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Thread: XML Build

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    Triple XML Build

    Feeling a little left out with all the new builds I had a spare 30 minutes so fired up the lathe and starting making a triple XML housing to suit the Cutter MR11 XRE triple optic. The body is all but finished but i still have to make the heat sinking rear cap for the hipflex. Problem is I'm not sure if I like the design, she's a bit boring. Maybe making it black will improve the look.

    As the driver is the hipflex anything up to 2800mA is possible although like Troutie has said 3 XML's at full tilt is silly bright. With any luck I can get the thermal design sorted to allow full power in a Queensland summer, for those fast downhill runs. Will just need a higher amperage pack to extend the run times.

    I also have a double and single XML on the drawing board. Just got to think of a housing design to handle the heat at full power.



    Last edited by brad72; 02-13-2011 at 06:15 PM.

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    Ha ha. spare 30minutes Git takes me all day plus some to get to that stage.

    you say boring. but not too much you can do with round and minimal

    looks ace to me

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    Thanks mate. Kind of felt bad since I was supposed to be working but light projects are just too much fun.

    My speed only comes from having a big lathe with a 2 axis DRO. This means I can take big cuts (up to 10mm at a time) fast and accurately. In saying that mistakes can happen just as fast

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    Quote Originally Posted by brad72
    Thanks mate. Kind of felt bad since I was supposed to be working but light projects are just too much fun.

    My speed only comes from having a big lathe with a 2 axis DRO. This means I can take big cuts (up to 10mm at a time) fast and accurately. In saying that mistakes can happen just as fast
    No one like a show off
    10mm at a time...let me translate that to my time..1mm at a time

    Looks good to me

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    Quote Originally Posted by troutie-mtb
    Ha ha. spare 30minutes Git takes me all day plus some to get to that stage.

    you say boring. but not too much you can do with round and minimal

    looks ace to me
    I'm with Troutie on this one. Looks great to me. Wish I had some machinery and the skill to use it to produce things like that

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    Brad I have made similar housings, for my qaud XR-E's and they take me well over a day but then again you could put my whole lathe in your chuck and give it a spin.

    Looks good.

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    ....and compared to the drill press crowd? stop complaining you two

    Looks good Brad. did you get the email from Cutters yesterday about the special on the triple boards?

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    Quote Originally Posted by emu26
    ....and compared to the drill press crowd? stop complaining you two

    Looks good Brad. did you get the email from Cutters yesterday about the special on the triple boards?

    I did get the email. Certainly is tempting because they do give a pretty good beam and have some good optics to choose from, and the price is right.

    In the mean time what I i am going to do is mill 3 x 14mm diameter by 0.5mm deep recesses in the housing to hold the led dies. The dies will be held down with some 2.5mm cap screws and I'll drill 3 holes in the housing to enable the posts of the optic to be secured. This way I can experiment with the optic at different heights away from the led since it was designed for an XRE led who's dome height is 1.4mm greater that the XML.

    As for the lathe, much as I'd love to share the her around at over 4 tonnes it's not easy to move.

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    Quote Originally Posted by emu26
    ....and compared to the drill press crowd? stop complaining you two
    and what about the dremel and file crowd? (cue the "tear aluminium with teeth and use stubble to finish" crowd getting all unctious)

    looks very tidy though. Is it from solid bar or hollow stock? I wondering how much depth you have to play with on the fins..

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    Quote Originally Posted by mattthemuppet
    and what about the dremel and file crowd? (cue the "tear aluminium with teeth and use stubble to finish" crowd getting all unctious)

    looks very tidy though. Is it from solid bar or hollow stock? I wondering how much depth you have to play with on the fins..

    Solid 6061 bar, about 40mm diameter with fins 1.5mm wide, 4mm air gap and stepped fin depths of 20mm dia, 18mm dia, and the last 4 at 16mm diameter. This gives a good mix of strength and efficiency. If i were to use a front bezel secured with cap screws a 45mm diameter housing would be needed. The hole through the center is 6mm, big enough for power wires to the leds

    Thats why it' so fast to machine. Turn down the bar to the desired diameter, drill the 6mm hole through the center, bore out the front where the optics fit, use the 4mm parting blade to cut the fins, part off the light, spin it round and bore out the rear housing then put the light in the mill to drill the fine holes securing the leds. .

    Picture of a similar housing in the lathe chuck (65mm bar stock for that light)

    Last edited by brad72; 02-11-2011 at 03:41 AM.

