# Making a cup in the end of a bar



## Round in circles (Jan 29, 2015)

I have a need to make a shape like an cup or drinking tumbler on the end of a 1 & 1/2 " bar of steel and once made and tested for correctness I'll turn a stem on the bar so it resembles a stemmed wine glass so I can fit the cup in a drill press and cut out zillions of foam circles . The cup's internal dia is 22 mm , OD is 24.5 mm with a depth 11 mm .

 I've turned the basic shapes but found it very , " chattery "   inside the cup and the finish inside  looks like fish scales rubbed up the wrong way. On cutting out a disc the roughness makes it a bit too tight to remove the disc unless I stop the drill and use a needle to pick it out . If it were really smooth I think it will fall out as I raise the  cutter 
  The tool I'm using is an overley long 3 " of ground round 1/2" square bar 1/4 " thick at the round part of the bar ,  it has a 1/8 th " purpose ground beak that is the cutting part . The boring bar appears to have been hand ground up from an angled left hand high carbon steel cutting tool 

 I've been using speeds of 500 for the external roughing out & 1270 to give a finish , 500 & 805 for the internal steel removal .

 I've tried kissing it on the grind stone to get the cutting edge and angles in a reasonable state.

 My questions are these ....

(1) 
With the tool post on the right ...work  on the left , bar boring the cup out towards the front/saddle of the lathe , I'm working blind ..I can't see the tool tip . Do I invert the tool put it on the back of the tool post at the center height and cut at the back edge /away from the front of the saddle  . ( I have a crippling spinal injury that stops me leaning forward to see the tool tip inside the cup ).

(2)
On the tiny beak cutting tip , the actual cutting tip is almost good enough a point to run /turn a fine internal thread . Would my putting a 1/32 flat /slightly radius'd chisel point on the tip  make a better less noisy cutter so I can use a few more thou to try and get a better internal finish ?

I feel that once I've ground the " beak ", the boring bar is only going to be fit for scrap quality high carbon hand forged steel as there will not be much of the beak left .


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## Jim2 (Jan 29, 2015)

Yeah, you can cut on the far wall up-side down--no problem as long as you can reach.  With 22mm ID that would be no problem.  Otherwise a mirror can be used as well.  Oftentimes, no real good way of seeing in a bore like that w/ tool-post in the way and all.

If you're having trouble with finish, I'd suspect lack of proper clearance on your tool-bit. . . .  If the bit is rubbing instead of cutting you're going to have lots of chatter.

My lathe is nowhere near capable of cutting at the speeds that you're at, but that does sound awfully fast unless maybe using carbide?  When boring you want to limit your tip radius as boring bars tend to be flexible--though 11mm isn't much depth either.  Make sure you're choked up as much as possible to make the most of your set-up.

HTH,

Jim


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## jererp (Jan 29, 2015)

I'd make sure the cutting edge is slightly above center. Part geometry gives you more tool clearance. Also, if possible shorten the boring bar overhang. Turning at a slower RPM may reduce the harmonics of the boring bar.


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## Boswell (Jan 29, 2015)

jererp said:


> I'd make sure the cutting edge is slightly above center. Part geometry gives you more tool clearance. Also, if possible shorten the boring bar overhang. Turning at a slower RPM may reduce the harmonics of the boring bar.



while it is not quite your question. If you put a spring inside the "cup"  it will compress when you cut the foam and eject the foam when you back away from the foam.


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## Hawkeye (Jan 29, 2015)

Alternatively, you could drill an angled hole or two out through the cup so that a wire or screwdriver can be pushed in and pop the cutting out.


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## samthedog (Jan 30, 2015)

I would just use a small grinder to grind the cup smooth like a toolpost grinder and add a spring as Boswell mentioned. No matter how smooth you make the punch, if the foam is compressable self ejection will not occur. I have seen many presses and punches used in shoe factories that all had to be cleared by hand or a spring.

Paul.


