Model Engine Maker
Supporting => Tooling & Machines => Topic started by: Chipswitheverything on January 24, 2023, 11:08:25 AM
-
The castings for my Mark 2 Quorn grinder were bought from MES / Ivan Law, back in 1982, along with the motor, wheels and dresser. Total cost was about £170, the Mark 3 one recently offered by Hemingway kits is about £700 for the equivalent, but I don't know if I had a bargain back then or not!
Haven't got a lot of photos of the very protracted and occasional work on the build, a lot of it was pre digital camera. Almost all of the components are now made, other than some items like the dedicated bolts and washers that are needed to assemble the ball ended levers to correct location, and there is the final assembly and general tweaking to be done. Got all those ball levers, and the wheel collets and tool holder done this autumn, just before it became too cold.
In the last few weeks I have filled, primed and wet and dry rubbed down the machined castings, four sessions of that, then a couple of coats of Tom Senior green paint ( I had some! ), similarly rubbed down; and now a final green coat. In truth, they are not anything like perfect now, but for a working Quorn they will do, I think. Any straying paint will be cleaned up in the assembly. With my workshop basking at around zero degrees, and the new paint benefitting from sitting on the radiators indoors for a while anyway, the putting together will have to wait for a bit.
I have a little query about the electric wiring, when I am later able to do it. I will follow the diagram in Prof Chaddock's book, as per the photo. I have a centre off, two way switch to suit. The diagram shows two white leads coming from the large capacitor: mine as supplied has a brown and a blue lead. Shown in other photo. I get the feeling, but would be glad of confirmation, that I can wire these leads as if they were just the two undifferentiated white leads in the diagram, and that which goes where will only affect the running direction of the motor. And can be swopped if necessary to make the direction accord with the switch?
When the Quorn does finally come together as a machine, I'll bung up some pictures and some build photos . Dave
-
Hi Dave,
That looks very smart 8)
If you read the print on the outside of your capacitor it explains that to reverse the direction motor runs you reverse the leads on the starting capacitor. You will get the same effect by swopping over the two wires for the running winding.
Jo
-
Looking forward to final assembly and use. I like the color very much! :ThumbsUp: :popcorn: :cheers:
-
Hello Jo, thanks for your comment, ( and the encouragement from vtsteam as well ). What you have said about the wiring , and the capacitor printing, not that easy to read all of it, indicates to me that I will be OK to wire as I planned to do. Dave
-
Nice paint job! And LOTS of handles! :o
You're going to have a very nice Quorn there! :ThumbsUp: :popcorn:
Kim
-
That all looks very fine. Excellent choice of colour, IMHO.
-
I am not at quite at the same stage as you on my Quorn build, but as I also have a tin of Tom Senior green I was going to use that on my Quorn as well. Tomm Senior green looks good doesn't it !
I purchased a mk2 set of untouched castings and I am building mine to the mk3 instructions and drawings. I am using the split cotter arrangement rather than slitting the castings.
To power the thing I purchased from the well known auction site a parvalux 3 phase motor and will use this control speed, forward and reverse direction.
Good luck with your Quorn !
-
Thanks for the comments, and appreciation of the colour! If I was making the Quorn now, then I would have adopted the cotter arrangement rather than the slitting way : the big lumps were all done way back and soon after I had bought the castings, the discussions on the Quorn builder's forum and elsewhere as to the merit of using cotters had not come my way. I did have some closure of the bores after the splitting was done, a bit of a nuisance. When I built a second pillar tool and mini drill some years later on, I did use brass split cotters on all the bores in that, as GHT had specified, and they were very satisfactory.
When I machined the bronze casting for the Quorn tilting base a few years ago, I did include a split cotter in that component, and also did the well-known mod. to the rotating bolt, using the conical seatings and tapered / split collets that make it much more secure. Dave
-
Yes I did the mods to the tilting base and the rotating base was built up from two separate slabs as per Hemingway's mk3 design.
The last real big component on my build is the spindle which to be honest I have a lot of trepidation about......
I also built GHT pillar tool and drill attachment as well as the headstock and vert dividing head attachments.....all have been used on the build of the quorn
-
#Dave#
You have created a beautiful machine.
Congratulations for the perseverance over many years to complete the construction of the Quorn.
I did not build the Quorn, but the "Bonelle". It is based on the same construction as the Quorn, with small differences. It is built without castings, which was much easier for me at that time.
In the meantime I have made all kinds of accessories for it. Most of it is from the book by Prof. D.H.Chaddock.
-
Hello Bruno, thanks for putting up the pictures of your very well equipped Bonelle, that looks very capable. I know that they tend to be popular in the USA also, here in Britain the availability of the castings for the Quorn makes them a rarer option. See that you have made the spiralling head : I machined up the casting bores while making the work head, but as I've not much thought of making cutters from scratch, I'll leave that for now, see if I want it at some time...