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    I was able to finish the body this afternoon and get the holes drilled for the leds and optic. I Tig welded an alloy block to the housing base and tapped it with an M5 thread to take the handlebar mount.

    Weight wise I'm pretty happy so now just to start assembling and give her a test run. I still need to make the rear cap that will also be the heat-sink for the maxflex but I really want to see how much heat it generates at 2800mA as this will govern it's size.

    Here's a couple more pics.




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    wow, that really is beautiful. I'm ashamed to say it though, but I hope that cable gland doesn't spoil the look. I get their functionality (I'm using one for my next build) but they look damn ugly IMO.

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    The LED end of your light is a fine example of a well thought out and neatly executed design.

    It looks like you used an end mill to create the bores for the LEDs to sit in. The ones I have are not flat on the bottom by a degree or so and would not create a flat surface when plunged in to the work. Are yours the same or are they flat?

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    Sharp looking package.

    I too, don't particularly care for the glands. Will a glued-in stain relief grommet work?

    That switch looks nice. Do you happen to know the model number/part number.

    Great work.

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    Thanks for the comments guys. Your all correct about cable glands, they either look good or completely crap. I also have some 4 pin right angle plugs and sockets that I can use so i'll see as the build progresses

    Vancbiker, i use end mills to achieve a flat bottom hole and slot drills for cutting grooves. I would say you have slot drills which is why your holes are not flat.

    P220C this is the switch I am using http://au.mouser.com/ProductDetail/A...2EfekDved/E%3d I just wrap the hole unit in some heat shrink and mount to the handlebar between my grip and brake mount with some velcro straps
    Last edited by brad72; 02-11-2011 at 01:53 PM.

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    Well the triple XML is nearly finished. I spun up a handle bar mount yesterday that is a clamp type, tightened with two M4 cap screws. I prefer this style as once it is tightened to the bar, there is no chance it can slip when the trail gets rough.

    To add some bling I used some glow in the dark paint inside the barrel where the optic sits as you can see in the image below. I still need to make the lens retainer which is why you can see a bit of wire holding the optic in at present.







    Next for some beamshots. Given the lack of trails open at the moment I used the paddock behind my house. The Horses in the shot are about 40 meters away with the houses in the distance about 110 meters away. The camera has made the beams a little brighter that they appeared to my eye but you get the idea. The 7up was still the brightest but the triple XML was not far behind. Check out the beam shots below.

    The 1st shot is a triple series wired XML with a cutter MR11 narrow optic for the XRE, driven at 2800mA



    This is the 7up series wired 4xXPG/3xXPE mixed board with a Kathod narrow optic driven at 1300mA



    This is a triple XPE series wired with narrow optic driven at 750mA. Woke the poor horse up in this shot



    This a daytime shot for some perspective. I realize now I need to find a paddock without tall clumps of weeds as they create too many shadows.

    Last edited by brad72; 02-12-2011 at 05:23 PM.

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    The XML makes a good bar light with all that flood.
    Good job on the Tig welding. People talk about lathes and mills. I want a Tig.
    Did you ano that light or use gunkote on it? It looks really good.

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    Quote Originally Posted by odtexas
    The XML makes a good bar light with all that flood.
    Good job on the Tig welding. People talk about lathes and mills. I want a Tig.
    Did you ano that light or use gunkote on it? It looks really good.

    Thanks OD. An AC/DC tig welder is a very handy tool to have in the shed. There are some very cheap quality units around these days as well.

    I ended up putting emissivity aside and painted it with a light coat of etch primer followed by light coat of satin black enamel. I'll strip the paint when I end up anodizing the other housings but I really wanted to see what she looked like black (no patience).

    As for beam shape she would make an excellent bar light but have 2 ot them with one of the helmet it will be that bright the floodiness wouldn't make any difference. For 3 leds it is ridiculously bright, although it will chew through the battery @ 2800mA
    Last edited by brad72; 02-13-2011 at 01:46 PM.

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    Quote Originally Posted by Vancbiker
    The LED end of your light is a fine example of a well thought out and neatly executed design.

    It looks like you used an end mill to create the bores for the LEDs to sit in. The ones I have are not flat on the bottom by a degree or so and would not create a flat surface when plunged in to the work. Are yours the same or are they flat?
    Mate, my apologies, i just had a look at my end mills in the tool box and they all have a slight relief (2-5) which will leave a dish shape and some are perfectly flat. Without the relief the end mill will do funny things when cutting.

