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Member postings for Dave Halford

Here is a list of all the postings Dave Halford has made in our forums. Click on a thread name to jump to the thread.

Thread: First Locomotive
24/12/2021 23:58:20

They have a boiler that leaks like a sieve from joints and another one that leaks from all the fittings and yet another that tests OK for nearly 3 grand but thin gauge and "the fire box has taken a set". Whatever that means

Andy,

Buy which one floats your boat - AND which one you can get still castings and drawings for but be prepared for trouble.

Thread: Blank Tee Nuts.
24/12/2021 15:48:20
Posted by KWIL on 24/12/2021 12:11:01:
Posted by Dave S on 24/12/2021 10:57:30:

They don’t need to be t shaped.

I would just get some hot rolled bar of appropriate width and lop a chunk off.

Dave

Beware of this approach, you have less metal in contact with slot underside and run the risk of damaging the slots. More inclined to tilt as well.

That would be true if m6 thread nuts are used in m8 thread size slots, Bosun is trying to avoid that.

Thread: Testing Medieval Gunpowder
22/12/2021 19:09:36
Posted by Mick B1 on 22/12/2021 14:16:34:

Posted by SillyOldDuffer on 22/12/2021 11:26:06:

...

'Caponier' rather than 'Capuchin' I think.

On the subject of dense acrid smoke, I'm just finishing Vol 2 of Kuropatkin's 'The Russian Army and the Japanese War'.

The Russo-Japanese of 1904/1905 is interesting because it was the first modern war: steam transport, barbed wire, concrete, telecommunications, high explosives, QF artillery, machine guns, balloons and much other scientific nastiness.

Both sides used smokeless powder.

...

Dave

'Smokeless' is a bit of a relative term, like 'stainless' for steel.

Look at any photo or footage of a large 20th C warship firing its main armament, and there are always vast volumes of dense, dark smoke emitted - even though 'smokeless'propellants like nitrocellulose, cordite or their analogues were in use. In some notable sea battles, such as Falkland Islands in 1914 or the final Bismarck action in 1941, ships had to alter course in order to prevent their own gunsmoke clouding their gunnery direction.

I've never been able to find out why such copious smoke was emitted by heavy guns, when smallarms really do produce very little. One witness to the Gallipoli bombardments in WW1 blamed the silk bags in which the propellants were loaded to the guns. I even begged a bit of silk from my wife's weaving stock, and loaded it into a couple of .303 rifle cartridges to see if I got a puff of smoke when I fired them at the next range meeting, but got nowt. Anyway, the German guns, which had used big brass cases like oversized rifle rounds, smoked just as badly as the British.

Some have suggested that it's steel particles from the gun chambers and bores, washed out by the high pressures and temperatures. But the rifled liners for the big naval guns lasted about 300 - 400 rounds - say a third as many as an infantry rifle barrel at the time - so if that were so, the rifles should have still smoked a fair bit more than they did.

Battleship main guns used 6 x 100lb bags of nitro cellulose propellant LINK the link is interesting

Thread: warco 16 b advice
19/12/2021 18:23:33

there's stuff on U tube

Thread: Lathe tool set
19/12/2021 11:51:16

The beauty of a set can be that all the inserts have to same tool height except the boring bar.

You do have to be very careful which set you get, there's one UK supplier that only sells replacement inserts as sets so you have to buy 6 you don't want to get the one you need and thats £30 for the 7 tips. Whats worse is they have no idea what the tips are.

Personally I tried a cheapy 12mm CCMT 09 set of 4, left ,right, straight and boring bar from the PRC, the 10 pack of tips supplied work but were a bit iffy. The holders are fine, excluding the bar they all have the same centre height so no need to mess with repacking. I also have a JB DCMT tool for times when you need something more pointy.

Used with HSS feeds and speeds alloy CCGT are best for finish on steel even en3 comes out well, just dont take big cuts on steel or the tip will chip.

Thread: Pin-hole in oil pan - which product to patch it?
18/12/2021 15:20:35

If it's not too modern there should be a drain plug, otherwise the whole pan is the drain plug and things get much harder.

If you know where the hole is and you can get a set of ramps under the appropriate wheels to clear the pin hole of oil.

Sand the rust off as best you can and use resin core solder. It's possible to tin steel immediately under the iron tip with a 40w iron by rubbing it fairly hard. Small rust pits and the hole can be bridged with extra solder or a small piece of brass.

I would not insert any foreign body into the pan, if a screw punctures the filter or glue gets in there and sets you may need a box rebuild. Also brazing may distort it and give you a leak at the gasket.

Failing all that Petro patch (the fuel tank one) still exists.

Edited By Dave Halford on 18/12/2021 15:23:23

Thread: Flexispeed main bearings lubrication and drill arbor
18/12/2021 10:48:00

Some tapers are made to the correct taper but different diameters so you can get more or less stick out. I would look for secondhand ones. If a drill chuck wobbles on freshly faced round stock the centres may be offset

MT SIZE D1 (MM) D2 (MM) L2 (MM) TAPER (ΜM/MM)
0 9.045 6.401 50.8 52.051
Thread: Firing a 1" Minnie
16/12/2021 10:43:01
Posted by noel shelley on 16/12/2021 10:21:41:

A 12v car heater blower can sometimes be adapted, provided the fan or impellor is not plastic, or if compressed air is available then an extended chimney with a small bore pipe let into the side pointing up will act as a blower. The idea is to PULL the fire up not blow it from below. Such a small coal fire will require constant attention. Noel.

