Sieg C2 mini-lathe mods

[spuddevans]

So after too long a break from posting up anything, I've decided to chart my progress as I try and improve my little mini-lathe.

Let me introduce the patient.



It is a Sieg C2A mini-lathe, badged by Axminster (I doubt if that makes any difference) I bought it about 5 or 6 years ago (I think  ) and up to now the only mods I have made to/for it is to chisel off the majority of the anti-rust "dragon fat" and to install a QC toolpost.

I have been quite happy with the lathe, it has done most of what I wanted from it. However, parting anything harder than warm moist butter has always been a little "Buttock-Pucker" inducing. Also the carriage has always been a little stiff, and the gears are constantly jammed up with swarf. The topslide (compound  I'm useless with proper terms) DRO has stopped working and the action has always been so poor I have just kept the gibs fully tightened up to lock it solid.

So what's the plan? Here's the list in no order of importance.

Tapered gibs on the carriage,
Carriage lock
Replace gibs on cross-slide and topslide with brass gibs (or learn how to scrape the existing gibs to fit properly)
Build a replacement QC mounting block to replace the Top-slide (I don't use the Top-slide/compound except on rare occasions, when I will re-mount the top-slide)
Convert the tailstock to a cam-lock.
Maybe change the headstock bearings to Angular Contact.



So I've made a start on the 1st item, the Tapered gibs.

Because I have only one lathe I made a start by making the gib-adjustment screws (it's pretty hard to turn them when the lathe is in bits)

The screws are M4 threaded, with a 11mm diameter head. Rather than wastefully turning down a long section of 12mm brass, I decided to follow (of a fashion) C.Fellows and make it out of a socket cap screw. Not having any M4 cap screws I used the next best thing I had, a couple of M4 Pozi screws, and a couple of 12mm "washers" I turned up and tapped M4.




Then I fluxed them up and set them up to silver solder in my little hearth.




In the interests of honesty, only one actually "took", I think that the screws may have been Zinc plated, which caused one not to stick, funny as the other one seems fine. So I had to redo one, but this time I turned the end of the screw down to 3mm, then drilled another brass "washer" to fit and then silver soldered it.


Then I chucked them back into the lathe and cleaned up the faces and turned them down to 11mm.




Then it was over to the mill to mill a screwdriver slot.




Resulting with this,




Having a little more time before the call to dinner, I started on cleaning up the hunk-o-rust that will become the gib brackets.




That's as far as I got, stay tuned for (ir)regular updates.


Tim

[ttrikalin]

Good job thus far!
Nice documentation and good photos.

Thank you,

Tom

[Roger B]

I would definitely recommend fitting taper roller bearings to the headstock. There are a few potential problems and with only one lathe you need a bit of planning.

This was my experience:

http://www.modelenginemaker.com/index.php?topic=2866.0

[spuddevans]

Thanks guys

This was my experience:

http://www.modelenginemaker.com/index.php?topic=2866.0

That thread has been bookmarked, some great info on the tailstock mods, thanks for that


Nothing much to show for today, I just removed the rust and squared up 2 lumps of steel, and in the process flattened a section of my carbide lathe tool that I used in the flycutter. ( I'm glad I wasn't using a HSS bit, I'd have been sharpening it every half inch )

Next will be stripping down the lathe carriage to measure up exactly where the mounting holes should be installed, then it will be onto milling the taper into the brackets.


My playtime in the workshop was cut slightly short today as I had to go to the post office to pick up a little bundle of toys from Arc   

I got a new Digi-vern (one of the new orange screen ones, bought to replace my last 2 that had suicidal tendancies and threw themselves off the workbench, which somewhat negatively affected their accuracy/use) a set of Stevenson's ER32 blocks (what a great idea) and a ballrace ER32 nut, and a couple of small items.

So, onwards and, Umm........  sideways

Tim

[MMan]

Hi Tim,

I built a replacement QC mounting block for my C3 (same thing, just a bit longer). The problems with the QCTP on the compound I was trying to fix were: too much overhang towards the chuck and too much flex in the compound slide making parting and cutting hard material eventful and cutting larger diameter work like flywheels, with the compound skewed round, was kludgy and not rigid enough.

