1/2 round beading

[ppplant]

In a previous post, I enquired about the availability of 1/2 round brass to finish off the top edge of my Garrett tender, and I was very quickly pointed towards LSM as a supplier. So far, so good. However, it has occurred to me that brass,(a) may be difficult to paint, and (b) may need polishing, instead. I do not relate very well to Brasso and am wondering if there is a equivalent profile available in steel? This would take paint more readily and be more authentic, as I have never been on a full size engine where the tender is edged with brass.Does any one know if 1/2 round steel is out there, and, if so, where from, please?

[havoc]

Why not make it yourself? Wrap wire around a mandrel, fix ends and turn away half of it.

[jasonb]

Can you remind me what scale the engine is so I have an idea of the width. I will be using steel on my fowler but that is more of a rounded flat than a full half circle.

Edward George in his traction engine book shows a method of tack welding rod to a bit of scrap steel flat, the bar is then milled to the required section before grinding off the welds. They are often not a full half round so you probably want a 1" radius but 3/4" wide.

Havoc, I think it will be difficult to wrap 3/4"+ dia bar around a mandrel

Jason

EDIT, I see its a 4"

[jasonb]

20x10mm half round any good www.fhbrundle.com/sect-04.htm

Jason

[havoc]

Well, I'm used to think in gauge 1 sizes. Sorry. However I once met a guy how wrapped 50mm steel bar around a mandrel to create a huge clothespin. Took some time, manpower and heavy machinery but it can be done.

[welshy]

I had a similar problem on the top rails on the tender of my loco, it has 3 half round rails running around the top for coal rails. I ordered some half round brass but found it was too soft to stand up to the job it would bend too easily.
The sections I needed were only 5/32". I ended up milling down round section steel rod by clamping it directly to the milling machine table and working on about 4 or 5 inches at a time and moving it along to the next section by using packing pieces the same thickness as the half round cut section the rod stayed straight as i went along. I ended up with the 3 correct sections each approx 4 feet long and was very happy with the result, You can see the rails in the photos of the Stirling on my previous posts.
Hope this helps
Mike.
PS I wouldn't like to try and straighten the beading after coiling and and turning it as suggested

[steam4ian]

G'day all

Maybe it's my steel industry experience but I do wonder why nobody has suggested making a set of rolls. Annealed brass rod could be rolled down to half round. You would have to work out appropriate roll profiles for each pass but it is not imposssible.

Regards
Ian

[jasonb]

Brass is readily available so why roll it. The OP specifically wants steel which is more prototypical and holds the paint better.

Jason

[durhambuilder]

This may work:
www.tauntonme.org.uk/oilyrag/may09/notesfromnorthmay09.html

[jgb7573]

A neat idea there. I like the drive mechanism!

[ppplant]

Thats a good idea, but I need about 5 feet of beading, 5/8 wide by 1/4 thick. I estimate that to get this size section, I will need to machine it from1" or 11/4" round bar, making for a lot of waste. As I can get brass in the right dimensions, I think I will probably end up using that. Before I paint it, I will lightly go over it with the sand blaster and just take off the smooth surface, leaving something for the paint to key to.With an etching primer, I hope this will be ok.

[phil1001]

I used to build in 4mm and used brass a lot for bodys etc.. Although I never had the heat problems you could get with live steam, I always used to flat back the brass with fine emery or garnet paper then give the bodys a good wash with a scouring powder and rinse down with fresh water. Dry off with an old hairdryer or use the airing cupboard and then when fully dry degrease it with lighter fuel or acetone (if you can still get it!) just before using an etching primer. Flat down the primer with 600 grade or more when dry and degrease again before putting the colour coats on will give a pretty good paint finish on brass.

Phil.

[Myford Matt]

Phil - any decent chemist will order you acetone. They will probably ask you 'why?' I simply said 'model engineering' and they were happy with my answer.

[jasonb]

You can also get it from any fibreglass suppliers.

Jason

[simonwass]

Try a local fibreglass company, they use it for washing resin from tools, they might give you a jamjar full, its all you'll need for degreasing.
Chemists have isopropyl which is as good as a degreaser although as its medicinal grade its very expensive - £5 for 1/2 litre, I can buy a gallon for that!

[phil1001]

Many thanks for the heads up about Acetone Guys. Living in Norfolk I forgot about all the boatbuilders around here - DOH!!. Looks like I'll have to visit a freindly one and show him my empty can!.

Phil.

[ppplant]

phil1001 thanks for that, its another way to go. My wife has a 500mil container of acetone, she uses it as nail varnish remover. I will raid her dressing table in due course.

[jackrae]

PP
if your wifes nail varnish remover is of the cosmetic variety it will contain some form of oil so will be useless as a surface cleaner.
remember the good old days before the junkies when you could buy benzene, and carbon tet and goodness know what other solvents over the counter by the demijohn.
OK maybe they are hazardous to health but we're all going to go sometime.
jack

[ppplant]

Jackrae,thanks for that. I have just read the label on madams acetone bottle, it is not pure, contains an oily additive, just as you said.Will check for local boat buiders.