# Bazmak-Making a turret/capstan for the minilathe



## bazmak (May 7, 2017)

Early days yet,but I have a question early.What gear size is the rack and pinion ?
As you all know thoughts start flying about in your head,started with a pencil and back of a matchbox.Basic idea at this early stage is to fabricate a tailstock carriage with top plate and apron similar to the main one and drive off the 
existing rack with gears and pinion.If I can get right then I cn build up a
tool turret from there.If you read one of my earlier threads I converted a wood lathe to metal by fabricating a carriage with a central leadscrew.This carriage would not be much different or difficult.
The idea being a large 3 spoke handwheel to drive the turret thru 2 mod1 changegears (surplus to first lathe) to get the direction correct.I will have to make a new pinion as the original,hence the initial question I will replace the deleted photos and try to get them in a semblence of order. I will be unable to take new photos as i sold the mini capstan lathe and bought a Myford which i have on a current thread.I do however have all the original photos which i will repost if Mike makes contact or anyone else shows interest


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## goldstar31 (May 7, 2017)

Forgive me but my Guessing Stick   was handed to my son years ago and I've long given up my doodle pad which was a cigarette packet.
So I have to write what the history book says- and damn those critics about using the past as a suggestion.

Cleeve simply used the Empirical Formulae of using a rack from Myford proportions but after a series of earlier efforts on older m\achiness, skewed the feed. The rest of the panjandrum was fabricated.

I have a Mk1 Clarkson T&C but for the life of me, I've never explored but I made the baby one which is the Stent and later got a welded one. Clearly, there was a rack and pinion and it dawned on me that it was actually a Myford rack with a 20DP gear on both! I still have the fabricated little Stent and it works!

So Metric????. I had a 918( actually a 9180 with a Myford nose) and I have no doubt that it was a 3mm leadscrew and 1DP cogs.

So lashing it all together, I would say 'use what you have or can make'

Leverage is simple- make the lengths of the 'levers' to suit your personal equation.

Does this help, please?

Now I'm on the look out for a 3MM leadscrew  and half nuts-- for a Myford ML10.  Any bright sparks to help?

Cheers

Norm


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## goldstar31 (May 7, 2017)

Hooray for 'Pelmanism' for unearthing my old wartime schoolboy French, you want 'Tour en general- OneDrive' for various capstan configurations. 

N


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## MachineTom (May 7, 2017)

A thought, I have a turret that fits into the mt2 taper of the tail stock. Not a rack pinion drive but a start. I also have a complete turret sliding assembly, handwheel. Fits a Harrison M-300 . Can be adapted to fit others. But you need to have a lathe swing of 12inch plus.


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## goldstar31 (May 7, 2017)

MachineTom said:


> A thought, I have a turret that fits into the mt2 taper of the tail stock. Not a rack pinion drive but a start. I also have a complete turret sliding assembly, handwheel. Fits a Harrison M-300 . Can be adapted to fit others. But you need to have a lathe swing of 12inch plus.


 
The Sparey I mentioned, fits into the No2MT tailstock- originally a Myford ML7 which swings 7"

The Ken Metcalf- I have the drawings etc somewhere- was designed for the ML7.
What has to be mentioned is the need to bore each station in line with the spindle. 
So Baz has to really have something  to 'line up' with his own lathe.

Don't be offended please- I'm simply clearing up possible misconceptions.
Or the reason why I have done nothing to mine- yet:hDe:

Regards

N


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## bazmak (May 7, 2017)

Thank you boys.I have seen the capstan attachments that fit the no2 MT
but don't like them + they will take up room on my limited 14" centres
As with the model shaper my memories take me back to operating the old Ward 7 capstan lathe and the good feeling of the solid clunck as the turret swung.Would like auto rotation but at this stage only have in mind manual
Initial thoughts were to make the carriage and rack/pinion drive first to 
get it all working,before thinking too much about the turret
I thought that lining the stations up would be easy,just drill and bore from the lathe headstock when each position is set.Please correct me if I am wrong
Meanwhile just nipping out to get a few pieces of steel to make a start
Regards Barry


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## bazmak (May 8, 2017)

