# Mega modifications for a mini lathe



## deadwat3r

hello. I am picking up a king Canada 7 x 12 mini lathe as soon as the store gets them in. I have some massive plans for this mini lathe but I could still use some advise and cautionary tales. I would like to build a bench similar to what hman had for his old 9X20 hopefully he has some input on this. I don't have a large space, in fact I only have a 3x5 foot area to really work with. the lathes over all dimensions are 32" x 11-1/2" x 13" I plan to make the bench about 36" x 18". I want the center of the hand wheel for the carriage to be at about 37-1/2" so I will have to take some measurements when the lathe arrives for the Hight. my father is a wood worker and I do it as a hobby. so I am confident I can build anything I dream up. I plan to build it entirely of construction lumber. some of the features I plan to incorporate into the bench are a 3 inch thick laminated bench top, rack behind the lathe with a 4 shelves one at the Hight of my back splash for oil cans, hex keys chuck key and a few wrenches, maybe a few other odds and ends. the next 2 shelves will be tipped at a 30 degrees towards the operator for quick change tool holders, I intend for the top shelf to be more of a cabinet that I can put inserts, change gears and other less frequently accessed items. I will be mounting some wood directly over head of the lathe to hang an led shop light. now that everything on top of the bench is covered lets move to the bench its self. I would like to use coolant on this lathe but im not sure how I will do it. im spit balling putting a drain in the factory chip pan running some pvc pipe to carry to coolant to a tank, but I don't know how big of a tank it should be. so I don't know where I can put it.  so some advise in this area would be appreciated. at the tail stock end of the lathe I will be putting some holes in the bench to hold tailstock accessories. drill chuck, dead center, live center and anything else you guys can think to list. moving to under the bench now, I would like to have some drawers to put things like calipers, micrometers, and what not. under that I will be putting in a shelf with tall narrow drawer with a couple of slide outs to keep chucks. I will also be storing the cases for all of my various crap I will be keeping in the stand. and the coolant tank will likely be down there too. now for the lathe its self. I would like to modify the tailstock to be camlock, or maybe buy a camlock tail stock if it is available. I would like to install locks on the compound, cross slide, and carriage. I will be installing a qctp, likely oxa in size unless I get any recommendations. I will be getting the tail stock dro that lms sells that replaces the dial. i would also like to do a touch dro setup that has a read out on the carriage and cross slide, as well as and rpm readout, and maybe an angle read out for the compound.  but have no idea where to start on that. I have also been working on the design and cad to make a bolt on quick change gear box for the lead screw and maybe for spindle speed as well so I can run the motor at what ever speed has the highest torque but that's a huge project that will likely never be completed. I already mentioned the coolant system, at some point I may try a solid tool post, even on a big lathe the compound is the weak link. I think that's all if you can think of any problems I would love to hear them along with any suggestions, or comments you have. thanks!


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## Z2V

First off, welcome to H-M, glad to have you. Reading your post, it sounds like you have a well thought out plan. Work your plan and see how it goes. You can always make adjustments and modifications as you go. Looks like your off to a good start when your machine comes in. Keep us posted on your progress. We love pics here. NO PICS it didn’t happen!!


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## petcnc

If your space is small you have to be creative on tools and storage for metals.
I am in a similar situation and I have Lathe and mill side by side.





Petros


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## deadwat3r

Z2V said:


> First off, welcome to H-M, glad to have you. Reading your post, it sounds like you have a well thought out plan. Work your plan and see how it goes. You can always make adjustments and modifications as you go. Looks like your off to a good start when your machine comes in. Keep us posted on your progress. We love pics here. NO PICS it didn’t happen!!



I will be making a youtube and documenting the whole process.


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## deadwat3r

petcnc said:


> If your space is small you have to be creative on tools and storage for metals.
> I am in a similar situation and I have Lathe and mill side by side.
> View attachment 315100
> 
> Petros


 I like that setup. how well does the milling attachment work? and  what is that chip guard you are using?


