Author Topic: ER11 Multi-purpose tool  (Read 11573 times)

Offline arnoldb

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ER11 Multi-purpose tool
« on: November 06, 2013, 06:43:28 PM »
I mentioned in my Corliss build that I need to make a tool to help make nuts and studs.

For all my builds so far, the small quantities of fasteners I needed to make was easy to do on the lathe.  I never made real studs; I just used lengths of all-thread trimmed off.  As to nuts; I've made quite a few M2 nuts by just filing hexes onto round bar by roughly indexing off the collet chuck and counting strokes to get them about the same size.  Needless to say, this is a bit hit-and-miss, and quite a bit of effort.

The Corliss needs quite a few more nuts and studs than any other project I've done, and while standard fasteners, especially nuts, could be used, there are a couple of places on the engine where normal metric nuts are too big for the tapping sizes I'd used.  I could of course just make smaller nus for those spots, but overall things wouldn't look right.  Making all the nuts from scratch is a daunting task.  There's some nice fasteners available online, but I have yet to find one of those suppliers willing to ship to Namibia.

Most of the fasteners in question for this project is M3, so a simple solution would be to take off-the-shelf M3 nuts, reduce the size of the hex and use those.  It's a bit of a compromise, but would save a heck of a lot of work.  The problem with that is that one is never guaranteed as to the starting position of the thread in a nut, and running it up a mandrel to mill down to size would leave the hex shape in all kinds of orientation.

I set my braincell the task of analyzing things.  It came back with the following set of guidelines:
1. A simple "spin indexer" type of device would help make the nuts, but -
2. It needs to be adjustable  to compensate for each different pre-made nut's thread lead-in.
3. Must be quick to change and set successive cuts to mill flats
4. One-handed operation in use without shutting down the machine for each cut; the other hand's needed to crank the mill handles.
5. Quick to set up / remove on the mill.
6. Its for small jobs - so using the ER11 collet set is ideal.
7. Accuracy - good enough is close enough; 0.05mm (2 thou) will do just fine, but its just as easy to get close to 0.02mm.
8. Use whatever bits I have floating around to make the tool

Then the "how about" thoughts started...
How about:
Make the spindle easily removable for use in the lathe, and incorporate a back-stop feature in it for making studs in batches.
Size the "indexing" part of the spindle to take the Myford's change-gears - that leaves a lot of leeway for different indexing steps - or even adding a worm for indexing.  A small indexer could be really handy for model engine making.

A plan was hatched in C-o-C - it's not final yet, but far enough along to start work.

On Sunday afternoon, I made a start on the tool by clocking up a nice clean bit of 16mm silver steel (drill rod) in the Myford's 4-jaw chuck, and turned 14mm and 15mm steps on it, with grooves to act as thread run-out areas:


The next step would be single-point thread cutting.  I know many people don't like this, but it's a lathe job I absolutely love, and can do with a fair amount of success.
Silver steel can be a bit of a pain to get a nice clean cut on.  I've found the secret to be a VERY sharply honed threading tool and a bit of patience.  And of course a good cutting fluid.
Many of you have seen me post screw-cutting antics before, so might want to gloss over all the gory detail to come.  Maybe there's someone who will find the detail useful.

The first step, was to hone up a threading bit on an oilstone.  The threads needed here are M14x0.75 (that's the standard ER11 closer nut thread), and an arbitrarily chosen M15x0.75.  Well not all that arbitrarily; the lathe would be set up for a 0.75mm pitch already, so no need to change the change-gears (yes, I know... I'm a lazy rotter), and as a bonus, the thread would not interfere with the M14x0.75 section at all.
0.75mm is a fairly fine pitch, and needs a fine tip on the tool.  However, the front of the tip does require a slight touch  of blunting, otherwise the tip will snap off the moment one starts a cut, and potentially ruin all the required cutting faces (DAMHIKT).
If you click on the next photo for a larger image, you can just see where I flattened the tip with a light single back-stroke on the oilstone.  The cuts in the paper was from testing the cutting edges.  There's more of them over the piece of paper.  Basically, I'm happy with the cutting edges if they produce clean cuts in paper like the one to top left.  The scraggly one closer to the tool tip is not good enough:

I left things there, as shop time had run out.

