Author Topic: Building the Minimag  (Read 30339 times)

Offline Bogstandard

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Building the Minimag
« on: January 30, 2011, 06:01:21 PM »
At last, I have started to be able to move on this little project.

For anyone who doesn't know what this is about, I suggest you have a look at this

http://madmodder.net/index.php?topic=4168.0

I received the kit about ten days ago, but building it has been held up by a couple of jobs in the shop and a few personal things.

I am not building yet, I am going to introduce you to the kit first.

I have got to say, this is a VERY complete kit, absolutely everything you need to make the unit except for a bit of superglue, a dab of loctite, and of course a bit of machining.
It is made up from a couple of different standards of fixings, all metric with just one bit of ME threads. But I suppose this is to take advantage of the cost of parts involved as it might be both cheaper and easier to source something like metric bearings and fasteners rather than imperial ones. The plans are also marked up in both standards, where needed. Things like that don't bother me at all, just take a bit more care as you do things, one good part at a time.
There is even a little bar of tufnol (or something similar), spring steel flat and a couple of tungsten rivet contacts supplied for making the points setup, as I said, everything is included.

The lighter in the shot gives some sort of scale.




I was at one time going to make one of these from scratch, from the book by the late Bob Shores, but the things that always put me off was winding the coil and making the punches for all the laminations (both coil and magneto). For a one off, a great deal of work.

No trouble on that score with this stuff. The coil is a work of art, fully potted, moulded to shape and sealed, not like a lot of model coils I have bought and used before, with their outer casings made from rolled cardboard, then all potted up with a soft wax like substance. This one really is the bees knees.

The strong magnet rotor is the same quality, fully potted and machined to size.

The laminations, are again, very well made, crisp cut, and on my kit, supplied as two sets, one left hand, one right hand.

The final main bits are the two roller bearings for the rotor shaft to run in.




The main part of the machining is making up the support block from the lump of ali supplied.
If care is taken, and the instructions followed, this should hold no terrors for anyone. It looks difficult, but if broken down into stages, it will emerge from the block like magic.




I will be following, as close as possible, the pre production build sequence and plans that Julian has provided me with. He has requested that I show no dimensions on this pre production build, just in case things change a little before it is released to the public. I fully agree with what he has asked me to do.

I will also be taking it a little deeper, giving a few hints and tips as I go along, so it should make healthy reading even for the novice, even if they are not needing one of these units.

I will be doing this in the same regime as I am building the flame licker. Most days, with a little luck, four hours work, if not, then two. I expect it to take around four to five days to complete, as I am a fairly slow but meticulous builder.

I do hope you follow along and enjoy it.


Bogs
« Last Edit: February 06, 2011, 04:40:47 PM by bogstandard »
If you don't try it, you will never know if you can do it.

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Offline ozzie46

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Re: Building the Minimag
« Reply #1 on: January 30, 2011, 06:41:47 PM »
Got my seat picked out and patiently waiting.   :coffee: :coffee:

  Ron

Offline Dean W

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Re: Building the Minimag
« Reply #2 on: January 30, 2011, 06:59:26 PM »
I think I'll watch!  I don't have a need for one (now), but they are kind of like a black magic box.  Everyone
wants to know the trick to the magic.  : )
John, I think he has an error line in the drawing you show.  The line that goes between the two uprights, on
top of the partially angled/partially bored piece that sticks out the front.  Maybe that line shouldn't be there.
That is, if the top surface it lies on is flat.  He may want to know, (or I'm mistaken).

Dean
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Offline madjackghengis

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Re: Building the Minimag
« Reply #3 on: January 30, 2011, 08:37:08 PM »
Hi John, glad to see the beginning of this  :whip: I was looking at what Bob Shores has put out as well, I believe I would like to be able to end up with one for the radial engine in the end, I think it can be done with a distributer attachment and some gearing.  I want to see how small this one you're building works out, and make a guess at whether I can use the basic principles.  I hope you can give some idea of relative size when it is all together. cheers, mad jack

Offline jim

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Re: Building the Minimag
« Reply #4 on: January 31, 2011, 01:32:25 AM »
i'll be following this with interest.
if i'd thought it through, i'd have never tried it

Offline NickG

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Re: Building the Minimag
« Reply #5 on: January 31, 2011, 07:07:31 AM »
I'll be watching too.  :thumbup:
Location: County Durham (North East England)

Offline Bogstandard

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Re: Building the Minimag
« Reply #6 on: January 31, 2011, 08:05:45 PM »
Now the basic kit intro is out of the way, could I please ask the members, unless it is directly related to this build, not to post things like, 'I built one thirty years ago' etc etc, could you please leave that to the very end, after the build is completed, and we can then discuss it.
If there is a question about techniques or procedures then please ask, but again, as this is a testing build for a commercial product, and I am following a set of build instructions, please, again, no 'I would have done it this way' type posts. But if you are relatively inexperienced, and don't understand what I have done, then please ask, I don't mind explaining the why's and wherefor's. Plus I don't want to put anyone off from commenting, that is what posts are all about, but please try to keep them fairly short.

