# Milling attachment for a mini lathe



## sploo (4 Aug 2020)

I have one of the ubiquitious SIEG mini lathe clones (a Clarke CL300M) and would find it useful to have a little bit of milling capability. I picked up an old Myford vertical milling slide from eBay, and made a plate to interface the slide to the lathe.

After removing the compound slide I drilled and tapped a single extra hole to the cross slide (top of image):







With no metal cutting gear (or mill) I hacked out some 10mm mild steel plate, and drilled and tapped a series of holes to hold the plate onto the lathe, and provide three locations for the slide:






The mini lathe has very little slide travel, so the three different locations hopefully give me some options for different parts:
















The two locations with the slide facing the headstock were chosen to allow the slide to travel to its lowest position:






I have now tried a bit of milling... and understand why milling machines are best delivered in the 1000kg+ department... it works, but the lathe's going to need more mods to lock the slides that aren't supposed to move.


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## AES (4 Aug 2020)

Excellent mod sploo, well done. But just as you say, one of the main "problems" with all the Mini Lathes is lack of rigidity, especially if trying to mill stuff (DAMHIKT)!!!

For this reason I suggest you look at the link below, which significantly increases carriage/ways stiffness, AND adds a decent carriage lock (without relying on the engaging the self-act).

I've had problems with milling on my Mini Lathe and will be doing the mod shown in the link below as soon as I "getaroundtoit". Meantime, if you do your lathe first let me/us know how it goes please:

https://www.youtube.com/watch?v=xvc0-QT ... ex=8&t=13s

HTH. Cheers


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## sploo (4 Aug 2020)

AES":16nsg3jd said:


> Excellent mod sploo, well done. But just as you say, one of the main "problems" with all the Mini Lathes is lack of rigidity, especially if trying to mill stuff (DAMHIKT)!!!
> 
> For this reason I suggest you look at the link below, which significantly increases carriage/ways stiffness, AND adds a decent carriage lock (without relying on the engaging the self-act).
> 
> ...


Many thanks. As it happens; the plate is essentially copied from one of Steve Jordan's other videos, and, in having to remove the rear guard, I'm going to do his mod with the studs and long nuts.

I'd got all the gibs nicely tightened; such that lathe work has been really pleasant recently, but attempting a milling operation caused so much vibration that at one point the lathe cr*pped out a random bolt :shock:. It turned out to be one of the bolts on the underside of the cross slide.

That slide is a bit of pain to adjust (exactly as he details in the video you've linked above), so perhaps some shim stock, studs, and nylock nuts would be a good first upgrade.

If you look at the first image of my original post you'll see that, unfortunately, the main plate of the cross slide on my lathe is scalloped out between the ways, so there's nowhere for the two screws that he uses for the plate that goes in between the ways. However, I'd already started making strips to bridge the two sides, and the part I was machining was essentially a short version of what he's made, for use as a lock:






Maybe I'll instead do his longer version - which of course will also be easier from two separate plates, rather than trying to mill a larger block.

I just need to get myself some shim stock I guess. Or maybe a £200 desktop Bridgeport, that goes from 10kg (for easy lifting) to 500kg at the push of a button...


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## AES (4 Aug 2020)

OK sploo, thanks for the extra info.

I must say that I gave up on that (IMO) daft original idea of those funny plates under the ways to "fix" the carriage with a correct tolerance between stuck fast and free to slide. I just threw them away and used shims. BTW, shim "stock" is fairly easy to find - No. 1 you can cut up Coke (& similar) cans - that's ali of course, but it works; No. 2 if you've got a decent model shop near you they should stock 12 inch square sheets of brass, tinplate, and nickel silver in various thickness from 5 thou (inch) thickness & above.

But if you're really pushed and don't need "sq yards" of it (!) drop me a PM and I'll put a couple of bits of the required thickness/es in the post to you.