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## petcnc

The milling attachment is just crap! It is nice to mill plastic and aluminum nothing harder!
The guard is made by me just bigger to the original in order to retain the chips from flying around


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## deadwat3r

petcnc said:


> The milling attachment is just crap! It is nice to mill plastic and aluminum nothing harder!
> The guard is made by me just bigger to the original in order to retain the chips from flying around



that's a shame about the milling attachment. what did you make the guard out of?


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## petcnc

deadwat3r said:


> what did you make the guard out of?


I used an old computer's box, I cut the sheet metal and attached to the lathe no bending required.
I have made anumber of other mods to the lathe. See for example:
Lowering topslide of a mini lathe. here
Mini Lathe tailstock alignment here
Stiffening A Mini Lathe Bed here
 And a few other mods here

Overall the mini lathe is a fine machine to start with and gave me (still gives me) endless hours of fun
Petros


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## deadwat3r

petcnc said:


> I used an old computer's box, I cut the sheet metal and attached to the lathe no bending required.
> I have made anumber of other mods to the lathe. See for example:
> Lowering topslide of a mini lathe. here
> Mini Lathe tailstock alignment here
> Stiffening A Mini Lathe Bed here
> And a few other mods here
> 
> Overall the mini lathe is a fine machine to start with and gave me (still gives me) endless hours of fun
> Petros


i will check those out. also have you tried making qctp holders with the milling attachment.


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## ThinWoodsman

Pay particular attention to this one:


petcnc said:


> Stiffening A Mini Lathe Bed here


It deals with the most frustrating aspect of these lathes. I mounted mine to a wooden base and then filled it with concrete, but might bump that up to a rigid metal plate if I can get some of the other flaws fixed.

Speaking of which: pay attention to the gibs on the saddle. Slop in the saddle is probably the biggest weakness of these lathes, even more than bed twist. And you do yourself no favors if you lock the carriage and use only the compound to feed. You're gonna need a fix for those gibs.

I'm considering making a Gibraltar-style toolpost to use in place of the compound and that crap (non-OXA) QTCP supplied by Micromark: just a big hunk of metal (likely machined from that 2" cast iron round that Hobby Metal Kits provides) with maybe 5/8" for tool shanks, using shims or sleeves to get tools to height.


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## homebrewed

Welcome to H-M!

The saddle slide plates (some folks refer to them as gibs) definitely are one of the weaker design point of these lathes.  It's pretty easy to improve that by getting rid of the OEM jack screws and using shims to get the running fit you need.  That mod was one of the best and easiest I've done to my mini lathe.  You don't need to get all fancy and do the tapered gib thing, and it really improves the overall rigidity.

If you replace the compound with a riser block, don't throw or trade the compound away.  You still will need it for cutting threads or short tapers.


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## deadwat3r

ThinWoodsman said:


> Pay particular attention to this one:
> 
> It deals with the most frustrating aspect of these lathes. I mounted mine to a wooden base and then filled it with concrete, but might bump that up to a rigid metal plate if I can get some of the other flaws fixed.
> 
> Speaking of which: pay attention to the gibs on the saddle. Slop in the saddle is probably the biggest weakness of these lathes, even more than bed twist. And you do yourself no favors if you lock the carriage and use only the compound to feed. You're gonna need a fix for those gibs.
> 
> I'm considering making a Gibraltar-style toolpost to use in place of the compound and that crap (non-OXA) QTCP supplied by Micromark: just a big hunk of metal (likely machined from that 2" cast iron round that Hobby Metal Kits provides) with maybe 5/8" for tool shanks, using shims or sleeves to get tools to height.


That was the first one i checked! Any suggestions for those gibs? Anyone? Keep me in the loop of that tool post. The very little info i could find is very interesting.


