Member postings for not done it yet

Local model engineering societies are a suggestion as would horological groups as well?

Faversham looks promising?

Could any of this be done on a lathe or milling machine ?

It could all have been done on a milling machine. Including the holes.

What is the required precision of this part? Like, would clearance holes be adequate?

If you have a mill (and neither rotary table nor dro), someone could easily obtain the coordinates for the holes from their own dro. Altenatively, using self-help, finding the coordinatesfor those holes is a fairly straight-forward operation.

Part off with the lathe - or is the spindle bore too small?

Your location is likely rather remote (as in ‘not local&rsquo to most on here. If it was a little more precise, someone local may have been able to cut them for you.

Even a ‘saws-all’ type machine would do it, I expect?

Got a mill? No real problem, if you have.

How about removing tailstock, crank carriage to far end of bed and replace tailstock in front of carriage? If it will fit, that is.

The problem, with such welding, arises when you come to reversing the part between centres for further machining.

Better, IMO, to fabricate a drive dog than mess around as you have done. A piece of flat bar, a bolt and nut as a drive and a pinch bolt (a slot cut to allow some pinch) or grub screw to affix the drive dog to the part being machined. Maybe spot drill the workpiece for the grub screw?

What power is your motor for your chop ‘grinder’?  350mm discs will need a fair amount of power.  Also be aware of disc speed limitations - you will need different speeds for different diameter discs

Edited By not done it yet on 18/06/2023 08:53:41

I am needing to form what can best described as a large washer out of 3mm mild steel late.. 39mm dia centre hole, with a 89mm outer edge.

I am suspecting that ‘(p)late’ is actually 5mm, not 3mm? I’m certainly hoping it is not two unattached pieces measuring a total of 6mm! That could be positively dangerous!

If two pieces, please securely fix them together before machining.

Drilling/boring and affixing to an arbor might well allow clearance over the cross slide, if those corners were sawn off or removed with an angle grinder.

NSU Quickly.

I only know of two mopeds with a 2 speed gearbox. Quickly and Mercette. My Mercette used a 4 stroke OHV engine.

NSU Quickly.

Personally speaking I would not rely on the Morse taper without a draw bar especially when interrupted cuts are envisioned such as typical when fly cutting.

Hence my post, re providing a clearance hole for use a drawbar for the 2MT.

Agreed, Rob. Well that should be the case but I don’t know the force provided by the wider spacing type. I think the area in contact with the chuck is really the defining requirement.

A more economic option might be to use two mag chucks - thin stuff is unlikely to be 18” long! Further, care is needed when clamping larger, but thinner items, if one requires more than just a very smooth surface finish. Thin items are generally only a problem when small in contact surface area.

I am extremely careful when grinding small items (yes, I have needed a ‘bullet arrestor!).

Another thing I don’t like, about the suggested item, is that it doesn’t appear to have provision for side/end support.

I would likely have purchased a fine pole chuck but am using what I have. I doubt I would be paying that little money for a decent quality chuck, however. But the choice is up to the poster, not me. I will add that I’m most certainly not a fan of cheap chinese tooling.

I have an adaptor but the flats that engage with the tang of the Morse taper interfer with the drawbar.

Why not simply bore out the adaptor to 3/8” clearance? End of problem?

Measure and work out the pitch to see if that is what they indicate?

From the net:

“What are the different types of thread gauges?

Thread gages can be one of any number of types of gages. These in clued plug, ring, 3-wire, micrometer, tri-roll comparator, measuring wire, screw thread insert (STI), and thread gaging roll thread gages.

What type are yours?”

The use of such words as ‘suction’ and ‘disc’ do not give me a great deal of confidence re the description.

I have a couple of Eclipse chucks, which do the job for me. Not fine pole but these have been around for years and still work

As well as whether tailstock support was used. Guessing it was as it should have been.

Not important, but did you check for taper? It looks like that finishing cut was of too little depth for the cutter?

Back in my motorcycling days, I only came across the CB160, CD175, CB72 and CB77 and CB450 with cam chains. I can’t remember any chain problems with those roller chains. I recall that the crank sprocket on the CB450 had fewer teeth (only 17?) than advised in engineering circles. That worked OK for Honda, even though it drove two cams.

There were engines (back in the 1930/40s) that had a cotton-waste filled oil filter that could clog up the large area of the oil pump intake. Mine still has that cotton-waste filter, but clearly not used much these days. Also, I think a contortionist would be able to clean the screen without major engine dismantling (via the crank inspection covers).

I’ve no real experience of high speed chain drives over multiple sprockets. Slow speed systems seem to works OK. Chains just around a couple of sprockets seem to work OK - and at very high engine speeds. I’ve not heard complaints of motorcycle cam drives, particularly.

The Peugeot 2 1/4 DOHC diesel engines utilise a dry toothed cam belt to one cam and the second cam is chain driven from the first. We had a belt failure but the chains do not seem to fail. Go figure.

As I see it, chain drives are noisier than belts, but I expect duplex chains would be too heavy and too expensive for long runs. The A series engines (mini, minor, etc) are often fitted with duplex chains to avoid chain-wear problems.

Simply having a small gauze plate as a coarse filter (before the oil pump) looks, to me, to be a disaster waiting to happen. Historically, that coarse filter was of far greater surface area. I believe there is a high power (audi, bmw, merc?) engine which can suffer from a tiny fine gauze screen embedded deep in the engine! If it is not checked/cleaned on higher mileage engines it can cause expensive repair bills.

Computer designed engines can sometimes get things wrong…

Perhaps change from hob-nailed boots to, say, plimsols? Potentially less pressure exerted on the ‘loud pedal’ accelerator?🙂🙂

Maybe change your footwear, John? ‘Eco’ may be more related to the economy of materials in manufacture? Or related to the economy compared to the non-boosted engine? Almost certainly marketing hype, whatever it means.

My proxy said, you probably won't get away with micron accurate work but it's certainly good enough for many years of use. He's had is running and is positive about it in general.

As soon as read that, I thought - who the h*ll expects to work to anywhere near that precision on a manual lathe.

I reckon to the nearest 10 microns is good - even very good - and good enough for most things turned on a lathe.

Anyone comment?

Check out:

THIS

While I use my little hand-held bender for vehicle brake pipes, my CZ has several formers for bending pipes. A very useful tool to pick up if you see one offered second hand.