Member postings for Dave S

Pretty sure pimoroni only manufacture electronics and laser cut plastic stuff.

There was no machining or anodising line there last time I visited.

Does the anodising dye have recommended current densities and times? Sound like the die is washing out of the anodised pores before they become hydrated.

Edited to add:

Is the dye water based? You could try boiling the part in dye rather than plain water if that’s the case.

Dave

Edited By Dave S on 08/09/2021 16:57:22

Busch burrs are made from HSS as far as I know.

Tungsten vanadium steel IS a high speed steel. The alloying with tungsten and vanadium promotes strong carbide forming tendencies, which remain hard at elevated temperatures.

Dave

**LINK**

Yes. The bridge over the belt does not need to be 1 piece, the slot can be formed by leaving a gap between 2 pieces.

atrach the plate over the belt of the belt sander - details left to the reader as it will depend on the actual sander. Make sure the gap belt to plate is small as possible.
the wedge hold the to be chamfered plate and you guide the plate through the slot until it stops cutting. DoC is limited by the jig - you can’t push the large flat bottom through the slot - a bit like how the cut on a wood plane is limited by its sole

Dave

46 grit and 60 grit would be a reasonable pair. If you want a polished finish grab a resin bonded diamond wheel.

Yes they are theoretically no good for HSS, but in practice mine is still sharpening HSS, Carbide and the odd bit of silver steel just fine after years of use (and the tools are also fine)

Why are you dipping HSS?

Hold the blank in a pair of mole grips and grind it.
You will not draw the temper - that’s why it’s called High Speed Steel. It has enough red hardness to cut metal…

Dave

If you look I’ve done the design, it just needs dimensioning…

The pins on the angle, in conjunction with the table over the belt set the max DoC.

make it from MDF -more than robust enough for your current run, and simple to work with hand tools.

The accuracy will be limited by the amount of care you take, but your making 1, and then the 64 will end up as matching.

Again I think are overthinking the problem

Dave

I’ve never had a problem with the 6” (ish -160mm) vice on my TOS.

Table is 10” wide

Dave

CAD vs Pencil My computer is off (typing on phone)

Literally a 5 second design sketch:

Jig is a simple work holding device that allows a quick, repeatable setup.

in this case it probably looks a lot like a block with a 45 degree face and a strap clamp.
Add a plate over the belt with a slot in it - think wood plane sole sort of thing.

poke jigged plate through slot into belt. Large block of jig lands on the plate repeatably.

all you have to do is make sure the jig sets up so the plates to be ground are in the same place each time - assuming the holes are at a known location 2 dowels in the face of the jig will do that.

I do not have that unit, and I would do this sort of thing in my chuffing enormous mill, with a different but similar function jig.

Dave

One of these: **LINK**

add a simple jig to hold the part at the correct angle, with a stop to prevent grinding too much off

edited to add: use the belt in horizontal mode, not the disk. 

Edited By Dave S on 03/09/2021 16:35:16

Neil,

Think there may be a typo in your email address?

Dave

Just remembered seeing this:

A rolling blog of everyday life on and around the workbench (shwoodwind.co.uk)

where Stephen uses an ER collet as a cutter.

Dave

In brass its a fair bet that for 12 an unhardened steel tool will last.

This:

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.

Dave

Not as a member, which I assume is what you mean.

Dave

Thanks, I hadn't thought to look at his marine clocks.

Dave

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.

Dave

Morning all,

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?

Dave

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

Dave

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. : )

Dave