Cheers


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## sploo (4 Aug 2020)

AES":2os2qluf said:


> OK sploo, thanks for the extra info.
> 
> I must say that I gave up on that (IMO) daft original idea of those funny plates under the ways to "fix" the carriage with a correct tolerance between stuck fast and free to slide. I just threw them away and used shims. BTW, shim "stock" is fairly easy to find - No. 1 you can cut up Coke (& similar) cans - that's ali of course, but it works; No. 2 if you've got a decent model shop near you they should stock 12 inch square sheets of brass, tinplate, and nickel silver in various thickness from 5 thou (inch) thickness & above.
> 
> ...


Thanks. I'd just done some searching and was shocked at the cost of brass shim stock - I guess you're paying for the tolerances (or maybe the manufacturing needed to make it). Dunno. Anyway, I've ordered a few different thicknesses, having checked the current gap on the lathe (between 12 and 25 thou).

I've also ordered the steel stock to made the longer "lock" that goes between the ways.


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## AES (4 Aug 2020)

Yeah, shim stock isn't cheap, and I don't really know why, though I guess hot rolling it to fine tolerances (which is what I think they do) MAY be at least part of the answer.

One other "cheapo trick" apart from Coke tins you can try is to cut up empty food tins (if they haven't got those annoying corrugated sides), or things like motor oil (& similar) cans. All those are tin plate of course and are somewhat thicker than Coke (ali) drinks cans.

Anyway, let me/us know how you get on please. I definitely shall be doing that carriage mod myself - as said, "one of these days" (!) ;-)

Edit for P.S. In the last of your pix posted above it looks like you're using a collet chuck for the milling cutter. What sort may I ask? I'm currently considering a cheapo Chinese (Banggood ER 32) set. Up to now I've been using a 4 jaw self-centering chuck but feel a "proper" collet chuck set up would be better - along with a more rigid set up of course. Any comments/experience please?


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## TFrench (4 Aug 2020)

I have the perfect solution for you. I picked it up last weekend. Bolt your mini lathe to the table, and hey presto. A whole world of 4 axis machining at your disposal!
Edit: having had the idea, I now really want to try it!





Sent from my SM-G973F using Tapatalk


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## AES (5 Aug 2020)

Thanks a LOT for that idea TF!!!!!!!!!!!! ;-)


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## RichardG (5 Aug 2020)

A quick hint, look for old sets of feeler gauges at car boot or tool sales. I find this a great source of shim material for next to nothing plus they have nice labels on! 

Richard


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## AES (5 Aug 2020)

Yup, good point, thanks.


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## sploo (5 Aug 2020)

AES":3my4ivcs said:


> Anyway, let me/us know how you get on please. I definitely shall be doing that carriage mod myself - as said, "one of these days" (!) ;-)


I got a bit more done last night - you can see the bar I added to the right side of the cross slide (it required a couple of M4 tapped holes to be added). Underneath is the (terrible) "T" nut I milled on the lathe. The carriage can be locked using the screw. I was planning on turning a knob or lever, but that's a job for another day:






I realised that there's a couple of M6 tapped holes on the top of the slide on the left hand side - I believe for the travelling steady. I've experimented with a piece of 25x6mm bar; which looks to be reasonably secure. With some extra work that should allow me to run a longer "T" bar under the carriage as per Steve Jordan's mod.

The only problem is that the width of the strip would now prevent the milling slide from lowering fully, so I might have to modify the strip at some point:






Finally, I turned a couple of knobs and glued them to some tubing I had. This is the "stud" mod for easy removal of the rear guard:


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## sploo (5 Aug 2020)

AES":25lydmi8 said:


> Edit for P.S. In the last of your pix posted above it looks like you're using a collet chuck for the milling cutter. What sort may I ask? I'm currently considering a cheapo Chinese (Banggood ER 32) set. Up to now I've been using a 4 jaw self-centering chuck but feel a "proper" collet chuck set up would be better - along with a more rigid set up of course. Any comments/experience please?