I expect this post to be linked to, and maybe become a 'running commentary' to the paper build instructions supplied with the kit. Hence I don't need it to be a long drawn out post. Except for my bits. :)

For the more experienced amongst you, I will be going thru the build showing how I do a few basic machining techniques, purely for people with lesser experience, so please excuse me if I show what you already know.

BTW, if you can build an engine that one of these are required on, I see no problems at all in you building one of these.

 :ddb: :ddb: :ddb: :ddb: :ddb: :ddb: :ddb: :ddb: :ddb: :ddb:


So let's get on with it.


The very first thing is to assemble the supplied laminations. 32 pieces in each stack, one LH, one RH. After I put them together, I tightened up the screws and stuck a mic across them, just to make sure my count wasn't out, I came up with the same figure for both.
The nuts were then slackened off slightly, and a small bead of superglue run across the flat back side of the lams, in two places on each stack, between the screws. The glue wicked easily in between the parts, so things were quickly tightened up, wiped off the excess, and put them to one side. They will be used later in the build.




Whenever I come to do a new project on my machines, the first thing I do every time is get the machine ready to do a good job. If the machine isn't prepared, then expect crappy results.
The first job was to have a good clean up of the machine followed by a lube of all points. I am lucky in that I have one shot lube on my mill, but it is an important factor in getting precision. Oil forms a layer barrier between the metal working parts, it is that, if it is not there or 'topped up' can easily give you error of a couple of thou, so at the start of each working day, lube up.

The next part is getting you machine to cut straight, flat and square.
I go thru this routine religiously, even though not required.
With a DTI in my chuck, and a thick parallel in the vice, I sweep across the fixed jaw side from one side of the jaw to the other. If you don't have a parallel like this, and your vice fixed jaw face is in good condition, you could swipe along that.




It should read the same all the way across, if not, adjust the vice position until it is. Mine was still spot on, mainly because I have a bar on the bottom of my vice that locates into the table slot, and keeps it that way all the time. I just did this to show you what is required.




Next comes one of the most important bits, tramming the head. You might not think this is necessary, but without getting it spot on, what you think is a nice flycut flat surface just isn't, it will have a concave dippy down in the middle.

I made my own tramming tool, so it was laid on the table and the two gauges set to zero. You will have to find a way of doing your own tramming exercise if you haven't made one of these yet.




Tool now mounted into the spindle collet and brought down until at least one gauge reads zero. As you can see, my tram is out, not by far, but it needs putting right.




Swivelling the head a tiny amount soon had it spot on again.




Only last week, I was having a discussion with Stew about how a lot of people can achieve a nice flat face on the job, but just can't get it square to a face ajoining it. This is how I get faces square to each other when starting off with raw materials. I get everything square first, then bring them down to size.

Mark each end of the rough cut bar as shown. If bringing round to square, you machine the first flat and call it number 1, then carry on the same routine as this.




Put #1 side up, and if possible the bar sitting on parallels. No need to tap it down, just resting on them and tighten up the vice




Then using you sharpest cutter, just clean up the face until all rounded corners are gone.




Before going any further with cutting, the bar is removed and deburred straight away and the vice given a good clean down.

The now cleaned up #1 face is now put against the fixed jaw and #2 face sitting at the top, and again only gently resting on paras. Between the moveable jaws and the job, you put in a piece of soft round bar to take up any irregularities. The bar in this shot could have been a little lower, say half way between the para top and the top of the jaw, that will give a more even pressure onto the #1 face against the fixed jaw.

The #2 face is then smoothed off, ensuring you end up with a nice sharp corner with #1 face.




After the cleanup and deburr, #1 goes against the fixed jaw, #2 goes down onto the paras and the soft bar is put into position and the vice tightened. Now you can tap the job down onto the paras. NOT belting it down, but a very gentle tap with a soft hammer. I use a lead hammer, but hold it by the head rather than the handle, that way I am not continually bouncing the job off the paras by hitting it too hard. If you are lucky, and have the first two faces square to each other, both paras should be gently trapped under the job.
This puts #3 at the top, and again that is flatted off.




