|16 forum posts|
Having got an understanding of Gib strips and correct set up, I noticed my cross slide and compound slide feed screw nuts are worn, the cross slide has a little play and the compound quite a lot.
Can I replace the nuts and be ok, or must the screws be changed as well?
Would the Arc Euro Trade bearing mod fix things cheaper?
|Grindstone Cowboy||26/04/2019 01:11:45|
|112 forum posts|
Have a read of this thread **LINK**
|Mark Rand||26/04/2019 01:30:47|
|729 forum posts|
As well as the linked thread, the nuts are a 'consumable' item. They were originally Mazac/Zamac/zinc alloy and wore in preference to the feed screws. They are an easy, cheap replacement and worth doing before you replace the screws themselves, but the cost of the complete screw+nut assembly is cheaper than the original Myford Beeston parts were.. The Myford/RDG web site has them listed.
|not done it yet||26/04/2019 09:08:17|
|3166 forum posts|
The decision on whether the screw and nut needs replacing should be based on backlash readings at different points along the screw.
Also depends on your subjective “little” and “quite a lot”. There will always be “a little’ backlash. But there should be no end-float from other causes.
|Douglas Johnston||26/04/2019 09:38:51|
590 forum posts
Just had a look at the Myford/RDG prices and have to say the word "cheap" did not come to mind, but perhaps that says more about me than anything else. Over £400 for a topslide , good grief you could buy a whole Chinese lathe for that.
3651 forum posts
Plenty of good used topslides on eBay for about an eighth of that amount. They are not a high-wear item so a safe bet to buy used.
|Peter Sansom||26/04/2019 13:53:20|
|58 forum posts|
For power crossfeed on the S7 you need to purchase the nut/screw assembly, otherwise you can just purchase the nut, unless it has worked hard in an industrial environment. My S7 was 25 years in an industrial setting, I replaced the nuts when i acquired it.
Everything else can usually be fixed by adjustment
|Dennis Pataki||26/04/2019 16:29:18|
|7 forum posts|
Keep in mind that a worn feed screw will affect the accuracy of movement as shown on the graduated dial. This is most noticeable over a long distance of movement due to wear differences in the screw threads.
A worn nut will only affect the backlash due to excess clearance between the screw and nut.
3651 forum posts
There is also the old dodge of cutting the threaded section off the screw, turning it round endwise and re-attaching it with a suitable spigot pin and silver solder. This moves the worn section to the least used end of the leadscrew. Works best with the main carriage leadscrew but not sure where the cross-slide nut rides on the S7. If its in the middle then obviously no advantage to be gained but if its at one end could be worth doing if the screw is badly worn.
|Howard Lewis||27/04/2019 08:58:36|
|2156 forum posts|
Only changed the worn nut on the Cross Slide on my ML7 when I had one.
Although, eventually did upgrade to the long Cross Slide and Leadscrew.
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!
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.