Right now, after a rather cold spell, I have got back in my workshop again and am doing some work on trying to get the Quorn assembled, making the special bolts for the ball levers and fitting them to the specified positions, and finding a few things that need a bit of fitting work. When I tighten up the "tilting lever" that sits on the end of the sliding workhead base, the fit of the lapped bore and the precision ground bar is such that the thing locks up, so I will need to locally relieve the fit where the lever squeezes... I can see that there might be a fair amount of playing around with discoveries like that. Dave
-
#Dave,
Even after many years, you will still find places that can be optimised. At some point, a sharpening device for drills will be added.
I made this not too long ago.
-
A very nice set of finely sharpened drills, Bruno, a pleasure to use, I'm sure. Looks from the picture as if some of them have been sharpened by the four-facet method that Prof. Chaddock gives some details of. I might try that somewhen, though as you have found it worthwhile to make the drill sharpening jig, I'm thinking that they are better done in the conventional way?
I spent a while doing some more odd jobs to bring the build along yesterday : though I have made loads of notes and lists over the years of building, and scribbled stuff all over the drawings , I was caught out by a few items that I had overlooked and needed doing. Two steps forward and one step back...! Dave
-
Yes, Dave, that's how I usually feel about such projects. You look at the drawings and think you have understood everything. You start working and then you reach a point where you look at the drawings again and discover things that you hadn't noticed before.
As long as you notice these things in time, you can still react to them. If, however, the insight only comes after the parts have been finished, then you have to make one or the other part again, or live with the mishap.
Bruno
-
Here is a bit of update on the Quorn tool grinder, down the final straight now and maybe with the chequered flag dimly in view...
Just to preface my very long term messing about with things Quorn, which explains a little why it has gone on for far too long.
Some years ago, 7 or 8?, a friend who was, and to an extent still is, equipping a very comprehensive model engineering workshop with excellent tooling ( so far none of it ever used at all...! ) bought not one but two s/h Quorn grinders , Mark 1' s, via the well known auction website. When I saw them,( and they definitely looked a bit dodgy, "curate's eggs.." ), in my naivety and optimism, I thought that, with my Quorn a long way off, it might be a route to usefully getting milling cutters sharpened if I spent a few evenings sorting out a useable Quorn from the bits of the two..
It was a nightmare, as soon as I sorted out one problem, including re-machining some castings, I found a bigger one. Even the electrics disintegrated later on! I should have stopped after a short time, but ended up too deeply in to feel like handing them back and saying, "best of luck!" Eventually, weeks later on, I got the conglomerated and largely re-built machine working pretty well, and set it up and experimented. Quite a lot..!
After that, I reground every end mill and slot drill needing a tweak that I had here, along the flutes as well as doing just the ends. That was about 250 cutters, and I did a little batch for another model engineering friend while set up.
Made up some screwcutting tool blanks also. That machine went back to my friend ages ago, for the spiders to explore... Don't think that I ever took any photos of it.
So the position now, with my Quorn nearly ready to be used, is that I haven't really got the need to use it all that much! What with having a fair quantity of other milling cutters that were new or sharp to begin with, I would need to be pursuing the hobby with much more fervour than I have generally mustered, to be blunting a good proportion of the available cutters...
But, it will freshen up lathe tools very helpfully, deal with items like home-made S/S counterbores, and do the other bits and pieces that Prof. Chaddock gives details of.
I'll make a few accessories up in a while, setting pins and cutter holders. As I mostly use "Arrand" style of home-made holders for the milling cutters, ( the 2MT Autolock that I have having a pretty large overhang, nice though it is ), I will probably make simple 1" arbors, double-ended, with closely fitting bores for holding cutters to be ground. Not worry about a collet system; I have quite a lot of 1" precision grd. steel bar that may be useful.
The machine still needs setting up and aligning, and the several index lines marked for the scale protractors. I'll bung up some photos, and maybe add a bit more later. Dave
-
I know a few guys that have bought / made / finished Quorn and other tool grinders, and they all say the same - once you have sharpened your collection of cutters the tool grinders don't get a lot of use. It occurred to me some time ago that adding a column-mounted table to do surface grinding as well as cutter grinding would make the machine far more useful. Could be an X only table, or XY, and would need an elevation mechanism to vary height between the wheel and the table. If light passes are taken during use, and table size kept relatively small, the construction would not need to be heavy duty, and probably would not cause any bearing issues in the spindle. Just food for thought. :cheers:
-
Wow! That's really nice looking! :ThumbsUp: :popcorn:
I'd say it's a great piece of equipment to have! It will definitely come in handy from time to time.
Kim
-
Very nice looking machine, well done!
-
Very nice looking job. To me, the earlier cast Rotating Base looks so much better than the later bolted barstock arrangement.
-
Thanks for the appreciative comments. Charles, I agree that the all in one rotating base is a better looking entity, and although it has been viewed as one of the trickier parts, maybe because of the undercuts, I found that the dedicated double-ended tool detailed by Prof. Chaddock, which I made up as described, did a great job in forming the grooves easily.
