|Started August 2003||
Chinese Lathe Page
Drive Belt Issue
The low range toothed drive belt snapped at the end of October and getting a replacement has been challenging to say the least. The belt is totally non-standard and at 3/16" pitch totally unique to the lathe and is I believe what was called an F-Series belt. This pitch of belt was obsolete in the 1960's.
Anyway Chester sent me one in the post for £20.50 which was too short i.e. a 118 tooth belt instead of the 124 tooth one fitted so way too short. Their invoice even said it was 124 teeth but after counting them and laying the belts against each other it obviously wasn't.
Sent the belt back and eventually recieved a used replacement they managed to find and have placed a request for a further spare (just in case) on back order but hold little hope of getting one any time soon..
Bear this in mind when ordering a lathe as replacing the pulleys and belts with QUALITY ones from HPC Gears will set you back over £100 plus vat, although once you have done this you can get better quality belts off the shelf from anywhere.
If I get no joy from Chester I will post the part numbers, you will have to bore them out to suit though at over 600 rpm if you havent got access to another lathe though!
The creatively frustrated one, decided in 2003 to purchase a small lathe, that decision was easy enough, the difficult bit was then deciding which lathe would best suit his needs, available space and depth of pockets. Much research was conducted via the web and learned colleagues on the subject and some interesting observations were made.
On the web it appeared that the Chinese lathes had a pretty bad name whilst old British lathes were the most desirable items, this too seemed to be the opinion elsewhere. With these two facts in mind I then tried to narrow the field down by deciding on what size of lathe would be best and soon came to the conclusion that a 4.5"/5"x18" lathe would be about the optimum size. In the second hand market two lathes stood out as probably the best, a Myford ML7 or a Boxford. Myfords are very nice but very expensive so the Boxford was to be the subject of the final search. Having hunted for a suitable example (ebay was the best place) I rapidly came to the conclusion that a screw cutting Boxford (BUD or CUD) in average condition with a three phase motor and a three jaw chuck commands a price of approximately £700. Add on another £100 to convert it to single phase, plus another £100 for a four jaw chuck, another £60 for a face plate, another £80 for a pallet delivery and we have already crossed the grand mark. All that for a lathe that will be at least 20 years old, may have been previously abused somewhat and will probably need a considerable amount of work to get in order.
Now a friend who lives locally has a number of old motorbikes and in order to keep these bikes in tip top shape he has a lathe. His lathe is a Warco (Chinese) 918, this lathe is certainly nice enough and has a similar capacity to a Boxford. This type of lathe is sold (marketed) under lots of different names depending on where you live and Chinese / Taiwanese lathes of many different sizes and prices are available from countless retail outlets as well.
So having given up the hunt for a used lathe as a potentially expensive mistake I scoured ebay for a used Chinese lathe fully expecting to find loads of then available second hand, as everyone who ever bought one would surely realise their mistake and flog them after 12 months or so to fund the purchase of a Myford. Now here's the interesting bit, there's no second hand Chinese lathes to be had on ebay. This to me inferred that more or less everyone who had bought one was happy with their purchase.
So I said 'sod it' to myself and decided to try one for myself.
Chester UK are only around the corner from the creatively frustrated ones residence, so as I can drop in on their showroom rather than Warco's I decided to check out the goods in person. Having checked out the machines on offer I plumped for the DB10G as the most suitable as it offered slighlty larger capacity than the 918 and according to Chester's Anthony is hand assembled in smaller batches of 10 units rather than coming off a production line, and would come with an accuracy certificate.
The beauty of these lathes (918 et al) is that they are all small enough (and light enough) to mount on a bench or steel cabinet. Rather than spend a £150 on a stand of Chinese origin I plumped for a £5 second hand British made steel cabinet from an engineering firm who's manufacturing arm was going 'tits-up'.
After cleaning off all the grease the first impressions are very good, though bear in mind this is the big brother (10x22) of all the small Chinese lathes from the 7x10 mini lathe to the 9x18 (918). The actual lathe itself from the quality of the castings, the bedways, handwheels and markings through to the tool post, chuck and paint finish are all very good.
Under power the lathe is extremely quite even on its 'tin plate' noise amplifying stand. All the hand controls are more robust and better made than the typical 918 and have a positive feel to them. The belt change however is a bit of a bastard as on the low range 100-400 RPM the belt is a little slack so the tensioner is doing a lot of work (though easy to adjust). Whereas on the higher speed range where the transfer pulley is not used i.e. the belt runs directly between the motor and the headstock it is that tight you don't need to use the tensioner which makes speed changing a potential finger trapping and pulley damaging experience.
The solution is to simply buy a second slightly longer belt, as the belt is a 10x6 Z type Vee-Belt it is the same as the type of alternator belt fitted to older cars so a suitable replacement is no further than your local supplier of car spares.
To quickly check the accuracy of the bed/headstock alignment I decided that an easy test would be to turn down a short 150mm length of 2" sch40 stainless steel tube by a small amount in the 3 jaw chuck then reverse it without adjusting the saddle cross slide and complete the operation to its centre point. Any misalignment would then be visible on the workpiece.
Straight out of the crate from the other side of the world 3 months from its date of manufacture I expected that there would be some misalignment. However, the degree of misalignment is so small as to be virtually indiscernible except by touch on the test piece with only one point on its diameter at the central junction having the tiniest lip <0.01mm max over 60 degrees of the circumference at a constant diameter of 47.125mm.
Speeds & Feeds
Now for those little things that need changing (end user modifications).
The Lathe did not come with an Accuracy certificate!
The manual is hilarious, and has quite obviously not been proof-read in the UK and the engineering drawings of the machine are quite obviously hand drawn and a little fuzzy in their reproduction, though they do carry all the relevant information.
(7.12.05) Jacques Reumont has written a page in french on the DB10G it can be seen here.
(16.01.04) Chester are currently Re-Writing the manual for the DB10G and all new lathes will shortly be dispatched complete with the new version.
(29-10-10) First component failure the toothed drive belt to the intermediate pulley for the lower speed range has resulted in an interesting observation and problem. The 3/16" (4.7mm) pitch of the teeth is totally non-standard and is believed to be what was commonly known as an F-profile belt, a profile that was rendered obsolete in the 1960's. The only belts available from the supplier or not of great quality hence snapped belts may be a regular problem for the future.
All newer DB10's are now equipped with cheaper to manufacture variable speed motor drives as per most modern smaller lathes and milling machines. The belt issue is accordingly only an issue for older lathes.