On Monday afternoon I brought some "homework" from work; a stuck DDS tape in a backup drive.  I didn't have a chance to hand it in to my company's service department to fix during the day, and they are a bit snowed under anyway.  The cause was obvious and the fix simple:


As I was already had the shop open, and the C-o-C lay tauntingly below the "homework", I shoved the homework in my car for re-installation at the customer the next day, and went back to the shop.
First things first - set up the lathe for cutting a 0.75mm pitch thread.  I got the appropriate change gears out, and gave each a meticulous clean with a toothbrush before installing on the banjo.  To set the gear spacing, I used the customary strip of paper rolled in between:

Of course, while installing the gears, each of the mounting studs got a drop of oil for the gear bushes, and after installing the lot, all the gears got a liberal coating of oil on the teeth as well.
I also gave the lathe's leadscrew a good clean and oiling.  When single-point cutting threads, especially the finer ones like this, it's important that there is no swarf trapped on the leadscrew, and that "everything works like a well oiled machine" - literally.

Next up, set the toolbit to height.  For screw-cutting, its fairly important to get the toolbit dead on center height.  There's all kinds of weird and wonderful technological things to do this, with centering scopes and lasers and so on.  Then there's the trusted, and easy to make height gauge.  I made mine as one of my very first lathe projects, and it's not pretty, but it does a remarkable job. It's simple to use as well; just clean the swarf from the cross slide, plonk it down with the pointer against the toolbit and adjust the toolbit till it's level with the gauge's top - easily judged by rubbing a finger across both:


The toolbit needs to be set at the proper angle.  As my workpiece in the chuck was a bit short for this, I just used a fishtail gauge against a bit of rod chucked up in the tailstock chuck:

Actually, I could have cheated a bit here and not used the fishtail gauge.  When I grind up threading bits, I use the long edges to establish the tip angle from, and can just set it up with a small square in a similar way (or even worse - just line up the the toolbit side by sight along the edge of the cross slide)

I like to double-check things a bit; saves nasty surprises like chucks running into cross slides and so forth.  I did all the checks to make sure there would be adeqate clearances, set the lathe to middle back-gear speed, used a permanent marker to colour in the section to be screw-cut, and fed the tool in to just scratch the marker ink off (you'll see the faint touch-line about mid-way where the thread marking's blurred in the next photo), and got the dial reading on the cross slide for that and jotted it down.  Reversed the tool out, moved the carriage past the end of the workpiece, engaged the threading gears, set the same depth of cut again, and made a pass:


A final check with a thread gauge, and the thread seems spot on:

The blue finger nails raised a couple of eyebrows this week...  That came about from cleaning the spraygun after painting the Corliss parts...  That blue paint stains really well - I even tried acetone to get rid of the colour, but that just made it embed in my fingers.  Note to self, next time, wear gloves!

On to the first cut.  The full cut for this thread needs 0.375mm (just under 15 thou) in-feed.  The Myford is imperial, so I tend to work in thou's when I use it.  The lathe can easily gobble up the full depth of cut in one fell swoop, but this is where the "patience" bit comes in.  I used just over half of the needed in-feed at 8 thou (0.2mm) for the first "real" cut:


Notice how crude the cut looks - which it is.  The silver steel does not like to be machined with a toolbit that's flat at the top (no rake) - even if it's very sharp.  If this workpiece was brass, that cut most likely would have been very smooth, but the silver steel "tears".
I could expound on my own theory about this "problem", but this post is long enough already, so I'll just get back to what works for me, and that is to machine the rest of the thread down in subsequently smaller cuts.

The next cut was was at 10 thou infeed - effectively taking just 2 thou into the thread, followed by a "spring pass" at 10 thou infeed again.  This smoothed out the roughness a lot.  Subsequent cuts were taken in 1 thou increments each till I reached 14 thou total infeed, with a good clean and liberal dash of cutting fluid on the emerging thread before each pass.  This is what it looked like after the 14 thou pass:


The Collet nut doesn't fit yet, as that last fraction of a thou ( eight tenths or 0.0008 thou) still needed to get removed:


The last cut was the most difficult; the Myford does not have a vernier scale on the cross-slide dials, so I worked "between the lines" on the dial, estimating the 0.8 thou needed.  Once again, done in two passes.  The swarf left on the tool tip itself and the bits left on the thread was pretty much all that was taken of on the last spring pass:


A quick test with the closer nut, and it fits very closely but runs smoothly up and down the thread:

<a href="http://www.youtube.com/watch?v=_oFppeWqcUw" target="_blank">http://www.youtube.com/watch?v=_oFppeWqcUw</a>

The M15x0.75 section followed using the same procedure, and I stopped there.  Most likely I won't get back into the shop till this weekend to continue:


Kind regards, Arnold
Building an engine takes Patience, Planning, Preparation and Machining.
Procrastination is nearly the same, but it precludes machining.
Thus, an engine will only be built once the procrastination stops and the machining begins!