It's the 100mm ER40 lathe collet chuck from Arc: https://www.arceurotrade.co.uk/Catalogu ... let-Chucks with one of their part machined back plates: https://www.arceurotrade.co.uk/Catalogu ... late-Plain

Originally I got it with the intention of being able to move it between a couple of different lathes (I have a larger woodturning lathe). With hindsight, an MT3 ER32 chuck might have been better (less work to set up, and the ER32 collets are a fair bit cheaper than ER40).

Investing in an ER system isn't cheap, but highly recommended. It makes turning rod stock really simple, and obviously you can hold cutters.


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## sploo (5 Aug 2020)

TFrench":3poaqsfx said:


> I have the perfect solution for you. I picked it up last weekend. Bolt your mini lathe to the table, and hey presto. A whole world of 4 axis machining at your disposal!
> Edit: having had the idea, I now really want to try it!
> 
> 
> ...


*LOL* I'm very jealous. I could (just about, maybe) fit one of those "proper" milling machines in the garage, but getting a 300kg planer/thicknesser in there a few years ago scared me silly (sloping drive, trying to winch it off the tail lift of a Luton). The idea of trying to set up something in the 1000kg+ range is a bit daunting.

I guess that's the problem with metalwork - you really do need mass in the machinery, so anything "serious" is going to be a big job to install.


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## AES (5 Aug 2020)

Yeah, dead right sploo. From the looks of TF's pix, the motor alone from that girt big thing would hardly fit in my cellar, let alone all the rest of it! And getting it down the stairs? Forget it ;-)


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## sploo (5 Aug 2020)

AES":34md9wh2 said:


> Yeah, dead right sploo. From the looks of TF's pix, the motor alone from that girt big thing would hardly fit in my cellar, let alone all the rest of it! And getting it down the stairs? Forget it ;-)


Oh it'd go down the stairs all right. Just not at the pace or angle you'd planned :mrgreen:


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## MusicMan (5 Aug 2020)

TFrench":3qlusvx7 said:


> I have the perfect solution for you. I picked it up last weekend. Bolt your mini lathe to the table, and hey presto. A whole world of 4 axis machining at your disposal!
> Edit: having had the idea, I now really want to try it!
> 
> 
> ...


Tom, that's tool porn. Can't wait for your restoration thread!
Keith


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## TFrench (5 Aug 2020)

That one will just be a clean up and move on Keith, not a keeper. It'd be like swapping a ferrari for a ford focus if I was to get rid of one of the Deckels for it. I cleared a workshop a couple of weekends ago - no one else was daft enough to want to do it I think. Most of the stuff was movable with a sack barrow, but the bridgy and a biggish harrison lathe were the sticking points. The landrover and trailer fitted down the access with millimetres to spare, then we just winched them on the trailer on metal sheets to slide. Wish I'd got photos!
Sorry for the thread hijack!


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## sploo (5 Aug 2020)

TFrench":1s99yzii said:


> That one will just be a clean up and move on Keith, not a keeper. It'd be like swapping a ferrari for a ford focus if I was to get rid of one of the Deckels for it. I cleared a workshop a couple of weekends ago - no one else was daft enough to want to do it I think. Most of the stuff was movable with a sack barrow, but the bridgy and a biggish harrison lathe were the sticking points. The landrover and trailer fitted down the access with millimetres to spare, then we just winched them on the trailer on metal sheets to slide. Wish I'd got photos!
> Sorry for the thread hijack!


No problem at all. Remember that forum rules dictate that a thread hijack means the OP owns all referenced machinery; so if you'd just clean up the BP and the Harrison and drop them off at my place :mrgreen: 

Amusingly I needed to turn a taper this evening... about 80mm in length... the mini lathe travel will only do ~65mm. I need a bigger lathe!


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## sploo (14 Aug 2020)

Updates...

I made the longer "t" piece that fits between the rails, as per Steve Jordan's video.