Well I have made a start.Hacksawed of a piece of 100x20mm HRS
11 mins saved me $6 cutting charge.Cleaned and sqared up all faces
and cut the 90oV with an endmill.Decided to get the fit much nearer before
doing any further machining,so spent an hour fileing and scraping till almost there.Took further very light skims using the V as a datum 
Must say it was easier than i thought it would be and far superior to a cast one


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## bazmak (May 9, 2017)

Well after an enjoyable 4 hrs in the shed I have finished the basic carriage
and apron.I made 2 no stepped gibbs and fitted.Just a couple of thou play for now,too early to bed and scrape at this stage.Also cut down and machined
a piece of 90x90x10 rs angle,also fitted.All fixings are cap screws from the top
so I have easy access for adjustment or dismantling.Now I have the basic frame the fun begins.Next will be the pinion.Will have to make one to the same dims as existing.I was going to use 2 mod 1 changegears to drive from the handle to the pinion,with 1 gear fixed to the pinion,but have decided to try and make the pinion and gear as one unit.The pivot shaft I have in mind to turn 
slightly eccentric so I have adjustment for centres.Should be interesting but
my head is going round in circles.Thats what happens when you do a bit at a time with no drawings


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## bazmak (May 10, 2017)

Next I decide to make the pinion.After all those hours playing about with
gearcutting I am now reaping the rewards.Took off the rack and apron from the mini lathe and using a couple of different methods I measured the rack
at 4mm pitch.The rack was located on the mini lathe hard towards the headstock and had approx. 50mm unused,so redrilled and moved towards the tailstock approx. 45mm to give more use where its needed
Next I measured the pinion and came up with 11 teeth and mod 1.25
Decided to make the new one 12 teeth for obvious reasons and turned a piece of stock up to the new dia and over long.Ground a single point tool to the rack profile and proceeded to cut the teeth.Easy peasy started with half millimetre cuts and finished at quarter mm.No problems lovely finish.Full depth 2.8mm
Then raised the cutter 1 pitch and took a single pass on each tooth.Then lowered the cutter 8mm 2 pitches and cut again to give the involute form
Looks good and seems to work on the rack,but now have to finish the pinion
and mount to check centres and working etc Another day,but very happyView attachment 94705


View attachment 94706


View attachment 94707


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## bazmak (May 11, 2017)

Finished the pinion and press fit a 35t mod 1 changegear.Made and fitted
a pivot pin to a 6mm hole in the apron just as a trial fit.Had to pack the
apron 20 thou and run a needle file over the pinion teeth.Knowing I was out by 20 thou in the centres I drilled a new 8mm hole over x 30 thou with an end mill
then made a new pivot pin.Runs well at this stage.Then bored and bushed the apron for the handle/drive gear.A nom 60t spare mod 1 change gear.Next to make a 3/4 arn handle and shaft before setting everything up to run smoothly


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## bazmak (May 12, 2017)

I first turned the drive shaft and fitted the 60t gear,light press fit and key
Made the central boss from a piece of 50 dia mild steel.A short piece of 
knurled bar from test piece of knurling thread.3 arms from 8mm stainless steel
and 3 no ball ends.All went together well and works a treat.Now to start turning my thoughts to the 6 station turret,while I tidy this up and bed in 
all the slideways etc.Must admit it looks good and feels good
Here are my thoughts please comment or make suggestions
6 way turret round or hexagon ?
had in mind to fit a dovetail slide to the top plate in line with the lathe axis to give more movement/adjustment
and to help take up some of the height.Lathe centre height is 91mm
used 20mm for the top plate.I plan to make the turret 50mm high with a 10mm
plate under to fix the ratchet/stop for the station
So that gives me 91 c/ height - tp =71mm - 25mm turret =46mm for combined
dovetail slide and turret bottom plate.Also have in mind to bore out all the stations and fit top hat collars locked with std gudgeon type pins
Each collar + spares can then be fitted with small drill chucks and collet chucks for drills taps reamers etc Also a die box and maybe a chasing box
Cant really envisage needing it to make large quantities of small items but
who knows maybe brass thumbscrews


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## bazmak (May 13, 2017)

I stripped everything down again,blued and scraped the top plate,finished a few details,set and greased and off we go ready to build the turret assembly
Few tight spots,down to the lathe ways.Need to get a couple of thou of the underside of the ways at the headstock end.Also later I will make a new piniom
pin with both diameters offset by 1mm eccentric then I have adjustment to 
take out some backlash from the rack/pinion.Ready for phase 2.Short video to show motion   https://youtube.be/Xtncwb2bfpw


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## bazmak (May 13, 2017)

Again I got the link for utube video but it doesn't seem to work DOH
Look on utube search capstan turret attachment for mini lathe


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## Blogwitch (May 13, 2017)

Looking really good Baz.