    I have had my 14mm end mills for some time now as I don't use them often and I do remember grinding end mills many moons ago to get a perfectly flat base, this must be one or them. Alternatively you could use a counterbore like these ones http://www.harveytool.com/products/p...oduct_id=23300 and save the hand grinding that will either work or not. Only other option and the cheapest is to grind a 14mm drill completely flat, bore the hole 1st with the end mill, then follow with the drill to flatten out the dish.

    sorry for the confusion.
    Last edited by brad72; 02-13-2011 at 07:49 PM.

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    Quote Originally Posted by brad72
    Mate, my apologies, i just had a look at my end mills in the tool box and they all have a slight relief (2-5) which will leave a dish shape and some are perfectly flat. Without the relief the end mill will do funny things when cutting.

    I have had my 14mm end mills for some time now as I don't use them often and I do remember grinding end mills many moons ago to get a perfectly flat base, this must be one or them. Alternatively you could use a counterbore like these ones http://www.harveytool.com/products/p...oduct_id=23300 and save the hand grinding that will either work or not. Only other option and the cheapest is to grind a 14mm drill completely flat, bore the hole 1st with the end mill, then follow with the drill to flatten out the dish.

    sorry for the confusion.
    No problem. I know that flat bottom end mills are available, just not nearly as common as relieved end style. All the ones I have are re-sharpened "discards" due to being too small for the production shop to use. Beggars can't be choosers in this case. Anyway this info may be helpful to others that do milling as something to watch for.

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    If I'm cutting a round flat bottomed hole with an end mill or slot drill I remove most of the material with the largest end mill or slot drill.
    Then I switch to an end mill or slot drill that is half the od of the hole I'm cutting. So 20mm ill use a 10mm to finish off.
    This is done on the rotary table on my mill, this gives me a flat bottom..as I have to move the table to cut half the width of the hole..then rotate the rotary table..

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    Quote Originally Posted by Goldigger
    If I'm cutting a round flat bottomed hole with an end mill or slot drill I remove most of the material with the largest end mill or slot drill.
    Then I switch to an end mill or slot drill that is half the od of the hole I'm cutting. So 20mm ill use a 10mm to finish off.
    This is done on the rotary table on my mill, this gives me a flat bottom..as I have to move the table to cut half the width of the hole..then rotate the rotary table..

    I used this dremel cutter to create such flat bottom:


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    Brad72, what is the heat gain like?

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    I haven't fired the light up for some time but from memory it wasn't too hot on full power. The heatsink area is quite large but I can't find my cad file so I am unable to tell you how many square inches.

    What I'll do is fire it back up again and attach a thermocouple to the body and see just how hot it gets.

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    Thanks!

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    Ok, i put the light on the back fence in an ambient temp of 11 degrees and no wind. After 15 minutes @ 2800mA the housing had settled out @ 65C. Not bad really considering there was no air movement across the housing. Once moving however the temp drops nicely to being just warm..

    I must say compared to the twin xml I have just made this light is truly incredible. I reckon the twin on the helmet and this on the bars and night will turn to day.

    Just for specs on full power of 2800mA with a 14.8v pack the triple draws 2.02 amps. The twin xml on 2800mA draws 1.37 amps from a 14.8 volt pack.


    Here a picture of the leds wired up. I should have posted that earlier. The 3 holes you can see are for the posts of the triple optic.

    Last edited by brad72; 06-24-2011 at 03:31 AM.

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    Wow, thats not bad at all considering it just under 30W? of heat. Thanks for all the trouble, I really appreciate it!

    Quote Originally Posted by brad72 View Post
    I must say compared to the twin xml I have just made this light is truly incredible. I reckon the twin on the helmet and this on the bars and night will turn to day.
    Totally agree, from the few beam shots I could find of the optic and leds it really amazed how much light such a small optics can deliver.

    Hope you don't mind me posting this here:
    I'm building a light for myself with the same leds and optic and with my own design, but I live in a warmer climate...the average "low" even in winter is 17degree C so I have the problem with getting the heat sorted. The design is still on paper (computer model actually) and a nice guy over @ CPF ran a thermal simulation for me at his work place so I could get an idea for the heat but the initial design was running way to hot...around 260 degree C ...and it was only stable on 60 degree C at around 19MPH air flow over it. My fins are running length wise to allow better air flow. And I've refined the fins to get more surface area after the thermal test. Will start a build thread and if you maybe have a look and some advise..?

    Thanks again!!

    Eduan

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    No problem eduan. I am always happy to help.