For the last side, the soft bar is no longer needed. Because #'s 2 & 3 are parallel to each other and both square to #1, then #1 is tapped down onto the paras.
#4 is now skimmed down to give the correct dimension on the job.




If extreme care is taken, and at the end only tiny cuts, you can get rather close to perfect dimension, this is about 2/10ths of a thou out. Close enough for me.




Then it is just a matter of bringing the other pair down to dimension, in this case, spot on.




Now comes the little matter of getting the ends square to the other four faces. If you have an end mill that will cover the whole depth then you can just set the bar onto paras, with the end sticking out of the jaws and then just face it off.
In this case, I stood the bar on end with it overhanging the vice jaws. By shining a light onto the background, you can see how far out of square it is.




By gently tapping the correct way, you can get it sitting perfectly upright.
It looks like it isn't quite there at the bottom, but it is, what you are seeing is stray light shining on the corner of the block.
Make sure the vice is tightened up fairly well, but not enough to do damage to the part.




Then a very gentle skim over the top until all the rough sawcut marks are gone.




Nice and square.

All that is done now is the face just cut is sat down onto paras and the opposite end is brought down to final length.




Again, almost spot on.




This block took me nearly 1.5 hours to get cleaned up and down to size, but we are not in a production environment where time is money, so I don't worry about how much time it takes.

All I am interested in, is that when I come to machine this block up, because it is well finished, I won't have any troubles getting everything else to be in their correct positions.




So the next thing will be, hacking this lump down to about half it's weight.


Bogs
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Location - Crewe, Cheshire

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Offline madjackghengis

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Re: Building the Minimag
« Reply #7 on: February 01, 2011, 11:31:55 AM »
Hi John, very nice and thorough entry into the project, hitting all the important parts for an accurate build.  A very good start.  :beer: cheers, mad jack

Offline Bogstandard

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Re: Building the Minimag
« Reply #8 on: February 01, 2011, 01:18:19 PM »
Many thanks Jack,

I had an hour on it this morning, and because I had taken the time to get it as best I could, I had no troubles setting it up and getting some cutting done.

The way it has been designed, now I am getting into it, I reckon if you can get somewhere close, and get the other bits to fit, then the final truing up will put things right.

It doesn't need to be made as accurately as I have done, but as I am working to drawings with no tolerances shown, I am doing my best to keep to those sizes.


John
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Offline Bogstandard

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Re: Building the Minimag
« Reply #9 on: February 01, 2011, 06:36:34 PM »
A little bit more done today. It is time to start to cut bits out of the big ali lump.

Before I go into detail. Whenever I am cutting using a normal cutter, I very rarely attempt to do climb milling, sticking with conventional milling instead. My machine isn't geared up with the correct leadscrews to ensure it can be done safely, so I stay well clear of it normally.
There are plenty of descriptions about the difference between the two on the web, so if you are unsure about what I mean, then I would suggest you read and inwardly digest, to a point of where you think about it in your sleep. It could save your life one day.

On the build instructions, it says use the left hand top corner of the fixed jaw to set your basic 0,0 datum to. Unfortunately, I don't want to do that, purely because my vice doesn't support on the bottom of the job all the way to the outside of the jaw, on the KURT type, no problems on that score. So I will be moving my datum in towards the vice centre, and use my very rigid vice end stop as a substitute for the end of the jaw instead.

BTW, a few of the items I am showing have build posts for them on this site, vice back stop, tramming tool etc.




This is my setup, and it was an easy job with my edge finder to set up my datum corner.
I will just point out that the instructions do point to using a DRO for coordinate machining, but in my view, this magneto could easily be built plenty well enough by good layout and cutting to split the line.




In fact, even though I do have a DRO system, I still do a basic layout on a job such as this, purely as a double check as I am cutting.




Job mounted, pushed up to the backstop and gently tapped down onto paras, and the first cut on it's way.




On wide slots, or on any slot at all that needs to be accurate, I never use the correct width cutter to begin with. You will find that the cutter is usually flexed by the cutting forces involved, and will cut an oversized slot.

So in this case, a 16mm cutter run straight down the middle of where the slot is to be. It was taken down in stages until it was shy of full depth by 0.005". This is to allow a cleanup cut to be done at the very end.
Then I just gently crept sidewards to each marked line in turn.