Offline Steamer5

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Re: ER11 Multi-purpose tool
« Reply #1 on: November 06, 2013, 08:35:52 PM »
Hi Arnold,
 Sitting up & taking notice! Lots of hints & tips on how to on the screw cutting front, for those of us that either haven't yet done any or are wondering "what the hell did I do wrong here?" camps. Looking forward to part 2

Cheers Kerrin
Get excited and make something!

Offline Don1966

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Re: ER11 Multi-purpose tool
« Reply #2 on: November 06, 2013, 11:32:49 PM »
Hi Arnold, since this tool is for a myford I will be tuning in and see how it all unfolds.

 :cheers: Don

Offline swilliams

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Re: ER11 Multi-purpose tool
« Reply #3 on: November 06, 2013, 11:45:19 PM »
Nice Arnold

What is the purpose of the second larger thread?

Steve

Offline EmanMyford

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Re: ER11 Multi-purpose tool
« Reply #4 on: November 07, 2013, 06:00:53 AM »
Hi Arnold, looking great. Thanks for doing such detailed explanations. I know it takes allot of time to write and explain but all of us are learning so much from your efforts  :cheers:. Much appreciated. I will also follow this one closely to use on my Myford.

Kind Regards.
Ewald

Offline arnoldb

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Re: ER11 Multi-purpose tool
« Reply #5 on: November 10, 2013, 11:22:06 PM »
Thanks Gents  :)

The tool isn't Myford specific - in fact, it will be used mostly on the mill and the small lathe.  It's harder to try and describe all the functions it will fulfill than to show it, so once it's finished that should be revealed.

Technically, I could just have used one long M14x.75 thread; there's no reason for making the second section larger.  That's just me having fun screwing a round  ;) .  The bigger section will be for an adjustable collar ring - that will also become more evident later in the build.

On with the gory details then...

Yesterday I drilled a 7mm hole in the spindle, but not all the way through - I left 20mm at the other end on purpose.  Then I set the top slide at 8o using the scale on it to bore the taper for the ER11 collets.  From making previous ER collet chucks I know that the scale on my Myford is accurate enough.  I wouldn't trust the scale on my mini lathe though, so, if in doubt, rather use a method like Chuck showed while making his ER chuck for the mini lathe.
Once again, it's very important to set the cutting tool tip to center height when turning or boring a taper.  If it's too high or too low, the taper does not end up at the same angle as is set on the compound.  Then I honed up the cutting edge of a small boring bar, and bored the taper:

(Clicky-piccy) By honing the HSS cutting bit on an oilstone, it's really easy to get a very good turned finish in silver steel - the little strings of swarf lying on the cross slide came off while doing rough boring, and the swarf left on the tip came from the last very fine finishing pass.  I turned this dry, but as always for turning steel, some cutting fluid will help to get a good finish.

A trial fit with a collet - I very nearly bored it out too large:

On the ER11 series, this is OK, as they go up in 0.5mm steps, so don't need a lot of moving space to clamp down on workpieces.  On my ER25s though, this would have been too deep; they go in 1mm steps, and need more space to clamp down on workpieces at their "small" end.  It's actually fairly easy to determine the hole size needed for the different ER series collets.  The number gives away the size of the taper at the mouth of the collet chuck in mm.  So, the hole for ER11 should be 11mm, 32mm for ER32 and so on.  In practice, it's quite difficult to measure the hole size because of the taper, so I don't bother.  I just check how far a collet sits out of the chuck-in-making; if the distance from the chuck-in-making to the closest edge of the groove in the collet is about the same as the distance from the nose of the collet to the closest edge of that to the groove, it's about right.  Works a treat on my ER11 and ER25 collets; but I don't know how well that cheat will hold up for the other sizes.

