Member postings for Bob Mc

Hi Ken..

now finished front panel apart from fitting Arduino and small pcb level shifter board... as below..

Above ^ the blue square is the lcd brightness control.

Due to the success of this DRO used on my lathe, I have decided to make another for the milling machine... so will chart my progress..

I must add that the calipers I used are the cheap ~8inch variety which seem to produce the right data format for the program I use, BUT... I can't say that the same format will be the same with any others ! ... I have used the program on four sets of calipers now and they work perfectly well.

The Level shifter circuit as previously mentioned..below..

In Block Diagram I showed a 'low volts psu' this can be dispensed with if the battery is kept in the calipers; In my original design I used a separate supply as per the block diagram but found that a small capacitor about 33uF was needed to cut down on noise pickup which affected the readings.

The Box.

As mentioned I used a double mains outlet socket ... I found the MK modern style variety to be quite smart as it has a slight slope on the front... no I don't work for MK ... the material the box is made of is some sort of plastic and mills quite easily but does produce some dust, ...Wear A Mask ... some of the ribs inside the blanking plate need to milled off ... see pics.

About to be milled.

After milling out.

Well let me know if you want any more information.

rgds..Bob.

They are obviously Scrummage Horn dePhlogistifiers..

Hi Ken...

the diagram below shows the main items and gives an overview of how they are connected up, I used an LCD with 'Serial' connection as this is a lot easier to wire up and program ... you can find them on ebay

One point I must address is that the dro unit gets all its instructions from the calipers and if the calipers are not adjusted within a few minutes then they switch off, consequently you can lose the position setting you had...but this is what happens normally with the calipers.

http://www.ebay.co.uk/itm/I2C-LCD-Display-1602-Blue-For-Arduino-Pic-Pi-/263112246526?hash=item3d42b644fe:g:cK0AAOSwvihY~Fh9

Will post the level shifter circuit next.

Overview diagram.. ...

Hi Ken...

I don't know about the Arc digital displays but it seems as if these products are made to be hack-use unfriendly on purpose..

As far as using an LCD display...yes certainly... a single axis reading should be easy enough, it is fairly straightforward to connect the calipers to wiring for the Arduino although if you wanted to have a remote reset to zero then the connection is more of a problem and probably best left alone... you can reset using the calipers button.

The main issues with connecting up to a remote display are ... setting up an LCD display...changing the voltage levels from the caliper to the Arduino...finding a program for the Arduino.. and fitting LCD and gubbins in a box, I use a 9v battery but make sure it's switched off when you finish..!

I will have to go and find the relevant information but will come back to you... in the meantime you will need to download the Arduino files to your pc.

It would help if you got a cheap Arduino Nano or any other Arduino to play about with.. these are available on ebay with the cable which connects your pc to it..

The voltage level changing I mentioned will require some soldering of two transistors and some resistors to a pcb... there are only 6 or so components so bear in mind that there is some hands on electronics required.

will be back....Bob...

I didn't need to make the grinding rest since I already had something very similar, but I did make the End Mill sharpening jig ... however I thought that the original design was over complicated and I dispensed with the bushes fitted to the MT2 collett holder and the bush for the probe rest... I also cheated by purchasing an MT2 collett holder with 1" straight sides, so all I needed to do was drill through the end to fit the collett securing screw.

You may also see that I did not make the locating fitting on the end as in the original, that also seemed a bit over complicated, so I just made a wheel with countersunk locating holes which an M6 screw fitted into, the end of the screw is turned to a slightly larger angle than the countersink giving a positive lock, this fitting is only used when grinding the end of the milling cutter.

When the collett holder is required to rotate as in sharpening the flute edges, the end wheel is taken off and and re-fitted 180 degrees back on the collett holder, a small step turned on the wheel for about 3mm stops the wheel from touching the M6 locating screw as mentioned previously.

Well...it works ok... Bob..

Hi All...

Ken Weeks said...

" I have a modified digital caliper fitted to my Myford tail stock.

The display on the caliper is difficult to read (eyes are not what they used to be) I would like to attach a remote display nothing fancy just to display the read out figures.

Any Ideas/suggestions? "

I made a simple DRO using an Arduino Nano and LCD display to show X&Y values from digital calipers, there is lots of information on the web available showing the Arduino programs although I couldn't find anything to show how to get 2 displays up at the same time so had to think about that one for a while....

Any reading can be reset to zero with the push buttons...the whole assembly is fitted in a 13Amp outlet socket and a blanking plate is used for the front panel..

rgds..Bob..

On the subject of 'can my pillar drill be improved' , I recently purchased a new pillar drill from a well known Mart which had a well known makers name on it... however I assume it was made in Asia somewhere.

I was expecting it to be of reasonable quality, it was certainly not cheap, my hopes were dashed when after putting it together I noticed that the quill could be shoved up & down some 1/4 of an inch without engaging the pinion rack gear, the control of the quill was not good and became a nuisance.... I complained to the supplier who did offer me some compensation but this was in the form of sending me their sales brochure...!

I was thinking of sending it back but the thought occurred to me that this sort of shoddy quality is what we customers are now obliged to put up with even if I exchanged it for another would it be any better...? I doubt it...

