By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Forum House Ad Zone

Bending boiler band

All Topics | Latest Posts

Search for:  in Thread Title in  
Robin Graham24/11/2014 21:49:46
1089 forum posts
345 photos

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

bandbendingq.jpg

Neil Wyatt24/11/2014 21:55:14
avatar
19226 forum posts
749 photos
86 articles

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 pgk24/11/2014 22:05:48
2661 forum posts
294 photos

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 Gilligan24/11/2014 22:12:45
avatar
23121 forum posts
1360 photos
Posted by pgk pgk on 24/11/2014 22:05:48:

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

.

no

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 Wyatt24/11/2014 22:22:17
avatar
19226 forum posts
749 photos
86 articles

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

Neil

Robin Graham24/11/2014 22:51:50
1089 forum posts
345 photos

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 angry.

Thanks again, Robin

daveb24/11/2014 23:16:04
631 forum posts
14 photos

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

daveb24/11/2014 23:17:05
631 forum posts
14 photos

Sorry, I forgot, ARRRRRH!

Dave

Michael Gilligan24/11/2014 23:22:32
avatar
23121 forum posts
1360 photos
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 Bri25/11/2014 07:03:14
avatar
856 forum posts
212 photos

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

Bri

pgk pgk25/11/2014 07:34:24
2661 forum posts
294 photos

<<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

mechman4825/11/2014 09:11:04
avatar
2947 forum posts
468 photos

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... face 22 ...?

George

Dusty25/11/2014 09:22:11
498 forum posts
9 photos

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 Wyatt25/11/2014 09:28:26
avatar
19226 forum posts
749 photos
86 articles

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 pgk25/11/2014 10:10:52
2661 forum posts
294 photos

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 Graham26/11/2014 00:28:19
1089 forum posts
345 photos

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.

hook.jpg

Ian S C26/11/2014 10:15:52
avatar
7468 forum posts
230 photos

The strap is attached to a shoulder harness.

Ian S C

Bazyle26/11/2014 13:57:58
avatar
6956 forum posts
229 photos

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 Cottrell26/11/2014 20:43:11
297 forum posts
18 photos

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 Graham27/11/2014 20:52:42
1089 forum posts
345 photos

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:

hookwithleather.jpg

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

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Sign up to our Newsletter

Sign up to our newsletter and get a free digital issue.

You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy

Latest Forum Posts
Support Our Partners
cowells
Sarik
MERIDIENNE EXHIBITIONS LTD
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest

 

Donate

donate