Which is how Ady's little would actually work, though I'm sure Paul will already have worked that out.

15/12/2021 16:16:00

The smaller you get the bigger the pain they are.

The Minnie boiler mounted water pump probably won't work when it gets hot.

Small air leaks around the smokebox have a big effect, as does the blast nozzle location,

Sometimes they work on air but won't work on steam. If it's not been fired before it sounds like a steam test was not undertaken so don't trust the safeties when you do fire it.

Thread: Vee belt question, for Centec 2B
14/12/2021 23:02:15
Posted by Howard Lewis on 14/12/2021 16:04:42:

better to run withb the idler on the back of the belt.

1 It runs on a flat surface

2 The angle of wrap around the pulleys is greater,and tends to press the belt into the groove, rather than out of it, Meaning that, in extremis, more power can be transmitted.

Howard

Sometimes, Fenner belts used to have the name moulded with raised letters on the outside of the belt.

Thread: Warco digital readout broken
13/12/2021 19:44:50

Remove an end plate, slide the head out and use a tissue and alcohol to clean the glass.

Did you check that the led lights?

Thread: Hello from Bromsgrove
13/12/2021 11:39:00

This one from Screwfix also appears in Lidl under the Parkside name for less. Either way the vice needs looking at.

Thread: Gentlemen a problem for you to answer
13/12/2021 11:16:14

I had a car rottisery mounted on four 1" plain plummer blocks, don't use ball races and make the buffer beam connector arm adjustable and a drilled circular disc to take a tent peg size locking pin.

Thread: Which graduating tool?
09/12/2021 15:04:10

It's only the price of castings against bar stock.

Thread: Head or quill feed when slotting
08/12/2021 19:36:46
Posted by Mike Donnerstag on 08/12/2021 17:26:05:

My question is, should I lock the quill and use the head feed (Z-feed) and the three axis DRO that I fitted, or should I lock the head and use the quill feed? Which is best?

I tried the former (locking the quill and using the Z-feed) and the mill started to shake. Is this due to movement on the pillar dovetail? I had more success with the quill feed, milling the slot in about 0.5mm increments.

Many thanks in advance,

Mike

Yes, this might imply that your head feed dovetail is looser than you thought it was.

Thread: Etch Primer life
08/12/2021 16:10:22
Posted by Bob Unitt 1 on 08/12/2021 14:33:05:
Posted by Robert Atkinson 2 on 08/12/2021 12:31:49:

Any 2 part paint is unlikely to keep for very long once mixed. Putting in the fridge will help. Some 2 part materials can be frozen once mixed to stop them curing. This is used for some ircraft sealants.

The Phoenix website says 3 hour pot life. Closing the lid will make no difference to this.

Robert G8RPI.

I thought that time-limit was just for spraying ? I know the 1-part primer is good for a month before it loses the ability to etch, and was wondering if the 2-part is just the components of the 1-part in a form which will last longer until mixed ?

Edited By Bob Unitt 1 on 08/12/2021 14:36:38

Bob,

Think of it as a car body filler, once you add the oxidizer hardener the result is only altered by temperature.

1-part is ordinary acrylic paint and dries mostly by solvent evaporation.

2-part requires the hardener to be added to effect 'drying' and based on isocyanates it's very nasty to breathe.

The etch action is an entirely separate to the drying process

Thread: Getting started with carbide insert tooling
01/12/2021 19:57:00

I use CCGT09T304, which are meant to be used for ally on steel, using HSS speeds and feeds.

Push the feed and the tip will go.

Stall it in the job and the tip will go.

So they will all chip equally well if you are clumsy with them

They are no more nor less robust than any other size turning tool unless you include milling cutters which are much tougher. The 04 is the tip radius and means semi finishing, as in gives a decent finish but not as strong as an 08 rougher

Thread: Letterboxes
01/12/2021 19:19:15

Lockable box outside and the old slot filled with a brass door finger push pad either side.

Thread: Workshop disposal
28/11/2021 19:20:06

A middle road might be to ebay the lathe and the other large items with their matching tooling.

So the lathe gets all the chucks cutters, holders, steadies etc, so someone new has all the gear to start. Same if there's a mill or even a pillar drill. Use the photos to 'list' whats included.

There's not that many big items sold like this any more and newcomers are more likely to pay a premium if it's all included.

Try to sell any random stuff to those who turn up

Thread: 80mm ARC Versatile or 73mm Precision 3?
27/11/2021 19:00:36
Posted by Bill Phinn on 27/11/2021 14:39:50:

Can someone summarise the pro's and cons to a layman on the clamping types between the precision 2 and 3, rack/hex key vs screw and handle?

I have a type 2 and a type 3.

Not an exhaustive list, but things that come to mind:

Type 2 pros: rapid jaw opening/closing over big distances, minimal jaw lift.

Type 2 cons: engagement of cam in locking notches sometimes a faff requiring adjustment of locking screw. Not getting this right can result in part not being properly secured and/or end of locking screw making contact with worktable. Surfaces on which work and parallels sit is a little on the narrow side for the size of vice.

Type 3 pros: probably firmer hold on parts is possible and there is a broader base to seat parts and parallels on.

Type 3 cons: marginally greater tendency for moveable jaw to lift. Opening and closing across big distances slightly more time consuming.

 

I would add

type2 con no base tenon slot for a swift set up to parallel with the table

type3 pro has a base tenon slot for a swift set up to parallel with the table.

 

I have an 80mm Accu lock vice (same as the versatile) and confess I have used the swivel base once.

Edited By Dave Halford on 27/11/2021 19:02:29

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