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View Full Version : Need someone to make a tube for me on the lathe - Sydney



missionaryman
21st December 2006, 05:29 PM
Hi - I need someone to make me a tube to reduce the diameter of my torch to use C batteries rather than D batteries. It can be out of wood or nylon or any solid plastic.
I don't currently have access to a lathe so I can't make one.

Very simple 37mm outer diameter, 27mm inner diameter 230mm long.

it's for a 30 year old chrome torch I'm restoring and modifying for fire starting eye blinding light output.

Cash or paypal, PM me if you're able to help

http://i82.photobucket.com/albums/j243/missionaryman/IMG_0549.jpg

http://i82.photobucket.com/albums/j243/missionaryman/IMG_0548.jpg

DJ’s Timber
21st December 2006, 06:05 PM
I can do it for you if no one in Sydney is availabe and post it to you.

I have an extension for my forstner sawtooth bits that can bore a hole in one pass.

missionaryman
21st December 2006, 07:46 PM
I just realized that most timber species will release their resin vapours at the temperature this globe runs at (about 400 deg C which nets down to about 150 after the reflector) which would foul the reflector and ruin the torch - it would have to be turned out of nylon or ertalon or derlin which all have good turning properties and good inertness under heat stress.

China
21st December 2006, 08:41 PM
Might be more a job for a metal lathe, just curious why do you want go down to c size is it just the cost. I have 3 cell D size maglite replaced the bulb with the new maglite LED unit, amazing difference batteries have been in use for 3 months.

missionaryman
21st December 2006, 09:58 PM
I'm going from 5 cells D alkaline to 6 cells High current NIMH to run a pelican 3584 high beam bulb overated at 7.2v, this produces 1150 lumens. To give you an idea of the brightness your MAGLED is rated at about 100 lumen but drops to about 70 after a few minutes when it gets hot.

hughie
22nd December 2006, 12:14 AM
I just realized that most timber species will release their resin vapours at the temperature this globe runs at (about 400 deg C which nets down to about 150 after the reflector) which would foul the reflector and ruin the torch - it would have to be turned out of nylon or ertalon or derlin which all have good turning properties and good inertness under heat stress.


Hmm this would best done on a metal lathe it would be a tough job on a wood turning lathe. It could be done, but it might work out expensive in both time and materials

Of the three, the most likely would be Ertalon or Derlin as they have a better ability to with stand the temps involved

http://www.espimetals.com/msds's/derlin.pdf
http://www.dotmar.com.au/products/nylon/ertalon_6xau+.htm
http://k-mac-plastics.net/cast-nylon-rod.htm

Also Ertalon or Derlin look to have far better machining qualities. Obtaining size would be easier. Nylon has the tendancy to 'push away' from the tool and its difficult to make any small cuts for finishing. Of the first two I would go for Delrin.

Have you considered 'Tecaform' it has a better ability with temps and an equeal machining ability
http://modernplastics.com/pdf/ENSINGER_Tecaform.pdf

It might be an idea to bounce your request off a supplier for a range of suitable plastics with prices.[Dotmar Plastics] I have a chunk of glass filled Ertalon 120mm dia x 650mm or there abouts in the workshop. It would run to about $600AUD+ conservatively.

missionaryman
22nd December 2006, 06:16 AM
I'd normally get this made by a friend in Belgium who I met on the candlepowerforums but he no longer has access to a big lathe. With shipping it costs about $11.

soundman
22nd December 2006, 11:25 AM
Ok the lamp runs at 400c..... behind the reflector runs at 150c....
So what sort of refractory gloves are you going to handle this thing with.
How long do you think the reflector or the front glass will last.
and how do you think the various connections and switching gear will stand up.

I work with theatrical lighting and I know what these tempritures mean and what the heat and light intensities do to components.

It is common in theatre lanterns to see reflectors burned, melted, lamp holders routinely fail, cabling and connectors deteriorate in a variety of ways.
Even the light alone causes damage to materials.

finding plastics that will handle 150C isn't all that easy or cheap. Finding any material that will handle 400C is much less easy.

the wood decomposing are the least of your problems.

150c that will burn skin on cantact.... what will the case tempriture be particularly near the head.

