(Mini Lathe)Potecting Leadscrew

[GeorgeD]

How are those shields fitted and what material is used to protect the leadscrew from swarf? I've protected the saddle gears by using a perspex plate over the back of the saddle where swarf seems to accumulate terribly but the leadscrew needs a cover now.

Stripped the machine right down to the bare metal used a dremmel to remove the bad casting spikes on the inner of the bed and removed rust that was primed over in the factory(Really bad/poor steel used on these lathes castings) repainted it with metal paint and it looks really nice now.

Also done a bearing change and changed the puny little 3 jaw self centering chuck for a 100mm 4 jaw independant chuck.

:whistling:

[routercnc]

Hi George,

I don't know about your leadscrews specifically, but bellows arrangements (commercial and homemade) might be an option for you to keep swarf out:
http://www.youtube.com/watch?v=EV-eHIGzMPg&feature=related

[GeorgeD]

How do RCNC.

Nope,that wouldn't do,ye see the saddles carrige has two items in the way ie the gear that tracks along the rack and then the half nuts to engage with the leadscrew for auto feed.

I'm stumped as to how it works?

7th pic down shows the protection,although this saddles apron is different to the C2/C3....
http://www.toolsandmods.com/apron.html

[GeorgeD]

And howits doneonthe SC2....

[GeorgeD]

Ah,Ive sussed how to do it but I need 1" diameter 5" long springs? anyone know whereto get these?

Put flax cloth around springs,feed the springs on to the leadscrew either side of the apron and thats it. :)

[irving2008]

the clue, George, is in the text... "spring type leadscrew covers " These are some form of wound spring steel or maybe plastic strip with the outer attached to the saddle and the inner end attached to the leadscrew bearing block, possibly on some form of swivel...

like these (http://www.ondrives.com/springs-leadscrew-guards-39-4-115mm-max-dia-over-guard.html)

let us know the price when you find out...

[GeorgeD]

The leadscrew is 16mm and these are 16mm :-(
http://cgi.ebay.co.uk/66300-HOT-BODIES-SHOCK-SPRING-16X90X1-6-14-75COILS-WH-/380271602848?pt=UK_ToysGames_RadioControlled_JN&hash=item5889f42ca0

These will do but the price will not...I only need two,not 16 :-(
http://cgi.ebay.co.uk/86764-HPI-SHOCK-SPRING-SET-23X155X2-4MM-16COILS-BLUE-/380272125887?pt=UK_ToysGames_RadioControlled_JN&hash=item5889fc27bf

The tension looks about right? can't have it too stiff,could cause a problem on the autofeed?

[GeorgeD]

Will give this a try.....washing machine waste outlet pipe,this is plastic over spring ...just might be what the doctor ordered and is the right diameter?

[irving2008]

The leadscrew is 16mm and these are 16mm :-(
http://cgi.ebay.co.uk/66300-HOT-BODIES-SHOCK-SPRING-16X90X1-6-14-75COILS-WH-/380271602848?pt=UK_ToysGames_RadioControlled_JN&hash=item5889f42ca0

These will do but the price will not...I only need two,not 16 :-(
http://cgi.ebay.co.uk/86764-HPI-SHOCK-SPRING-SET-23X155X2-4MM-16COILS-BLUE-/380272125887?pt=UK_ToysGames_RadioControlled_JN&hash=item5889fc27bf

The tension looks about right? can't have it too stiff,could cause a problem on the autofeed?

errr... but these have holes.... the stuff I was looking at is flat strip and overlapping so there are no gaps...

[GeorgeD]

errr... but these have holes....This iswhere your needle and cotton(darning skill)comes in handy...you make socks for the springs. :wink:

[Swarfing]

Do a google for 'jean way covers', these can be constucted into a box section and all it will cost you is a pair of old jeans and some varnish

[Swarfing]

This type of thing

http://www.youtube.com/watch?v=5EgLMMhbRfc

[bogstandard]

Be careful, my large lathe came with protective spring covers on the leadscrew, and I had to have them removed at the factory before delivery.

With it fitted, it restricted the movement towards the headstock so much, I couldn't get the tooling to reach the faceplate, even with the compound fully forwards.

Maybe you should do what has been done for the last century or so. With the leadscrew turning, just brush the swarf out of the thread with a 1" paintbrush.
Besides, the covers are not there to keep swarf out, that is just a secondary feature, they are supposedly a safety feature to stop fingers getting mashed. Swarf will find it's way underneath them without fail, past your apron, then you will have the unseen swarf grinding away at your half nuts.

I had a hell of a job with the H&S legal eagles, and had to sign a release note to state that I wouldn't sue the suppliers if I had an accident after the covers were removed.

They are not all they are made out to be.

Bogs

[GeorgeD]

How does one manage to trap their fingers behind the leadscrew? there is no need for the fingers to be in that area as it serves no purpose.

Swarf on the lead screw can hinder the auto travel and in turn possibly ruin the job?

This apron mod also helps considerably,along with the leadscrew guard will reduce the swarf getting onto that area...not saying it will not find its way onto the leadscew but you can bet your last penny it will minimise it more than it will without protection.

http://www.mini-lathe.com/Mini_lathe/Modifications/modifications.htm#Chip_Guard

[Jonathan]

the covers are not there to keep swarf out, that is just a secondary feature, they are supposedly a safety feature to stop fingers getting mashed.

:smile: Yep, I remember at school the teacher would disable all the auto-feeds on the lathes before the health and safety man came round - because they didn't have covers! Was a bit annoying on the once a year or whatever that he came...



Swarf on the lead screw can hinder the auto travel and in turn possibly ruin the job?

I doubt it would ruin the job. The swarf will wear the half nut which i guess would make a tiny difference to the accuracy....but not ruin it.

[GeorgeD]

Had a look at the washing machine wastepipe,its too stiff because of the plastic covering the wire spring.

So needed to think again....no need for any sort of guard....two small brushes affixed either side of the halfnuts so that as the apron is travelling up and down the leadscrew the brushes are wiping the leadscrew from swarf.
The brushes(if I can find it?) will be a piece of door draft excluder this is like those old vac cleaners with a bristle head on them to flick particles of debri out of the carpet.

This should do it. :whistling:
http://www.reddiseals.com/acatalog/DraughtExcluders_lrg.jpg

[Jonathan]

Brushes sounds like a good idea. What about using a toothbrush in the right place, or one of those wire (brass) brushes...I think you'll want something quite stiff for it to be effective.

[GeorgeD]

I think you'll want something quite stiff for it to be effective.True,and I have the answer :smile:dremmel brushes,these ones look like miniture chimney sweeps brushes and are really stiff bristles,they're not the brass ones which are the same style dunno what these bristles ones are for on the dremmel drills?never used them for anything.

Here's the fella....

http://www.dremel-direct.com/acatalog/403_19_0mm_Wheel_Shape_Bristle_Brush.html

Jut need to make a crontraption now thats easily removed?