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## Dave Smith (Jan 30, 2015)

drill a hole in the backside and just give a short blast of air to remove it without damage-----Dave


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## Round in circles (Jan 30, 2015)

Thanks for your input guys , I read up about the harmonics earlier today and so used a much slower speed as well as putting the boring bar in upside down  to cut on the farthest wall after a gentle regrind , had to pack out the tool post seat to raise it enough to get the cutting edge at centre height as I don't have a nice and handy quick release tool post that I can compensate things with YET!  There is sufficient clearance to cut right through the 10 mm thick  foam as the recess is 13 mm deep .

 The spring ... Having cut about 100 of the foam washers tonight  , the  OD is almost exactly 40 mm and ideal for my needs I was trying to think of a way to self eject .  I don't possess a compressor ,so every washer was cut to almost the half way point on both sides and then hand removed from the sheet of foam every time I'd semi cut 12 holes ...T'was a long laborious task especially in the near frost conditions out in the garage. 

 In the centre of the cutter I have set a pointed bar to guide the foam under the cutter through the same hole so everything lines up for cutting from both sides.

Now with the spring ejector and a sort of face plate idea I may have it cracked ...what I don't want to do is tear the faces of the foam disks up with the spring as the cup rotates in the drill press.
 I did try to simply use the drill press as a stamper/press  to cut through the 10 mm thick foam but it will not do it .

Just had a cup of drinking chocolate ,  as I made it I had an inspiration .:talktogod::roflmao:.

 I'll make the cup 2 mm deeper , open up some of the solid body and insert a captive spring operates shuttle with a nice big face to press on the foam and also reposition the guide pin by making it a lot longer and locked in .... almost up in the drill shank of the cutter or maybe use a much thinner bar and actually set it in the 1/2 drill neck 
 as in this ...




I'll have a play at it tomorrow , once I've put an electric fan heater in the garage  as we're forecast snow & a sharp frost  tonight .


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## Dave Smith (Jan 31, 2015)

you should have an air compressor to make it quick and easy--I think you are over making a simple punch that should work fast in just one side stroke  full cut------working with a plunger and spring is going to make it harder to compress it all while forcing the punch down----I just cut a side slot little over half way through the punch so the punched item can be taken out the side when the second piece pushes it up---I made mine for leather and rubber holes and they work great----I just cut a gas filter in half for two cheap cutters-------Dave


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## Round in circles (Jan 31, 2015)

Dave Smith , do you have to stop the drill press to extract the cutout and or blow it out ?

I considered one of the old hoop and stem type saddle makers leather punches that self eject if you fill the cutter void up by continualy punching things out .  I saw a 40 mm one on eBay yesterday morning ..I'm not bidding for it .....when I looked the price was already at £ 49   ( $ 75 USD approx.) aand still four or so days to run 

Sadly I dare not have a compressor yet unless I can find a super quiet running  one that does not make a hissing sound when using an air blast .  For  it would give the Witch & Goat   next door yet another thing to ***** and whine at alongside me being disabled , no longer fit to work sensibly & getting a government funded Motability car to help get me around .  

Her husband " Has to work his fingers to the bone all week & I stay at home living the life of Riley  " according to one of her outbursts directed at me and my family . 
He works for the government in the driver licensing place here in Swansea and wouldn't know a decent day's work even if it bit him twice in his butt & smacked him between his eyes with a baseball bat , neither would she.  :roflmao:

An  Eureeka moment ???
I've just had a thunk , if I turn up a cutter like yours but make it a bit longer in the body and in the elongated  cut out insert & fix a round bar cut to a wedge to give an automatic ejection slope to eject through the cut slot it may work .  I'd like to make about 24 x 14 x 14 of these foam washer inserts  ( the amount of material I have)


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## Dave Smith (Jan 31, 2015)

David---if the size doesn't have to be super exact sized--then just look for a thin walled tube or a  piece of conduit like 1" electrical conduit and cut out a large side opening and the pieces should come out real easy---make it long enough and try it out--you are only cutting foam so the side cutout can be large without strength being a factor---I would make it approx 6 inches long and a long side cutout----just use a file or emery paper to sharpen the tube on the outside edge--leave the ID alone unless you just want to buff it smooth--hope this helps---Dave


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## Round in circles (Jan 31, 2015)

I didn't make it to the garage this afternoon as my  disability flared up .