    I to live in a warm climate and do a lot of night rides in summer where the ambient temperature can be around 28 degrees so I like my housings to be as thermally stable as possible, but like you said 30 watts is a lot of heat to dissipate.

    Fin orientation is always a bit of an issue for debate. The light in this thread has the advantage of convection cooling when stationary as the cool air below the housing can travel unhindered through the fins and out the top which isn't as easily achievable with fins running parallel to the air flow especially if you want a fast to machine housing. To be honest I have found both style of housing to work equally as well because once you are moving the cooling effect of moving air is excellent.

    I look forward to seeing you design. It's always fun seeing them come to life from a Cad drawing

    Brad

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    Would this work for a Night Lightning housing by any chance? They have a lot of heat sinking.

    Not that I need that much light, but my old iBlaast II is getting long in the tooth.

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    Brad72, Where did you buy the aluminium bar from? I have been looking but cant seem to find anywhere.

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    Quote Originally Posted by mitchellluke View Post
    Brad72, Where did you buy the aluminium bar from? I have been looking but cant seem to find anywhere.
    Hi mate. I got it from my local metal suppliers. It's 6061 free machining bar. Where are you located.

    I have noticed an Aussie ebayer selling bar stock but a steel supplier would be cheaper. If you can't find one let me know and I'll get you some and put it in the post

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    mitchellluke I assume by Victoria you mean a southern state in Australia?

    If yes you can try Capral aluminium.

    Otherwise try one of the suppliers listed on this page

    I'm in Sydney and I have bought from Ullrich and Comalco but I think comalco are now owned by RioTinto and they don't show up in the online phone books and it doesn't appear as though you have an Ullrich's south of the border.

    Hope that helps.

    Places like Bunnings do sell a selection of both bar stock and hollow sections / profiles but don't think they'll go as big as this.

    Good luck and welcome aboard. Make sure you post your build so we can all enjoy it.

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    Bummer...been trying to get a build thread started but my post count is too low. Will have to do something about it then I'll let you know if got the thread up.

    Had a thought about what you mentioned... and realized my design purely relies on moving air (from the front only) to cool it down, and when standing still the housing would act as a solid because there would be no cold air to be able to get to the fins from below. Will see if I can get a combination of length wise fins and vertical fins going, but I think it would be hard to machine.

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    Thanks for the fast and detailed response! Gotta say that this community is very helpful!

    emu26, yes Victoria, Australia. Good old regional Victoria.

    Going with the triple XM-L with Cute-3-XM-SS optics and H6Flex, just waiting on the order from cutter.

    Being my first bike light i will have built, i think it may bitten off more than i can chew. So i think ill do a similar design to what brad72 has done, since i only have access to a lathe.

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    Rekkie, check your private message box.

    Mitchell, how regional? If you're talking in one of the farming belts then call into your local fabricators shop or even mechanics and ask if you go through their scrap bin.

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    Not extremely regional, 70km from Melbourne.

    Called at least 15 aluminium supplies and only capral could help me out with 1.2m lengths that might have to do.

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    Quote Originally Posted by mitchellluke View Post
    Being my first bike light i will have built, i think it may bitten off more than i can chew. So i think ill do a similar design to what brad72 has done, since i only have access to a lathe.
    Mate don't knock yourself up about a lathe made light. I feel that the lathe turned lights I have made are the best to be honest. They are fast to machine and I have had no thermal problems at all. The lights made on my mill look nice and you can be a bit more creative but they take 10 times longer to machine and thermally I have found no difference. You can always add a vertical mill slide to you lathe and do some milling on it, or buy a mill as well as long as SWMBO can be talked around

    Regarding your machinable alloy bar I am paying $60/meter for 42mm bar and $50/meter for 50mm bar if that helps.

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    Quote Originally Posted by brad72 View Post
    Mate don't knock yourself up about a lathe made light. I feel that the lathe turned lights I have made are the best to be honest. They are fast to machine and I have had no thermal problems at all. The lights made on my mill look nice and you can be a bit more creative but they take 10 times longer to machine and thermally I have found no difference. You can always add a vertical mill slide to you lathe and do some milling on it, or buy a mill as well as long as SWMBO can be talked around

    Regarding your machinable alloy bar I am paying $60/meter for 42mm bar and $50/meter for 50mm bar if that helps.
    I totally agree with a lathe made light is the simplest.