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## deadwat3r

homebrewed said:


> Welcome to H-M!
> 
> The saddle slide plates (some folks refer to them as gibs) definitely are one of the weaker design point of these lathes.  It's pretty easy to improve that by getting rid of the OEM jack screws and using shims to get the running fit you need.  That mod was one of the best and easiest I've done to my mini lathe.  You don't need to get all fancy and do the tapered gib thing, and it really improves the overall rigidity.
> 
> If you replace the compound with a riser block, don't throw or trade the compound away.  You still will need it for cutting threads or short tapers.


Removing the screws and shimming it doesn’t sit right in my head. Could you explain more? And i wont throw it out. Unless i just all together make a new one.


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## ThinWoodsman

deadwat3r said:


> Removing the screws and shimming it doesn’t sit right in my head. Could you explain more? And i wont throw it out. Unless i just all together make a new one.



As shipped, the gibs under the saddle attach with 3 screws that go through the gib and attach to the saddle, and two screws that go into threaded holes on the gib. These two screws are jack screws: they work by going through the gib and pushing it *away from* the saddle. The other screws pull the gib *towards* the saddle. It is very fiddly, to say the least.

There is a photo on mini-lathe.com that hopefully clears things up.

I agree with getting rid of the jack screws and just using shims: put shim stock between the gib and the saddle until it is just right.

When I spend more time with my 7x16 (and to be honest, I somewhat hate the thing but do view improving it as a challenge), I will probably mill a part that is put in place of the gib/side plate, and have it house a proper gib, perhaps bolted in from the side instead of from the bottom so gravity isn't fighting you during adjustment.  Still just an idea though. There any many ideas out there on how to fix the gib problem. There's a chapter in David Fenner's book Mini-Lathe Tools and Projects that covers the three most popular approaches.


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## RJSakowski

If possible with your setup, position the lathe so there is free space to the left of the lathe.  This is so you can insert long bars through the spindle.  You will also want space to be able to change gears, belts, etc.  The tailstock will only extend past the bed by a few inches at most.


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## savarin

This gentleman has a heap of improvement mods for the chinese mini lathe








						Steve Jordan
					

I have worked in the Aerospace Industry for 27 years in these skills...CNC & centre lathe setting and machining, assembling & testing hydraulic, pneumatic an...




					www.youtube.com


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## deadwat3r

RJSakowski said:


> If possible with your setup, position the lathe so there is free space to the left of the lathe.  This is so you can insert long bars through the spindle.  You will also want space to be able to change gears, belts, etc.  The tailstock will only extend past the bed by a few inches at most.


thanks for the advise. that was my plan. I do have a good bit of experience on large lathes at work.


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## deadwat3r

ThinWoodsman said:


> As shipped, the gibs under the saddle attach with 3 screws that go through the gib and attach to the saddle, and two screws that go into threaded holes on the gib. These two screws are jack screws: they work by going through the gib and pushing it *away from* the saddle. The other screws pull the gib *towards* the saddle. It is very fiddly, to say the least.
> 
> There is a photo on mini-lathe.com that hopefully clears things up.
> 
> I agree with getting rid of the jack screws and just using shims: put shim stock between the gib and the saddle until it is just right.
> 
> When I spend more time with my 7x16 (and to be honest, I somewhat hate the thing but do view improving it as a challenge), I will probably mill a part that is put in place of the gib/side plate, and have it house a proper gib, perhaps bolted in from the side instead of from the bottom so gravity isn't fighting you during adjustment.  Still just an idea though. There any many ideas out there on how to fix the gib problem. There's a chapter in David Fenner's book Mini-Lathe Tools and Projects that covers the three most popular approaches.



ok thank you. I will keep that in mind and add it to my list of books to buy.


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## deadwat3r

savarin said:


> This gentleman has a heap of improvement mods for the chinese mini lathe
> 
> 
> 
> 
> 
> 
> 
> 
> Steve Jordan
> 
> 
> I have worked in the Aerospace Industry for 27 years in these skills...CNC & centre lathe setting and machining, assembling & testing hydraulic, pneumatic an...
> 
> 
> 
> 
> www.youtube.com


I have watched a few of his videos. to be honest I find he gives me a headache. but I will try to suffer through if I run into major problems.


