Making a metal cap for a wooden post
Tim Downie
consist of a domed metal cap on a 4"x4" post.
I had originally though of making the cap of lead but a quick google suggest
that lead "burning" is well beyond my skills & equipment levels so I
wondered if either I can work the lead "panel beater style" to cover the top
and extend down the sides for a few inches or whether I should consider a
different metal like an aluminium alloy.
Of course I could just contract the work out to someone to do properly but
I'd like to have a go myself.
Any suggestions?
Tim
Tim Lamb
<timdow...@yahoo.co.uk> writes
You could go with the BT solution to telegraph pole tops and use an
inverted V.
regards
--
Tim Lamb
pcb1962
> I've an idea to create a memorial post for a departed friend which would
> consist of a domed metal cap on a 4"x4" post.
>
> I had originally though of making the cap of lead but a quick google suggest
> that lead "burning" is well beyond my skills & equipment levels so I
> wondered if either I can work the lead "panel beater style" to cover the top
> and extend down the sides for a few inches or whether I should consider a
> different metal like an aluminium alloy.
Copper would be fairly easy, as long as you have a suitable wooden
former. Wickes sell round balls for the top of newel posts that would
be ideal, £9 IIRC). You'd need to anneal the copper a few times so a
blowtorch would be handy. Any model engineering supplier can sell you
a suitable piece of copper.
Dave Osborne
Copper? You could solder/braze it.
Me Here
"Tim Downie" <timdow...@yahoo.co.uk> wrote in message
news:i0ir90$l6g$1...@news.eternal-september.org...
http://www.hooverfence.com/wood/postcaps/index.htm
The Natural Philosopher
> I've an idea to create a memorial post for a departed friend which would
> consist of a domed metal cap on a 4"x4" post.
>
> I had originally though of making the cap of lead but a quick google
> suggest that lead "burning" is well beyond my skills & equipment levels
> so I wondered if either I can work the lead "panel beater style" to
> cover the top and extend down the sides for a few inches or whether I
> should consider a different metal like an aluminium alloy.
>
Tim Downie
That sounds like a good idea. Ta.
Tim
Tim Downie
Nah, for sentimental reasons it has to be domed.
Tim
Andy Dingley
> consist of a domed metal cap on a 4"x4" post.
Copper. Easiest to work, patinates nicely afterwards.
Tools are a variety of wooden, plastic or rubber mallets and also a
mix of treestumps with hollows in, or else sand-filled bags. Most
importantly, some sort of gas torch (or cooker) for annealing. You
need something with these tools, but they're not fussy and it's easy
to improvise. A cheap wooden egg mallet, or just a home made "lump on
a stick".
Source metal is scrapyard immersion heaters, or other scrap copper.
Web searching should give you techniques, otherwise any '50s school
metalwork handbook. Look for "sinking" and "doming"
Spamlet
Long time since school metalwork, but I would think making a ball from sheet
would be v difficult. Think you would need to make two 'bowls' and solder
them together. Also, the vandal and tea-leaf, dimension would mean that the
post has to be away from anywhere it can be seen. Even then, leaving it
hollow is inviting it to be squashed, however careful you try to be.
Using the wooden post top as a pattern, you might be able to cast one from
solid lead if you have a safe spot.
Think we've covered post tops before. I made wooden caps for posts on a
fence I made. Screwed them on with stainless. The local kids just split the
wood off with a screwdriver. Didn't seem worth the bother of trying again.
S
The Natural Philosopher
Tim Downie
> "Tim Downie" <timdow...@yahoo.co.uk> wrote in message
> news:i0kfft$oq1$1...@news.eternal-september.org...
>> pcb1962 wrote:
>>> On 1 July, 20:45, "Tim Downie" <timdownie2...@yahoo.co.uk> wrote:
>>>> I've an idea to create a memorial post for a departed friend which
>>>> would consist of a domed metal cap on a 4"x4" post.
>>>>
>>>> I had originally though of making the cap of lead but a quick
>>>> google suggest that lead "burning" is well beyond my skills &
>>>> equipment levels so I wondered if either I can work the lead
>>>> "panel beater style" to cover the top and extend down the sides
>>>> for a few inches or whether I should consider a different metal
>>>> like an aluminium alloy.