As you get very close to the line, there are plenty of ways to measure to ensure you end up in the right place. On the finishing cut to the line, the tool was dropped to it's final depth and the cut was taken. The tool was then retracted up by 5 thou and the second line approached in the same manner.




Big slot in the right position, and to good size.




You then have to chew away at the two sides with the recommended 5/16" end mill. No problems in doing this, and it is at the same depth as the previous slot.
Except in my case, the marking fluid I used was washed away by the WD40 I use for cutting lube, and because my scribe lines were so feint, I overcut the length of the first slot by about 10 thou. But no problems, it isn't in a critical area and I just made the second one the same length, just to match it up.
None of us are perfect.




This is what you should end up with, minus ten thou on the rounded end.




The next bit is to lay a lamination against the slots just cut, and mark the 45 deg angled face onto the block. This is only a guide line, you fine tune as you cut it.




This bit had me perplexed for about thirty seconds.
The instructions suggest swivelling your vice by 45 degs either way to be able to machine to the lines. But as most people do, my swivelling base is languishing in the back of my shop somewhere, never to be seen again.

So I came up with this, a pair of V blocks, with both the blocks and the job being supported by the parallels. The cutter was already at the right depth, so it was just a matter of cutting the first one in the Y axis, and the second using the X axis.




Just like this, sneaking up on the angle so that the lam sits perfectly against all faces.




This is where the lamstacks will eventually be located. That is a job for next time.




A very boring day to follow. You will see.


Bogs
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Offline Ray

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Re: Building the Minimag
« Reply #10 on: February 01, 2011, 08:07:00 PM »
Bogs, this is a great build so far.  I appreciate you sharing your preparation with us. :thumbup:    Watching with a learning interest.  ironman (Ray)
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Offline Dean W

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Re: Building the Minimag
« Reply #11 on: February 01, 2011, 09:35:06 PM »
Good idea using the V-blocks, John.  Sometimes these solutions are sitting right in front of me, and I don't see it.
Again, good pics and descriptions.
Dean W.

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Offline raynerd

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Re: Building the Minimag
« Reply #12 on: February 02, 2011, 04:01:49 AM »
John, amazing first photos of squaring up the block. I learnt a hell of a lot!!

Chris
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Offline Bogstandard

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Re: Building the Minimag
« Reply #13 on: February 02, 2011, 04:29:34 AM »
Thanks you gents, and I am glad I am showing a few things that help people along their way.

I think I have found the right recipe of showing people how things are done. One or a couple of close up pics of the operation being done, plus a few words of text to explain it a little more. Well I hope I'm right, otherwise there will be a lot of confused people about the place.

I've just been having a think about the tooling that has been used so far, and I think most home shops have most of them. Three cutters, one pair of paras, a pair of V blocks and an assortment of cheapo Chinese micrometers, of which, after using them for a couple of years, I have come to trust as much as my very expensive counterparts, in fact in some situations, they are more accurate, as they have a vernier that reads to tenths. They could almost be classed as disposable precision tools for the amount I paid for them.

Just going out to the shop now, to see if I can get a little more done.


Bogs
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Offline NickG

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Re: Building the Minimag
« Reply #14 on: February 02, 2011, 11:04:21 AM »
Yeah thanks John, reading posts like this over the last few years are gradually teaching me how to do things properly in the workshop. I feel like I am either improving, or at least learning a new skill on every project I undertake now.

Nick
Location: County Durham (North East England)

Offline madjackghengis

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Re: Building the Minimag
« Reply #15 on: February 02, 2011, 11:35:36 AM »
Hi John, that was very nicely laid out, and well explained, beginning to end.  I really appreciated the innovative idea of the V-blocks, they were exactly what was needed, and far more accurate with no time lost, than trying to rotate the vise.  I'm keeping that idea for my next pass at a similar situation.  :beer: cheers, mad jack

Offline Bogstandard

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Re: Building the Minimag
« Reply #16 on: February 02, 2011, 05:47:19 PM »
I'm doing well today, no unexpected visitors calling to stop me getting to my machinery.

Today is mainly about holes, both little and large. I just hope it doesn't end up being a boring post :D

As I have been tapping and tinkering around the mill vice for a few days, on start up, I double checked that my 0,0 datum hadn't moved. No worries, it was still exactly where I left it.




On the very detailed build instructions, it says that you can either spot thru the lamstacks to mark their mounting positions, or use co-ordinated drilling. It is difficult for me to hold and hit at the same time and still keep it accurate, so I have opted for the electronic DRO route. I did a bit of measuring of one of the lams and got my first datum point, then I could just use all the drawing dimensions. This is my working out.