Oh BTW have you seen a halogen lamp explode..... yep they do.... high tempriture halogen lamps can explode quite spactacularly.....thus modern theatre lanterns have measures to retain the flying glass and the broken lense. I have seen even low wattage automotive halogens explode.
Buggered the reflectors in one of my super oscars that way.

BTW you do know that NiCad and NiMh are capable of delivering extreemly high currents..... conbine that ith some sort of welded short failure of the switch gear and you have yourself a very serious melt down.

A few years ago there was a popular battery powered TV flood light that used a NiCad belt pack there were a couple of instances where camera assistants got badly burned when the belt pack went into melt down.

If you are building this thing as a stunt.... fine ....but don't expect to use it as a daily user...... it will be a dangerous device both to the user and those arround.

cheers

arose62
22nd December 2006, 11:42 AM
Do you really need a cylindrical spacer?

Could you use 3 equally spaced inserts (rods or long thin rectangles) to take up the difference in diameter? This would also give more airflow, since heat seems to be becoming a concern.

Or, maybe just a ring spacer around each cell?

Cheers,
Andrew

Doc Ron
22nd December 2006, 01:50 PM
Looks like a good candidate for a Darwin Award. You know, what people can win when removing themselves from the gene pool.

missionaryman
22nd December 2006, 04:28 PM
The high pressure gas bulb is safely stored behind a 4mm thick schott borofloat lens, had several bulb failures in this type of set up using Maglites which usually only have a 3mm mineral glass or borofloat with no issues.
A catastrophic bulb failure normally ruins the reflector coating but these vintage lights have a solid metal reflector that has a hand polished coating which I have successfully re-hand polished. It also acts as a big heat sink.

Temperature out the front - it sets paper smoking in 20 seconds, on the head and near the neck is about 65 Celsius after 10 minutes and stays there for the full duration of the battery cycle (70 mins). About 70% of that heat goes out the front as light, if you place your hand onto the lens you can only old it there for a few seconds.

Have you considered that the average hand held rechargeable spotlight is a 100w high pressure halogen bulb (mine is 30w) in a completely plastic (flammable) host, using a plastic lens and a plastic reflector and SLA batteries capable of massive currents albeit with voltage sag and they pass safety regulations?

The light engine I'm using comes from a Pelican Big D SLA lantern built for firefighters in a more compact, plastic host with a very thin glass lens and is internationally safety certified with almost every abbreviation you can poke a pencil at.

Yes of course I know that NIMH cells are capable of very high currents which is probably why I referred to them as "high current NIMH cells" in my previous post. NIMH is a very safe chemistry and even with a dead short a vent is largely insignificant, and has most often caused a POP and some leakage which means a new cardboard liner.
This light is all metal construction and there are no plastic parts to melt or fail with heat causing a short.

This is about my tamest light, I have more and some are far more powerful, there's 0.5kg of steel heat sinking around this light and I wouldn't call it a stunt or a risk of any sort in careful hands. It's nowhere near as dangerous as some commercially available lights like the surefire M6 or R500 Scorpion, both running the same sort of outputs and current loads with lithium batteries that set houses on fire when they vent.

I don't think about how the switch or other components will stand up - I test them either to critical failure or to the extents of the bulb/battery capability, I have run this set up for 12 months now with daily use with no issues other than a damn annoying rattling battery stick so unless you can machine me an ertalon tube to stop that then there really isn't that much you can address that I already haven't.
thanks.





Ok the lamp runs at 400c..... behind the reflector runs at 150c....
So what sort of refractory gloves are you going to handle this thing with.
How long do you think the reflector or the front glass will last.
and how do you think the various connections and switching gear will stand up.

I work with theatrical lighting and I know what these tempritures mean and what the heat and light intensities do to components.

It is common in theatre lanterns to see reflectors burned, melted, lamp holders routinely fail, cabling and connectors deteriorate in a variety of ways.
Even the light alone causes damage to materials.

finding plastics that will handle 150C isn't all that easy or cheap. Finding any material that will handle 400C is much less easy.

the wood decomposing are the least of your problems.

150c that will burn skin on cantact.... what will the case tempriture be particularly near the head.

Oh BTW have you seen a halogen lamp explode..... yep they do.... high tempriture halogen lamps can explode quite spactacularly.....thus modern theatre lanterns have measures to retain the flying glass and the broken lense. I have seen even low wattage automotive halogens explode.
Buggered the reflectors in one of my super oscars that way.

