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Hi Folks,

I have a need for a bezel to fit onto a project that I am doing at the moment (new thread very soon).

The bezel, like so many, is circular with an 'L' shaped cross section.  The simplest way to do this is to use the metal spinning technique.

Pic ! - You hold the job on a former in the chuck of a lathe. Get it rotating then force a blunt tool (1/2" diameter Bull head brass rod) into the metal to push it where you want. 

This heats the area immediately under the tool and allows it to be deformed into the shape you want (usually).

Mild steel is easy to shape. I'm using stainless (grade unknown) and it is much more difficult.

The next 4 pics below show two attempts. The first attempt worked but on fitting onto the car it didn;t look complete.

The second attempt looked spot on for what I needed.

 

This is a very handy method of forming - but you do need a lathe and so brave pills.  

PS - this is not really recommended  on  a normal metal cutting lathe as it may wear the lead screw.

 

Roger

 

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Roger that looks really great

perhaps some custom H6 inlet trumpets ;) need to be tried. 

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Looks good Roger. Do you need to use high revs and is the wooden former pre-shaped to the desired profile? 

The lead-screw on my lathe is already worn but being flat belt-drive I think it would probably slip and stall the chuck.

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A couple of weeks ago I was thinking of making my own pancake air filters by spinning a lip on ally discs using the lathe faceplate as a former and just pushing it around the edge with a hand held metal bar.
I think 18SWG ally would spin quite easily.
I spent ages planning it and then decided it would probably be cheaper and a lot easier to buy them ready made.

Charlie

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The TRumpets would be relatively easy, depending on material.

A former is usually required otherwise the metal would TRy to bend where it should be flat and give big radii.

Charlie, you should have tried the spinning. The Ali plate would have turned over a treat.

If you had a simple ply former you could have done it by hand without the spinning.

All my jobs have a hole in the centre so that I can hold it in the chuck.  proper metal spinner use a spring rubber plate in the tail stock to hold the job./

The rubber squeezes the job against the head stock former.

 

Roger

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Roger,

I became intrigued, so I gave it a go, even though I have now bought ready made pancakes.
I didn’t realize how easy it would be. I had the sheet, just had to cut it to a square. Bolted it to my faceplate with a bit of flat bar to keep it pressed to the plate.  Cut it slightly bigger than the faceplate on the lathe and then pushed it 90 degrees around the edge of the faceplate.

First I tried a wooden bar to push it with.
Too soft, the ally just cut into the wood.
Then tried a mild steel rod.
Too hard, the bar started to wear the ally away.
Finally tried a copper tube.
Worked well.
(All a bit like Goldilocks…)

In all it took about half an hour from set-up to finish.

Not perfect, and would need a slightly bigger lip if I was going to use it, plus a final clean up, but surprisingly satisfying to do.

Charlie

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Hi Charlie,

Brass is the best material I found to spin Mild & SS. 

But you must have a lubricant between the tool and the work piece. Otherwise it will tear the work piece.

Now you will be spinning stuff left right and centre even if you don't want to.

This is a pic of my greatest TRiumph - surrey rear frame hole cover (item #9 Here  )

Roger

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1 hour ago, RogerH said:

Hi Charlie,

Brass is the best material I found to spin Mild & SS. 

But you must have a lubricant between the tool and the work piece. Otherwise it will tear the work piece.

Now you will be spinning stuff left right and centre even if you don't want to.

This is a pic of my greatest TRiumph - surrey rear frame hole cover (item #9 Here  )

Roger

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A pair of which custom made to fit the slightly smaller indents in the Honeybourne Surrey are gracing mine, thanks Roger they fit a treat.

Stuart.

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Also thanks to Roger. He was able to spin for me the twin bonnet catch spring cups.

I have spun aluminium hub caps for Messerschmitt KR200 in the passed, Spinning is a bit of a black art. I used hardwood pattern  blocks, with the tail stock of the lathe with hard rubber centre tight to the aluminium to be spun. After several attempts, the best method for me was to use a hardwood handheld tool tightly/securely  wrapped with cotton cloth, and a Bee's wax lubricant. The problem I found with aluminium was that if you are not very carful, you can pick up the aluminium surface, and end up with a record groove, something that you will not be able to simply polish out.

If you do have a lathe, have a go, you will be surprised just how metal moves around.

     Russell

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Hi Pete,

not sure what the correct speed is. It needs to highish as it needs to generate heat.

I think I'm on about 400rpm but higher may be better.

You must use a lubricant. I actually use Rocol Cutting lubricant.

I use a 1/2" diameter brass rod with a rounded bull nose.

 

I'm not really an expert on how to teach this mystic art. But it works for me.

 

roger

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Just get a machine like this:

 

 

Charlie

 

 

Edited by Charlie D
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A few years ago a job came into our factory in four very posh and expensive flight cases. Spun titanium hemispheres about a metre in diameter. Satellite fuel tanks. We were to electron beam weld them together and fit and machine a small connecting flange to each resulting sphere. How someone managed to "spin" these into shape is beyond me. The stuff just wants to return to it's original form when deformed. Lots of heat, I suspect, and lots of power!

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I've mentioned Hipwell before as the makers of hubcaps and headlight rims. Just found this video of the inside of the factory.

Birmingham at it's best !

 

 

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