Basically it is a 50mm cube with the QC parts recessed into it (unlike the standard one where they stick out) which mounts on a 20mm plate with T slots which bolts to the original swivel plate in the cross slide. The T slots let you move the tool holder out for larger work or, because it rotates on the swivel plate, move the tool post forward and back (for skimming things that won't fit over the cross slide). The hold down bolts through the cube are on a square pattern so that the cube can be rotated in 90 degree increments for boring etc. It takes the original holders although I might make some improved ones when I get to it.

Doing this has made parting much easier and I now get a far better finish on harder materials like silver steel (drill rod).

Pics below.

Mman

[spuddevans]

Hi Mman, Thanks for those pics, that's the sort of thing I am thinking of.

I started today by reducing the brackets down to the dimensions I needed, 19mm x 15mm. I decided to leave them a little longer than the carriage width for an idea that will be explained later (or if the idea turns out to be rubbish it will be forgotten about  )

Then I dismantled part of the Carriage in order to be able to measure it up. For those who may be wondering what the underside of a mini-lathe carriage looks like, wonder no more...




And before you ask, yes it did come with one cap screw missing. Setting these gibs up requires the employment of an octopus in order to loosen 3 screws while tightening 1 or 2 others. Hence the attraction to upgrade to a "single screw" operated tapered gib.

After removing the original gibs I set about measuring up to transfer the holes to the new brackets. I first up measured the diameter of a M6 capscrew, and then halved the result. Then I set my digi-vern to this value and zeroed it. Then by measuring from a datum edge (I chose the edge that would normally be closest to the headstock) to the far side of a M6 cap screw in each of the holes like thus,




And by repeating the same procedure but using the front or back edge I was able to note on the plans exactly where the centre of each mounting hole should be installed. I guess in the factory they just drill these holes without any real reference as no two holes were aligned!!




So after measuring, noting, drilling and de-burring I ended up with this.




Next up will be cutting the tapers, Thanks for watching



Tim

[Roger B]

Just a quick note, make sure that your thicker gibs clear the drive gear. Mine had very little clearance.

[spuddevans]

Just a quick note, make sure that your thicker gibs clear the drive gear. Mine had very little clearance.

That's a very good point, I will re-assemble the carriage and check that tomorrow before cutting any tapers, it'll be easier adjusting it now while it's still square. Thanks for pointing that out 


Tim

[Danny M2Z]

G'day Tim.

Re: Parting off in a mini-lathe. Turning a parting tool upside down and mounting it in a QCTP, then running the mini-lathe in reverse gives a similar result as the people who use rear mounted toolposts on other lathes. It is perfectly safe btw, due to the mini-lathe having a bolted-on chuck.

Also I found a tip which entailed slipping a small ball bearing under the tip of the gib screws to improve things in that department. I'me not sure how or why it works, but it does.

Also, a carriage stop is invaluable, saves embarrassing crashes and is great for boring work. (There are a few designs online)

I found that angular contact bearings are available in the same physical dimensions (ARC Eurotrade) as the standard bearings, so one does not have to machine the spindle to fit them (as you do if tapered roller bearings are used.

I took my Seig dro's off btw, they are not accurate (backlash) and prevent one from swinging the top-slide around to 29.5° for screwcutting by the single flank method.

Once they receive a bit of tlc, it is surprising how well these little lathes can be fine tuned.

* Danny M *

[spuddevans]

Hi Danny,

I've heard of that tip about the parting, hopefully when I'm done parting will be easier, but I will keep that in mind just in case.

Thanks for the other tips too. That's why I was thinking of Angular contact bearings instead of taper bearings, less Lathe-ing without the use of a Lathe.

I like the cross-slide DRO, as long as you remember about backlash, I've found them very accurate. But it is annoying about their size getting in the way. I intend to replace the top-slide for most work with a solid post for my QC toolpost.



Anyway here's your warning!! Epic tome ahead.


I had the day off work today, so I got to spend much more time in the workshop. 

