok too......

 

[stormin]

Hello stormin,
If he did buy a taperlock there would be no work required, he would just buy the correct size complete with pulley to start with. if any boring was needed he would still be in the same position he's in now, Don't know the cost of a taperlock but they won't be cheap,but some of this cost would be off-set against not needing the boring doing to the original pulley.
Taperlock pulleys and bushes are great, used them thousands of times, very easy to fit/remove.line-up etc,

If you've used taperlocks thusands of times I thought you'd know they're cheap as chips, approx £2.50-£5.00, the adaptors for parallel bores are slightly dearer.

Still a whole lot cheaper than buying a new pulley, especially a double one.

 

[gordon stephenson]

Hello stormin,
Despite having used tons of these items, always being employed by multi-national companies I have never had to buy any, just tell the requisition people what you want and how many,and they appear as if by magic. Anything at all, if you need it you get it no questions asked, Comes as a big shock when you retire and find out how much things cost in the real world when your stocks run out.