Hi all. The backing plates and chucks I ordered came in. Below are pictures of the items 'as received'. and a few of my observations and opinions. Please bear in mind that I have no formal training, and very limited 'self taught' machining experience.
Below are the 4" and 6" 1-1/2 -8 threaded back plates from LMS. The cast iron quality is very good and the machining is also very good. They will normally require further machining on the lathe to make them concentric with the machine there fitted to. Shown is the back side that threads up to the lathe spindle register.
Below are the register sides (face sides) that the chucks bolt onto . The register (step) for the chuck is oversize which will allow for a truing cut on the face and register diameter to insure a concentric running chuck. The out side diameters can also be trued up, or reduced in diameter to match the particular chuck being mounted.
Below is the first problem I encountered. The scribe is touching the lathe spindle register. The back plates will only screw up to the register. Some quick measuring shows my register to be 1.534. x 3/8" long. The back plates are 1.500 x 1/4", and 1.501 x 1/4" deep. Its my understanding that the M39 x 4 back plates screw right on the China Made 9 x 19 without a problem. When I called LMS I was told these would also screw right on. My machine is the first and more expensive version that was made in Taiwan, and they came with a 1-1/2 x 8 spindles.
On the left is the 4" LMS back plate, and on the right is the factory furnished 3 jaw chuck with back plate. The difference in the depth of the register recess can be seen.
The 6" and 4 chucks that I got off of the E-Bay seller. One came with a 'Shars' label that fell of. I believe that both sellers and 'Shars' sell the identical chucks made at the same specs. They will need to be de-burred since the edges, and especially the edges around the adjusting screws are razor sharp. This typical finish up work is not a problem for me and should take less than an hour. We all know the old saying "You get what you pay for" and for about $50 they seem to be a bargain. But understand that I don't think that de-burring and buffing the corners will make these chucks comparable to a $500 Bison brand chuck.
The chuck 'keys' are so poorly made that I could only laugh! Their appearance compared to my average work makes me feel like a 'Master Machinist'. This was expected and again is not a problem. There are three ways to deal with this, ignorine their crudeness, buy better quality self ejecting keys (could be problematic on an adjustable four jaw), or machine up a pair of beauties.
Not much to say about the back side. I did check all the threaded holes and they are deep and A-OK.
The jaws are relatvly tight with very little play. The adjusting screws are ground and fit the bores in the chucks well. The running faces of the teeth on the screws and jaws are ground, but not the quality I would expect. The rest of the non- running surfaces are for a lack of a better word "crude". Clean it, close it, and forget it. The only concern here is, will this affect my ability to adjust a work piece to zero, and walk away with my sanity?
I took apart the 4" for cleaning and de-burring. It made quite a bit of difference in the the way the jaws open and close. And with the sharp edges gone I feel it was worth the effort for cosmetic reasons, and more importantly safety reasons.
Do I recommend this brand? Sorry, but you need to make you own choice. For me the small amount of use mine will get it may turn out to be all that I need. And the small amount of money spent won't stop me from buying a better replacement if it becomes necessary. Only time will tell.
-MB
-MB