Before I start on cutting the tapers I wanted to cut out for the gear, as you can see it will not do as it is at the moment.




Also I tried the fit of the new gib brackets on the lathe and found that the front bracket fouls the rack by just a little.




So I took about 1.5mm off that bracket and then, after measuring the offending gear as being 17mm, I used a 16mm endmill ( the biggest I have ) and made the cutout.




And here it is in place.




Now that's done it was on to cutting the tapers. In Bog's thread about Darren's lathe he temporarily glued a 1.5mm pin on one edge to set the taper, and I was going to do the same when I discovered I didn't have any superglue. So I came up with an alternative version, and verified it using my little digi-angle-finder. I used a 1.3mm drill bit to space one end ( circled in red )




Then I rough milled it with a 3/8" roughing endmill and then finished it with a 10mm carbide cutter. Then I did the same on the other bracket, remembering to get the taper going the right way.





I was hoping to mill up the gibs themselves, but when I looked through my stash-of-scrap I didn't have any suitable pieces of brass. ( I did have some that was way too big, but the price of brass is too much to mill that much into swarf )


So instead I decided to press on with another little mod, the cover for the handwheel gears on the carriage. As supplied, it looks like this.




I was going to get all technical and start measuring up and marking datums, but then I realised that I could do it much simpler. I measured the shaft to be 17mm and, after cutting out a suitable piece of 1.5mm ali sheet, I bored a 17mm hole in what seemed to be roughly the right place. Then I had to file a little radius on one corner (red circle) so that I am able to manipulate it in and one edge fits nicely under the half-nuts.




Then, while holding the ali in place, I traced out the outline of the casting with a pencil. (actually I had to do this twice as I smudged it the 1st time )




Then I rough cut it on the bandsaw, remounted it on the casting and held it in the vice and carelessly filed it to shape, and then drilled the cover for mounting screws (and gently marked the casting too)




Then it was over to the mill to align by eye and then drill 2.5mm. I was only able to get one clamp on it so I took it really gentle when drilling. ( this casting drills and taps like a dream )




I seem to remember seeing someone else doing a similar mod and they found that the gears sit a tiny bit proud, and their solution was to mill a recess in the cover to prevent the gears from binding. My lazy streak kicked in and I thought I could make it a little simpler. Both gears have shoulders to space them out from the casting, and I measured the shoulders at just over 1mm.




Now if only I had a working lathe !!! But I do have a vertical lathe, of sorts.




As you saw, I even aligned the tool with the very same ruler I use to set the toolheight on my lathe. Actually I had to do this twice as the above tool was the wrong geometry.

It worked just fine, all I needed to take off was 0.25mm from each gear's shoulder.





Then after tapping the m3 holes in the casting I was able to mount the cover.




This what it looks like in situ





Sadly the brass I've ordered for the gibs wont be here until at least tuesday, so I will have to think up some other mods to be getting on with in the meantime.


Tune in next week to see what happens.

Tim

[Danny M2Z]

Sadly the brass I've ordered for the gibs wont be here until at least tuesday, so I will have to think up some other mods to be getting on with in the meantime.

While you have the mill set up, this might be a useful addition http://homepage3.nifty.com/amigos/stopper/stopper-e.htm

* Danny M *

[Roger B]

If the angular contact bearings are the same size as the standard bearings they will certainly be easier to fit (I suspect that just fitting good quality versions of the standard bearings is probably enough  ).

I have attached some notes on the taper roller bearings and also a link to the collet extractor I made as another possible mod.

http://www.modelenginemaker.com/index.php?topic=2089.0

[spuddevans]

While you have the mill set up, this might be a useful addition http://homepage3.nifty.com/amigos/stopper/stopper-e.htm

* Danny M *

That is a handy mod, I already have a depth stop that I bought, but it doesn't have the feature of using a dial indicator which could be handy

If the angular contact bearings are the same size as the standard bearings they will certainly be easier to fit (I suspect that just fitting good quality versions of the standard bearings is probably enough  ).

You're probably right about fitting good quality bearings, but when I do it I probably will fit the AC bearings as it seems they are a worthwhile upgrade.