>>>
>>> Copper would be fairly easy, as long as you have a suitable wooden
>>> former. Wickes sell round balls for the top of newel posts that
>>> would be ideal, £9 IIRC). You'd need to anneal the copper a few
>>> times so a blowtorch would be handy. Any model engineering supplier
>>> can sell you a suitable piece of copper.
>>
>> That sounds like a good idea. Ta.
>>
>> Tim
>
> Long time since school metalwork, but I would think making a ball
> from sheet would be v difficult.
But I'm not making a ball, I just want a metal covered domed top to the
post, a hemisphere.
> Think you would need to make two
> 'bowls' and solder them together. Also, the vandal and tea-leaf,
> dimension would mean that the post has to be away from anywhere it
> can be seen. Even then, leaving it hollow is inviting it to be
> squashed, however careful you try to be.
Well yes, but then I wasn't planning on leaving it hollow. As you say, it
would make it too easy to dent.
Tim
Owain
> I've an idea to create a memorial post for a departed friend which would
> consist of a domed metal cap on a 4"x4" post.
Half a copper ball-cock ball?
http://www.flickr.com/photos/24343551@N04/sets/72157613028554429/detail/
6" copper float about a tenner from BES, 8" also available.
http://www.bes.co.uk/product/120~PL~2200~2200~-Plastic-and-Copper-Floats-.html
Other sizes here
http://www.mytub.co.uk/shop_display_products.php?cat_id=Copper%20Ball%20Floats
Probably easier to panel-beat an attractive dimpled finish into an
existing hemisphere than try and form a hemisphere from flat sheet.
Owain
Dave Liquorice
> Half a copper ball-cock ball?
>
> 6" copper float about a tenner from BES, 8" also available.
Good bit of lateral thinking, bit big for a the top fo 4" post but
> Probably easier to panel-beat an attractive dimpled finish into an
> existing hemisphere than try and form a hemisphere from flat sheet.
I agree, I'm no panel beater but just thinking about how a flat sheet
of metal will need to stretch and bend to form a hemisphere is
non-trivial. One might be able to get a half hemisphere without a
skirt fairly easily but a full one which self forms to a skirt would
be much harder.
--
Cheers
Dave.
Owain
> > Half a copper ball-cock ball?
The second link has 4.5"
It might be easier to change the size of the post ...
Owain
NT
If its a 4x4 post, thats 5.6" diagonal
NT
Matty F
> But I'm not making a ball, I just want a metal covered domed top to the
> post, a hemisphere.
I have a collection of chrome plated copper teapots that I bought for
a couple of dollars each, since people don't like using copper teapots
any more. Perhaps you can find something like that in junkshops. Or
copper ornaments that you can chop up.
dennis@home
"Matty F" <matty...@yahoo.co.nz> wrote in message
news:f75ef168-9f1e-4d50...@w15g2000pro.googlegroups.com...
He needs an old hot water cylinder, lots of copper sheet.
They can be found at scrap yards or where new combi-boilers are being
fitted.
Roger Dewhurst
Get a stainless steel bowl of the right size and hammer into into the
shape that you want.
R
Spamlet
"Dave Liquorice" <allsortsn...@howhill.com> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
Just reminded me of our old 'Ericson' tester: basically a metal ball pushed
into sheet metal to test it's ductility. We had stacks of little domed
plates... If you have a decent hydraulic jack or press and a metal ball and
ring to push it through you might be able to cold form your shape. Be bold:
you could even do something like jacking the car up with your plate and a
former between. You could hollow a block of wood and use your fence post
wooden ball, and the jack to push it in. Lots of uses for jacks...
If you are knocking up from scratch, the rim is the bit you are holding.
Finish it last, then cut off the excess with snips (or snips, then finish:
depending on how hard it gets). If memory serves that is...
S
Spamlet
"Owain" <spuorg...@gowanhill.com> wrote in message
news:8cc41b18-9966-42aa...@18g2000vbe.googlegroups.com...