Using my figures, I spot drilled all the points, plus one in the middle, I will tell you about that in a couple of minutes.
You might notice that I said spot drill rather than centre drill. Ever since these drills have dropped in price dramatically, I haven't used centre drills since, they are just too inaccurate and very prone to breakage. For those in the UK, this is where I get them from. About the cheapest you will find anywhere.

http://www.engineeringsupplies.co.uk/drilling-c-160.html?9=172&10=&11=192&12=&13=




After spotting, I followed them up with a 2.5mm drill to a depth of 8mm, all except the odd one out.




Time for a bit of an assembly job.
You will find throughout this block machining exercise, you will add a bit more to allow you to machine a bit more.

So the holes were hand tapped out to 3mm and the bits were got ready to fit.
I would make a suggestion to do what I did, that is to clean down the lamstack holes, very gently, with a 3mm drill. Some of the glue had wicked it's way down to the hole area, and when I came to screw the screws back in, they were so tight, the lamstack started to split apart. So I stuck them up again, let 'em dry a bit, did the drill thingy and screwed them onto the block.

I had to add an extra lam to each side so that the brass lam sat flush with the surface. Spare lams are supplied for doing this very thing.




It looks like my drilling was OK.




At this stage the instructions suggest you mount the block into a 4 jaw on the lathe to do the boring. Unfortunately, that is very difficult for me to set up, and I find it much easier doing it on my mill. So you will have to imagine that what I am doing is on the lathe.

The spot drill point was refound by following the coordinates in the 'structions, and using a series of drills, I opened the hole up to the recommended 3/4". If you don't have drills of this sort of size, I would suggest you use the biggest you have, and bore the extra out.




Using my imperial boring head, the block was opened out to two distinct sizes, all very precise info is given in the build book, one all the way through, then the other to form a recess.




This is what it looks like.

The one all the way thru is to take the pair of bearings, and the recessed one for the rotor. You will notice that the boring operation has cleaned up the inside faces of the lamstacks.




So yet again, the block was put back to it's datum place.

This next stage takes you part way to fitting another bit, and also, why I wasn't worried when I overan the stack slot on the initial machining.

I am using a 5mm el cheapo Chinese end mill here, if it will do the job, why pay megabucks when you can get them for pennies.




Using the same technique as I used on the first large slot, a beginning slot was cut down to just shy of full depth, somewhere near the middle of where the slot needs to be.
I will be creeping towards the top area of the lams, and when I get there, put the cut to full depth and take a skimming cut across the top of the lams, just to clean them up.




Like this.




Now I needed to concentrate on getting the slot to a very snug fit around the lams in the coil. Measuring both sides up, they were the same size, but very slightly tapered back to front, larger at the front, perfect.

Get close, then using 1 thou cuts, gently open up the slot.




This is what I ended up with, the coil lams pushed fairly easily into the slot for the first 3/4 of the depth. When the holes are drilled and tapped, the screws will pull it in and form a perfect friction joint between coil and the two side lamstacks.

If they are too tight, a quickie swipe with a file will put it right, but that will be a bit later.



The coil bit has to be left now, while the cutouts in the block for the coil to fit into are done.

That is the next job.


Bogs
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Location - Crewe, Cheshire

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Offline Dean W

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Re: Building the Minimag
« Reply #17 on: February 02, 2011, 07:08:32 PM »
Quite an interesting thread, John.  It takes shape fairly quick after a certain point.
Dean W.

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Offline ozzie46

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Re: Building the Minimag
« Reply #18 on: February 02, 2011, 07:49:46 PM »


   Nice. Very well documented as usual John.

   Ron

Offline Bogstandard

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Re: Building the Minimag
« Reply #19 on: February 03, 2011, 01:26:15 AM »
Thanks Dean & Ron.

On first post of this topic I showed a line drawing of the part I am now making, which to a novice looked rather daunting. But as I have progressed, it is showing that with a few basic machining techniques, the complicated looking part is starting to emerge, one bit at a time, and that is how you should view all overwhealming looking parts. Just a series of easy machining bits put together, to make the whole.


John
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Offline Bogstandard

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Re: Building the Minimag
« Reply #20 on: February 03, 2011, 06:19:48 PM »
And now the final part about hacking this block into shape. Great cheers from the audience  :nrocks: :nrocks:

This block seems to have taken an age to get to this stage, but what you must remember, I am now a very slow machinist and builder, so most reasonably experienced people could do this whole block easily in a full working day, if you have things organised.