BTW you do know that NiCad and NiMh are capable of delivering extreemly high currents..... conbine that ith some sort of welded short failure of the switch gear and you have yourself a very serious melt down.

A few years ago there was a popular battery powered TV flood light that used a NiCad belt pack there were a couple of instances where camera assistants got badly burned when the belt pack went into melt down.

If you are building this thing as a stunt.... fine ....but don't expect to use it as a daily user...... it will be a dangerous device both to the user and those arround.

cheers

missionaryman
22nd December 2006, 04:31 PM
Do you really need a cylindrical spacer?

Could you use 3 equally spaced inserts (rods or long thin rectangles) to take up the difference in diameter? This would also give more airflow, since heat seems to be becoming a concern.

Or, maybe just a ring spacer around each cell?

Cheers,
Andrew
now there's some lateral thinking, I'll try a few dowels
thanks

SawDustSniffer
22nd December 2006, 04:47 PM
as ive been stuck beond the black stump for years with long shipping periods for repaires ,i have turned into a bush macanic ( maineack whaterver )
Car Bog , between gladrap can be molded into most shapes
cover an old table with a layer of gladrap ,
mix up a heap of Bog
place 2 wire's eather side of the blob of bog
cover with glad rap and roll with rolling pin to get 5mm thick sheet
when the leftover bog go's rubbery,cut it to size , you will need a stencil made of paper , rap it around a 27mm stick ,( broome stick with A4 paper raped around it untill it's the right size )
hold it in place untill dry , then peal off the gladrap and join the two sides togeather with a new mix , walla "bush plastic moulding "

might have to look for a heat proof epoxy as i dont think "CAR BOG" will handle the 400c temp ,but it should still handle ok

tip : glad rap is a bit thin ,but workes ,orange or black bulders plastic wont leave waves in the surface like gladrap will

have fun , and ware gloves

hughie
22nd December 2006, 04:55 PM
now there's some lateral thinking, I'll try a few dowels


The dowels will most likely move around, all ending up on one side and back to battery rattle again. grrrrh :mad: :D

I think the ring idea is a good one, as it will control the movement of each battery. With a 5mm wall thickness you could also drill a few holes for circulation in each ring.

The rings could be made as a tight fit with a split to allow placement on the battery yet be held firm during operation.

You might consider using aluminium for the rings, cheaper, effective and perhaps more durable than the plastic.

Stuff! I just talked myself out of a job :D

Christopha
22nd December 2006, 08:09 PM
My only question is "WHY".... why do you need a torch that will burn the eyes out of a roo at 5 kms???

scooter
22nd December 2006, 09:22 PM
Easy - to be put in an Ettamogah (sp?) Pub cartoon :D

China
22nd December 2006, 09:40 PM
Christopha I think the short answer would be why not, your not one of poor blokes who have grow'n up are you

missionaryman
22nd December 2006, 10:08 PM
Initially I needed a bike light and about $500 got you about 300 lumen of yellow light with 90 minutes run time and 900g in weight so I did some researching and discovered the candlepower forums where I learnt to turn a 2C cell maglite into 1150 lumen for 35 minutes with a weight of 380g and white light + a $30 CNC machined aluminum clamp. All up about $200 and I can take it camping/fishing/mate impressing

It started with necessity then turned into a bit of an obsession.

soundman
22nd December 2006, 10:44 PM
If what you say is true there is some anomaly in your temp figures.

SLA batteries have a quite high internal series resistance.
NiCad and NiMh batteries are capable of delivering frightening amounts of current.

You seem determined.... have you looked at stock size aluminium tube.
or even trashing a "C" maglite for the tube.
You don't have to make up much to shim a "C" to a "D".
The aluminium will help with heat disipation.
You will need to keep you batteries as cool as you can.
Both NiCad and NiMh don't like the heat.... performance degraddes considerably with tempriture as you rise from zero C.

Iv'e built a few high power "torches" bassed on dichroic lamps or projection lamps. The gruntiest "convienient" lamp I came up with was a 24V 150 watt bi pin projection lamp. that lamp is cheap as chips and so is the base.


You can shoehorn a couple of SLA batteries into the back of a Par 56 housing if you move the reflector forward. You need to chop up a ray kit and do a lamp base conversion...... but its a screamer.
I've built a couple similar as stage props.
heat is less of a problem because you have a6 1/2 " aloy housing to work in that is meant for a 300 watt tungsten lamp.

cheers

missionaryman
23rd December 2006, 07:07 AM
Soundman - me thinks you need to join the candlepowerforums, there is a flashaholic hiding inside of you...

