Bending boiler band

[Robin GrahamParticipant @robingraham42208]

Hi. Nowt to do with model engineering I'm afraid, but Panto season is approaching (oh yes it is!) and I've been asked to make a hook for Cap'n Hook. Pic of work so far below (I hope). I want to make a leather cuff trapped beneath a band of brass which will all be secured by upholstery tacks.I've got a length of what was advertised as 'boiler band 22g' (but is actually about 0.9mm thick, so nearer 20g I think). Any advice on how to bend it smoothly without a rolling machine? The diameter of the wooden bit is about 100mm.

Thanks, Robin

[Robin GrahamParticipant @robingraham42208]

[Neil WyattModerator @neilwyatt]

Bend it round that lump of wood?

Seriously, I'd just clamp one end to a suitable former (something longer and not tapered, like a bit of drainpipe) and bend it by hand. Exact radius isn't critical, once you have a circle, it will be easy to close or open it up.

You could anneal it first, but that might actually make it more prone to getting an ugly kink in it, and you'll have to do a lot of cleaning and polishing.

Neil

[pgk pgkParticipant @pgkpgk17461]

That's an impressive weapon and nicely made.. but for a panto where the audience never gets close I'd have thought a bit of copper hammerite would have been expedient. Or recently I was playing with a slice though a fallen tree here – made a nice coffee table but did have one partial split. To fill that i mixed epoxy with gold coloured glitter powder (nail art on ebay) then sanded smooth. You could have turned a groove into that handpiece and done the same.

Whoever is wearing that steel hook needs to be careful. In danger of being a killjoy but I'd have gone with plastic.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by pgk pgk on 24/11/2014 22:05:48:

… I'd have thought a bit of copper hammerite would have been expedient.

.

If I read the opening post correctly; the band is functional, not decorative.

MichaelG.

Edited By Michael Gilligan on 24/11/2014 22:13:10

[Neil WyattModerator @neilwyatt]

So's the hook… are you sure it's not a production of 'Lost Boys'?

Neil

[Robin GrahamParticipant @robingraham42208]

Wow, thanks for the amazingly speedy responses.

Neil, I'll try what you suggest – was worried about getting kinks and whether better to anneal or not. I've got four foot of the band, so enough for two or three more goes if it doesn't work. first time.

pgk pgk – thanks, but as Michael says it is functional as well as decorative.Shall store the idea away though! I did think of plastic, but as the brief from the stage manager was to produce something more authentic so I modelled it on a real C18 prosthetic hook. He has complained that it's a bit too lethal though! I shall grind the point off .

Thanks again, Robin

[davebParticipant @daveb17630]

A friend had to have his index finger amputated at the first joint. I made him a smaller version of the hook. He was delighted with it and wore it when he went back to the hospital for a follow up visit.

Dave

[davebParticipant @daveb17630]

Sorry, I forgot, ARRRRRH!

Dave

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Robin Graham on 24/11/2014 22:51:50:

I've got four foot of the band, so enough for two or three more goes if it doesn't work. first time.

.

Robin,

Given that you have plenty of material … Wrap it round a smaller diameter [say 80mm] in a tight helix … then spring it open over the 100m+Fabric and trim to length. [obviously a slight twist is needed to bring it back to a circle]

MichaelG.

 

Edited By Michael Gilligan on 24/11/2014 23:24:28

[Boiler BriParticipant @boilerbri]

Oi! watch out you might take my eye out with that!

Bri

[pgk pgkParticipant @pgkpgk17461]

<<thanks, but as Michael says it is functional as well as decorative>>

Ah! (me hearties)..

In which case since you have trial spare I'd turn another timber rod, pre-drill the tack holes on a length and form the bend by tacking it around as you go.. perhaps for a better hold using screws unless you are prepared to use the upholstery tacks close together as in their furniture use. Once done remove, ease any springiness out of it and mount.

Have you considered the thickness of the leather? If your band is to cover the front edge then the wood could have been rabetted

[mechman48Participant @mechman48]

Watch out! I wouldn't of thought the 'elf n safety' bods will allow that 'weapon' in a public place, never mind what the director says…has a risk assessment taken place before that is worn… …?

George

[DustyParticipant @dusty]

Can I take issue with drilling tack holes and then bending. If you take that course you will find that the brass may bend across the tack holes, you will end up with a series of flats with a bend across the hole. Why? its the old story of the line of least resistance, because the brass is effectivley narrower at the point of the hole that is where it will bend.

[Neil WyattModerator @neilwyatt]

As Dusty says, I'd bend, then drill. Two strips of wood set about 2" apart on another bit of wood will make a 'v-block' to hold the prosthesis for drilling.

