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Thread: TOS lathe?
01-20-2008, 10:58 PM #1
Hi, I am new around here, and was hoping someone could help me out. I just aquired a TOS Trenchin SN40B-50B lathe and have some questions.
First, does anyone know what the -50B in the model number means?
Second, the manual that I got for it says that the lathe has foward and reverse, but mine seems to only run in foward-and the previous owner seemed to agree. The manual states that when the carriage lever is lifted up, the lathe will run foward-is this correct? The lathe was set up to run foward when the handle was pushed down, when you bring it back the clutch disengages, and if you lift it up it brakes(as in puts on the brakes).
I also notced that when the carrige handle is in the center locked position, the spindle will sometimes creep ever so slightly. Is the clutch and or brake worn or need adjustment? Was the previous owner and now me running the motor backwards, possibly causing the reverse to not function properly? Or do I have some strange lathe that doesn't have reverse?
Third, the lathe came with a large tool post that I can't seem to find anything about. It says- IMPERO M/T.16
It has a wedge-type quick release on the left, some other type of large quick release on the front and a large set-screw tool holder on the right. It has a couple of the wedge-type tool holders, but there seems to be parts missing-namely a way to set the tool holders height in the tool post.
Also I have no tool holder for the large front quick-release part.
Does anyone know anything about this toolpost or where I can find info about it?
Finally, the cross-slide in particular has a lot of sloop(you can grab the toolpost and move it back and forth app. 3/8 of an inch!). Is there an adjustment here or is the part that the leadscrew mates to just badly worn?
Thanks in advance for any help!
01-21-2008, 02:28 PM #2
I purchased a used Tos lathe in November and still don't have it powered up and it's a little smaller model than yours. The good and the bad, the 40 and 50 series lathes seems to have been one of their most common models for mid size production use, their should be lots of machinists that have quite a bit of operating time on them, the bad news is I have seen precious little information on them here and otherwise. One might assume the 40/50 # would indicate the spindle bore in mm's but doesn't seem to, I've seen both with 2" and some slightly larger.
I would think your directional problems are likely a linkage/engagement issue and you might see more with a cover removed, it could be that it was wired opposite (easy to happen on 3 phase) but I would think that your directions would still be there just opposite? Does the lever have the proper movement? Maybe you have some switching issues? I would think this machine has reverse.
Haven't heard of that toolpost, but I have limited education thusfar, if you could borrow some other holders to see if they interchange (probably CXA size) If not and you have some odd bird it maybe better to flog what you have on ebay and pick up a popular system?
Is the mount loose underneath?
Sorry to not be of more helphopefully this will bump it back up top to someone who can:rolleyes:Good luck!
01-21-2008, 02:34 PM #3
3/8" slop in the crosslide screw is a lot , that's usually more than the pitch of the leadscrew/nut pair, sounds to me that the locking device at the end of the leadscrew has come loose. Regards Tyrone
01-21-2008, 02:37 PM #4
Usually ( but not always) pushing the lever down gives you forward rotation , up normally is reverse. Regards Tyrone
01-21-2008, 04:55 PM #5
Yes, that is what I thought, and why I asked.
I came here because I found some posts by some people that seemed to be familar with the TOS. I am not a machinest, but have wanted a lathe for many years and am really excited about this-it would appear that I got a really nice machine, it's just in need of a little love.
Oh yeah, as for the slop, I checked the compound(?) slide( the one the tool post bolts too and is adjustable for angle) and it had a ton of slop also. So I took it apart this morning and and found a bolt missing from the lead-screw block(is that what it is called?), so I thought that was the problem. While that wasn't helping , it was not the only problem. I did find a threaded collar that holds a thrust washer against a thrust bearing at the hand wheel that had come loose, however, and this appears to be the main culprit. I will find out today, and I am hoping the problem with the cross slide is the same.
I cleaned out all of the little spring-loaded ball oil ports. A few of them were so packed with chips that they were stuck open. I am trying to flush them out, but I can't seem to get them to take oil. Is there some kind of special gun I need? I have a little zoom-spout oiler right now. What kind of oil does this need? Way oil? I have some that I bought for my mill, is this what I should be using?
