Here is a list of all the postings Dave S has made in our forums. Click on a thread name to jump to the thread.
|Thread: Is there such a thing as an 'external reamer'?|
Just remembered seeing this:
where Stephen uses an ER collet as a cutter.
In brass its a fair bet that for 12 an unhardened steel tool will last.
was made to produce a stem tube and crown guards in brass:
Its much smaller, but its not really any different in process. Given the tool is still silver coloured I almost certainly didn't heat treat it.
Make the hole the correct depth and it wont overfeed.
I would bore a suitable hole in a piece of steel bar, ensuring it was the correct depth, then just use a hacksaw /files to gash the teeth. Being brass no rake is required. As its a spigot on a flat plane, rather than the tube feature I was making there shouldn't be a tendency for the chips to pack up - they can just fall off.
To use turn the spigot to correct length and a small amount oversize in diameter, then run tool in in the tailstock.
|Thread: Harrison Remontoire info|
Not as a member, which I assume is what you mean.
Thanks, I hadn't thought to look at his marine clocks.
|Thread: Ruggedising a Type 17 Stepper motor electrical connection|
The 'quick and dirty' way I have often employed is to turn the motor so the wires are at the bottom, secure to the motor body with a cable tie and 'pot' the whole connector and tie in hot melt glue.
|Thread: Harrison Remontoire info|
I was recently given a copy of Decoding Harrison - which is a series of essays about the Burgess Clock B - based on Harrisons designs.
There is mention of having a remontoire but details of the actual design are lacking.
Anyone have a good primer on remontoires in general and the Harrison one in particular?
|Thread: Dividing this would have been an interesting exercise !!|
They have to be parallel and equally spaced.
The divider gives me a set of circles, the 1/16" scribe ensures I don't make a gross error.
The (assumed) milling machine /jig bore table takes care of the parallelism - drill one side then move in Y to the other side and drill. Move a precise 1/16 in X, set up over the scribed circle, drill the next one, move in Y.
Repeat until done.
That's how I would do it.
The item is a diffraction grating, used for looking at spectrums of stars I think
Edited to add: the circular pin layout is purely aesthetic, and it isnt that old -1920 - that it would preclude the use of an accurate leadscrew driven xy machine
Edited By Dave S on 15/08/2021 10:05:15
16 lines per inch, there are at most 72 wires.
Think they are 1/16" apart - sounds like rule and dividers layout. : )
|Thread: Society of Ornamental Turners - contact details|
I thought there should be a page like that.
Anyone here for contact details for the Society of Ornamental Turners?
There doesn’t seem to be a generic “Contact us” on their webpage.
|Thread: Dipping a toe in TIG - what do I need (apart from skill)?|
A foot pedal is on my list to organise, but it’s not super useful when lying on the floor…
I was going to look at a torch mounted slider but I’ve not got round to it yet
I use a ck17 sized torch for my TIG. I got the actual CK one with super flex cable on it and it’s way nicer to use because of that - heavy or inflexible cable is a pain- TIG is supposed to be the sensitive welding process after all.. The torch is 150 amp rated (100% duty) - duty cycle is something to watch on a cheap torch.
I use purple E3 electrodes now (previously red and grey for dc and ac respectively) They seem good all rounders, but I haven’t experimented with lots of different types.
Oxy experience is useful, but on a TIG you can’t just pull the torch away to reduce the heat. Took me a long time to relearn that reflex…
Getting comfortable and supported in welding position is important. I was welding upside down under a car at the weekend - MIg would have probably been easier, but we use what we have. Getting well positioned for those shenanigans is even more important.
An autodark helmet is a good idea. Especially with a scratch start - one less thing to think about.
Clean material is a must. Not just a quick wire brush, but proper clean and shiny. With OA you can getaway with suboptimal prep, not so much with TIG - fit up, clean, supported positioning etc - all make a huge difference.
|Thread: Help with surface plates in Derby|
I bought these from Amazon (hope the link isn’t against the rules)
They work fine with my Stuart’s blue.
For a machine build recently I did a bit of scraping - It avoided a couple of rather dubious setups on a surface grinder, as my mill is large enough to rough out the areas in 1 setup.
Before I did that I did a little practice piece, on a gash 2" x7" wood plane. This is the end result:
I only had to knock a few thou off the plane, and I was only trying to get flat, not flat and in alignment to something else.
I have a new granite plate which I used as the reference.
The biggest thing that helped with consistency was buying an ink roller to spread the blue out. Before that I was using a wadded up cotton pad, which was very hard to get consistent blue spreading. I also ended up lookng like a smurf a lot...
