Walkers BB reel - material used

[Shed_Monkey]

In the course of researching a new project I am reading as much as I can from a wide range of sources. While perusing http://dickwalker.co.uk/thewalkerreels.html I read with interest the recount of the machining chips catching fire while Walker turned the BB reel and having helpers rushing around fighting the fires while he worked.

The article suggests the material used to machine the spool was duralumin but there are some question marks around this. The proposed theory is that the flames were in fact the paraffin cutting fluid used while machining igniting. However, Walker annotated details of the reel in his copy of Be Quiet and Go A-Angling - changing the material listed from duralumin to magnesium.

Any schoolboy who has tinkered with magnesium will know how easily and brightly it burns - being the basis for flares which therefore makes me think it is likely that the reel is magnesium as the chips would easily catch fire as a result of the heat generated when turning as chips get very hot (I burned a lot of magnesium as a schoolboy!).

I believe there is also another clue later in the article where reference is made to Barry Grantham making replica reels which weighed in at 70g heavier than the original. Aluminium has a density of 2.7g/cm3 whereas magnesium has a density of 1.738g/cm3 which would therefore account for a significantly reduced weight in Walkers reel.

What do the members of the forum think of the evidence?

Cheers
Steve

[Lea Dweller]

I am not sure what the composition of the metal is that Dick Walker used to make “ Fredline’s” fabulous reel. Having held it, I do know that it is extremely light for it’s size. It would seem that only a “chemical analysis” would reveal what material the reel was made from, as in the absence of absolute written proof it would be the only way. I suspect that John (Fredline) would probably comment does it really matter?

[Crucian]

A magnesium alloy does seem likely. Interesting stuff to use, by the sound of it...

[Shed_Monkey]

does it really matter?

Only if you're a nerd like me

I found it interesting that he managed to produce a reel that was lighter for its size than expected - very clever.

I would have loved to have been a fly on the wall in the workshop watching flaming chips flying off the lathe - I suspect there would have been some "traditional" language used

[Wallys-Cast]

I may be totally wrong here but I am sure once read that magnesium is machined under water to prevent it burning. I haven't a clue how that is done by the way.

Wal.

[Watermole+]

I think this topic has already been considerably discussed at length by for what it's worth, my 2p worth..

When Richard Walker made those reels, he would have used whatever suitable material was to hand so you can probably guess what that was from where he worked. He almost certainly didn't buy it!

There is a lot of wild speculation about what happens when you cut magnesium alloys and 99% is just romantic notion embellished with the passing of time..
These alloys are in fact, quite easy and pleasant to machine, I know because I have bought and used them. They cut freely and leave a good finish if you use coolant. Far easier than Titanium for example, which is a dirty metal and an absolute nightmare in terms of tool life! Flaming chips of metal flying in all directions is pure fantasy. It just does not happen.
Duralumin has mostly been superseded by technology. It contained about 4% copper, which made it age harden, but the trade off was that it corroded quicker unless treated, but was tougher than the proverbial old boots.
The one essential when cutting magnesium based alloys is that the cutting edge of the tool is kept sharp. If the tool is allowed to blunt, then friction develops, thus generating heat.
If this state of affairs is allowed to continue, then sooner or later, flash point is reached and the hot paraffin vapour ignites...I have actually seen this happen to someone else when cutting steel. There is no explosion or conflagration, it just ignites and burns. Throw a blanket on it and it goes out.
Years ago, paraffin was used to lubricate lathe tools when cutting stainless steels and various alloys. It smells a bit but normally perfectly safe.

The problem with magnesium alloys is when you try and put the fire out. If you use water, or water based substances-and I am not sure of my chemistry here- oxygen is released, THEN you have a real fire on your hands!!!

If Richard was just using a HSS (High Speed Steel) tool which wore and became too blunt, then he might well have had a small fire in the bottom of the lathe but that was it. These things happen.

But, as has already been said, does it really matter what metal was used? When you are doing a "Government" job in the Firm's time, you use what is to hand. The important thing is that he made two reels of quite advanced and experimental thinking and that they have survived to this day and are in safe hands!

wm+

By the way Steve, if you want to buy any Mg alloys, I get mine from 'Aircraft Materials' company. If you want 6" diameter though, it comes from the U.S.A. and there is a minimum order + carriage charge.

[Shed_Monkey]

Thank you Leszek I am on a steep and interesting learning curve and enjoying the research.

The range of materials available for reel making and their properties is fascinating.

I have a lump of 4" 6082 which has a reel lurking somewhere inside - it just needs me to release it

Cheers
Steve

[Wallys-Cast]

Thanks for setting that straight Leszek and yes as you say Walker would probably have used what ever was at hand just as all guvvy jobs were made.

I only own a woodworking lathe so my turning ability is very limited to what can be achieved with chisels, gouges and a tool rest but metal engineering has always fascinated me and metal turning in particular.
I realise a good lathe is essential and things like milling attachments and driven tool holders are bonus features but it's the amount of different cutting tools, speeds and angle of cut required for differing metals that impresses me most and this can surely only be learned by years and years of experience.

Steve, I would love to see that lump of 6082 transformed into a reel or maybe that should read I would love to see the reel released from captivity. Please make a post about it.
Wal.

[Shed_Monkey]

Steve, I would love to see that lump of 6082 transformed into a reel or maybe that should read I would love to see the reel released from captivity. Please make a post about it.
Wal.

So would I Wal

As you rightly say, it takes a lot of experience to work metal - I have none What I lack in experience however I make up for by being stubborn and not letting a task beat me

It's going to be a long journey but if you are interested I will document the release of the reel when I get around to starting (some tool making going on currently) - Of course I may end up just documenting the creation of a lot of swarf

I would also like to thank Leszek and Evert for getting me fired up enough by their wonderful posts to get out and have a go myself

[Wallys-Cast]

Steve, I would love to see that lump of 6082 transformed into a reel or maybe that should read I would love to see the reel released from captivity. Please make a post about it.
Wal.

So would I Wal

As you rightly say, it takes a lot of experience to work metal - I have none What I lack in experience however I make up for by being stubborn and not letting a task beat me

It's going to be a long journey but if you are interested I will document the release of the reel when I get around to starting (some tool making going on currently) - Of course I may end up just documenting the creation of a lot of swarf

I would also like to thank Leszek and Evert for getting me fired up enough by their wonderful posts to get out and have a go myself

Swarf is good stuff too Steve, they make robots wigs out of it you know.

Wal.