I found a heavy section cardboard core tube in the house last night, don't know what it came from but it did the job, I just don't like cardboard but I'll live with it for now. I use Kapton tape to protect the top battery from heat, the rest stay cool enough.Thanks

djevans
23rd December 2006, 10:27 PM
Try knead it I know that this can be use in high temps I have used this on exhaust systems that run above 500c.
David

soundman
24th December 2006, 10:46 PM
:D :D :D Believe me there is certainly a "go harder" eliment in theatrical lighting too.

they wern't happy with 500 watt or 1000 watt lamps so the made 650 watt and 1200 watt lamps to up the power a little..... & this is normal.

lots of people do lamp conversions........ hell some of the main line fixtures are some sort of modification or high power lash up made into a product.

Take the par 64 lantern........ its a 1000 watt headlight out of a heavy bomber stuck in a soup tin:eek: :eek:

Some of the early strand stuff is realy...... "Novel"... in the early days there wasn't a product to buy.... so the worked with what they could scrounge.

One of the popular mods in the UK is to take a "Strand pattern 23N" which started life as a 500 watt conventional tungsten and stuff a 1200 watt halogen lamp and a muffin fan in the back.
Even stock these things are screamers....... the reflector is a sphere with a hole in the front and the beam width is 9 degrees.

These will cut thru a wash from a couple of 1K fresnels running open white.

At the moment I'm still looking for the ultimate mirrorball spot.... I'm using a pair of 100 watt pencil beam driving lights at the moment but the beam isn't as flat and controlled as I would like and there is too much filament image.

Ahh its all smoke and mirrors... whoops sorry thats night club lighting.:D

cheers

tashammer
24th December 2006, 10:55 PM
what you really need are selectively bred glow worms that when you rub their little bellies, their tail light really glows. Have the tail poking into the end of an octagonal cylinder. The other end be non-polished. That way you get a LABTBOGL which is much better than a LASER, as well as being good for the environment.

soundman
24th December 2006, 11:13 PM
Righto tas...... post a picture when you've built yours:D :D :D

missionaryman
25th December 2006, 09:46 AM
Here are some photos, the battery back is 6 x 4500mah NIMH C cells for 7.2v 60 mins run time (bulb draws 4.3A)
The beamshot is taken in daylight with the flash on against a window that's letting the morning sun in!

http://i82.photobucket.com/albums/j243/missionaryman/IMG_0548.jpg

http://i82.photobucket.com/albums/j243/missionaryman/IMG_0549.jpg

http://i82.photobucket.com/albums/j243/missionaryman/PhotoLibrary-250.jpg

http://i82.photobucket.com/albums/j243/missionaryman/PhotoLibrary-249.jpg

Outdoor Photo

http://i82.photobucket.com/albums/j243/missionaryman/ROP_HOLA_beams003small.jpg

tashammer
26th December 2006, 03:13 AM
how about a Night Sun, but make it as a handheld flashlight

soundman
26th December 2006, 10:25 PM
Night sun in a hand held ...... no..... but one of the lighting companies has a night sun in a beach ball:eek:
It a helium balloon with something like 3 x 5K halogen lamps inside.... I believe there are bigger models.

cheers

HoutBok
27th December 2006, 01:32 PM
There are commercially available Universal Adaptors that enable you to use C or even AA batteries in a D housing.
Wouldn't these work - or would the heat be an issue?

missionaryman
27th December 2006, 02:28 PM
There are commercially available Universal Adaptors that enable you to use C or even AA batteries in a D housing.
Wouldn't these work - or would the heat be an issue?
no these wouldn't work because I'm using 6 C in a 5 D, with these I could only use 5 C cells as they would be spaced longitudinally. They would also fail due to the heat and they create a lot of internal resistance.

For now the cardboard is working well, seems to handle heat well and insulate the batteries too so I might change the title.

marker
27th December 2006, 02:42 PM
You could use dowel and put heat shrink over it to stop it moving. NiMH batteries give a higher voltage with increased temperature as shown by these tests, http://www.ruschkowski.se/Battery_Measurements.htm

Mark