The foam I'm cutting into disks is 10 or so mm thick, of a similar density to the rubber foam  , rubber thong between the toes " Flip Flop's" we used to wear down on the beach in the 1960's & 70's. (now we use " Croc's "  which is also a similar density foam ).

 It does indeed compress during cutting and expand to grip inside of the cutter once if is cut free of the sheet . Picking it out of the stopped drill press is fairly easy but not wanted as I take about 3 min to cut every 14 disks . 

Plus , will my 30 odd year old drill press take another 4500 or so stop's and start's ? :lmao:

 Yes size does matter :roflmao:

I'll get some pictures together and put them up with an explanation so you can see what the project is .


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## Round in circles (Jan 31, 2015)

I'm doubly disabled , as I've got older I cannot do as much nor am I as able to move & lift many things . To keep on gardening for food , pleasure & gentle exercise I designed a plant pot system that will see me turn my toes up and still be going strong. The idea was to use minimum effort and as little material compost etc. as I could get a way with .

The first phase was plant pots made from spare 3 " square rainwater down pipes,  cut in four inches in lengths and plugged with a 3/4 " thick open cell rigid foam plug 




This worked well, for I can stand the compost filled seed growing pots in trays without them tipping over,so allowing me to carry a tray in my right hand whilst using my left crutch to get about .

 A few years ago things went even more pear shaped , I found I could not carry the tray's when full . Moving around was becoming even more difficult so using smaller trays was not really an option for it would mean double the journey's from my second man cupboard ( A quality dwellable wooden log cabin ) to the glasshouse or around garden .

 I came up with the idea of using smaller tubes but this time use round tubes so in the end things would be even lighter .
   Initially I used square chunks of the open cell rigid foam for the plug but found that there was a tendency for the foam to die or the roots to grow deep into it . Tearing the roots free of the foam usually knocked the plants back by a couple of weeks or so .

 I experimented with some ( rigid closed cell foam ) unwanted caravan floor awning  inter locking panels .  It worked well, no root problems and no degradation of the foam . However cutting the foam in squares gave a pathway for the roots and was also not very satisfactory as it often popped out as well as being a bugger to insert correctly.






I can get 33 seed tubes in each standard seed tray against  ten of the square pots ( I will still use the square pots for things like bean & curbit plants ).





This is a part cut up sheet of the interlocking awning flooring 






 I made my cutting tool and got a perfect fit in the tubes,  not too easy nor to hard to insert , especially if I pushed the tube down over the insert when it is laid on a table top .. I have 350 of these  tube pots ( made from fire damaged kitchen sink waste water pipes from off the local Freecycle scheme )  with another 400 or more  planned ( I might have to buy this though ).





 A cut out disk showing a central line up /drain hole in the middle




 This blurry picture shows the disk inserted in the end of a 40 mm ID tube that is 75 mm tall .






 The beauty of this set up is that the trays are now about 2/3 less in weight than the  trays with square tubes . The plants don't suffer any  retarding in their growth for I use a plunger peg set in a small board to push the now core of compost and plant roots up out the tube without disturbing the root ball . 
 Now that I cannot bend over much or kneel easily or get back up I have to do most things standing up as straight up as I can whilst using the left a crutch for support . 
To this end I have a 50 mm ID tube that can be taped to my left crutch so that I slide the smaller plant & root ball plug down into a prepare hole in the ground level beds. 
  This now means that I can now consider having lots of tender annual plants/bulbs in the ground level beds as I can now  easily plant them as individual plants .


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## Jim2 (Feb 1, 2015)

That looks pretty ingenious!  I also makes sense that you'd be looking for a way to remove the foam automatically.  I'd hate to be starting and stopping a motor each time for all those pieces.  Hard to say which would give out first--the machine or you!