I removed the workpiece from the 4 jaw chuck, reversed it, and clocked it up true in the 4 jaw chuck again.  It was faced off at the end, then I drilled a 5mm hole through to meet up with the 7mm hole already in the workpiece.  The end got a decent chamfer with a countersink (that will make things easier when in practical use) and tapped the hole M6 all the way through to the 7mm hole.  I also turned the OD down to 15.87mm (5/8") for a length of 9.3mm (that's just under 3/8").  This is the only Myford specific part of this build, and is so that I can use the Myford's change gears on it as indexing wheels:


The finished spindle:


With a collet and closer nose fitted, gripping a bit of 2mm bronze rod:


Next up, the collar for the thicker bit of threaded section on the spindle.  I chose a bit of phosphor bronze for that because it will become part of a bearing surface in use later on.  I turned off the crud on the outside, faced it, and bored it to an ID of 14.25mm.  This isn't a super-duper high precision job, but I used a telescopic bore gauge to test the size.  The telescopic gauges needs a certain "feel" in use, and that can't be taught or described online; it's something one must experiment with in the shop and practice on occasion to keep in touch with.  A simple project like this is a great way to start off with or keep in practice for when the "real thing" comes along - both in terms of measuring and machining:


Pretty much dead-nuts on - the parallax in the photo makes it look off:

Note to self - build a micrometer stand on a rainy day...

Once again, the workpiece got a generous chamfer at the lead-in to the bore - at the approximate angle the thread would start.  Not really needed; just a little "finishing touch":


Next up, more threading.  I checked a home-brew boring bar with a bit of HSS mounted in it; pulled this out of the toolbit stockpile.  Spot on, and also at a nice 90o angle with the boring bar:


I set that up in the lathe.  For internal threading, I prefer to mount the toolbit upside-down and facing the back of the lathe.  That means I can screw-cut with positive in-feeding of the cross-slide.  The chips coming off falls away from the cutting bit rather than piling up on it, and I get to see what's happening at the start of the cut as well.  This is purely personal preference.  The same rules apply however which-way one choose to do internal threading.  The toolbit cutting edge must be set dead on center - here I'd just set it to center height with the height gauge shown earlier in the thread:


As I'd already established earlier that the cutting tip was at 90o to the boring bar, I just set the toolpost in line using a small bar chucked up in the tailstock chuck:


At this point, I was ready to start cutting the thread, and with the final check I fell flat on my face  :lolb::

No way that cutter will enter the hole  :-X

So, I needed to make a new cutter - that would be a bit of work and shop time was nearly over, so I stopped work there yesterday.


Today was mostly taken up by painting a trailer, but I managed to squeeze in some machining.  First up, I needed a threading cutter to fit a smaller boring bar.  I started off with a bit of 4mm round HSS blank; I buy these a couple at a time and use them as needed.  It works out as a nice and cheap way to make toolbits:


A couple of minutes with the bench grinder, and I soon had the required angle ground on the tip, as well as a flat section at the front.  Some more minutes with the oil stone in the top of the picture, and it was nice and sharp; the cut line in the paper parallel to the fishtail gauge gives an indication:


It's much easier to grind up and hone a good cutting tip when the "parent stock" is nice and long as in this case.  The next step is to get the newly ground tip off the stock.  A couple of nicks with a Dremel cut-off wheel helps:


On to the big vise, and a pair of pliers and a bit of cloth are needed for the next step:


Simple really; HSS breaks like glass.  Grab it with the pliers, cover the whole lot with the cloth, and snap it off.  The cloth is a safety device; if splinters come of while breaking off the HSS, it will catch, or at least slow them down.  I usually don't find splinters flying away:


All mounted up in a boring tool I prepared a couple of years ago  ;):


I repeated the process of mounting it on the lathe described earlier; and did a final check:


The corner at the top right of the toolbit might still have interfered with the cut - quite possibly ruining the quality of the threads, so I ground that off:


Touched the toolbit to the back of the bore of the workpiece and noted the reading on the crosslide dial.  Some simple math was used to get the total depth of cut needed (all in thous):


And finally, cut to depth on the workpiece; the bronze is easier to cut and actually "likes" the geometry of a threading tool, so I was quite aggressive on these cuts.  10 Thou initial, another 4 thou, and a final "just under" one thou clean-up pass:

 :-[ Apologies; cruddy photo; I missed the focus on the threads...

