What did you do today (2015)

[Les Jones 1Participant @lesjones1]

Hi John (Hinkley).
I would be interested to know which part of my suggestion on reversing the motor did not work. Did swapping over the wires to the brushes not work or was it the idea to use the 8 diodes to avoid having 4 wires coming out of the motor to the reversing switch. If it was swapping the brush connections over that did not work then it will probably be Keith Long's explanation of offset brushes. If swapping the brush connections worked but my suggestion of using the 8 diodes did not work then I will try to find a series wound motor to try the method myself and if it does not work then try to work out why it does not work.

Les.

[John HinkleyParticipant @johnhinkley26699]

Hello, Les,

It was the swapping of the brush wires that I tried. The motor didn't run at all after I swapped them around. I'm not sure if it was because of faulty wiring connections on my part or not. The wires were pretty short and very thin, to start with and by the time I'd got at them, were even shorter so, rather than completely nadger the motor, I put it back to the original spec and had a re-think.

John

[Bob RodgersonParticipant @bobrodgerson97362]

Today was a bit of a milestone for me.

I have finally managed to come up with a 3-D drawing and import it into my Cad programme where I was able to make a work piece,show my machine vice as a fixture in the correct position on the machine table, generate a waterline roughing machining, hole drilling machining, hole generating machining and a waterline finish machining Programme. The simulations show all to be OK with no clashes or gouges etc.

I have still to fine tune things like feeds and speeds but everything else seems to be good, including overhang of tools etc.

I have to admit that I completely lost patience with Turbo Cad and gave up on it after months of frustration. I am now using Iron Cad. I find it much easier to use than TurboCad and very intuitive. The Cam software I am using is Sprutcam 8, so far I have been very impressed with it, though the Translated Russian – English instruction manual sometimes has me scratching my head due to it's poor grammar.

Next phase will be to produce the G code, adjust the feeds and speeds to suit MDF cut a piece the same size as my workpiece and cut a practice part to see if all is good.

[Danny M2ZParticipant @dannym2z]

Yesterday I trimmed and soldered 4 wires to a pair of 12v electric chainsaw sharpeners for a mate (the cord had worn through at the body junction).

He was about to toss them as did not have a clue about soldering so he turned to me in desperation as he was advised to just purchase new ones ($125 ea) – Heatshink tubing amazed him btw (I used some to cushion the wires where they pass through the body aperature) .

I was a bit sad that such a simple job came my way but delighted with the result. has the basic skill of soldering an electical wire been lost to the masses?

After that we discussed the merits of a new type of .22 rimfire gauge that I made to measure variations in practical length of a .22 cartridge. Very interesting results at the range today.

* Danny M *

[Ian PParticipant @ianp]

Not actually done today (it was yesterday) is a 9 pin Lemo connector that I found quite a challenge.

The holes in the solder cups are 0.5mm diameter which is smaller than the seven dead straight strands of the wire cores so I had to open them up slightly with a dental burr. The cross section of the bundle of the eight wires cable is almost the same dimensions as the pins on the face of the connector.

The connector body where the pins are is 4.5mm diameter, the TO92 device is shown for scale.

I did four of these in several sessions over the coarse of a day as even with a magnifying desk lamp its quite a strain.

Ian P

[Michael GilliganParticipant @michaelgilligan61133]

I've just returned from an interesting demonstration of how to make a winding stem for a watch.

They concentrated on filing the square, and cutting the thread.

Having watched the Pro's do it, I had a go at the threading, and successfully die-cut a 1.2mm thread, 10mm long, on Silver Steel.

… A small achievement, but quite satisfying.

MichaelG.

[OuBallieParticipant @ouballie]

Ian,

How the heck did you manage to do the soldering?

I need to do something very similar, but am completely stumped as to the how.

Geoff – Having a of Ovaltine.

[Clive HartlandParticipant @clivehartland94829]

I work with LEMO plugs and sockets all the time and the best way is the crimp type.When having to recover damaged Lemos I do solder and if the wire diameter is too much for the solder bucket in the pin then trim off a few strands. Yes, it is fiddly work.I also solder in situ with the pins in place using a very fine point soldering tip. I also ensure that the cable is cut and trimmed by measurement to ensure nothing gets stretched when assembles. Users seem to very rough with them and not realize they have a lock/slide release and try and pull them out. Another damage is treading on the Lemo as it trails on the floor. They are expensive and need great care to not get them dirty in mud and the like. Do you have the special spanners for tightening up the Lemo?