Tim

[bp]

I'm planning on a similar series of upgrades for my Sieg C3.  I was wondering which bearings to fit, so I had a look in my SKF book and found the following in the Basic load ratings columns

Deep Groove ball bearing 30 x 62 x 16 - Dynamic load rating 19500N; Static load rating 11200N
Angular Contact ball bearing 30 x 62 x 16 - Dynamic load rating 23800N; Static load rating 15600N
Taper roller bearing 30 x 62 x 17.25 - Dynamic load rating 40200N; Static load rating 44000N

I knew that this would be the general trend, but I didn't realise that the difference would be so great.  For my money there's no doubt that my new bearings will be taper rollers, even though they are not a simple swap.
cheers
Bill

[spuddevans]

Deep Groove ball bearing 30 x 62 x 16 - Dynamic load rating 19500N; Static load rating 11200N
Angular Contact ball bearing 30 x 62 x 16 - Dynamic load rating 23800N; Static load rating 15600N
Taper roller bearing 30 x 62 x 17.25 - Dynamic load rating 40200N; Static load rating 44000N

Interesting figures  Quite a difference between them all.

I'll have to consider whether going to the extra effort of fitting the taper bearings over fitting the AC bearings. A bit more research needed me thinks.

Thanks for posting those figures.

Tim

[Graham Meek]

Another addition for this lathe that some readers may find interesting and worthwhile can be found here.

http://www.modelengineeringwebsite.com/Mini_handwheel_1.html

My best regards
Gray,

[spuddevans]

I might just add that to my (growing) list of mods, thanks Gray


After some thought as to what "mod" to start on next (while I await delivery of brass) I started today by cutting a chunk-o-rust off in the bandsaw (thank goodness for bandsaws, I would really hate to cut this 63mm steel bar with a hacksaw)

I then popped it in the vice and used another offcut to make up for any unevenness/out-of-square-ness, and picked a roughing cutter. I'm now using the Ball-raced ER32 nut and I have to say that I am a convert. My collets are metric, and I used to have to juggle with trying to hold the cutter in place (it is 3/8" and the collet is 10mm) and keeping the spindle "lock" button held in while trying to tighten up the ER32 nut with a collet spanner. Now I can close up the collet nut just by hand until it grips, then finish off with a little tweak with the spanner. Well worth getting, I will be getting another one for my lathe.




After a short while I had somewhat distributed part of the steel all over the place



I need to rig up some swarf barriers




Anyway, after a little while and lot of swarf I ended up with this. Anyone guess what it is?





Maybe this will give you a clue.




A new foot for the tailstock, I'll show you a pic of the old and new together a bit further on. My dilemma was how to accurately position the hole for the clamping screw. The hole in the tailstock casting is about 12.7mm, so I routed in my scrap-box and found this




So I chopped the end off that was threaded, inserted a sharpened grub screw into it thus,




With the new "foot" in place I used my very expensive marking system to blue (black) it up. and popped the sharpened grub screw holder in place.




Worked pretty good eh?



Then by measuring from the end of the casting to the point of the grub screw and transferred that to the new foot. Then drilled 10mm through, and counterbored from the underside to give room for a nut and big enough for a socket to fit over it too. (although I'm toying with tapping it M12 and doing away with the nut altogether)

And here is the promised pic comparing old and new.





I also re-installed the lathe's original gibs and re-assembled the carriage, as the next parts of the cam-lock need to be turned.


Thanks for watching,

Tim

[arnoldb]

Good to see you back in the shop Tim, and great going on the improvements 

And yes - I agree with you on the ball-raced ER closer nuts - an absolute pleasure to use. 

Kind regards, Arnold

[spuddevans]

Thanks Arnold it feels good to be back making stuff again.


I got started today by rescuing a piece of very rusty steel (reclaimed from a bent earth spike dug out of the ground and carefully disposed by BT in my back hedge) and lopping off a short section. Then it was a simply a matter of taking very fine cuts (my re-assembled lathe is even more delicate as the old gibs are needing adjusting) to reduce it to 12mm.

