| Gallery, Projects and General > Project Logs |
| Knurling tool E.Riley stile |
| << < (4/6) > >> |
| Fergus OMore:
I'm going to say 'No' because the Sherline is probably 3 times less rigid that Mr Riley's Myford which is a lathe which can swing 7". There is nothing wrong with the design but it was designed for much bigger things. Somewhere there is a lot of information on knurling and I reckon that the chances of damaging the headstock bearings is high. For those who are that bit younger than me( perhaps the whole lot of you?) I recall that Martin Cleeve actually built a outrigger bearing to take the strain imposed on his Glacier Bearings of his Myford ML7. So I might be wrong-- but I doubt it Norm |
| PeterE:
Hi Ralph, That knurling tool looks very nice, well done indeed! Then when it comes to use this type on small machines like the Sherline or the Unimat/MJ-189 they work well but should not be too large. I have the illustrated one which has a capacity of up to 25 to 30 mm diameter: http://www.chronos.ltd.uk/acatalog/info_391201.html It has been used for around ten years now and it works really well on both my MJ-189 and my C3 mini lathe. It does not have a very large knob so the pressure must be increased as the knurl forms. After ten years I have now noticed that since my tool does not have the support sides, the upper and lower arms tend to separate in the lathe axial direction forced by the angle of the knurling wheels. Becuase of this I am going to make a new one also from Hemingway but the larger sensitive one with the feed lever, scroll down one item. http://www.hemingwaykits.com/acatalog/Knurling_Tool.html BR /Peter |
| Fergus OMore:
I've also got a MJ189 ,Peter, but really this has been regarded as something for non ferrous metals and situations where the bigger lathe is otherwise occupied. I did an odd bit of rule of thumb engineering. I measured the diameter of my knurls against the bearing diameter of the main bearings of the MJ189. So on the same reasoning, could I use milling cutters of the same diameter? After all, there is not a lot of difference in the cutting action of both. What say you, please? Cheers Norman |
| PeterE:
Hi Norman, Perhaps my experience is due to not being completely knowledgeable in such matters and thus having taken the risk to overstrain my machine unknowingly, but the scissor knurling tool does not put radial strain on the machine as it floats radially, it only increases the load on the transmission and motor in contrary to the "press sideways to knurl-tools". I have at least not found that it affects the headstock bearings. One must be careful though to take the time needed and not rush the work. The comparison with the milling cutter is interesting, have not thought about that, but what about a fly cutter which acts on a larger diameter than the exemplified 25 mm knurl, at least my Unimat flycutter is able to span 50 mm diameter. Wouldn´t that strain the little machine more as the single cutting edge whirls around a diameter and thus generates a rotating radial load as well? I think that it works because it is not possible to create so high loads that the bearings get damaged, the round belt (rope) transmission will bail out long before and act as protection. The headstock bearings are 17 mm inner diameter which is quite a large diameter axle that may handle substantial radial loads, I think far larger than possible to generate on the machine, but I may well be very wrong ... Well this is my 2cents .. BR /Peter |
| andyf:
I think Lou was referring to a Sieg mini-lathe (7" swing, 3.5" centre height, similar to a Myford) rather than a Sherline or Unimat. The Hemingway kit was probably designed to fit a Myford, so should be the right size for his lathe. As Rob Wilson says, it looks as though it could be made with hand tools, though a drill press would make life easier. Andy |
| Navigation |
| Message Index |
| Next page |
| Previous page |