Here is your Youtube fix

[ame]https://www.youtube.com/watch?v=Xtncwb2bfpw[/ame]


John


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## ShopShoe (May 13, 2017)

bazmak,

Some thoughts I have (You did ask.) Maybe too much, but what the ...

I like the idea of collets to hold tooling. ER series?

Each "station" mounting some type of quick-change? that can be indexed in some way so that orientation does not have to be reestablished on changing tools.

Some type of one-step advance from one station to the next, either mechanically or with a stepper motor?

A station on the turret for drilling done somehow: If you went back and added an indexing feature to the chuck/headstock, you would have a great way to make bolt-hole circles (I.E.: a flange or nozzle) on a turned part while still in the chuck.

I admit to wanting to see you build the mouse that turns into an elephant, but I find this project just as interesting as an engine build. 

--ShopShoe


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## bazmak (May 13, 2017)

Thank you shopshoe,what I have in mind is this.Simple ,not too complicated
after all all it only a mini lathe no 2, so its only for playing about with.
I propose to make a cross slide at 90o to the table in line with the axis of the lathe Nom 100 x 20 flat same as the table top,lockable with nom 50 mill adjustment to take up differences in tooling length and reduce centre height
to nom 50mm. 2no 100mm discs would then be mounted, 20mm and 60mm thk.
The lower one fixed to the compound slide and to house the ratchet for locating the turret stations.The 60mm one will be the turret to spin and locate each station with a spring loaded pin similar to the 4 way lathe tool post
but more accurate and robust
When that is done and each station confirmed and locked and everything in situ I  can then centre drill each station from the headstock to give a location for milling the flats and boring the turret.Each station to be bored say 40mm dia to hold top hat tool 
holders.These will be clamped with gudgeon type pins as typical capstan lathe
and can be bored/threaded to accept chucks/collets and special tooling
I will make a couple of ER32 and ER16 collet chucks to suit my collet sets
Already looking for small compact keyed Jacob style chucks etc etc
Thank you for your comments,most welcome any more greatly appreciated
Like most things this is evolvlng as I go along


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## ShopShoe (May 16, 2017)

Bazmak,

That sounds doable. Thank you for the explanation. I was having trouble visualizing the orientation of the top-hats and how that would work.

Good luck and waiting to see what you do next on this project.

--ShopShoe


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## bazmak (May 17, 2017)

Well I hacksawed another piece of 100x20 flat steel x 150lg.Cleaned up in the mill and cut a 50 wide x 11mm deep female dovetail.Made a male dovetail
and a brass gib.Fitted and assembled.Works well.Onlu fly in the ointment
I broke an M5 tap and don't think it will come out.Its not doing much so
will probably dummy the hole with a caphead .Just had 2 slices of 100mm dia cut ready for the turret.Paid $12 cutting charge but better than a hacksaw
Starting to look good


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## bazmak (May 18, 2017)

Made the turret base from a 25mm slice of 100mm dia mild steel
Made and fitted a 12mm dia shaft and turned a 55mm dia location spigot
the same as the std main spindle housing on the std 7" lathe
My rotary table has this size spigot and if need be I can mount to it
Lined the vertical turret shaft with the lathe headstock as shown
and am now turning the 60mm slice to make the actual turret


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## bazmak (May 20, 2017)

Basic premise is to make the blank turret and complete the locating/locking mechanism to ensure I get repeatable accurate location for the 6 stations
I made a more roust version of the mini lathe 4 way toolpost system then set up so I can pass the turret between lathe and mill for multiple operations with 
confidence that any maching will be accurate to the 6 locations.Heres what I have done so far.The blank turret is not to size yet,it does not look right but too high.The flats need more machining and the locking 

handle is temporary


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## bazmak (May 21, 2017)