The Prof. did give some details of an arrangement , in a later article, to rig the wheelhead up on a milling machine quill to use as a simple surface grinder, as Cnr suggests. I suppose the big problem of using a mill is the generated gritty dust, so a separate table arrangement might be quite a good idea.
As Kim says, "handy from time to time" is certainly what the machine will be; and I'm not too worried if it doesn't now come in for all that much use : - it's just been nice to see it go from a big box of bits representing many hours of work, but useless just as a growing pile of components, to a finished entity, rather the same as it would be if it was a model that finally came together. Dave
-
A few further notes: have done the alignment tests with the dial indicator and the test bar made to fit the 40 degree taper spindle nose, various turn around tests. They all went satisfactorily, and have now got the index lines marked on the components needing that. Also have made up the simple style of cutter holders for four Imperial sizes of shanks. Metric can be done later if the need arises, but with such a glut of sharp cutters already , may not be soon.. Also have made the various setting pins used with the grinder, waiting some hardening and tempering in a batch.
The gunmetal casting for the tilting bracket holding the workhead is one of those components that has a reputation as being rather awkward, or a fascinating challenge depending on how one sees it...
Here are some photos that I dug out showing some operations on the casting. I modified it a little in order to use a split clamping bush to secure the rotating base rather than slitting the casting as in the original design. Hope that these may interest any builders contemplating a Quorn, or yet to do the bracket. Dave
-
#Dave#
very nicely documented,
I am looking forward to more photos.
-
Thanks for your comment and interest, Bruno.
Here are some pictures of the work on the Rotating Base, a steel rather than iron casting: which seems to have been modified, supposedly to be easier, in the recent Hemingway design for the Mk III. However, the original design is neat and compact, and the Professor's recommended home-made tool for the grooves works very well. There are a lot of operations to be performed on this casting, ( as with the Tilting Bracket ), admittedly it does get a little fraught as a lot of time is invested in the thing, but pleasing if it goes well. Dave
-
Interesting to see how you are machining those critical components on the Quorn. I use my Myford S7 and Emco following the instructions in the Profs book as well as the build instructions from Hemingway.
I am built the rotating table using the "built up" method I.e. the mk3 version and I agree the one piece casting does look neater.
I also totally agree that as more time spent on machining one part increases the stress levels as the fear of stuffing it up and hours of careful work is scrapped!
Almost all major components made now on my Quorn, just need to finish off the work holding casting and the final part is the spindle. Not sure if I will bother finishing off the spiralling attachment part though.
I bought the Quorn castings from a fellow model engineer they are the mark 2 version and I am modifying it and updating it to the mk3.
Good luck with the build !
-
Thanks Del, glad that the methods interested you, though it seems that you are just about through with most of the build now. I'm completely done too, (for now, anyway..), the machine is all together and working, as per the photos of it earlier, and the handful of setting pins and odds and ends, some cutter holders, are done now. I need to do the dressing of the four grinding wheels. Outside the workshop, on a Workmate... No use today, pouring with rain the whole day!
The spiralling casting, as I mentioned, has just been done with the two bores, it was easy to do at the time when the workhead jig, for the bores, was set up on the lathe. But it will probably remain unfinished and unpainted...
If you have kept a record, be interested to see some photos of your machining of various components, we all have our individual ways..! Dave
-
From the photos it seems you have also made a fair proportion of the stuff in the George Thomas books. What's next?
-
I made some of the accessories shown in Mr. Thomas' book for my Bonelle as well.
The jig to resharpen threading dies and the part to resharpen saw blades (bandsaw blades).
Unfortunately, I have not taken any pictures of the fabrication. Only the finished accessories I have photographed.
Accessories threading die sharpening.
-
Accessories saw bands sharpening.
-
Thanks for featuring the two unusual accessories, Bruno : I would think that not too many Quorn makers have made and used those particular devices. I may have a few dies that could do with a bit of improvement at some time. ...
Charles, I recall that you also had some personal association with the late Geo H Thomas: in fact I found the note among the discussion of that gentleman in this forum : https://www.modelenginemaker.com/index.php/topic,10932.msg253352.html#msg253352 ( in case that might interest other members ).
And that you also have made quite a few of GHT's excellent tool projects.
Don't think that I will be venturing on other designs from that source, there are some , like the index line engraver, that I could have found useful if I'd made it years ago, but would probably not exploit much if made now. Some of my home made tooling has come from designs by J A Radford. I have a few tooling items, like the GHT Bending Rolls, that came to me ( bequests, sadly ) from other model engineers who had made them. Some of the most useful GHT items made up , I have found, are the comparatively small bits and pieces, like the designs for various boring tools and holders, ditto for screwcutting tools, little parting -off tools and so on, they tend to be used in most workshop sessions. Dave