"I would think your directional problems are likely a linkage/engagement issue and you might see more with a cover removed, it could be that it was wired opposite (easy to happen on 3 phase) but I would think that your directions would still be there just opposite? Does the lever have the proper movement? Maybe you have some switching issues? I would think this machine has reverse."
There is no real switching that I can see-it's a clutch and, I'm assuming, a back gear of some sort for reverse that is actuated by the carrige lever. I will try to remove some covers to get a better look at it and see if it begins to make more sense.
Thanks again for all your input!
01-22-2008, 05:26 PM #6
I used a SN50 and an SN60 quite extensively, my father owns them.
1. SN40B-50B is a bit of an oddity for a tos model #. On all the tos lathes I've seen it would normally be either SN40B OR SN50B, the 40/50/60... roughly refers to the swing over the bed. 40≈400mm and so forth. A/B/C I believe somehow refers to the spindle bore.
2. The SN lathes have a dual clutch pack same as most other modern lathes, there is a panel on the rear of the headstock that gives access to the clutches. Lever down=forward, up=reverse. If the spindle creeps in neutral, one of the clutches is too tight or the selector is not going into the neutral position properly. If it won't reverse most likely the clutch selector is worn or needing adjusting, or there is excessive play in the clutch lever linkage. It is unlikely that the clutch packs are worn out. You should be able to feel a positive "clunk" in either direction as it engages fully.
3. Impero are Italian, high quality and horrendously expensive to get parts for. If you really want to get parts or holders I'd recommend you watch for them on eBay, otherwise abandon it and get a standard toolpost. I'm also not sure if they still exist as a company.
4. Assuming you don't have a taper attachment fitted, there are two places the slop can come from. On the end of the leadscrew at the rear of the carriage is the thrust block, there is a thrust bearing either side and a locking nut to pull them together. That may be loose or the bearings may be shot. The nut is adjustable also, on the top of the cross slide you'll see two socket cap screws either side of a slotted pin with a oiler in the centre of it. Slacken one or both of the cap screws, and twist the slotted pin with a flat screwdriver to open the nut. Unless the nut is very worn the pin should turn only very slightly. Given the amount of slop you describe I'd put money on the thrust bearings are loose.
If you don't have a parts book the 600 group UK can supply one.
Hope some of this helps, Gregor
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01-22-2008, 06:19 PM #7
gregormarwick is dead right about the swing & the number corresponding, ie SN40 + 400mm or 16" & the machine should run forward with the handle down. I have owned an SN 40A, SN 45B , two SN45C's & a 50b. I take it you don't have taper turning? If you do the cross feed lead screw is anchored on the taper turning attachment. On the A series machines there was a lever to disengage the reverse clutch when reverse wasn't needed. They seemed to have dropped that on the later machines, at least those sold in the UK. The spindle creep, there is a brake on these machines, adjustable at the rear, near where the clutch operating lever terminates.There are two speed ranges available-- under the cover where the change wheels are is gearbox, the cover is held on by two screws, simply swap the gears round for the alternative speed range, max 1000 in one range, max 2000 in the other. I have a manual for these machines & some layout drawings, will try & get them on-line. The head bearing arrangement is very unusual,perhaps unique, but easy to work on once you know how.On the UK machines you need extra change wheels to cut eleven & half tpi, thirteen tpi & twentysix tpi. Very solid hard working machine.
01-22-2008, 07:12 PM #8
OK, thanks you guys! Yesterday I had some time and mostly solved the backlash problem-as you suggested gregormarwick the problem was with loose nuts. I took it all apart, cleaned it, re-greased it and a little locktite on the adjuster nuts should do the trick. I took some pics, if I get a chance perhaps I will post 'em-maybe it will help someone else out too.
On the little slide, the missing bolt was missing because a second one will not go in. Is the lead screw block the wrong one? Also, if i tightened the one screw too much, the handle would be hard to rotate as the block got closer to the thrust bearings-as is the lead screw was bent slightly. I finally setteled for a comprimise that would give me the least amount of slop without binding the leadscrew too much.