So I bit the bullet and started to think about how I could sort it out myself, I wish I had heard about the article: Re-engineering a low cost Chinese drill press, by Brian Smith as mentioned in an earlier post by OurBallie, it would probably have made it an easier job, but what wrangles me is that a book has to be written in order to put something in order in the first place.... it may be 'cheap Chinese' but in my opinion if it isn't fit for purpose then it shouldn't be for sale..!

Anyway rant over...! I decided to make eccentric bushes to take the pinion axle and therefore the pinion nearer to the rack, it wasn't an easy job, the thing had to be dismantled and two jigs made in order to bore out the pinion axle holes, then the two eccentrics made and some means of fixing them in place when positioned correctly.... the result...fantastic...!

Why is it that for the sake of a simple small change in the design which might incur some slight cost to the product, a profound increase in quality could be gained.....oh ***t ranting again...

better go.... Bob.

How much time did Michael G spend in giving information on finding links ? it must amount to 100,s of man hours, much of which has been interesting, useful and for many, including myself encouraging!

Come back Michael.... don't give up....you have many friends in this forum.

...Bob...

Thanks Ken...

I see what is happening now, nice job Ken..Thanks again, its great to be able to find information like this from

experts as yourself.

rgds..Bob...

Thanks Jason...

In MEW no. 246 page 17 there was an article about exhibits at Brooklands produced by MEW readers, one of which was a nice looking topslide made by Ken Wilson.

I was hoping for some more information about how Ken had managed to fit what is described as a "very compact toothed belt drive" to the leadscrew drive; was there...is there... any more information on how this has been done... I have searched the forum and not found anything, perhaps I am not looking in the right place.

In case Ken is reading this and there has been no previous discussion or article is there any chance of you giving me and others some more information.

Thanks in anticipation... rgds...Bob.

Hi Stewart..

Yes the flywheel is thick perspex as are the bearing housings, It was the only material in my junk box and I was concerned it would not be heavy enough but it runs ok and it was an education and a pleasure for me to make this model.

I think a heavier flywheel would be more appropriate ... one tip I can give is... bolt or clamp the engine base to a good solid bench, its probably my workmanship at fault, but when running it resembles a drunken Scotsman dancing over the crossed swords....! (not a derogatory remark to Scotsmen)... I am myself related to Scotland.

Thanks Stewart.

Knocked this together to repair me trains...

Yes..... I made one of those just to see if I could make anything that actually worked..!!

...nb... only ran it on compressed air but it certainly went.

My solution to a problem which has bugged me for some time...perhaps there is a simpler way...

I needed to turn down some threaded rod to fit a handle, the problem is that the dti needs a flat plate fitting to run over the threads so the rod can be centred in the four jaw chuck; a quick job in the lathe to make a flat plate fitting for the dti ... so I thought..!

But there was a problem, the dti has a step at the probe end so I couldn't just make a hole to fit the shank of the dti, after some head scratching I thought of a simple idea, but first see the stepped end of the probe.

I didn't know ... and still don't know, if the probe be unscrewed, but I was worried I might destroy it .. I wasn't going to try and force it.

So.... I rummaged about and came across an 8mm brass plumbing compression fitting... it was actually a coupler....would that be of any use? .... see below.

The picture is of an 8mm end stop which would also be suitable for the job.

I turned down some 8mm brass rod and bored it out to fit the diameter of the dti shank .... the part was then cut in two along its length, next I cut a slit in the olive so that the two parts would fit together in the olive, the cut in the olive made sure that when the accessory was assembled it was not going to be a permanent fixture on the dti..!

Next the end of the fitting is faced off, this forms the flat surface to ride over the threads of the rod.

The end part of the compression fitting with the internal thread is now placed over the shank of the dti and the two brass pieces are put over the dti shank with olive slid over them holding them on the shank.

The flat plate end is now screwed in place.

Below.... the two brass parts fitted in the olive.

The fitting in use.

It does slightly limit the travel of the dti probe but a couple of mm is more than adequate.

Hope it might be of use...Bob.

Re:- ignition coil ebay item ............0043

Hi Neil... looks like an inductive relaxation oscillator to me.

Bob.

Hi Bill,

I have used the same company as John Carruthers mentioned, VCSM in London, they cleaned and re-silvered two 6" mirrors for my binocular scope and for £10 carried out some optical testing.... Focault test..Knife shift..Focal length..Parabolic figures.. Surface irregularities...Astigmatism pinhole test... Cost in Dec 2015 was £104 for the pair...nb I have no connection with this company.

Thanks Clogs../ Ian..

Yes I do worry if there ever was an earthquake all my potted meat jars full of screws/drills/taps etc would be a miasma of glass and metal on the deck... honestly I am running out of room!! they never told me that the metal bashing hobby combines several others at the same time all requiring in-depth knowledge whilst you have to have pockets with a good depth as well..!

rgds..Bob..

Hi John ...

thanks for your appreciation.., yes you are correct, the handle is a Singer balance wheel .. I make use of these as they give good control and feel just right... I used them on my Atlas lathe and Dore Westbury miller... see pics

rgds..Bob...