I planned to make 6 locking pins from 12mm dia bar,one for each station
inserted from the bottom with a nut to pull up from the top.However I 
realized the pins would clash with my locating ratchet on the u,side so 
had to mount from the top with a nut clamping down.I also made only 3
each one clamping 2 stations.These will be locked/clamped tight while
I machine the 6 housings.
The housings will be nom 22 to 25 mm dia and can be machined in either
the lathe or the mill.I envisage centre drill and small step drill in the lathe
for accurate alignment the transfer to mill for more oomph.Final size will be 
the boring head.Mine has an R8 spindle for the mill but would prefer  to 
finish in the lathe with light cuts.For that I will have to adapt to MT3
Will see how it pans out when I get there


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## bazmak (May 22, 2017)

Well I pondered long and hard on the best way to machine the 6 stations
Fortunately I had the foresight to setup for both lathe and mill,thank goodness I did.The lathe was underpowered for the larger diameters and the rack feed
was too coarse.So I centre drilled and then stepped drilled to 12mm dia
which was the most accurate way for alignment to the headstock and station
locations.I then transferred to the mill to use 16,20 and 22mm endmills to 
25mm deep and flat bottomed.Then set up mu boring head for its first
major use .Working well so far.Will make a couple of top hat tool holders
to use as a plug gauge to check  the bores for size


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## bazmak (May 24, 2017)

Turret stations bored out to 25mm.Made and fitted 2 no blank tool holders
Need to finish off the clamping gudgeon pins and then plan to make 2 no
ER 16 collet chucks,a die holder and a tapping chuck.May also drop back 
to my second lathe thread,as the new handwheels and tailstock chuck have arrived.Hopefully the capstan will come straight off and the original  carriage
and tailstock can just slide back on.Should only need to remove the leadscrew brkt and refit. Just 2 screws


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## bazmak (May 26, 2017)

Tidied a few details up,made and fitted a locking handle and incorporated
another smaller pawl/ratchet to top of the turret and u/side of handle
Now when turret is locked the first 30o of the handle unlocks the turret
and a further 60o swings it round to the next station,and then back to lock
Works well,will show some video when I have made a few tool holders
and set them up with chucks etc.It will look prettier


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## Wizard69 (May 26, 2017)

Bazmark;

Looking really nice.   Waiting on the video.  

Im wondering about cross slide travel, it doesn't look like you have a lot there but that could be the pictures.


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## bazmak (May 26, 2017)

Hi Wizard,there is no cross slide at 90o as such.The carriage and turret
stay fixed on lathe centreline. The dovetail cross slide is parallel with
the lathe axis and has a travel of nom 70mm.I made it for 2 reasons
To take up some of the height from bed to lathe centreline and to give me
some adjustment on tool extension.For instance if I have a MT2 centre
that projects say 50mm from the turret,but a Jacobs chuck with a long drill
projects say 120mm it will help with settings.(I hope but its all in my head)
until I fill the stations and start using it.As I said at the beginning its all
in my head and on the back of a cigarette packet
One thought that entered is that the compound slide will get in the way
so I have in mind to make a T slotted table to fit to the cross slide then
make front and rear toolposts for holding turning/parting off tools
It will all come out in the wash. Regards barry


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## goldstar31 (May 27, 2017)

Barry
          Obviously, I cannot comment on the turret as 'mine' has yet  to be tried let alone fitted!

However, I did the  sub table  thing some time back. I bought a 918 lathe or actually a 9180 which was one which would accept Myford chucks etc! The tee slots were 'the wrong way round to accept my collection of Myford tooling and I simply added a 28mm thick subtable without the slots and simply tapped it to receive such things as the George Thomas inverted rear parting tool, the vertical slide and the various rotary tables and dividing heads  formerly on the previous lathe.

Really there was nothing revolutionary in it as Cleeve had fabricated a tee slot arrangement to use his lathe for milling. That was in Engineering in Miniature and the kit was sold by Blackgates Engineering.  Chaddock of Quorn fame had two 'blocks', one of which was a bit orthodox whilst the other was simply peppered with holes and bolted or tapped ad nauseum. The latter was simply chucked away when filled with too many holes.