You still need a good hard and smooth anvil of the right curvature to get a
decent finish - and polish the face of the hammers first. It is not that
difficult to form a bowl from sheet, but you need to soften the copper
regularly with a torch, and have a sandbag or similar to get the initial
shape with hard blows from a round headed wooden hammer. Then you have a
long but satisfying bout of 'panishing' tapping to do, to get the final
shape and hardness.
S
Spamlet
"Matty F" <matty...@yahoo.co.nz> wrote in message
news:f75ef168-9f1e-4d50...@w15g2000pro.googlegroups.com...
Or just pour lead into and tip out when cool... Any non-melty bowl shape
will do.
S
Andy Dingley
> You still need a good hard and smooth anvil of the right curvature to get a
> decent finish - and polish the face of the hammers first.
You don't desperately need either of these for this - work it with a
mallet into a bag. This will also work-harden it adequately, so won't
need a separate planishing step. As it's for outdoor use, not
polishing, there's no need to plansih it for the benefit of the
surface finish. Although you would need hammers for planishing, the
shaping is best done with softer mallets.
Andy Dingley
> Get a stainless steel bowl of the right size and hammer into into the
> shape that you want.
Not the easiest job, to work stainless like that!
Tim Downie
In the end, I got some roofing lead and have battered it into shape. Apart
freom needing a little trimming up, it doesn't look too bad. Now I need to
make sure that it stays there on top of the post. (It will be accessible to
the public). Any suggestions as to what kind of glue would be best?
Tim
The Natural Philosopher
Very few glues work in regimes of vastly variable humidity. Those posts
will MOVE.
Something rubbery and gap filling is possible, but that's about all.
Hot glue maybe.
pete
Most glues don't work with lead. The metal forms a layer of oxide which
is not strongly bonded to the underlying metal. It may stick for a
short time, but in due course it will come loose. Then you've got
differential expansion - the metal will expand/contract due to temperature
differences, more than the wood does. That puts more strain on the
joint and will cause the glue to crack.
Tim Downie
I really would like to avoid nails. The domed cap is meant to be symbolic
of a departed friend's bald head. Adding nails to it would lend it a
certain "Frankenstein" air.
Is there no heavy duty flexible mastic/glue that might stick if I were to
score the lead deeply on the underside?
Tim
The Natural Philosopher
mastic is a better bet than glue. I am trying to think of a rubbery type
product that adheres well to metal and is gap filling too. silicone
peels to easily from anything.
Maybe expanding foam would work..Hmm. That could be best of all. That's
fairly flexible and sure fills gaps.
Not as rubbery as one would like, but its flexible enough, and it sticks
like shit to everything.
> Tim
Andy Dingley
> Any suggestions as to what kind of glue would be best?
None. Thermal expansion of the lead is a problem.
Best solution is to lead burn strips of lead onto the underneath, then
nail those down with clouts. Then dress the dome back into place over
them.
Frank Erskine
Car body filler.
--
Frank Erskine
The Natural Philosopher
Tim Downie
> I've an idea to create a memorial post for a departed friend which
> would consist of a domed metal cap on a 4"x4" post.
>
> suggest that lead "burning" is well beyond my skills & equipment
> levels so I wondered if either I can work the lead "panel beater
> style" to cover the top and extend down the sides for a few inches or
> whether I should consider a different metal like an aluminium alloy.
>
> Of course I could just contract the work out to someone to do
> properly but I'd like to have a go myself.
>
> Any suggestions?
In the end, I decided that beating and shaping copper was beyond my skills
so I went for lead. I started with a circle of roofers lead flashing and
basically beat, pummelled and bent it into shape with a combination of
wooden mallet and G-clamps. Pretty crude but it seems to have done the job.
http://www.zen31010.zen.co.uk/images/leadcap.jpg
Against advice, I have glued it with something called Stixall made by
everbuild (http://www.everbuild.co.uk/products.php?q=stixall). Only time
will tell how well it lasts but it's seems bl**dy well stuck on.
Just in case anyone was interested in what I did in the end...
Tim