I was wondering if you could revise your cutter to have an inner plunger that is activated by an outer ring.   The inner portion (plunger) would be connected to the outer ring by means of a couple of pins that pass through the main body of the cutter via a couple of slots.  Here's a sketch





This is just a idea, and I know it's not fully fleshed out.  There's still the matter of pushing down on the ring to activate the plunger while the cutter is in motion. . . .  I hadn't really figured that part out.  Still maybe something to get you started?

Jim


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## Round in circles (Feb 1, 2015)

I just love your drawing Jim ,

I've not moved far enough from the Stoneage & my cave  to be able to comprehend or do  such marvelous CAD stuff .


I can see that an external spring pushing down in an inner plunger and an external  collar above it to retain it would solve things fairly easily and also be adjustable to easily taken apart to put a different spring in place should the need arise.

 OK next challenge  .....the plunger and cutter body it would need  slots cutting in them for movement over  locating pins  .
 I have no mill , nor anything such as a milling  attachment for the lathe .   

Perhaps , I may be able to disk grind a ( killed by me :shush: ) dead centre  to make a crotch pad for the lathe , I also I  have a 2 " wide home made sort of half reasonable  " Vee " block .... so use either of them to accurately drill a set of clean chain drilled holes through the middle of a bar .

 So , perhaps I can chain drill in a section of the extraction piston stem ( may be very fiddly ) to make a movement slot and then use a real cheap ancient 24v modeling grinder i have with small stones , disks and rasps etc etc to see if I can take out the webs between the chain drilled holes , then slip in a very thin warding file to clean up the slots for a locating pin to slide through easily . 

I had envisaged the extraction device to be internal above the extraction piston and a necked /shouldered cut out ( it would be the equivalent of the slot idea ) for movement with the extractor spring internal in the body & above the head of the extraction piston stem. 

 Seeing as it starting to snow , is freezing hard and will evidently be real " Brass monkey"  weather tomorrow , I'll have a while to sleep /hibernate on things .


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## Jim2 (Feb 1, 2015)

That's a SketchUp drawing.  If you're not familiar, it's a free program from Google.  I started using it 2 years ago.  I'd never done anything in 3D before, and really had no CAD experience.  There's lots of tutorials available online.  I watched a few and started playing around with my own designs.  Give it a try--too cold to work outside anyway, right?

Drills, grinders, and files--they'll do the same job as the mill.  Will just take a little longer, but it's not really a terribly huge project.  Persistence will win the day!

Jim


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## stupoty (Feb 1, 2015)

Round in circles said:


> Her husband " Has to work his fingers to the bone all week & I stay at home living the life of Riley  " according to one of her outbursts directed at me and my family .



Now that is what asbo's were created for 

did i ever mention the time my neighbours called the noise pollution people about  the arial mast on their house being lose and banging on the wall. Ahhhh ow well takes all sorts to make a human race 

On topic, can the punches be used without turning the drill on if their sharp enough? I occasionally want some high density foam washers etc and i normally hack them out with craft knife or scissors. Your method seems better 

Stuart


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## Dave Smith (Feb 2, 2015)

Round in circles said:


> Dave Smith , do you have to stop the drill press to extract the cutout and or blow it out ?
> 
> 
> An  Eureeka moment ???
> I've just had a thunk , if I turn up a cutter like yours but make it a bit longer in the body and in the elongated  cut out insert & fix a round bar cut to a wedge to give an automatic ejection slope to eject through the cut slot it may work .  I'd like to make about 24 x 14 x 14 of these foam washer inserts  ( the amount of material I have)



use your moment thinking--- and before you cut the long slot out--use some fine emery cloth to finely polish the inside of the tube and only have the cutting section no more than half inch and the slotted about 2 or 3 inches---make sure the slotted out area is deeper than half the diameter---so the punch outs will spin out as you are cutting more------you won't get a hole in the center but you can use a little lubricant on the Id every so often to help them slide up and out easy---this will keep your press running without stopping for each piece---you can always solder a small angled piece on the inside to make sure they are forced out if necessary but if your slot is wide enough then they should eject with the spinning force---if your tube has a thicker wall--- then when you turn the id on the lathe turn the area just after the cutting edge a larger Id-----then cut out your long slot---they definitely will spin out easy then-------Dave


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## Reeltor (Feb 2, 2015)

Round in Circles,

This is a little off topic from your question.  