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## homebrewed

Make sure to spend some time and effort on the tailstock, too.  On this class of machine they are notorious for being problematic -- not aligned properly, unstable base (causing wide variations in position) and so on.  I found it most expedient to do some mill work to address the issues mine had, but a lot can be done with shims if you don't have the luxury of a mill sitting next to the lathe.  Once aligned, I'm damned if I'm going to set the TS over to cut a taper, but that's just me.....

One alternative (and one I also have done) is to mount a drill chuck on your toolpost.  I did it with a chuck that is mounted using a 1/2" thread.  I had a boring bar holder that accepts 1/2" diameter shanks so it was -- almost -- a no-brainer.  It can be real nice if you start with a small-diameter drill and work your way up, because the tailstock usually has to be moved back partway through the operation to accommodate longer drills.  Not the case with a TP mounted chuck.  However, that also is when I discovered my problem with the saddle gibs AKA slide plates -- the whole saddle would tip up and back when I applied pressure to the drill.  One things leads to another.

BTW, if you're enlarging holes in brass, beware -- conventional drill bits will self-feed, or, worse, try to and then break.  This problem is most apparent when using the toolpost-mounted chuck because there's nothing to prevent it from happening.  Trust me:  I know this for a fact.  It's scary to see your drill bit sort of "unwind" when it catches, because you know it's THAT close to just snapping apart from the stress.  And since a chuck mounted in the tailstock is just using the taper to hold it in place, it could be pulled out of the tailstock......so the fact that the TS has a feed screw isn't much comfort, either.


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## deadwat3r

homebrewed said:


> Make sure to spend some time and effort on the tailstock, too.  On this class of machine they are notorious for being problematic -- not aligned properly, unstable base (causing wide variations in position) and so on.  I found it most expedient to do some mill work to address the issues mine had, but a lot can be done with shims if you don't have the luxury of a mill sitting next to the lathe.  Once aligned, I'm damned if I'm going to set the TS over to cut a taper, but that's just me.....
> 
> One alternative (and one I also have done) is to mount a drill chuck on your toolpost.  I did it with a chuck that is mounted using a 1/2" thread.  I had a boring bar holder that accepts 1/2" diameter shanks so it was -- almost -- a no-brainer.  It can be real nice if you start with a small-diameter drill and work your way up, because the tailstock usually has to be moved back partway through the operation to accommodate longer drills.  Not the case with a TP mounted chuck.  However, that also is when I discovered my problem with the saddle gibs AKA slide plates -- the whole saddle would tip up and back when I applied pressure to the drill.  One things leads to another.
> 
> BTW, if you're enlarging holes in brass, beware -- conventional drill bits will self-feed, or, worse, try to and then break.  This problem is most apparent when using the toolpost-mounted chuck because there's nothing to prevent it from happening.  Trust me:  I know this for a fact.  It's scary to see your drill bit sort of "unwind" when it catches, because you know it's THAT close to just snapping apart from the stress.  And since a chuck mounted in the tailstock is just using the taper to hold it in place, it could be pulled out of the tailstock......so the fact that the TS has a feed screw isn't much comfort, either.


I was wondering about the tail stock. I will make sure its running right as well. The qctp set i want comes with a mt2 block. I was planning to use it. At work we only machine plastics really, so im very familiar with drill bits binding. Carbon/glass filled nylon will happily snap a one inch drill if you are not on your A-game. Im thinking i will pick up some polypropylene, uhmw, acetal, unfilled nylon, hdpe, some 6061 aluminum, some 360 brass, and some 12l14. All one inch diameter for testing.


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## deadwat3r

well some of the wood for the stand came home today, plus tapered roller bearings arrive early this week. its a start to the modifications at least.


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