Couple of lathe spec questions

Hi I am looking at buying a new lathe. I have had the clarkecl500m for a few years now and although it has been great I really need something with more features and ease of use. I am looking at the Chester DB10 super lathe (and other manufacturers selling the same spec under different branding). I have a couple of questions.

1. The option at Chester is for an open or closed gear box, truth is I don`t know what the difference is can somebody help me out here? On the clarkecl500m you need to manually install the change gears to cut a desired thread. This wouldnt be so bad but it messes up the auto feed rate so after cutting the thread you need to change them back again if you want to do some normal turning using auto feed. (big pain in the ass). What effect on screw cutting procedure does the open or closed gearbox make?

2. The lathe can be purchased in two flavours one is Belt driven (only shows this version on ebay chester tools shop) and the other is variable speed motor. I have a mill with a variable speed motor which the rpm readout died on it not long after purchasing it. It still runs fine and I am ok setting the speed by feel so to speak but electronics always worry me with the extra problems that can come with them. Would I lose any features by buying the Belt drive version ? (I dont mind having to change the belts I do that now on the clarke)

any help appreciated,

Ady.

These are specific questions regarding a Chester Lathe, so why not just phone them and ask. I'm sure if you want to buy one of their machines they would be only to happy to help.

Tip:The ebay prices are often more expensive than buying direct they normally add the cost of any fees to the price quoted

Looked at the Chester site.

Open gearbox is a proper "Norton" type with cone of gears and tumbler selection. Ought to have a wider range of threads and feed available, 9 on the Norton box multiplied by how ever many input (or output) gear ratio selections there are. Old style industrial lathes tend to have 3 or 4 input gear ratio variations selected by another lever as well as an overall threading / feed selection. However looking at the web-site picture there doesn't appear to be an extra set of selectable gear ratios or even a threading / feed selector lever.

Closed gearbox is appears to be two 3 speed gearboxes in series giving 9 selections. Again I can't see if there are any an extra set of selectable gear ratios or even a threading / feed selector lever.

So the two machines may well be exactly equivalent with 9 threading or feed selection changes on the machine controls with extra change gears included to extend the number of variations. Seems to be no reason for the two variations. However closed gearbox style with DC drive is the common version of this style of machine so maybe the open gearbox goes with the open belt drive version from a different maker.

Website says the beast is not up to continuous industrial style use. So the motor and / or DC drive is liable to get too hot if used for too long. Its unlikely to have full on overload protection or even some guidance as to how hard you can work it for how long. Best to assume the motor or drive will eventually overheat and blow up if you put it to serious use. Eventually being impossible to define in practice. With a belt drive if the motor does go its not going to be impossible to graft something else on. Probably need an external countershaft but its do-able.

As always the supplier has taken their best guess at a price / performance / capability equation that adds up to something attractive, affordable and useable. Down at this end of the market there will always be some fairly serious compromises so when deciding what to buy you have to be very sure that the compromises are mostly outside what you intend to do. Given that any half decent lathe can be expected to last for many, many years I'd go for the open belt version as if the motor or drive does go down 10 years in the future and spares are unobtanium you will be able to do something about it relatively easily.

Clive.

Edited By Clive Foster on 16/10/2017 11:56:59

In my experience this is more to do with the extra liabilities of selling to industry = greater costs to the seller, so they do this to keep the price down.

One place I worked all our power tools bought by our team were Makita etc. as we had to use 'trade' rated items, The guy who bought them used cheaper versions at home and said that in practice they worked just as well but couldn't cope with being dropped/mistreated by apprentices/volunteers etc.

Neil

The belt drive version uses a standard induction motor as opposed to the variable speed dc drive using a dc motor and a KB or Chinese clone thyristor based speed controller.....( the dc drive based version has history of failing in service...either down to controller failure or the motor overheating due to lack of cooling)

I have the Chester 9 x 20, has a Norton style gearbox and seperate change wheels for threading/feeding....it is also belt driven, but mine has a 3 ph motor with vfd....Has been a great machine for me....

Thanks for the replies guys much appreciated.

Have just ordered the open gearbox version now.

Probably the better option. I couldn't see the details of the closed box but a lot of these lathes at the moment with a not-Norton style seem to be a half baked attempt at covering some metric ratios with one lever and some imperial with the other so you end up with only a couple of selections without changing the gears. Perhaps you can put a mini review on here with more of the details when you get it.

Yeah will do a review in the near future when have had chance to have a play with it. Machine is being delivered on friday so am having day off work. Hopefully it will come in morning which will give me chance to try and get it mounted to the bench. Should get a few hours on it over the weekend.