So others might find the foregoing sort of useful

Kind regards

Norm


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## bazmak (May 27, 2017)

Norm,i know its nothing new.My sc4 lathe has a T slotted cross slide and great for moving the whole compound in and out.When the capstan is finished
with multi options for tooling I also need some tooling options for turning
and parting off etc.The best way will be to remove the compound (2 screws)
and make a sub table and front/rear tool post for turning etc.A bigger T slot 
table seems to be the answer.2 options would be to make a new topslide  or
a table to simply bolt on to the existing cross slide.Dont want to lose too much height,but having had a quick look I don't think I would be turning large diameters on this lathe with the capstan fitted.So will probably go for a bolt on table with shallow t slots to hold a front and rear tool post.Will probably go for
cast iron as its easier for machining the T slots.Maybe about 16 thick.This will allow turning nom 85mm dia max.I am also going to make a new leadscrew brkt at the tailstock end,then the entire capstan assy will just wind off without
having to take the brkt off.Lathe can then be used as std with compound and 
tailstock Or the capstan assy wound on with tailstock removed and the table replacing the compound.Sounds easy and straightforward. I wish


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## goldstar31 (May 27, 2017)

Barry
         I can see your logic!  I confess to loving my rear tool post which has sort of been with me a long time- with great results.
When I changed from the Myford with its bull wheel which served as a dividing head( laugh!),  I sort of was obliged to find another means of dividing- in the lathe. Hence the Hemingway rotary table and the Thomas Versatile Dividing Head had to have something to -- well, hang onto!


Digressing further( perhaps others will use it), I did a crafty interchangeability so that I could move things onto the mill or the lathe olr the Clarkson tool and cutter grinder and digressing even further, could get the Potts spindles in use or even swop the spindles and tooling from the Quorn, the Clarkson, the Kennet and my funny little fabricated Stent.

Perhaps someone will arrive in white coats and a strait jacket- but that is what I did.

Meanwhile- back at the ranch as our cousins would say, I got a daft little ML10 with a 65 tooth bull wheel which is not a fat lot of use as a dividing head but some earlier character had drilled a Burnerd Chuck with holes around the periphery.

Lateral thinking???

Regards

N


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## bazmak (May 30, 2017)

Made 6 toolholders .Just finished screwcutting the 2 no ER16 collet chucks
Next is to cut the internal tapers.Also to cut the 2 no MT2 internal tapers
Awaiting for arrival from china of 2 no cheap 10mm Jacob type keyed chucks
which will be fitted to the other 2 stations then we are good to go.  Video time


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## bazmak (May 31, 2017)

Finish the 2 no ER16 collet chucks and the 2 no MT2 holders with 2 blanks 
ready to fit 2 Jacobs chucks.Its starting to look quite professional
Its now easy to slip off the tailstock and slip on the tarret assy,no screws
Its also obvious that for use the compound needs to come off (2 screws)
and a T slot sub table to go on.Say 2 screws and next job.The best option
I feel is to mount the QCTP to the front and make a rear parting off tool post
A quick thought and then get some material.I have a piece of 100x20 ms flat
that would do,but am not confident my only,cheap chinese T slot cutter would be up to it so will buy a piece of cast iron nom 75x20 flat x 160 lg.A platform to the front to mount the qctp at the correct height and sq or round tool post
at the back for parting off.This should limit the interference to the turret and
can do multiple turning ops from the front with parting off the usually last op


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## gunna (May 31, 2017)

I hadn't noticed before but in all your photos, South Aus seems to be one day ahead of the rest of the country.

Ian.


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## goldstar31 (May 31, 2017)

Greetings Barry! I'm having serious doubts about the possibility of cutting tee slots even in cast iron.
I'm not writing about heavy duty milling machines or such but on - in my case a, a reasonably powered mill drill. I was cutting the tee slots for a Stent in cast iron and the home made Myford tee slot cutter -------snapped. It's neck broke.
To be fair, a Stent 'top' is a series of runs all of 10" and I hadn't power feed then. Today, I would guess that with a power feed now that I would 'get away' with it.

Again, on the same job, I was cutting the long 10" vees- and knocked some teeth off my hss cutter.

It suggests that a power feed is desirable or a re-think and either fabricate or simply drill and tap holding down things!