I don't have a taper attachment(it goes on the back side of the carriage, right?) And frankly have never seen one in person and am therefore puzzled as to how it works.
The machine also did not come with any other gears other than what is on iy right now-hopefully they will work for me.
As for the speed changing gears, I was just reading about that in the manual and trying to figure that out. I will go and look for the cover you mentioned and see if I can figure it out.
I was going over the clutch and brake drawings and descriptions again and will try to look at those too. My books drawings are a little confusing, as the they are kinda like exploded views, but not quite and the placement of a part on the page isn't always where it seems to go. The descriptions aren't that great either for trying to figure out how a part works or what it is for-instead of something like" clutch shifter connecting rod" it will just say "rod". Great if you already know all about the function of the parts but not too helpful in telling a dummy like me what the part really does!
Thanks again for all of your input!
01-23-2008, 12:09 AM #9
You probably shouldn't use grease, unless the manual explicitly says to use it. Grease captures metal chips which will prematurely wear whatever it is you're trying to lubricate.
01-23-2008, 12:40 AM #10
Thanks for the grease tip. I only greased one non-contact surface, and the bearings and gears of the slides, not the ways, which I coated in way oil, so hopefully I'll be OK.
But now, has any one had to adjust the clutches on one of these? I got the cover off, and found how the adjustment works, but I still couldn't get it to work right. It just seems that the shift fork runs out of room. So I took the entire assembely out of the machine, and took the reverse clutch pack apart. It all appears to be there, but it just does not seem to be able to create tension like the foward side does. I'm wondering now if the little levers that are depressed by the shift collar and then press on the clutch pack are some how worn or bent, but I have no way of knowing what they should look like. It seems that there are rounded cross grooves for these levers to ride in on the clutch shaft, but I don't THINK they are touching.
Man, oh man, I wish I could just talk to someone who has worked on one of these before so they could tell me what to look for.
01-23-2008, 10:09 AM #11
I have adjusted the clutches before on the SN60, but it was a while ago and I can't quite remember the particular setup. If you could scan and post the relevant parts diagrams it would probably be enough that I could help you. As I said before, these are my father's machines and I don't work there anymore so I can't check myself!
01-28-2008, 01:17 PM #12
OK, thanks again to all who have chimed in.
I believe I have now figured out all of the problems, but I still have to fix the reverse.
As I said, the slop in the slides was mainly due to loose thrust bearings-those were fairly easy fixes.
As for the reverse issue, after taking apart the clutch shaft and looking at it real close, I determined that at some point someone put the levers that put pressure on the clutches on wrong. As a result, they were never capable of exerting pressure on the clutch pack, and it seems to have worn deep groves into the levers as well. I put the pack back togather the correct way and got reverse working, but it has since quit working, I suspect that when disengaged, the levers were able to fall out of their place and get hung up due to these grooves.
I will try next to post a few pics so that if anyone else has a similar problem they may benifit from my little ordeal.
Also, I had a hard time finding anyone who knew anything about these and could confirm my suspisions about how the parts worked and were supposed to be installed-as well as finding parts. I did find a gentleman who works for a place called Modern Tool (http://www.moderntool.com/calgary.htm) in the service department who was VERY helpful. He had a very good working knowledge of these machines, and told me some things to try, some things to look out for, and some tips for helping it out. I am sorry to say that I am horrible with names and can't remember his, but would like to thank him very much.
Also they can order parts for this machine.
And as far as parts go, I found a guy in N.J. who I purchased a manual off of e-Bay from for this machine.( http://cgi.ebay.com/Tos-Trencin-Inst...QQcmdZViewItem) His name is Gary and he was most helpful as well, AND he has a lot of common parts for this machine in stock.
01-28-2008, 01:42 PM #13
Ok, here is where the thrust bearings are for the cross slide. This is on the back of the machine, and there is a cap with 4 bolts that cover this and act as the thrust block. At the end of the lead screw shown is where you tighten the jam nuts to adjust the bearings.