The spindle screws in nice and smooth - so I'm a happy chappy:


That ended today's shop session.  I was hoping to get this device done this weekend, but painting a trailer took away most of my shop time.

Kind regards, Arnold
Building an engine takes Patience, Planning, Preparation and Machining.
Procrastination is nearly the same, but it precludes machining.
Thus, an engine will only be built once the procrastination stops and the machining begins!

Offline gerritv

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Re: ER11 Multi-purpose tool
« Reply #6 on: November 11, 2013, 12:41:46 AM »
Quote
Note to self - build a micrometer stand on a rainy day...
I had to look it up, we visited Walvis Bay/Windhoek in Feb 2010 and from that wonderful experience didn't think there would be much rainfall there. But it seems Jan-Mar is quite wet.
I enjoyed climbing Dune 7 and also got hooked on droewors and biltong. Bought lots to enjoy on the rest of our cruise! http://travels.psgv.ca/thurs-18th-feb-walvis-bay-namibia/

I'll be making an ER16 collet holder for my Taig soon, following along here for an excellent education.

Gerrit
Don't confuse activity with progress

Offline swilliams

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Re: ER11 Multi-purpose tool
« Reply #7 on: November 11, 2013, 02:03:46 AM »
Nice Arnold! Looking forward to seeing how she turns out

Steve

Offline Ginger Nut

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Re: ER11 Multi-purpose tool
« Reply #8 on: November 11, 2013, 07:16:47 AM »
Arnold you have me glued to my seat  :atcomputer: Having picked up a few Myford ER16's recently with out the closer or push tube this thread is invaluable to a novice like myself.

Offline arnoldb

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Re: ER11 Multi-purpose tool
« Reply #9 on: November 11, 2013, 05:22:23 PM »
Cheers Gerrit.  Walvis Bay is dry; it rains a maximum of about 25mm per year in the desert - and even less in many spots.  Here in Windhoek, it's not that dry; we get about 800-900mm per year, and most of that is from Jan-Mar.  Towards the North West of the country, it's a bit wetter, with areas getting up to 2000mm per year.  Droewors, Biltong and Tafel - those qualify as basic foodgroups here  ;) .

Thanks Steve  :)

Ginger, thank you  :) .  If you're referring to the collets you got that you you mentioned in "Need to be Nosey and Pushy", those are actually #2 Morse Taper collets (MT2 for short); they are quite different from the ER series.  I'm mentioning this, as I wouldn't want you to start making things based on ER dimensions.  Just for reference, below is a photo with ER11 (left) and ER25 (right) collets:

Don't worry though; all the dimensions you need are available - if you need it just ask. 



There's something I should mention for everybody's benefit here regarding screw cutting.

All the methods I described so far are pretty generic for any type of screw cutting and not limited to bits 'n bobs for collets. 
There are quite a few different methods that people use - and these can sometimes be hotly contested as to pros and cons, especially when it comes to plunge cut with the cross slide like I do or setting the compound at a slightly smaller angle than the thread and using that to feed in.  What many of these discussions don't consider are that there can be machine limitations, for example, ML7 owners will rarely be able to set the compound to the needed angle to feed with it  ; the standard ML7 compound simply cannot do it.  That pretty much leaves us ML7 owners up to feeding with the cross slide. 

Have a look around at the different methods people use, try them out if you can and don't be scared to adapt them to your own needs.  What works for one person might not necessarily work for yourself.  A lot depends on getting to know your machines as well; simple non-critical projects teaches one a lot about your machines.  We are in a hobby environment and there should be no such thing as a fixed deadline to complete a project by - I tend to follow L.H. Sparey's advice from "The Amateur's Lathe" in my shop: "If in doubt, slow down".

Unfortunately I don't think I'll get back in the shop after work in the evenings this week; there's a couple of social commitments, as well as a final push needed to finish off some "work" projects.

Kind regards, Arnold
Building an engine takes Patience, Planning, Preparation and Machining.
Procrastination is nearly the same, but it precludes machining.
Thus, an engine will only be built once the procrastination stops and the machining begins!