Meantime, it's excellent reading for which I thank you

Norm


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## hanermo3 (May 31, 2017)

Fantastic thread and great work !


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## bazmak (Jun 1, 2017)

Hi Norm,my thoughts exactly,great minds think alike. I fabricated a t Slot
table for my woodwork lathe mod and then reworked it to make an angle plate for the mill.I also fabricated a T slot faceplt for my first mini lathe and now 
use it for my rotary table.They work great and I use them all the time BUT
I wanted something that looked a little more professional so have decided to
make one from solid.Not sure of the cutters capabilities so one option is to order a lump of cast iron.
I had bought a 1m offcut of 100x20 hrms and used most of it,when I checked
I had a piece left 170mm lg.Devine intervention I thought so will give it a go
If I knacker the cutter then all I have lost is $20 or so.Whats the point of keeping a brand new tool in the drawer because your unsure it will do the job
So I have made a start,Will try and rough out where I can with carbide then give it a go.Dont know if its HSS or Hcs but when I used a similar cutter the speed was too fast and it quickly took of the edge,so this time will take it slower with some cutting fluid.2 no dovetails approx. 7" long. Fingers crossed


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## goldstar31 (Jun 1, 2017)

Hi Barry
Thanks for the comments but I'm not in your league.

I'm hoping that your saga will create a spark or two with newer modellers.

One daft thought is that the top of the rotary table  idea would go down well on a lathe plate.  It might solve holding problems for lots of things.

Meanwhile, I await the next exiting instalment.

Regards

Norm


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## bazmak (Jun 2, 2017)

Well afer all that worry and procrastination it was a piece of cake
The cutter did a good job and still kept its edge,but it was a long haul
The first slot took me about an hour but the second less than half that
The big problem was clearing the chips.They built up quickly fore and aft,cutting fluid made it worse changing the fine chips to one big clump
which quickly bound the tool and bogged down the mill.After a lot of the trial and error I found the best way was a very slow hand feed for about 5mm
then wind the cutter all the way out,and clean away all the chips.Add a little cutting oil and repeat.About 36 times per slot.Very happy with the result so far
next will be to finish it off and make a front and rear tool post


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## bazmak (Jun 4, 2017)

The next part of the sub table was posted in the second lathe thread
so anyone following will have to flip between the two
Sorry but the  2 threads have converged,its difficult to say which is which


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## bazmak (Jun 5, 2017)

All major parts have been made and fitted.Only tweaking etc to do
will take time with not a lot to show but will keep this thread going
I will post the video link from Utube below but have not had much success
lately.If you only get the link the will you please amend it as someone did
on the last couple of videos.Thanks barry     https://youtu.be/4pfi53HNRY4


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## Cogsy (Jun 5, 2017)

Here ya go Baz:
[ame]https://www.youtube.com/watch?v=4pfi53HNRY4&feature=youtu.be[/ame]


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## bazmak (Jun 13, 2017)

Well 2 no cheap 10mm Jacob chucks arrived from China,so fitted  to 2 blank stations.Made a no of pointy type centres and fitted to chucks and collets to check station alignment.Alas poor Yoric theres me thinking like an engineer
that after all the effort and setups that the turrets would all be in perfect alignment.2 were correct,2 were + 50 thou and 2 were -50 thou.So I had to spend a few hrs aligning. Made a new male location pin from silver steel about
10 thou bigger and proceeded to to nudge with a file until 4 were correct
The other 2 were about 1mm out so milled about 10 thou off the 2 
correct female location faces. Alls well that ends well.All were within a few thou under a loupe which is near enough for now.Will now switch to the 2nd lathe thread to make a die box and tapping head. I HOPE


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## bazmak (Apr 1, 2018)

A chap called Mike from Tewksbury emailed me with questions about the capstan,so hopefully he will log on and become a part of this forum.In order to help him if he does i will ressurect this thread and replace the deleted photos


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## goldstar31 (Apr 2, 2018)

Barry,

          I have no idea whether this is constructive but as you have a Myford ML7, some time ago a Ken Metcalf described making a capstan attachment for his ML7.  I guess that it was in Model Engineer.

Clearly, I have little interest because I bought a possible capstan attachment which -- has a flat base.

The rest is one of those 'round to its'

Cheers

N


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