Then I spent too long single point threading a 20mm section M12 ( this rare "Scrapbinium" is murdering my Hss threading tools)

Then I cross drilled the other end.

Anyway, on to (slightly) more interesting stuff.

In looking at the tailstock casting, nothing is even close to square.




The area around the hole for the clamping nut is especially bad, I stuck on a 6" rule with a thin magnet to illustrate the angle.





So after deciding that I needed to correct this, I then had to figure out a way of actually correcting it.

After a little thought I remembered that I had a small Angle plate thingy that I've never used up til today. So I dug it out and bolted it on my mill. Then with a little shimming and a couple of toolmakers clamps I ended up with this.




This may not seem very secure, actually it was rock solid. Even so, I took only light cuts, quite a few light cuts as I ended up removing about 1.6mm to get it squared up.




I also took some 8mm steel and offset turned a 12mm section near one end in the 4jaw (sorry no pic, will take one next time of all the componants of the tailstock camlock mod)

Then I got another small bit of 20mm square steel and poked a couple of holes in it.

Then I put all the bits together for a test, gave the sticking out bar of steel a twist with some pliers, and surprise surprise, the tailstock is locked solid.




All that's left to do is to cross drill the sticking out rod of steel (and shorten it) and attach a handle to it. (clear as mud I know, but hopefully it will all come clear in the next update)

The Idea for this kind of tailstock camlock system came from here :- http://warhammer.mcc.virginia.edu/ty/7x10/vault/Members/RickKruger/Tailstock/

Thanks for watching,

Tim

[spuddevans]

Finally I have completed one of the Mini-Lathe mods - the Tailstock Cam Lock.

I didn't have much left to do from yesterday. I started by marking up exactly where I wanted the little lock/release lever to be, then it was mounted in the Stevenson's ER32 block in the vice, and indicated the centre.




I know I've mentioned it before, but someone had asked me just how good the Ball-raced ER32 nut's are. I had to drill a 4.2mm hole for tapping M5, so I used a 5mm ER32 collet. Previously I would had to have used a C-spanner to close the collet enough to grip the drill, but with the ball-race-nut I was able to close it up with just my hand.


And I am also loving the Stevenson ER32 blocks, so easy for gripping round stock in the machine vice, and now I used it to make sure the shaft was kept square for tapping.




Then I parted off the cam to length. Then I threaded a short section of 5mm steel for the handle, assembled everything and then marked where to cut the handle, and then cut it and rounded the end off.

Here's all the componant parts. The cam has about 1.8mm of "lift" (or to be technically correct, "drop").




Then I started assembling. I used a couple of E-clips to stop the Cam from moving about, the back one requires turning the block 90degrees to fit.




Then the foot was screwed on, and after checking it was screwed in enough (and not too far) a locknut was tightened.




Here's it in "Unlocked"




and Locked




As you can see, there's not much in it, and it really locks solid with very little pressure.

I totally recommend doing this mod, it is so much better than the original method.


The brass needed for the tapered gibs arrived today, so after finishing up the Tailstock cam lock I disassembled the lathe's carriage. Then I mounted the new gib brackets on and placed it back on the ways. I was wanting to check if, and how much, clearance there would be between the brackets and the bed casting.




Looks like there's about 0.75-1mm of clearance at the front, and there's about the same on the back. So the plan is to mill the gibs down to about 0.25-0.5mm wider than the brackets. Because the front and back brackets have different depths, I marked up both ends of each gib to indicate which belongs to which.




Then I milled each Gib down to their respective widths, then, using a little round-over bit, I eased the 2 corners.




This was so that they wouldn't foul in the sharp corner of the bracket




And that was all I could get done as I had to go and make some nourishment.

Next up will be milling the tapers on the gibs.

Thanks for watching.
Tim

[ths]

Nice going Tim, it's good to see people improving their machines. Although I don't have your lathe (ML7 here), I can see that what you're doing will be a great improvement. The cam lock tail stock will be such pleasure to use, and I look forward to seeing how the tapered gibs work out.

Cheers, Hugh.