Clive

[Ian PParticipant @ianp]

Clive

The 9 pin version of the OB connector is only available with solder buckets, the data sheet shows they have 0.45mm holes so cutting off wire strands (which I never do) wont really help as even only two strands side by side hardly fit in that hole diameter. Biggest problem with this cable is that the 4 twisted pair wires are in a different sequence to the pin layout and are also a loose fit in the cable jacket so the collet does not grip well.

I made a very thin wall metal sleeve that I slid between the wires and the outer jacket so the collet had something solid to close down on. I was able to organise the wires into the right sequence before they pass through the sleeve and then pushed a short length of thicker wire in the middle of the bundle to force them into a circular pattern trapped inside the sleeve.

I dont have the a genuine Lemo spanner so I made a thin 8mm AF one for the purpose.

You are right about the vulnerability to abuse. fortunately the audio/video users seem to be used to working with delicate equipment.

Geoff

What is it you need to solder? maybe I can offer some advice?

Ian P

[Clive HartlandParticipant @clivehartland94829]

Some years ago while at Leica i worked on the setting up and monitoring system for BAC who were making a Satellite. I cannot remember which one but it was a big one with lots of reflectors that needed precise alignment using 5 Theodolites all connected through a couple of MUX's. Lasers were involved as well for targeting all powered by separate Psu's.

The number of LEMOS i made up and the cable numbers was legend, some of the Lemos were like 25 pin and all soldered. Lots of smaller one too.

All connectors to LEICA Surveying kit is LEMO, FGA. 1B and the like. We hold stock as the turn over is quite high.

Clive

[Ian PParticipant @ianp]

I was involved in a similar but different Lemo legend story.

I made a mixing console for a PA rig (for Demis RIP) which we fitted with large (about 50mm OD) push-pull Lemos, the type with the 'stepped' male and female contacts that had about 50 contacts. The mating face of the cable and the chassis mounted connectors were identical. The multicore cable which was about 3/4" diameter had 15 sets of individually screened twisted pairs.

I volunteered to wire up the first end of one cable. There was not a lot of room between the collet and the solder points and each screen had to be sleeved and connected to its own pin so it was quite laborious. I then created the list of wire colours-v-pin numbers.

My colleague then attempted to fit the Lemo to the other end of the cable but it initially looked impossible! What we had both not thought about was the orientation of the cores through the cable are a mirror image of the opposite end, whereas the Lemos were not!

We (mainly he) eventually managed to fit the connectors having to manage the umpteen wire crossovers in the same space that I had found challenging when wiring the first end.

Ian P

[WindyParticipant @windy30762]

Yesterday I did a test firing of the flash steamer at the new club workshop it was an interesting morning.

Had repaired the generator tubing then modified the engine slipper piston similar to a F1 design.

Will strip the engine later to see how the piston performed when I modified the original piston to a slipper I was worried about crankcase lubrication being discharged through the uniflow exhaust as results were to show I did not need to worry.

Paul

[Anonymous]

Lemo connectors, that takes me back. In the distant past when I worked at Pi Research all the race car harnesses were made with Lemo connectors. Rumour had it that Pi was the biggest customer of Lemo UK. Agreed that they are a PITA to assemble, especially when you got up to 20+ contacts. I normally left it to the wiremen. Hands were rubbed when a car crashed as it inevitably meant a new harness, needed yesterday, for which a premium was charged.

Andrew

[Michael GilliganParticipant @michaelgilligan61133]

… Acquired yet another restoration project:

An early model Drummond Round Bed lathe

the type with bolt-on Bronze Bearings.

Serial Mark: MCHA 2452

MichaelG.

.

Advice from the wise would be greatly appreciated.

[Keith LongParticipant @keithlong89920]

Michael

My first bit of advice would be to join the Yahoo Drummond lathes group. Very friendly and helpful bunch of folk and a lot of info on Drummond lathes available in the group files.

The second bit of advice is that when you come to do any machining on the round bed you think through what you want to do and don't just blindly follow what would be done on a more conventional lathe, as the swivelling cross slide can be both a blessing and a curse if you get the machining ops in the wrong order, guess how I know – I've got 5 of 'em!!