The right side of the main slide still has the bar I added, and on the left I've modified the strip I installed earlier:







Unsurprisingly, that "t" plate is much better than the shonky piece I milled myself. I had planned to turn a knob to use as a locking screw, but the hex bolt I'm using at the moment is easy to access with an allen key and works well:







On the left side there's a gap between the "t" piece and my strip. Eventually this will get some brass shims and will be tightened to improve the rigidity on the slide: 







For an unrelated project, I needed to mill some 14x14 keyways down to 14x12. Lacking any parallels or a proper vise, I used another bit of keyway stock and an old drill vise:






That worked well fairly badly, up until the point the bit ripped the pieces out of the vise; chipping the brand new carbide cutter in the process . I changed out to a thinner "parallel", and used a smaller cutter. It took ages, and there's plenty of chatter, but it did successfully do the milling: 






It (only just) looks worse in the photo than it actually is.

I'm now in the process of making a small two piece vise to fix on the vertical slide, and have ordered some budget parallels.


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## AES (14 Aug 2020)

Thanks for the update sploo. Watching with great interest, I haven't even started Steve Jordan's Carriage mods yet (LOTS of "other stuff" going on right now).

Gonna try the new bookmarking system for this, thanks again (and sorry about the cutter - have you got a green wheel)?


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## TFrench (14 Aug 2020)

HSS square toolbits make handy parallels if you're stuck for some.


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## sploo (15 Aug 2020)

AES said:


> Thanks for the update sploo. Watching with great interest, I haven't even started Steve Jordan's Carriage mods yet (LOTS of "other stuff" going on right now).
> 
> Gonna try the new bookmarking system for this, thanks again (and sorry about the cutter - have you got a green wheel)?


What's a green wheel (other than a wheel... that's green)?


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## sploo (15 Aug 2020)

TFrench said:


> HSS square toolbits make handy parallels if you're stuck for some.


Good idea. I'd initially used a bit of the 14x14 keyway stock, but I do have some 8x8 and 10x10 HSS stock for lathe cutters.

My budget set of parallels turned up today though, so hopefully I won't need to resort to raiding the lathe tool bin!


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## TFrench (16 Aug 2020)

sploo said:


> What's a green wheel (other than a wheel... that's green)?


Green ones are for carbide


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## AES (16 Aug 2020)

Yes, Thanks TFrench!

Sorry sploo, having visitors this weekend and only just seen your Q. Just as TFrench says, "green grit" grinding wheels can be had in a variety of diameters, thicknesses, bores,and grits - just like any other grinding wheels. The difference is that "green wheels" have a "special stone"/"special glue" (dunno which, may well be both) which means that you can grind carbide with them - I have one for just touching up some carbide tools.

The reason I mentioned green wheels in response to your last post about a broken milling cutter is that although I don't know which cutter you broke and what exactly is broken, it just MAY be possible for you to reclaim an expensive tool with careful use of a green wheel. In normal sizes they're not all that expensive.

If you do buy one don't forget the "string loop trick" to make sure you don't install a cracked wheel - especially if buying online.

If you need more info about string loops, etc, there's a very old post by me about grinding wheel safety (which I think was a sticky at onetime) but if you can't find it, post here or PM me and I'll illuminate further


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## sploo (16 Aug 2020)

Ah. Got it thanks. I don't have a wheel, though I have the Sorby Pro Edge. I did wonder if it might be possible to regrind the cutter - though a lot would have to be taken off.


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## sploo (18 Aug 2020)

More progress... some good, some not so good...

The two piece vise came together pretty well:













There are two pairs of holes in each main block as I'm limited for space/t-slot locations; so it gives me a bit more flexibility around the jaw opening size:







And holding an ER collet block (the cap head bolt I had isn't long enough; hence changing to a hex head bolt):







The first test was cutting a vee grove in some keyway stock, using a D bit cutter I made from some silver steel (that has been heat treated for hardness):







Surprisingly... it works! The key steel I had is definitely harder than mild steel, and despite a bit of chattering, the piece (and even the DIY cutting bit) survived:







What are those little pieces for I (don't) hear you ask? Well; they're for a tap wrench (as per a This Old Tony video). I'd previously made the handles on the lathe:







And... having done all the hard stuff... I'd clearly screwed up drilling the holes, so it doesn't fit together :







Anyway, the vise looks quite nice on the vertical slide. The main problem is that it puts a lot of pressure on the slide (such that raising and lowering the slide gets difficult when the vise is holding something with sufficient force). I may need to make a steel plate for the vise to sit on (which itself will then go on the slide). The main problem (other than the chatter) is the limited space; I'm finding it hard to position parts such that they can be cut. Really I need a proper mill.