[spuddevans]

Thanks Hugh

So on with the tapers. I was going to leave the brass gibs un-tapered, but then figured that they would only give the same amount of grip as the factory originals.




So over to the mill and used the bracket to hold the gib for machining the taper, this ensures that the tapers will match each other perfectly.




I took off just the bare minimum to cut the taper, and then I couldn't help myself and just had to try it on the carriage. Still needs more taken off




I took it easy with the cuts, taking the time to check each time to make sure I didn't go too far. Each time I fitted it together I would score a pencil line where the edge of the bracket was




Next was drilling for the adjustment screw in the brackets. As the screw heads are 11mm diameter I decided to space them in from the ways by 6mm. I marked up the end of the bracket and put it in the vice. To get it vertical I used bog's trick of using a engineers square on the mill's bed and shining a light on the back of it. Shows up exactly when it's square.




Then to tap it M4 I clamped my tapping stand onto the mill and swivelled the head over. Worked a treat and made sure that there was no lateral flex on the taps.




In order to stop these brass gibs from moving out of place I want to put a couple of pins in each bracket and a corresponding groove in both gibs. I started off by measuring from the side of the gib that faces the bracket.




Then milled a 2mm groove in the centre of the gib




Then I poked a couple of 2mm holes in the bracket




Then a couple of short 2mm pieces were loctited in the holes




Then  it was on to the little groove that the adjustment screw fits into. I milled out a groove with a 3mm endmill, the screw head is 4mm thick, so I milled it to 3.8mm and then filed it to fit




It works!!




And it is about 1mm shy of the other end




Both done




Can I say smooth!!! It is like silk, and got better after a little oil ( always helps )

So another mod gets ticked off the list

Next up ...... I'm not sure. I'll see how the spirit moves me when next in the workshop.

Tim

[smfr]

Very nice job on the gibs there! 

Simon

[Roger B]

I agree, a very good piece of work   

[Stuart]

 Roger

A point if you can do it is a screw at the head stock end ,opposite the adjustment screw to apply tension against the adjustment screw to stop the gib moving in use , they can be loose one way and tighten up the other

The same as in a a SX3 mill Z ,and is the norm on full size machines

Stuart

[Graham Meek]

Hi Tim

You have made a nice job of those Gibs. One word of caution from my experience in rectifying two similar lathes for friends, the under face of the rear bedway is not always machined right into the corner where it meets the rear vertical face of the bed. Sometimes the gibs run on this un-machined edge and not the machined face.

There is an album below of the work I did on the two machines concerned, both were in identical condition and just over 12 months old.

http://www.model-engineer.co.uk/albums/member_album.asp?a=26835

My best regards
Gray.

[spuddevans]

Thanks Simon, Roger, Stuart and Graham

A point if you can do it is a screw at the head stock end ,opposite the adjustment screw to apply tension against the adjustment screw to stop the gib moving in use , they can be loose one way and tighten up the other

The same as in a a SX3 mill Z ,and is the norm on full size machines

That's a good suggestion, and it's not too hard to add a screw to the other end. That may be the next mod to be made. Heh!! A mod for a mod!!

One word of caution from my experience in rectifying two similar lathes for friends, the under face of the rear bedway is not always machined right into the corner where it meets the rear vertical face of the bed. Sometimes the gibs run on this un-machined edge and not the machined face.

There is an album below of the work I did on the two machines concerned, both were in identical condition and just over 12 months old.

http://www.model-engineer.co.uk/albums/member_album.asp?a=26835

Funny you should say that, I did notice that the carriage does tighten up a little at the headstock end. Hmm I thought I had left enough clearance (about 1.5-2mm) but maybe I need to skim half a mm off the thickness of the rear gib.


Thanks for those pics, they will be a good reference.

Can I ask if doweling the top-slide gibs brought about much improvement?