For a scraper I used a chunk of power hacksaw blade clamped to a handle made from a wooden file handle and some scrapbinium:
Scraping is very relaxing, although physical work - it has a natural rhythm and work proceeds at a leisurely pace. I think the plane took about 4 or 5 evenings of an hour or two, but I wasnt rushing and I was learning as I went. The machine build needed a couple of weeks of evenings IIRC, bu then I did manage to mill it a bit wonky, so had to correct the geometry a bit as I went, as well as making the 2 dovetails fit together.
There are a few more photos in the planar plane album.
How bad are the surfaces of the plates you want to sort out? The odd pit wont matter to much - as long as there are not loads of them.
Editied to add: I have a mill that is large enough to face off your plates in a single setup (TOS FNK-25) Im based in Castle Donington if that helps. They wont be meterology flat, but they will be close and clean.
Edited By Dave S on 03/08/2021 18:24:11
|Thread: Anyone know what this is|
Suspect it's a combo drill/ mill bit for PCB manufacturing.
|Thread: Stainless Watch case|
Will edit later at home - and pull the photos locally.
They all show for me - but then if they didn't I would have noticed...
I originally planned to make the case and stem tube in one piece, but the rather large hole required a new plan.
I filed 4 'teeth' onto it.
The original crown and stem fit beautifully, Feels like the o-ring seals will be fine.
Of course its somewhat fiddly to get at the crown with it totally surrounded by a guard.
Flip and repeat for the other side
Ta Da! now its simpler to get to
The milling has left somewhat sharp lines on the guard.
I wanted to blend them, so with the help of a hot glue gun and a piece of carbide I made a radius filing jig.
My little assistant helps to illustrate the size of these things
Crown sorted now time to do the light pusher.
Then made a quite long, stepped and very thin thing. To turn this on the lathe would have been 'tricky', especially as the stock is already hardened.
All the bits are made - time for some finishing. I surface ground the straight edges, of course scrapbinium is not magnetic, so I had to make a fixture to hold the case to the chuck. First I ground the sides and then I added some facets - to reduce the weighty look of what is admittedly a large is chunk of metal.
The end result came out ok I think.
Couple of years ago Daughter picked up a cheap 'dive inspired' quartz watch. Not a bad thing, and for a couple of quid it was reasonably priced given it didn't appear to work.
I started by bunging a bar of recently acquired stainless scrapbinium in the lathe and set to. (Anvil for Scale )
The stick out was a bit much, so I set up the steady in avoidance of wearing a 2" diameter chunk of steel
Faced the bar off to give me an idea of what I was working with,
and then chucked a hole at the middle - the movement is actually a lozenge shape, so I roughed out the movement hole and the step for the crystal and chapter ring.
That done I bevelled the front and parted off a roughly case sized ring.
The hacking out of the movement hole will come later - on the Milling machine.
Seems I didn't take any photos of the initial lug cutting, but now the round is more of a case blank shape
The movement actually sits pressed up against the back of the chapter ring, so my datum point was the recess that the chapter ring sits in. The back of the blank is not yet at a specific place, so I made a brass plug to sit on the chapter ring ledge and allow me to set up from the other side
These 2 mini slots define the ends of the lozengeish movement shape.
There followed a lot of strange angle milling - which I apparently took no photos of - but that's not too surprising as I had to concentrate a lot...
Then the movement fits!
You can see the odd shape in the plastic case here.
Next up was to work out where the stem and light pusher holes needed to be, and what size.
What you can't see in this picture is the snapped carbide drill bit inside the nearly completed hole
These things happen, but I was a little 'upset' about it.
Fortunately I've picked up a few machinists rescue methods...
This is a single lip cutter - its ground out of a solid carbide bar and is a fair amount bigger that the hole I intended to make, but needs must - I can always sleeve it (shh - spoilers
I machined the round surface flat first, so I had a good starting point, and then pecking 1 thousandth of an inch at a time I proceeded to drill out the broken bit and the rest of the hole. Incidentally the plaster is in no way related to the watch case.
Now seemed like a good time to make it more watch case shaped, so I created some angled sides - Straight edges and curves are IMO a good design statement.
Whilst I had the case setup I put in the spring bar holes - I prefer drilled lugs as it makes strap changing much easier.
Part 2 to follow as the post is too long
|Thread: Help with surface plates in Derby|
Eley metrology can probably recondition your plates, but I bet it is more cost effective to buy a new granite one.
My 4’x2’6” table has a planed finish. It’s flat (for some values of flatness - workshop grade and well out of certification. .
|Thread: Lathe protection|
If your storing it get some boeshield on the machined surfaces.
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