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## AES (18 Aug 2020)

Nice looking pieces of work sploo. Well done Sir (Tried to insert the clapping hands there - where's THAT one gone?).

And even though I (still) haven't started the Steve Jordan mod and have so far only done very little milling, I DO understand your concerns re lack of space on the Mini Lathe mate! but there's precisely NIL chance of the Chez AES budget including any such "looksery, pure looksery Lad").


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## sploo (18 Aug 2020)

AES said:


> Nice looking pieces of work sploo. Well done Sir (Tried to insert the clapping hands there - where's THAT one gone?).
> 
> And even though I (still) haven't started the Steve Jordan mod and have so far only done very little milling, I DO understand your concerns re lack of space on the Mini Lathe mate! but there's precisely NIL chance of the Chez AES budget including any such "looksery, pure looksery Lad").


I've got some more of the keyway steel on order to have another go at the two little blocks. Since I did the above, I have managed to mill a small adapter for a friend's screwdriver out of 10mm silver steel. I guess I have made life hard for myself by so far only trying to mill some moderately high carbon steels (they seem to be pretty hard).

As for a milling machine... I don't really know where to start. Ignoring the "proper" 1.5 ton+ machines, there are loads of options, but most of the ~£700 SIEG clones look a little weak.


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## sploo (23 Aug 2020)

Key steel turned up and I had another go at making the two blocks; much better this time.

Rather than using an end mill, I tried reducing the 14x14 steel down to the required 14x12 cross section using my boring head as a fly cutter. I have some carbide boring tools but given carbide's dislike of interrupted cuts I found a piece of HSS tool steel that I was able to clamp securely. Surprisingly; it went very well:







Next job was to cut the vee groves, again using my homemade 'D' bit:







That went OK, so I rigged up a simple jig to let me pivot the pieces on by disc sander, for rounding over the corners:







Cleaned up and finished:











Not exactly to This Old Tony standards, but given it was all done on a Chinese mini-lathe (by someone with no previous metalworking experience) I'm pretty happy. It even works!


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## AES (23 Aug 2020)

" Not exactly to This Old Tony standards, but given it was all done on a Chinese mini-lathe (by someone with no previous metalworking experience) I'm pretty happy. It even works!"

And so you should be Sir. Well done.


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## sploo (23 Aug 2020)

AES said:


> " Not exactly to This Old Tony standards, but given it was all done on a Chinese mini-lathe (by someone with no previous metalworking experience) I'm pretty happy. It even works!"
> 
> And so you should be Sir. Well done.


Many thanks. Just don't look too close at the finish, or the fact the knurling turned out different on the two handles...


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## TFrench (23 Aug 2020)

sploo said:


> Many thanks. Just don't look too close at the finish, or the fact the knurling turned out different on the two handles...


We're all our own harshest critics. It looks fantastic!


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## sploo (2 Sep 2020)

Minor update; I drilled and tapped a set of holes on an offcut of 10mm steel plate, for use on the vertical slide. The plate is held onto the slide with countersunk bolts in "T" nuts, and the two rows of tapped holes give a much large range of clamping options for the two piece vice. The unused set of countersunk holes in the image below are for mounting the plate horizontally on the slide (should I have something that I'd like to clamp vertically in the vice). 

I've found it's also quite good at taking the clamping force of the vice; such that it's not stressing the vertical slide bed (which was previously making it hard to turn the handle for raising and lowering the bed).


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