Member postings for Mark Rand

We still do, although PVC window frames and double/insulated glazing tend to be used with silicone rubbers.

I never realized that there was a word for the stuff that coolant dams are made with. I've got a couple of fairly significant plasticine ones on the surface grinder table. Some idiot (me) didn't get it properly leveled when grouting it into place. That'll be fixed if/when I get around to rebuilding it..

Or Isopropyl alcohol AKA propan-2-ol

I would caution that the BCA collets don't grip as well as some other systems. There's a very strong chance of a carbide endmill pulling out of the collet.

I've been wondering about making a BCA side lock holder for FC3 disposable cutters. They have the advantage that they can't pull out due to being retained by a grub screw in the Weldon/sidelock slot in the cutter. They're also available in carbide.

The windings will be on the inside of the laminated stator, which is probably pressed into the outer casing. So long as you stay away from where the wires go from the junction box to the end of the stator you should be fine.

I actually had to weld up a crack in the casing of the feed motor of my lathe. The cast iron casing had been split when the end bells were pressed into it.

Right:- update time.

I discovered that my only 12mm open ended spanner has got slightly sprung jaws. Doesn't normally affect it, since my normal reaction to a 12mm AF nut is to replace it with something else.

A 12mm hex (not bi-hex) socket fitted the outer, accessible nuts quite well.

A Bahco 4" adjustable spanner was thin enough to get to the inner, less accessible nuts.

The engraver produces far straighter lines once the play in the two joints is taken up. It isn't prefect yet, but it's better than it was.

I worked as a petrol pump attendant from 1970 to 1976 (that's age 12 to 18). 22 1/2 hours per week on the 18:30-22:30 shift on some school days, 12:30-22:00 on saturdays and 07:30-12:20 on sundays. We weren't all that busy and I could do my homework easily in between punters. Used to get a £1 bonus if we sold £100 of petrol. That only tended to happen in summer (off the A38 in devon, halfway between exeter and plymouth).

Deity knows what the do gooders would say nowadays.

Edited By Mark Rand on 13/03/2022 19:30:21

Rubbing alcohol is 70% isopropanol, Surgical spirit is ethanol denatured with methanol and castor oil, methylated spirit is ethanol nenatured with methanol, pyridine and a blue dye, IMS or Industrial methylated spirits is ethanol denatured with methanol.

When getting spirit to keep your glass insulin syringes in, make sure that the chemist doesn't dispense surgical spirit. It really buggers up the syringes and makes the pistons sticky.

All of them can be used to fire the Mamod steam engine, but the stuff from the NHS was best, 'cos it was free.

Edit to add that I wish the gauge 0 steam railway at the various model engineering exhibitions used IMS instead of mythylated spirit. The Pyridine stench from the meths that they use is vile.

Edited By Mark Rand on 13/03/2022 14:54:42

It isn't a Whitworth size, or a 12mm metric size, or a BA size.

Mr Micrometer says its 0.467" AF.

An update on this topic. I've spent the last few days making a new rotor for my V block. It seems to have succeded.

I glued (with Loctite 648) and screwed two surface ground lumps of steel to a milled block of aluminium. Mounted the assembly with a Myford dividing head on the milling machine and roughed off the corners. The reason for using an MT2 drill chuck rather than the three jaw lathe chuck was that the lathe chuck fouled the milling chuck.

This is what the innards look like. It wasn't an intentional dissassembly, I got it a bit warm when turning is on the lathe with a chipped insert and the glue came apart. But it does show the general arrangement.

This is the finish turned rotor.

I match marked the ends with one dot at one end and two at the other to simplify reassembly

After cooking it in the oven to release the Loctire, I cleaned it up and reassembled the bits. This took some care, the 30x30x15mm magnets are extremely strong and want to sit on top of each other, not side-by-side. I actually used the bit of wood, clamped with two, distanced, G cramps to sit over the first magnet while pushing the second magnet into its pocket. The edges of the steel pole pieces are also razor sharp and need respect. More Loctite 648 was used as glue.

At this point I learned that it would have been better to use a taper reamer in the screw holes before separating the parts, so that they could be accurately realigned with a couple of taper pins. I had to turn a couple of thou off the assembled rotor to get it to fit in the V block. Not a nice thing to do with a strong magnetic assembly.

After getting it all together I gave it a little test. It happily holds up a 27kg electromagnetic chuck. With the original magnets, I could pull the V block off with my hands.

Edited By Mark Rand on 13/03/2022 12:45:52

Last time I saw the prices in Lynn, it was 3/6 per gallon. That was a few years ago though...

12mm is a very sloppy fit, even though it's the closest that I had.

My mind had been working along those lines as an option. Possibly with the surface grinder or an endmill.

Hey, after I get the engraver working I gan grind off the original markings and engrave some new ones.

Yesterday I decided to try and get the Taylor & Hobson Model C engraver going that's been sitting in the shed for 10-15 years. I made new drive belts from round PU belting and tried it out. There is slack in some of the pantograph linkages, although it looks like vertical play rather than radial play is the major culprit. As it happens the linkages involved are adjustable, But:-

They seem to have nuts that are 15/32" AF. This isn't a size that I've come across before and doesn't seem to match any series that I can find reference to.

I can use my smallest adjustable spanner and could mill a pair of fitting spanners out of gauge plate, then harden them, but I'm curious as to if anyone has ever come across this size?

And we (insulin dependent diabolics) lost our 7.5 class more than 20 years ago.

Old or not, the ring mains will be designed for and fused at 30A.

I must admit that I bought a Mitutoyo vernier height gauge second hand from Myfords about 25 years back. It hasn't needed a battery yet. Hasn't even got a space for one.

One could always use a 15A round pin plug and sockets. .

I wouldn't be worried about the Lidl plasma cutter's EMI emmisions, Any plasma cutter will produce a fair amount of EMI, and a fair number of us probably have far more highly rated ones.

I get them from CPC/Farnell along with lithium AA, AAA and alkaline C and D cells.

Indigo Rose have an interesting smokey flavour until they are too ripe.

San Marzano is a good plum tomato with a a nice flavour for use as a salad tromato as well as a cooker.

Both are non-Ft types. and the seed keeps for a long time if you keep it bone dry after fermentation.

Sweet Million F1 is a good sweet cherry tom, but prone to splitting at the slightest provovation.

Sweet Success F1 is a good Sweet cherry tom with a thicker skin.

1) Adjust the handle nuts so there is some drag on the screws and the feed screw nuts so the backlash is minimal. This reduces any tendancy for the slide to move under vibration.

2) If 1 isn't sufficient, then nip up one of the gib screws when you need to lock the slide, you shouldn't need this though.

I don't think that you'll find a cheap source of Walker Twinset seals, probably better to just bite the bullet and pay the money.

It's a shame that Hardinge/kellenberger have trashed the J&S organisation.

Edited By Mark Rand on 07/03/2022 19:33:11