It pays to talk - proud owner of a Box-ford Model "A" Lathe

[kwackers]

If the load isn't roughly equal on the idle pulley - i.e. one belt is pulling it harder than the other then you'll have problems. They don't need to be exact, usually I slacken off the idle pulley, run the motor for a second or so then tighten it up. On some machines the idle pulley floats to allow it to move around.

Another thing to check is that the pulley is a reasonable fit on the shaft. If there's too much lateral play (i.e it's worn) then it'll try to tilt which will produce lots of friction at a couple of points. If so then you'll need to sleeve the pulley and/or change the shaft.

[RichardShute]

I had an issue tonight and was hoping someone could help. I had my lathe running for about 5 minutes and randomly touched the pully shaft bushes, the hole area around where the pully shaft was mounted was really hot - too hot to touch. Is this right??

Chris

If it's too hot to touch it's definitely not right. Personally I'd be inclined to try to get a slightly longer belt rather than drilling new holes, seems a bit of a shame. Secondly, you also comment about 'greasing' the bearings, are they plain bushes or ball bearings?

I have a S&B Sabel which, like yours, is a development of a Southbend and it uses a countershaft very similar to the original, fitted with bronze bushes. These are oil lubricated, not grease, despite the fact that they have what look like grease nipples. I can't imagine ball bearings could possibly get so hot so I assume you must have bushes; check the lubrication chart in the book, I'd expect oil, probably the ubiquitous ISO32 hydraulic. Mine get 'detectably warm' after half an hour or so.

Richard

[raynerd]

Hi, sorry, I never replied but I fixed the issue with the temperature of my pully shaft - the belts were too tight caused by the position of the new  3 phase motor. Was probably just a few mm lower than the original. I have slipped under a shim and bolted it down tight and that has taken off some of the tension and now all seems fine.

I have a question. I have a little money, infact I`d just put it aside for the ME show later in the month but I`m considering spending it on an ER32 adaptor for my Boxford.

RDG do one for £60
http://cgi.ebay.co.uk/RDGTOOLS-ER32-COLLET-CHUCK-BOXFORD-LATHE-/370424484694?pt=UK_Home_Garden_PowerTools_SM&hash=item563f051356

Chronos do one for £50
http://www.chronos.ltd.uk/cgi-local/sh000001.pl?REFPAGE=http%3a%2f%2fwww%2echronos%2eltd%2euk%2f&WD=boxford&PN=Soba_ER_Spring_Collets_Systems_%2d_NEW__%2ehtml%23a288251#a288251


I`m not sure if they are identical or rebranded but have you any suggestions as to which would be of a better quality? I`m also guessing this is a subjective question but do you think this would be a useful addition to the lathe. I have a good selection of chucks but considering I have an ER32 collet set that I use on the X2 mill, I thought I`d get more use out of them and also would hold the work piece more securely using a collet set, especially for smaller stuff.

Any thoughts or opinions welcome before I spend my cash.

[Bluechip]

Chris

If it's relevant, I have a SOBA ER25 collet chuck, Myford fitting, from Chronos, and it's fine.

With Vertex collets, get about .0005"  ish runout, near the chuck. Some a couple of tenths better, some ditto worse. Worst about .0007" IIRC
Some times clocks more some 2" away, but I have no means of checking how straight bar stock is ! I don't believe it's perfect  

Dave BC

[raynerd]

Do you use yours a lot?

I`m just trying to work out if it will benefit me...I currently hold work in one of my chucks, do I need to spend £50 to hold it in a collet?

[Bluechip]

Chris

Depends .. use it mainly for small bar up to 8mm or so. Bigger than that, it's the chuck , usually.

My main use is for threading stuff like M3 M4 M5, where the eccenticity of the chuck makes threads too deep.

Hard to say, sometimes it's on the Myford for days, never put the 3-jaw on .. then don't use it at all for weeks ..

Nice to have though, unless you have an impeccable SC chuck   .. mine ain't  

Dave BC

[NickG]

Chris,

I have ER25 for my milling machine but I have on occasions used it in my lathe headstock for holding tiny stuff. Only problem is it sticks down quite far from the mill so sometimes I think using finger collets would be more rigid.

My 3 jaw is pretty good now but as Dave BC said I don't think it could do stuff like threads on small parts.

What do you currently use on the mill?

Nick

[raynerd]

Thanks for the reply guys. I use an ER32 collect set on my mill which is why I`m considering getting the chuck for the boxford so I can use it on that as well.

[NickG]

Sorry Chris, I didn't read your post fully and click the links, I just used my milling chuck in the lathe but obviously you can't grip long lengths that way.

I've seen different types of collet chucks cheaper than that if you have a back plate, so you skim the back plate down in the usual way you do when mounthing a chuck and bolt it on.

Can't remember where though, possibly arc eurotrade - will have a look.

Nick

[raynerd]

Nick, yes I do have a backplate. Arc Euro sell their ER32 collet for backplate mounting for £35.

I`m quite embarassed to say that I`ve never used a backplate!!!! My boxford has a threaded spindle so all my chucks just screw on and off. That being said, my lathe did come with a backplate with Boxford thread so I do have one - wouldn`t know to

" skim the back plate down in the usual way you do when mounthing a chuck "

as I`ve never mounted one. I was reading somewhere that this is more accurate way than using one of the RDG or Chronos Boxford threaded ER32 chucks, but I`m not sure why and can`t for the life of me find the thread again.

I have decided that I do like one but it is know which one to get!? A Boxford threaded or backplate mounting.

Chris

[AdeV]

As I understand it, most (presumably non-OEM) chucks come without any particular fitting; the idea is you buy a part-machined backplate (or make your own) which is simply a disc which fits to your lathe; you then skim & turn this such that the chuck "just" fits onto it, and I guess drill & tap to attach chuck to backplate.

At least - if I look at the back of the various chucks I have, the all have a separate piece which is the lathe fitting. e.g. the one I acquired most recently has some kind of threaded end - this can be removed from the back of the chuck & a new backplate made.

[Bluechip]

I was reading somewhere that this is more accurate way than using one of the RDG or Chronos Boxford threaded ER32 chucks, but I`m not sure why and can`t for the life of me find the thread again.

I have decided that I do like one but it is know which one to get!? A Boxford threaded or backplate mounting.

Chris

Chris

I cannot see any reason why a backplate would be more accurate.

A backplate is located radially by the accuracy of the register on the backplate, as is a direct mounting collet chuck. Same mechanism.

Or is there some other reason? I know it's possible to tweak a SC chuck by undersizing the chuck register, and tapping the chuck  to clock true  before winding the bolts tight. But I don't think it's recommended.

Dave BC

[NickG]

Chris,

Just because you're machining that register on the actual machine it's going to be used on, you're making the register with zero run out, where as the of the shelf jobbie has been machined on some other machine with its inherant run out, then when you put it on yours it will be compounded. To be honest, they should be fairly accurate but that would be the theory behind it. If you've got a backplate, you could save a few quid and get that one.

I made a thread of when I mounted my new 3 jaw chuck here:

http://madmodder.net/index.php?topic=1303.0

same principle.

Nick

[raynerd]

OK Cheers guys. Like AdeV suggested, I found the thread: http://www.rcgroups.com/forums/showthread.php?t=636594

This assumes that your thread and register is also accurate on a worn machine.
If for some reason it doesn't fit the register snugly then it will throw the ER collet
bit off and unlike a backplate that you skim for accuracy on the host lathe you are stuck.

However further in the thread a few of them have both (why I don`t know!) and it seems that the run out on the threaded ones are good. Hummm...I`ll have a think.

Chris