I may have to do a video review on my lathe preferences.... I do get asked this a lot. For starters, I do not like turning bowls on long bed lathes. They do not allow you to stand up straight to turn bowls without having to extend your arms out away from your body, or you have to lean against the lathe to turn, and I don't like being unbalances. When I saw the 3520A, I was instantly in love, without even trying it. Made perfect sense, slide the headstock down to the end and turn bowls and stand up straight for all of the cuts, while being able to keep your arms in close to your body. Also worked for boxes and hollow forms. Slide to the other end for turning spindles. The other alternative to the sliding headstock is the pivoting headstock. The first versions of these were pretty funny... Lots of fussing and fiddling to get it back into proper alignment. The Vic 240 eliminates this. One stop, with a pin, at 0, 30, and 90 degrees. The set pin allows for exact repeatable alignment every time. The 30 degree setting is perfect for being able to stand up straight, and still be able to use the banjo that comes with the lathe. There is a set screw/pin, like the one on your banjo, to anchor the rotating plate in place to eliminate any vibration. It is rock solid. I guess I could get used to turning on a long bed lathe, but don't want to.
So, if you have seen Stuart Batty, Mike Mahoney and maybe Glenn Lucas, they all comment about how the sliding headstocks and pivoting headstocks cause added vibration. They all turn on the Vicmarks. They make the same comments about the steel bed and ways lathes. After pondering this, I do not agree for a couple of reasons. Some of the early sliding headstocks used the same pressure plate on the bottom of the headstock that they used on the banjo. That idea should not have made it off of the drawing board because the headstock takes a lot of abuse as far as pressures endured during turning. If you look at the AB, the pressure plate on mine is the same length as the headstock tower. On my 3520A, first one was cast iron, which broke when I was coring some black locust. I replaced it with a 1/2 inch metal plate and a couple of strips to fit in between the ways. I think it was about 4 wide by 6 inches long, which I consider to be ample. So, when I first got my AB, right away, I noticed some vibration when turning medium sized bowls, 10 and over. Note here, I rough with scrapers, and with my PM, I almost never used the tailstock, and carried that habit over to the AB. So, why was I getting this vibration that I never had before? Best explanation I came up with is the bell housing for the headstock spindle. This extends the piece out another 2+ inches away from the headstock tower. This idea first came up, at least as far as I know, on the Oneway lathes. The purpose of it was to allow you to remove the headstock spindle as a unit rather than having to remove the entire headstock if you want to change the belt or bearings. It also allows you to have more access to the outside of the bowl. Having that access is a good idea if you twice turn your bowls, which I don't. When I reverse my bowls, they are finish turned on the outside. If you look at the headstock design of the Vicmark lathes, it comes directly off of the headstock tower. That extra cantilever distance of 2 inches can make a big difference in vibration issues for medium sized bowls. Another note here, when turning your bowls, if you use the tailstock, there is no turning vibration at all. If I don't have to use the tailstock for stability, that is a time saver for production work. Next time I get to see Stuart turn, I will bring this up with him. Worst case I ever saw for the headstock design was the early Laguna lathes where the housing extended out 4 or more inches off of the headstock, which they seem to have modified. I guess that if I want to turn bigger bowls with no tailstock support, I should get a VB36.... Don't think I will add that one to my arsenal, but I have been thinking about adding another Vic. Of the lathes out on the market that I am familiar with, the best manufacturing quality ones are the Oneway, Vicmark, and Robust. I have no experience with the Harvey or Titan lathes. Never turned on one of the Serious lathes, or a Nichols lathe, which are not made any more...
I have wondered why those who twice turn their bowls don't finish turn the outside before they reverse it to true up the inside of the bowl. With my once turned bowls, I usually have less than 1/16 inch run out in my bowls when I reverse them to turn out the inside, and that measure comes out to +/- 1/32 of an inch. That small of a run out is only going to make a difference if you are trying to turn less than 1/8 inch thick walls on your bowl. It takes some practice to do this, but it isn't too difficult. As I said, I have almost no experience with twice turned bowls, I prefer the warped ones and they have always sold very well for me...
As near as I can tell, the stainless steel ways and tube bodies of lathes like the Oneway and Robust make no difference in vibration issues at all when turning. Only real difference I noticed was that the lathes made different noises when I turn. The same appears to be true with the headstock mounted in the middle of the bed rather than close to or directly over the legs of the lathe.
Both my AB, which was one of the very early ones, and my Vic have 3 speed pulley systems on the headstock. This I prefer. On the 2 speed lathes, low speed is too slow for a lot of the smaller bowls I turn, but perfect for coring. High speed has the speed range, but not the torque for coring or turning larger pieces, Mid speed range is just right. I don't want to have to stop and change belt speeds. Maybe if some one made an automatic transmission for lathes so they could have more speed ranges, other then the Reeves drive, that could be really good, but probably too complicated for a lathe. If minimum speed is 50 or above, that is a deal breaker for me.
Oh, one other thing I prefer about my Vic, is the low speed, which seems to be in the 10 rpm or less. This speed is essential for sanding my warped bowls, and even if they aren't warped, I prefer those low speeds for sanding all my pieces. It allows me to see the bowl surface as I sand. The Oneway goes way down, and the 3520A did, then there was a trend in the industry for the lathe to turn off at 50 rpm. I think they are coming back around on that one. For sanding purposes or some slow set finishes, it is essential. The motor actually runs cooler when running at those slow speeds. I did have Brent help me adjust the converter so the AB would run down to almost 15 rpm. No clue as to what the minimum speed for the 3520C is.
I am not an engineer by trade, but my dad is, and I think like one, "If it ain't broke, take it apart and fix it anyway." There are always ways to improve things. I guess if I was 20 or 30 years younger and into turning seriously, I would design and build my own robo hippy lathe. Just have too many other things to do now...
robo hippy
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Originally Posted by Randy Heinemann