Last year I planted a vegetable garden, it was the first one I've done at this house and I've been here almost 18 years.  This year, I want to germinate plants from seed so that I can try different varieties and also save some money.

When I first saw your PVC planting tubes I thought what a great idea!
I do have a question; why not plant your seeds in paper cups?  You can slit the paper with a razor knife and plant the cup and all.


Mike


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## Round in circles (Feb 3, 2015)

Reeltor said:


> Round in Circles,
> 
> This is a little off topic from your question.
> 
> ...



Mike ,
Plastic , polystyrene & paper drinking cups have small bases & fall over far too easily when I'm doddering around. They also use 2/3 more sowing mix.
Remember I said, "  I can get 33 seed tubes in a seed tray against 12 squares " ...  compared with 11 drinking cups . Last year I grew nearly 1,000 seeds of one kind or another into viable plants .. 
I want to do more in the future . This is the reason I want to make my blue disks and make more tube pots . I've been gardening man and boy for 60 years .
I now run my gardening with the, "  All New Square Foot Gardening" scheme  designed and written about by an American  guy called Mel Bartholomew having individual plants is small handy containers is ideal for me and my disabilities. 

I have an 8 x 12 foot x 7 foot tall glass house with water and power for a fixed thermostatically & water misting controlled hot misting propagating bed , there is also 28 adjustable micro misting spray heads on the inside perimeter . I don't have the normal sort of fixed staging you'd expect in a glasshouse .  I instead I have five stainless steel castor'd catering trolleys 2.5 x 3.5 foot at the platform, two shelves on each trolley .  These make fantastic seed/ plant starting platforms due to light reflection etc. As soon as I'm able the trolleys are pushed around my raised beds , trays of germinated seeds / plants are deposited wherever I can find a place for them till they are big enough for planting out /transplanting  and the next set of seed tubes are started off on the now emptied trolley .


 I'm not allowed to play with sharp things .... a 1/2 wax crayon is about the smallest thing I'm allowed to draw /write with ..so long as the governor & wardens know I've got it .  
Seriously ........ I'm on a high dose of Warfarin ( anticoagulant , also a  rat poison ) ,  getting any deepish cuts will see me bleed like a pig & have to go in a blues and twos to hospital 15 miles away to get the bleeding stopped , so I've promised my lass I won't play with sharp knives etc if at all possible to give her a bit of peace of mind .


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## Round in circles (Feb 3, 2015)

Dave Smith said:


> use your moment thinking--- and before you cut the long slot out--use some fine emery cloth to finely polish the inside of the tube and only have the cutting section no more than half inch and the slotted about 2 or 3 inches---make sure the slotted out area is deeper than half the diameter---so the punch outs will spin out as you are cutting more------you won't get a hole in the center but you can use a little lubricant on the Id every so often to help them slide up and out easy---this will keep your press running without stopping for each piece---you can always solder a small angled piece on the inside to make sure they are forced out if necessary but if your slot is wide enough then they should eject with the spinning force---if your tube has a thicker wall--- then when you turn the id on the lathe turn the area just after the cutting edge a larger Id-----then cut out your long slot---they definitely will spin out easy then-------Dave



Yes ....gotcha  ... " Brilliant " :thumbzup3:, 
 Now my only problem is .......where do I find a 40 mm ID bore thin wall smooth tube six inches or so long , that's why I turned the thin wall on the cutter .  
I thought I'd cracked it with some new car exhaust piping but the diameters are ( so far ) way too big on the bits I've been able to source .
I may have to end up inserting a turned up cutter head  inside a bigger tube and slipping some /drive /locating pegs in the circumference then glueing a turned cover /collar / sleeve over the  drive /locating pegs to keep it burr free and safe where the pegs have been inserted .  Then make the cut out slot in the bigger tube .  Finally fit a turned insert with the driving flange & spindle to fit in the drill press at the other end of the tube. 