Offline Tennessee Whiskey

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Re: ER11 Multi-purpose tool
« Reply #10 on: November 11, 2013, 07:20:22 PM »
Social commitments. Ok, who is she and we want piccys :lolb:. Thanks for this thread. I have a Levin watch makers lathe with a full set of collets and accessories. You have got me to thinking about making a collet holder for these collets, as they go down to almost nothing in bore size. I think a round one first. Then it could be chucked up in a 3 jaw. Then a square and hex block. We're talking "itty bitty" bolts :Lol:

Whiskey

Offline arnoldb

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Re: ER11 Multi-purpose tool
« Reply #11 on: November 24, 2013, 06:37:03 PM »
Eric, 'tis the time of the year where companies over here have their year-end functions and start winding up things ahead of the "Summer Holidays" (we have those in December in the Southern hemisphere).  So most of the social commitments were/are centered around client invites, so even while it's fun, I have to keep things professional  ;) .  +1 For chucking things up in the 3-jaw - but I'll forgo the square and hex blocks for my small collets for the "itty bitty" bolts (and screws, nuts, gears etc); in fact, that is exactly what this little build is about.

Last weekend was spent on "work" work; in fact, things have been hectic between attending parties and meeting deadlines.  A lot, if not most, of those are successfully out of the way now, and as a treat, I had the weekend available for sleeping and machining  :whoohoo: .

On to machining for a change.  When I left things, the collar-in-making was still sitting in the lathe, and the first job was to part it off.  Phosphor Bronze can be a bit of a trial to part off (for me anyway), but I've found that a broken HSS jigsaw blade re-shaped into a parting tool does a very good job.  I stopped at this point:

It's about 1 mm away from final part-off, and before continuing with the parting cut, I used a small triangular needle file to chamfer the outside edge of the cut.  This was VERY close to the chuck.  I regularly use files while working on the lathe - but one MUST be careful.  Check first with everything switched off if there's enough clearance; the last thing one want is for the file or fingers to get caught
on the chuck jaws. 

I wanted to add the chamfer at that point - if it wasn't done then, it would have taken some manual filing or a similarly close-to-the-chuck operation later on.

After finishing the parting cut, I mounted  the workpiece in the chuck to face the other side, and to add a chamfer to the threaded section.  As it was a very close fit on the arbor threads, the parting-off process raised enough metal that it wouldn't screw easily onto the arbor anymore.  So this operation both neatened up the parted face, as well as removed the "raised" metal from the parting process on the inside of the threads:


My old 3-jaw chuck isn't accurate, concentric and parallel any more, and mounting a workpiece in reverse like this after the parting cut means that the face cut will not be accurate. 
The bit of the workpiece at the inside end of the chuck at this point in time is important, and was machined fairly accurately, so I marked the outside inaccurate face with a permanent marker before removing it from the chuck - otherwise things could get confusing later on:


I'm freelancing quite a bit during this build...  To check what would work as a tightening screw on the collar, I just eyeballed an M3 cap screw on it:

Not ideal, but it'll do. It's what I have floating around.

Before carrying on, I stamped a letter "F" for "front" on the end marked with the permanent marker.  The blue dot will disappear quickly, and I do need a permanent reference.  The stamp could really have been centered better though  :embarassed:


Off to the mill.  I used the edge finder to locate the Y center point, and then a 6mm end mill to mill out a pocket for the M3 cap screw head.  Rather than plunging in the mill from the top, I fed it in from the side with the quill locked.  This took care of two potential problems while milling bronze.  Bronze is a "grabby" material, and when plunging in from the top with quill feed on a mill/drill like mine, it can easily grab and over-shoot, as a sharp cutting bit tends to pull into the material.  The other problem with feeding in from the top is that most cutters does not cut truly flat on a plunge; they leave a very slight cone upwards toward the center of the hole when plunging.  This makes it less accurate to start an accurate hole from there:


A 2.5mm drill followed:


Tapping it M3 was a doddle:


I slit it with a 0.5mm saw - normally I'd have used a 1mm one for a job like this, but the 0.5mm one was already mounted on the arbour and I was just my own lazy self and couldn't be bothered to change the blade:


To cut the thread clearance for the screw in the section above the slit, I used a 3mm end mill.  There was very little material to remove, so just a small chance of grabbing:


One thing I'd noticed in the past when making similar collars from phosphor bronze, is that they do tend to close up once slit.  This time it was more of the same - it would not easily screw onto the arbour again.  I actually had to use a thin screwdriver inserted in the slot and a whack with a small hammer to make it open up a bit to be a good fit on the threads.  After that, it screws on easily again, and a light turn on the screw clamps it down totally.