Good luck with your machine they can be a great source of fun.

Keith

[Michael GilliganParticipant @michaelgilligan61133]

Thanks, Keith

MichaelG.

[John HinkleyParticipant @johnhinkley26699]

For those of you who have expressed an interest in the construction of my toolpost spindle and our visitors having returned to the UK, I've been out in the workshop again. To save cluttering up this thread with pictures not everybody wants to see, I've updated the album. More metal-munching this pm as the ride-on mower has a puncture, so an excellent excuse not to mow while I wait for a new inner tube to arrive!

John H

[pgk pgkParticipant @pgkpgk17461]

Some days you wish you hadn't started a job <sigh>.

Lovely weather, signs of spring hitting Wales so i thought I ought to service all the garden/farm stuff that's been hibernating with just a monthyl start-up over winter.

First up was the push mower. Battled it to start after cleaning the plug and a drop of petrol in the cylinder and warmed it up. A large oil pan under the body and pull the drain plug. Oil spillt out, flowed around the top of the deck.. and ran over the high side! I cleaned up the mess. Re filled. Next was the generator which I found has a flat tyre. Pulled to a steep bit of slope..warmed it up, pulled the drain plug.. actually caught all the oil this time and transferred it from the pan to a large labelled bottle. Refilled with oil and tripped over the bottle of old oil. I cleaned up the mess.

Next was the rotorvator.. which went more or less OK. Then the ride-on mower..which has a punture! Then I notice I;ve labelled the oil bottle 'Waist oil' – what a pratt! Sod it, i thought. I fueled up the quad bike to take the dog for a run… it has a flat tyre…

I decided to leave the wood chipper, both chainsaws, two strimmers, hedge cutter and leaf blower for another day….

[Gordon WParticipant @gordonw]

pjk- re- flat tyres. Get yourself some puncture preventer gloop. The stuff that looks like washing-up liquid with bits of ground -up rubber in it, use it in all my small tyres including trailer.Not had a flat in 4 years, there's tempting fate! Can't remember the name, a bottle will do about 6 little tyres, when I can afford more will do the tractor.

[martin perman 1Participant @martinperman1]

Gordon, PJK,

There is anther way depending on the sizes required, I recently had a puncture on my electric buggy and when I checked the other tyres decided to buy four, a search on the internet found tyres with infill with a rubber compound which means they dont need air and hold there shape so no more punctures, you do need split rims to fit them though.

Martin P

[pgk pgkParticipant @pgkpgk17461]

I've actually got the 'goop' just these tyres haven't needed it yet. But if memory serves it's better for tubeless and if used in tubes can stop patches sticking.. and it all depends on how big the holes are.. The quad bike has had one tyre gooped before as has the ride-on mower – for some reason tubeless tyres with tubes – but this is thorny ground and fixing it was a non starter with the hedgehog of thorns through the outer – so tube pulled and tubeless valve fitted.. which I'll likely have to buy for the current quad bike tyre. Just really annoying to find three on the same day.

[MuzzerParticipant @muzzer]

John H – nice work. Coming together nicely!

I'm a bit puzzled about how you change speeds. It looks as if the ratio change gear cluster doesn't fully disengage from the first gear before it starts engaging with the second gear (if you follow me). Doesn't that make it impossible to change over unless the output gear is in the correct angular position relative to the input gear? It may just be the perspective of the photos.

Murray

[John HinkleyParticipant @johnhinkley26699]

Muzzer,

I agree. It does rather look like that. The output gear pair and change cluster were machined as separate gear pairs. When brazing the change cluster together and Loctiting and pinning the output pair, I ensured, as far as possible, that the teeth were aligned such that sliding the change cluster meshed directly with the output pair, if you catch my drift.  It seems to work with a little wriggle room to play with.

John H.

Edited By John Hinkley on 18/03/2015 20:46:24

[pgk pgkParticipant @pgkpgk17461]

Definately not my day today.. mechanical failure and crashed one of my r/c helis and the alternator belt failed on my nissan when driving to the village..managed to limp home without cooking the engine..

I've got a bottle of Appletons rum that's been waiting for an excuse to be opened…

[MuzzerParticipant @muzzer]

"managed to limp home without cooking the engine.."

Does the alternator belt actually drive the fan? How old is your Nissan? Didn't know here were still belt driven fans on the roads….

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