Here is the clutch shaft taken apart-this is all the parts in pretty much exploded form except for the actual shaft, and the drive pulley and it's spacer, key, and retaining hardware. the top row of parts is the reverse section, ending with the shift collar which resides in the middle of the shaft. The bottom row is the foward section. These bearings are all light press fit to the shaft and removing a few of them is alittle tricky. with some care, patentience, and a large pry bar you can remove the ones that wont fit in the press by "wiggling" them off the shaft. The parts go onto the shaft in order from top left to top right, then bottom right to bottom left.
01-28-2008, 01:56 PM #14
I would have expected a third clutch on that shaft to act as a brake. Regards Tyrone.
01-28-2008, 02:02 PM #15
Here is what the reverse levers looked like when I removed the reverse gear. You can see the levers are perched on the outside lip of the ring that presses against the clutches, and are held there by the grooves cut into them. This is wrong, and holds the lever fingers away from the shaft, which is their fulcrum point. The shaft has radiused slots cut across it to recieve the rounded elbows of the levers, and when held off the shaft they cannot apply presseure to the clutches.
Here is what the levers SHOULD look like when installed. Notice they are inside the lip of that ring, which both holds that ring centered and keeps the levers in contention with their piviot points on the clutch shaft.
Here is what the reverse side of the clutch shaft looks like when you press the bearings and reverse gear back over the clutch pack. From left to right you will see on the shaft: foward gear clutch adjuster; shift collar; reverse gear clutch adjuster; inner and outer clutch discs nested inside of the reverse gear; and the reverse gear.
So in a nut shell that is how the clutch shaft goes togather. My only problem now is that I don't have reverse(need to get some new parts) and I did not set the foward clutches tight enough-which is a bummer, 'cause to adjust them you have to drain the oil and remove the back lower cover off of the machine, and I dont know how to adjust them to the proper tension without running the machine.
Does anyone know the procedure to adjust these? That would be a grat help!
01-29-2008, 03:20 AM #16
I just read today that 600 group had lost the agency for TOS.
I'm sorry, I didn't register who got it, but I think it was in the TOS thread on General New, the post was a day or two ago.
01-29-2008, 06:36 PM #17
The guy who imported the new Trens lathes to the UK was Budget Machinery which is the company the link refers to in the other post.He decided to approach Trens after the 600 Group called him up one day and asked if he could supply spares for a TOS lathe.(he has a lot of dealings in Poland and Slovakia).He asked 600 why they did not ask the agent and they replied they did not know who it was.He then told them it was the 600 Group.He also does Heltos drills which he is very enthusiastic about.Sold hundreds over the years and has only had one warranty claim,which was for a broken return spring.
02-03-2008, 09:07 AM #18
If I am not mistaken , Modern has recently aquired the new import rights for TOS..
,, Omni trade used to be the importer in jersey, Phil was his name, he had lots of steady rest and stuff for sale, He was selling on ebay under http://myworld.ebay.com/mrmachinery8ts4 I cannot find his number.. If you have it, please send me a email..
The other guy you talk about, I believe used to work for him... I've got the manual from him.. It does explain the clutch issue.
I had burnt mine up on a heavy rev. cut.... purpled the housing, shaft..
If your electric motor is reveresed? how was the oil pump pumping oil to the uppers?
AS far as adjusting.. I"T s a feel thing.. you have to run it to see if' it's slipping ie, cut heavy.. then re adjust.. primitive. but it works... Also make sure you use the right oil...
02-03-2008, 09:16 AM #19
I ran mine with the rear cover off, gets kinda messy,, put lots of cardboard down..
adjust a couple of clicks at a time, quick test run..
One thing to watch, if the clutch is too tight, it will drag the opposite clutch, and heat up..
IE , forward too tight, run it in rev. and it's fighting each other..
02-03-2008, 10:08 AM #20
And if you have to drain the oil to set the clutch you have to much oil in the gearbox The oillevel is below the lower side of the hole behind the cover