The completed collar:


And where it goes:


Next I scrounged around for some bits and bobs of steel - I'm pretty much making do with what I have floating around rather than buying material:


A while ago, a package arrived from Richon Tools in Hong Kong.  The main reason for the package was two diamond dressers to be used on the tool & cutter grinder, but seeing as they had 16mm roughing end mills on special at the time I ordered, two of those also found their way into the shipment.  I've never used one of these beasties, but it is quite a pleasure to use:


A bunch of fly-cutting ensued.  First a fairly deep (0.5mm) and rough pass to get rid of mill scale from the HRS bits - using a left-hand carbide tipped lathe toolbit as the cutter at 350 RPM.  :


Followed by a finer in-feed (0.1mm), a higher spindle speed (850RPM) and a slower rate of feed:

Looks a bit cruddy, but it's actually quite smooth.  The biggest problem is chips finding their way back onto the workpiece while fly-cutting, and stuffing things up.

It's been extremely hot and dry here of late, but on Friday some humidity moved in - making things hot and humid.  Amidst burst of thunder and lightening, the clouds finally opened up and some very welcome cooling rain fell - I opened the shop's roller door to get some of the cool air:


The dogs didn't seem to like the rain - and the yellow bitch is terribly scared of thunder, so they joined me inside:


On to those bits of HRS...  I intended to bolt most bits together with M6 cap screws, but digging through my selection, there was not enough of suitable lengths to get the job done.  Well, it was Saturday afternoon, and there was no way to get more screws, so I looked at alternatives.  Silver Solder ? - easily done, but at the going rate, that's an expensive option and I'd rather keep my stock for building engines.  Braze ? - I've got the equipment but never used it before.  There's always a first time.  Well, when I got to the PPE, the goggles wouldn't fit over my glasses.  Bah.  Suitable brazing goggles added to the shopping list.  So the only option left was stick welding.  I tend to weld chicken-sh1t with that, but practice might help.  To prepare the bits, u used the small angle grinder to add generous chamfers to the needed sections of the workpieces:


Then used a rusty  :-[ square to align the bits a bit before clamping them up:


The lot was moved to the big vise:

Hmm...  I need a couple of smaller G-clamps - or even better some larger toolmaker's clamps...

After removing the combustible bits that was lying on the bench (cloth, newspaper etc) some welding ensued:


Followed by some grinding to try and hide the evidence:


Fly-cutting the one side came out OK:


But the other side revealed that I'd missed the mark a bit  :lolb: :


At that point, I left things for Saturday; the electricity had gone out a couple of times with the thunder storm, and it's no fun getting caught in the middle of machining operations...
So I closed shop, poured a beer and went and sat on the stoep (porch) and enjoyed the rain.

This post is long already, so I'll take a breather  :DrinkPint: before continuing and rest your eyes.

Kind regards, Arnold
Building an engine takes Patience, Planning, Preparation and Machining.
Procrastination is nearly the same, but it precludes machining.
Thus, an engine will only be built once the procrastination stops and the machining begins!

Offline vcutajar

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Re: ER11 Multi-purpose tool
« Reply #12 on: November 24, 2013, 06:51:12 PM »
Arnold

I really love your posts.  They are so descriptive.  Just like a diary.

Vince

Offline Tennessee Whiskey

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Re: ER11 Multi-purpose tool
« Reply #13 on: November 24, 2013, 07:26:16 PM »
Ok Arnold I'll let you off on the end of year thingee. I'm still betting she's dark and blonde 8). I taught welding for a few years. The greatest incentive to improve their welding skill involved a very heavy 9" side grinder and a half round bastard file (which was usually pretty dull). We called the grinders "South Georgia Milling Machines". Just focus and watch the puddle closely. Set your travel speed and rod angle by watching the undercut fill with the filler material. The closer the arc the better. I'm following along as I also have some ER? Collets and an R8 arbor that came with a milling accessories kit when I bought my mill. Haven't used them, however, now I'm getting ideas.

See ya boy,
Whiskey

Offline AussieJimG

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  • Bywong, NSW, Australia
Re: ER11 Multi-purpose tool
« Reply #14 on: November 24, 2013, 09:02:27 PM »
Thank you Arnold, I am reading and learning - particularly about making tools for threading.

Jim