Chris machin | 11/02/2012 20:12:31 |
59 forum posts | Hi All ,
I Have a Clarke 300 lathe. On the crosslide you can rotate the handwheel two revolutions before the crosslide starts to move and hence appears to have excessive backlash ! Is this adjustable or is it more serious ?
The other directional movements are fine.
any advice much appreciated
![]() Regards
Chris. |
Ady1 | 11/02/2012 20:37:33 |
![]() 6137 forum posts 893 photos | It should always be less than a single turn shouldn't it? Next project...priority 1...make a new cross slide nut... |
Sean Cullen | 11/02/2012 21:05:47 |
55 forum posts 11 photos | Try checking the adjustments section of mini-lathe.com plenty of useful advice there. In fact the whole site is full of useful stuff based on the writer's experience. Which reminds me, I mst adjust my cross slide Sean Cullen |
Bazyle | 11/02/2012 23:43:20 |
![]() 6956 forum posts 229 photos | I don't have this lathe but it is unlikely that the nut is that bad so soon unless it's made of jelly. My 60 yr old lathe isn't that bad. Grab the cross slide and pull/push it back and forth and see what moves and where there is a gap. You will probably find there is a nut holding the handle on that needs adjusting. It is common for the handle to screw onto the screwed shaft to adjust until it just turns without binding. This is then locked with a nut. |
Ketan Swali | 12/02/2012 10:14:06 |
1481 forum posts 149 photos | A Clarke CL300 is a SIEG C2 mini-lathe. You may wish to consider downloading this prep.guide which is for a C3, which is a slightly bigger version of a C2. Many bits on the C3 are same as on the C2, except, motor, control board, rev counter, distance between centres and weight.
http://www.arceurotrade.co.uk/projects/prepguides/C3%20Mini-Lathe%20Preparation%20Guide.pdf
Ketan at ARC.
|
Mike | 12/02/2012 10:15:31 |
![]() 713 forum posts 6 photos | Bazyle must be right: surely if it was a worn feednut, one revolution of free movement would indicate that the nut was completely stripped, and the slide wouldn't move at all. Or have I missed something here? |
Ian S C | 12/02/2012 11:04:39 |
![]() 7468 forum posts 230 photos | A friend had a similar problem with his Myford 7, and on stripping the feed nut and lead screw from the lathe it was found that the lead screw was badly warn, and the nut (some sort of muck metal)showed no sign of wear. Both parts were replaced. Grit had got into the nut, and it just lapped the leadscrew until it was almost gone. Ian S C |
Sean Cullen | 12/02/2012 13:46:36 |
55 forum posts 11 photos | With these lathes if they get out of adjustment they can have huge amounts of backlash. Adjustment is simple if you follow the instructions on the web sites recommended above (has to be simple if I can manage it ![]() sean Cullen |
Bazyle | 12/02/2012 14:48:46 |
![]() 6956 forum posts 229 photos | An interesting PDF given above. Someone put a lot of effort into producing it and woudn't it be great to have one for every lathe.
If you pull the cross slide handle towards you with one hand and hold it to take up any slack between it and the saddle, then use the other hand to move the cross slide itself. The movement you get will be the nut both its wear and slackness in the mounting screws. I think you've got a screw loose
![]() The as a different operation if you pull the handle while pushing the slide you will take up the slack in the nut. Keeping this tension on move both hands together back and forth and this will show the slack in the cross slide screw mounting registration.
I think in picture 156 of the pdf you see a ridge on the screw that forms this registration by being trapped between the almost circular boss and the saddle. So I was wrong abut the screw and handle controlling this. Idealy you need some brass shim washers here to take up all but a wisker of slackness.
I see one article about replacing the nice ball handle because the huge cap head screw gets in the way. Just replace the cap head with a normal hex head, with the head skimmed down a bit to minimum thickness, and if available replace the washer with a thinner crincle one too. |
Stub Mandrel | 12/02/2012 19:31:02 |
![]() 4318 forum posts 291 photos 1 articles | Whoa folks! No crisis - this is the standard symptom of the feed nut coming loose. The feed nut is held in place by two screws in through teh op of the cross slide, while a third 'grub' screw in between them controls the vertical postion of the nut by pressing on top of it. Screw the cross slide towards you as far as it will go - then adjust the nut. When tight you should get less than 10 thou backlash. Some advocate angling the nut to get even less backlash, but I can't see the point. Don'vertighten the screws or you will pull the thread out of the phosphor bronze nut! Spare nuts are available (don't ask how I know) ![]() Neil |
Chris machin | 12/02/2012 22:04:11 |
59 forum posts | Hi , Had a quick look at it tonight based upon the info people have posted (much appreciated
![]() I have found that the three screws that have been mentioned on the compound slide were loose. After loosening off the centre screw and then making adjustments on the outer two before retightening has resulted in a nice smooth crosslide with less than 1 thou backlash.
Really pleased this is sorted and thanks again to everyone who advised. ![]() |
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
Sign up to our newsletter and get a free digital issue.
You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.