This stage is now to get the block into the correct shape to accept the coil, which is sitting on top. If you look very closely, you can just see the layout lines for the required cutout.




The usual thing, straight down the middle with a big cutter, not quite to the bottom of the required slot, then go to each side in turn.




Just reaching the second side.




And this is what it turned out like.




This next bit is the final shaping of the block. The level bit is done first, then the angle.




Because the lamstacks were not quite flush or below the side faces, I used an extra set of paras, one either side, but not as far forwards as the lams, So allowing the block to be held rigidly. The horizontal cut was then taken to depth and the correct distance in.




Again, because I don't have a swivel base on my vice, I can't do the cuts as shown in the instructions.
Because this angle isn't super critical to the build, I continued to hold the block as before, with 4 paras, but eyeballed the angle and made sure that the bottom corner of the block was resting on both lower parallels.




Using a 10mm ball nosed cutter I cut up to the line by about 2/3rds down from the top. Then once the line was reached, I continued cutting straight down until it was almost at the horizontal face. Once it was taken out of the vice, I blended the radius in to the horizontal face with a round file and a bit of emery cloth.




That is all the cutting that is needed.
As can be seen from this side shot, the coil can now fit where it should.




And another shot from the front.

The holes in the coil were then spotted thru so that the holding screw holes can be drilled and tapped.




Even though the block is to shape, lots of holes need to be drilled. Their positions are all shown on the plans.

These holes thru the 'ears' are for a couple of grub screws, that if you haven't got quite a tight fit of the coil lams to the side lams, the coil lams can be forced down so good contact between the two is made.

Because I am a belt and braces person, even though I have good contact between them, I am going to use these as well.




The next job was to pick up the two spotted marks and drill the holding bolt holes to depth.




These four 2mm tapped holes are for a cover plate to fit over the rotor. This is optional, but I think it is a necessity, purely to stop bits sticking to the magnets in the rotor.




Then finally, the four magneto mounting screw holes.




All the holes were tapped to their correct sizes, and the coil checked for fit.
This block isn't quite finished with yet. It needs some bits making on the lathe and fitting, then the few remaing holes can be drilled. But other than that, this is that very complicated looking bit finished, just by carrying out some relatively simple machining exercises.




Onto the lathe next time.



Bogs
« Last Edit: February 03, 2011, 06:21:46 PM by bogstandard »
If you don't try it, you will never know if you can do it.

Location - Crewe, Cheshire

Skype - bandit175

Offline Ray

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Re: Building the Minimag
« Reply #21 on: February 03, 2011, 08:45:07 PM »
Bravo Bogs  :thumbup:  :clap:
Ray
Waco, Texas

Offline madjackghengis

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Re: Building the Minimag
« Reply #22 on: February 03, 2011, 10:52:46 PM »
Hi John, very nicely done I must say.  I would take you for a former/present teacher from the way you lay this out.  You've provided some very needed info on the lams for a special project mag I have in mind.  Your set ups are very simple solutions to challenges which could easily leave some misalignment, and things not quite fitting exactly. :nrocks: very nice, mad jack

Offline NickG

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Re: Building the Minimag
« Reply #23 on: February 04, 2011, 04:56:11 AM »
John, nicely done. This block was very similar to making the poppin frame - when I first looked at it I was thinking of different ways to do it as I couldn't imagine me making it. But when I started and followed mostly the sequence described, the block emerged (as you said) as if by magic and I can now see the virtues of doing it that way.

I used most of the techniques you have but when I make my next frame I will use this post to make sure I do exactly as you did and make a better component.

Thanks.

Nick
Location: County Durham (North East England)

Offline Bogstandard

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Re: Building the Minimag
« Reply #24 on: February 04, 2011, 06:53:54 AM »
Thanks gents, the comments are much appreciated.

One thing you must remember though, the way I do things are my way, just to make things easier for myself, like boring, I have great difficulty setting up my four jaw on the lathe, so prefer to use my mill.

Nothing is written in stone, and there are usually many ways to obtain the same end results.

As the less knowledgeable amongst you gain experience, you will find your own little ways and shortcuts to get to where you want to end up. Whether they end up the same way as I do it, you will have to wait and see.

I was on my lathe this morning, and for me it is a lot more stressful than using the mill, so I had to give up early, so it may not be much of a post later.


John
If you don't try it, you will never know if you can do it.

Location - Crewe, Cheshire

Skype - bandit175