thin king

While in operation in October 2017 the drive belt in my lathe broke; it was shredded due to wear and tear. Alarm engulfed me. How was I to find a replacement belt; getting the lathe itself was one long search. Nobody sells such lathe in Singapore, and nobody sells one to Singapore, not even the manufacturers in China. It was a hobbyist model, and there was no woodturning hobbyist here yet.  Finally I got it in April 2014 after posting on the WWW. Harbor Freight in the US offered a sale and delivered this Central Machinery lathe which like most lathes of this kind were made in China.

The belt was tattered, no part number can be seen, so how was I to tell people what belt I want. I carefully determined its dimensions, width, thickness, cross section, number of ribs, teeth, circumference and type of material. Hopefully with these details I could quote my belt as I could not find any other detail on the broken belt. It occurred to me that it would be futile looking for one in Singapore where no such machine has need of it. There are belt shops around, but mostly they cater to the autocar industry. My queries to people I know received no response. I was the only woodturner and this problem was uniquely mine.

Amazon and Ebay were useless, they offered all kinds of belt, but nothing near to what I needed. One road one belt was not around then, ha ha. My best bet was Aliexpress, the home which manufactures billions of things, and it was a China product I needed. Aha, myriads of belts were on sale, but not one near to my requirements. Finally I found one with the same type of ribs and cross groves, but it was not of the same width nor circumference. I wrote to the seller, but I received no reply. But then a few days later, I found a new posting by this same seller which offered one with the exact fit.  Boy oh boy, overjoyed, I couldn’t care less about the price, I placed the order on the spot.

I received the belt, and comparably all the dimensions fit, the difference in colour did not matter. I had figured out exactly the procedure I had to perform. All I needed was to loosen the handwheel, remove the drive shaft and replace the belt and fix everything. But the drive shaft was stuck fast, solidly stuck to the two ball bearings on each side of the gears. The operation manuals were useless. So, the rescue operation was stalled as it began.

Ha ha, good luck; someone on Youtube demonstrated how he replaced the belt of his lathe of exactly the same model. Full of expectations I followed his procedure, but the shaft held fast. Hammering harder and harder did not work, and hammering too hard might break the bearings or crack the housing. I had sounded like a blacksmith. So, the operation was stalled again.

I could take the whole unit to the car mechanic, but there was no certainty of success. Worse still, the housing might become broken or the bearings damaged, as the way car mechanics operate is well known. I had to be prepared. I searched on the WWW again on the availability of the bearings. I learned a full lesson on the types, functions, designs and usage of bearings through my search, especially bearing interference. With this knowledge I finally found the part number of the bearing on Aliexpress and that each cost a few dollars. What a relief, the bearings will be available.

Somehow I went into chat sites on the WWW and got to know about jaws and claws removers. These tools can remove bearings from shafts, what luck. Again, my search went on, looking for claws with the right dimensions.  There were myriads of sites selling two claws and three claws, but none were long and wide enough for my purpose, they were mostly for straightforward removing of bearings from shafts, unlike mine which is stuck in a housing. It was exasperating, with jaws and claws everywhere but not a one that could fit mine. In desperation, I thought of improvising, like removing the bracing struts to gain the full usage of the length of the claws. So I placed my order for one, with the thought that should that not work it still could be useful for other work which it might be suitable.

The two claws were straight while the three claws were curve but rearrange able for two claws operation by excluding one claw. The big problem was that it was difficult to trust the general dimensions of the parts stated in the postings. I wrote to several of the sellers and they all replied, but they were useless without being as specific as what I had requested. However one reply led me to figure out approximately from the pictures the maximum capacity that it could handle. I immediately made the order.

The two removers arrived in good shape. The two claws did fit with the bracings excluded, and I used clamps instead to hold the remover in place. But as I screwed the spindle the pieces could not maintained their hold and slipped apart, ha ha, proper job needs proper tools.

The three claws couldn’t embrace the shaft and bearing unit because of the housing being too bulky. I adapted the remover to two claws and that fitted. But then no matter how tight I screwed the spindle the shaft remained intact, stuck fast to the bearings in the housing. However I was confident that the operation was in the right direction, and one may not force things. So, I left things hanging; and each day I tried to turn the spindle a little without success.

Finally, I resolved to make or break. I took a bigger wrench and used my body weight and applied with all my strength. Phiak … it was a very short sharp sound. My thought was that the threads in the spindle had sheared off, having read that in one of the chat sites. But the spindle was OK, and the housing was not crack, and the two claws were OK too. Then I noticed that the bearing had come out of the housing a few millimeters. Ha ha, it had worked, what a relief. Finally with a few more tightening of the spindle the shaft came loose with one bearing attached to it while the other bearing remained stuck in the housing.

Replacing the belt and all else was OK, but I couldn’t put the handwheel back, the threads of the shaft were frayed in the process of the handling of the claws, wrenches, hammer and whatnot. Fortunately the threads were smoothened with careful filing away of the uneven surfaces of the threads, and the handwheel could turn in.

And finally the belt was replaced and the lathe fixed, a year later, October 2018.