Neil

[pgk pgkParticipant @pgkpgk17461]

If fixing as you go then I'd have thought that the head of the last fixing supports it's hole and you would need a flat drift and light hammer for the next segment before fixing so predrilled holes shouldn't be an issue. Most difficult would be the theoretical need to tension the free end as you go round…..

[Robin GrahamParticipant @robingraham42208]

Thanks for futher advice since last thanks. I have read all, and shall inwardly digest. It is no doubt trivial, but I have had bad experiences trying to cold-work brass – I've always end up with kinks because of the work hardening thing. I'll give it a go tomorrow, bending undersize, springing it out and then drilling will be my first approach I think.

I haven't made a formal risk assessment on this job because between doing that and preparing the Gantt chart for project management I would hardly find time to actually do the work. I think I'll get away with it though!

Just for interest , below is a pic of a genuine? C18 prosthetic hook. What would the strap be attached to?

Regards, Robin.

[Ian S CParticipant @iansc]

The strap is attached to a shoulder harness.

Ian S C

[BazyleParticipant @bazyle]

I think the strap is attached to a band placed around the arm just above the elbow joint.

I'm not sure about this thicker material but thinner material loves to take on a bend when you are trying to flatten it eg by placing on a slightly resilliant surface like leather or layers of newspaper and rubbing or rolling along it with a larger diameter smooth rod.
It might work to push it round a mandrel with a round bar provided the bar is pressed very tight against the material and marndrel trapping it so that it is a continuous bend rather than a succession of straights and kinks. I think a bar would be better than a roller to keep friction/tension on the band.

[Martin CottrellParticipant @martincottrell21329]

Robin,

Why bother with the brass banding? Slide your leather sleeve over the wooden bit allowing it to protrude beyond the fixing area by 3-4". Then just nail around it securely with your upholstery tacks and fold the protruding section back over to form a realistic looking cuff that also hides the nails. If you require a more engineered solution substitute the nails for a nice big jubilee clip wanged up tight with a suitable screwdriver or spanner. "Wanging up" by the way is a West Country agricultural technical term describing the act of tightening something to a suitable level of strangulation without the need for torque wrench settings. The correct level of wang is usually signified by the satisfying pronouncement that "there, that b****r's going nowhere"!

Regards Martin

P.S I can't wait to see Captain Hook's sword and pistol if you're also making these!!

[Robin GrahamParticipant @robingraham42208]

Well, after all that I ended up doing it without the brass band. Thanks for all your suggestions though, which will be squirrelled away for future band-bending experiments. Despite Dusty's warning about creating weak points by pre-drilling the brass, I thought I might get away with it as the upholstery tacks need only 1.5mm clearance holes and the brass is 15mm wide by nigh 1mm thick. Plan was to glue the leather to the wood, start by tacking the brass down at hole 1 and work round. Alas, the crappy Screwfix tacks I'd bought were completely incapable of penetrating the wood (it was an offcut of hardwood which I had lying around, probably Bubinga) – they either bent or the shaft came through the head. So I would need to somehow bend the brass then drill pilot holes through. Avast I said to myself, avast! Enough is enough. And it hd to be finished by tonight. So I just drilled pilots through leather and wood and tacked. Unfortunately, though I'd calculated that pitching the tacks at 24 degrees would be about right aesthetically I haven't yet recommissioned my mill/dividing head, so had to resort to more primitive means. There could well be a one degree or more error in their positions! I'm just praying that no one in the audience notices and demands their money back, prompting a mass exodus. Anyhow, this is the result:

Martin, I liked your idea about folding over a cuff, but had already cut the leather when I read your post. I've not been asked to do the sword and pistol, but I did offer a C19 Cavalry Sabre which I have lying about. Strangely, my generous offer was refused.

Regards, Robin

[Neil WyattModerator @neilwyatt]

Perhaps the next September MEW should be published in pirate talk.

Contents:

• On the Capn's Table
• One Man and His Windlass
• A Cannon Ball Turning Tool
• Fitting a DRO to a Sextant
• Keelhauling on an ML7
• Sharpening Cutlasses on the Quorn
• Using CAD to produce More Accurate Treasure Maps
• Adept Lathe as Anchors

Aaarrrr!

Neil

[Robin GrahamParticipant @robingraham42208]

I'm almost tempted to renew my subscription Neil.

Robin

[pgk pgkParticipant @pgkpgk17461]

I've just got to ask if that's a right hand (or missing right hand) prosthesis: hook up or hook down? 'Cos doing it up would be easier with the laces inside………

… it looks a right handy bit o' work….

[Jeff DaymanParticipant @jeffdayman43397]

Hi Neil,

Re pirate themes for future articles-

You forgot to mention "pillaging the neighbour's workshop" and "keeping powder and shot dry in home workshops" or "how to reduce swarf buildup in deck swabs". Just some food for thought.

Yo ho ho, shiver me timbers, JD

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