:talktogod: I have an inkling that contractors construction 12 or 20 foot long scaffold tubes may be my salvation , along with judicious use of my 9 " long indexed boring bar & electric " Whizzer "  cutter ......  Just got to beg , steal or borrow a short length that I can get in my car .:lmao:


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## Round in circles (Feb 3, 2015)

stupoty said:


> Now that is what asbo's were created for
> 
> did i ever mention the time my neighbours called the noise pollution people about  the arial mast on their house being lose and banging on the wall. Ahhhh ow well takes all sorts to make a human race
> 
> ...



Yes look on eBay for " hollow punches " or " saddlers punches " some are as cheap, as chips ,. others are an arm and a leg & some.
You just lay the punch over the foam which bis laid over a decent backing board and give it a wellie with a big hammer , as the throat of the punch fills up with the foam disks  they gently self eject through the slashed throat .

 The big saddlers ones have a stirrup affair over the punch tube ..usually it's a square bar but I suspect that they can easily be turned down to a round one to fit a drill chuck (  unless the whole thing has been induction hardened or case hardened .. which is unlikely in any case ) .


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## Round in circles (Feb 3, 2015)

Jim2 said:


> That's a SketchUp drawing.  If you're not familiar, it's a free program from Google.  I started using it 2 years ago.  I'd never done anything in 3D before, and really had no CAD experience.  There's lots of tutorials available online.  I watched a few and started playing around with my own designs.  Give it a try--too cold to work outside anyway, right?
> 
> Drills, grinders, and files--they'll do the same job as the mill.  Will just take a little longer, but it's not really a terribly huge project.  Persistence will win the day!
> 
> Jim



Thanks for the programe's name Jim :thumbzup3:.. Guess what I'm going to play at till the weather warms up a bit ?


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## Dave Smith (Feb 4, 2015)

Round in circles said:


> I have a need to make a shape like an cup or drinking tumbler on the end of a 1 & 1/2 " bar of steel and once made and tested for correctness I'll turn a stem on the bar so it resembles a stemmed wine glass so I can fit the cup in a drill press and cut out zillions of foam circles . The cup's internal dia is 22 mm , OD is 24.5 mm with a depth 11 mm .
> 
> .



what is the ID of the cutter you need---I thought it was 22 mm--but you are talking about a much larger one now---am I just confused--let me know the exact size ID you need and I will look to see if I have a tube that will work---Dave


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## Round in circles (Feb 4, 2015)

Arrrrrraqgh ! 

I'm heavily dyslexic some days in numbers and words ( stroke & medically induced )   I have a fight an a half every time I use the computer , spell check helps but does not autocorrect the wrong correctly spelt word or a set of incorrect numbers .

 The washer cutter needs to be 1 & 1/4 inches internally to give a 1 & 1/4 inch dia washer . ie a 40 mm dia washer .

Thanks for the offer , however I may have a workable solution . (Besides the shipping /postage to the UK is extortionate these days. ) 

 I think I have solved the problem , I will cut the existing cutter off half an inch above the cutter lip in the thicker metal  and then perhaps weld two round bars on opposite sides  & do the same with the driving shaft end . That will give me an extra half an inch clearance to eject the disks by gentle centrifugal force .

I also think that if I set a square faced point in the wooden anvil  ( a ground to size No 10 wood screw going right through the wood  )  I should be able to pierce the foam as I cut the washer and as it separates from the main body it will rotate inside the cup thus making a decent drain hole 
 The next two washers or so to be cut should see the fully holed washer ejected.