Tim

[Graham Meek]

Hi Tim,

Any Gib that is adjusted with set screws that are locked by nuts will benefit from dowelling. Especially if the adjusting set screw has more of a point on the end rather than a radius. The pointed end allows the gib to move fore and aft as the slide changes direction and rapidly wears the point down, usually dubbing the point over. Which of course makes future adjustment very interesting. Another bonus with the dowelled Gib is that should you need to remove the slide the Gib stays put and usually does not need readjusting. I did the Gibs on my Emco Maximat Super 11 just after I purchased the machine in 1986, I cannot recall having touched them since then, and my lathe has done a lot of work in the meanwhile.

My best regards
Gray,

[spuddevans]

Hi Gray,

Thanks for the info, I may add doweling the cross-slide gibs to the growing list of mods, they sound a worthwhile improvement


Tim

[ths]

Tim, I dowelled the top slide gibs on my ML7, and it has made a great difference. I must do the cross slide as well. Hugh.

[spuddevans]

Thanks Hugh, it sounds like a worthwhile mod 

Graham Meek had warned me that the milling on the underneath of the ways does not extend that far in, and to watch out for the gibs being too wide as they would jam up on the un-machined casting. He was dead right, I had left about 1.5mm gap on the back gib and about 0.75-1mm on the front gib, but noticed that when the gibs were snugged up with the carriage at the tailstock end, the carriage would jam up when about 4" from the headstock.

So I loosened the gibs enough to be able to smoothly push the carriage the full length of the bed, then put a light behind it and took a pic of the back gib




See how the rough casting has pushed the gib away. So I removed the gib and milled a little off just that corner (about 0.75mm wide by 0.5mm deep) Then replaced it and took another pic.




That's better, I am now able to snug up the rear gib and it runs smoothly the whole length. I also discovered that the front gib had the same problem, so I did the same for it and took 0.5mm x 0.5mm edge off the length that faces the casting.

If I was doing it again I would make sure there was at least 2mm gap between the casting and the gibs.


Another little issue that reared it's head in this mod is a little interference




The top half-nut catches on one of the cap screws holding the gib bracket on the carriage.

A simple solution was to thin the cap screw, which was a simple turning job.




Compared with a normal cap screw




That did the trick, the half-nut clears the new cap-screw.

I had considered adding a couple of "counter" screws to the other end of the gibs to lock the gibs, and I may well install one on the front gib. But if I put one on the rear I will lose about 1" of travel at the headstock end (it butts up to the backsplash) and if I am using a faceplate I may not be able to get close enough to it.

I think I may have another solution though, I'll let you all know when/if it works.


Anyway, on to the next mod.


I chucked up a 20mm steel bar




and turned down a 14mm section and then a 6mm section




I was amazed at how well the lathe cut with the new gibs, I was easily able to take a full 1mm deep cut per pass (2mm off the diameter)

Then I die-cut M6 thread and knurled a section.




Then it was cut off in the bandsaw and I repeated the process a couple more times. Then I reversed them and faced the cut end on all 3, and also cut a shallow groove (just enough to remove the knurl) on one (the one that was threaded M5)




And this is what they were all for




That should make changing the gear train a little easier, save having to dig out 2 different allen keys.


That's all for now, and sadly for the next couple of weeks I don't expect to get back into the workshop due to real life getting in the road of hobby-time.

Annoyingly my camera lens has started to fail, doing a google on the symptoms shows that it is a common enough problem, but at least there is a few "How-to" tutorials on fixing it (once the replacement part gets here from china). So hopefully that will arrive when I can get back into the workshop, then the camera can be the next mod!!

Thanks for watching,
Tim

[Graham Meek]

Hi Tim,

Glad I could be of help, these machines with a little TLC can be very good machines. Sometime back I added a screwcutting clutch to my friends Warco lathe, there are a couple of photographs below. The threading action makes machining threads on these lathes a walk in the park.

My best regards
Gray,

[spuddevans]

Glad I could be of help, these machines with a little TLC can be very good machines. Sometime back I added a screwcutting clutch to my friends Warco lathe, there are a couple of photographs below. The threading action makes machining threads on these lathes a walk in the park.

Thanks Gray, even just doing the gibs has improved it beyond belief.  That looks an interesting mod for screwcutting. I want to make a "Swing-up" threading toolholder to make threading easier, but the clutch looks good too. 


Tim