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## Round in circles (Feb 5, 2015)

There is an old  saying that  states " Strong belief triggers the mind to find the way " ,  I have it pyro-iron burnt into a wooden plaque that hangs on the lounge wall not ten feet away from where I'm now sitting.

 Today I went to order my new Mitsubishi Outlander PHEV  , the car is going to be adapted by a specialist company to cover my disabilities .
As I drew up by the company office of those who will be doing the modifications I saw a large car towable,  open  four wheeled trailer loaded with all manner of odd looking bits of what I presumed to be scrap . In it I saw loads of heavy thick walled tubing , so once business was concluded I cheekily asked if I could go diving in the trailer for some bits of 2 inch or so of tube that might be in the trailer , " So I can play on my antique metal working lathe " , " Sure fill your boots " was the reply .  

I'm now the proud owner of several three foot lengths of 43 mm OD  mild steel tube with a 6 mm thick wall , which should be just dandy to make my cutter out of  ).  Even better .. I think it may be cold drawn seamless mild steel for the inside is nigh on as smooth & shiny as a shot gun barrel . 

In a few days I hope to have received a reasonable / decent brand new QCTP , a set of new indexable cutting tools plus a hand full of spare tips and a couple of buckets full of associated lathe working goodies ...
 I think I'll delay doing anything till they have all arrived and then it's going to be " Playtime " folks .

I promise to take photo's and post up how it's worked out . 

Thanks to all those who have commented so far and given me food for thought .


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## Jim2 (Feb 5, 2015)

No telling what you'll find if you pay attention, eh?  It sounds like you've got all the ingredients there or on the way there. . . .  Looking forward to what you come up with!

Jim


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## Round in circles (Feb 7, 2015)

Well folks I finally  got the  Mk 2 version of the disk cutter made and tested , I cannibalized the MK 1 solid turned up bar steel  prototype , took off the cutting lip gave it several shaves and also cut the driving stem down by 1/2 " , then turned up  a separate deeper self ejecting cutter ( it's too long :lmao: so I had difficulties getting it positioned for cutting .  ).  

I had to make an anvil to do the self ejecting but will have to make a new anvil as I've turned the material around the anvil away  too much . This has resulted in the foam tearing away in the last few mm giving a ragged ( still useable ) edge to the disks.

 It looks like I will now be making a complete Mk 3 version cutter & a Mk 2 version for the anvil for I've learnt a few interesting & useful things .

Now some pictures for you to smile at and shrink away in horror from :-

I chucked up & cut down the original disk cutter 

.





 Cut some old scrap metal  tube and turned the disk cutter I /D  to size .
I used a self ground up right hand cutter as I'm waiting for some indexed tools to come next week ... Big surprise when I discovered I'd ground it just about right first time round on a skanky 30 yr old double wheeled general purpose electric grinder .





I chain drilled every 6 mm  using a 4 mm drill after dot punching the drawn in ejection slot . I should have cut the transverse cylindrical slots first to get the edge of my 4" angle grinder disk down in size so when cutting the vertical slots I would not have over run the drilled & marked line a tad .






The ejection slot roughly drilled and ground out.. had a bit of file pushing to do to get it a bit safer across the sharp edges  and aesthetically looking .





 Parts for assembly ..yes it is rough turned , I don't have any precision  measuring devices yet , save for  MK 1 eyeball & some work hardened fingertips ... What do you want ...  Blood ? :lmao:






 The proof of the pudding shot  ... I made 48 disks in just over 7 min .





 The white anvil on the drill press table is located in the centre hole with a turned to size spacer washer with a clearance hole for  the TEK screw . I used some scrap UPVC strip that I've had for 10 years or more for anvil . It has has worked well in holding the foam whilst is being cut out  and also making a centre drain hole in the foam at the same time . You can just make out the fact that the cutter has cut out below the surface of the plastic as it has rotated   , this is how the anvil has been made .

 Give it a week or so & I hope to present a picture of the final cutter version with a modified anvil .


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