    And the alloy bar from capral was $62/1.2meter for the 42mm Dia. so i think i found my option, but was hoping to get a smaller piece to get the cost down. But now i suppose i can make several

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    Hi Brad, I had not seen this light before, and it looks great. The bar mount is a serious clamp, can't see that light budging at all. Thanks for posting the temperature test results. The number of fins on your light has me thinking about the tiny fins on the one I am building, which may not be sufficient for 4 XML's.

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    Quote Originally Posted by HuffyPuffy View Post
    Hi Brad, I had not seen this light before, and it looks great. The bar mount is a serious clamp, can't see that light budging at all. Thanks for posting the temperature test results. The number of fins on your light has me thinking about the tiny fins on the one I am building, which may not be sufficient for 4 XML's.
    Just ride faster Huffy and all will be ok. No seriously a lot depends on the outside temp and how fast you are going. If riding up hill most of us would drop the power to low anyway to improve battery life so really the light is only operating on full when you are going faster.

    This light was a proto and I think the next light will have a different fin arrangement but this one works fine so it's more that I like to fiddle.

    The mount was nice and simple just being turned from some alloy bar then drilled in the mill. The last thing I want is for the light to rotate when flying downhill. I had that happen once and learnt my lesson. The light spun around on the bars and was pointing right into my eyes. I didn't know what the hell was happening as it gave me such a shock that i crashed into the lantana. After about 15 minutes later my night blindness and bright spots in my eyes subsided and could assess the damage which luckily was minimal. Makes for a good story though.

    Had i been using the old 2 C cell halogen light this would not have been a problem as a condle would of been brighter so I guess this is one of the risks of our super powerfull lights

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    Mitchell, I may not build the best lights here but let me give you some advice that I'm pretty sure most here will agree with.

    FORGET ABOUT 1.2M and save yourself some time and money by buying the stock 4m or 6m lengths. I have no doubt that once your first light is built there will be another. Once your mates see it, they will suddenly be your best mates

    Brad, those prices are killing me. I paid under $100 for a 4m length of 40mm square bar from Comalco. come to think of it, maybe that's why they aren't around any more.

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    Quote Originally Posted by emu26 View Post
    Mitchell, I may not build the best lights here but let me give you some advice that I'm pretty sure most here will agree with.

    FORGET ABOUT 1.2M and save yourself some time and money by buying the stock 4m or 6m lengths. I have no doubt that once your first light is built there will be another. Once your mates see it, they will suddenly be your best mates

    Brad, those prices are killing me. I paid under $100 for a 4m length of 40mm square bar from Comalco. come to think of it, maybe that's why they aren't around any more.
    That's the unfortunate price of convenience. I could order it in cheaper but a 5 minute drive and no freight wins every time. I think your right about Colmalco if they were letttng bar go for that price. You'd nearly get more money for scrap.

    This is why I am giving some thought to doing my own alloy casting using either lost foam or by making a mould. So many ideas, so little time.

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    I'll Take the advice and purchase a 3.6m length. Cant wait to start building

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    Casting Aluminium Alloys

    Quote Originally Posted by brad72 View Post
    This is why I am giving some thought to doing my own alloy casting using either lost foam or by making a mould. So many ideas, so little time.
    Hey Brad,

    you do such fabulous work it makes me wish my skills extended beyond weilding an angle grinder pr at least that I had a better class of friends .

    Are you sure about casting ali alloy though ?

    The reason I ask is that when I suggested cating ali to my live in metalurgist I got a smack upside the head. The subsequent lecture I received went something along the lines of "aluminium as a solid oxidises to form a passivated layer. While aluminium does have a low melting point, as a molten metal, there is no passivated layer and it oxidises rapidly. Casting aluminium needs to be done under a reducing atmosphere to prevent oxidation"

    I have read of others home casting aluminium, but SWMBO was adamant that it will not be happening at our house.

    Cheers

    Bruce

  45. #45
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    Bruce, tell SWOMBO that it's ok to make a mistake occasionally.

    Then show her this done by aaron04.

    He has done several build threads
    First one
    Second
    Arguably his best

    Once she has apologised, then you can start to talk to her about home anodising

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    Quote Originally Posted by find_bruce View Post
    Hey Brad,
    Are you sure about casting ali alloy though ?
    You make a good point Bruce but where there a challenge someone will take it on. It's always a shame to see the 6061 alloy off-cuts sitting around so it would be lovely to turn them into something. The furnace is easy enough to make so really it's down to the technique. The links that emu posted certainly show what can be done. I guess the important part will be to oversize the castings so the oxidation can be removed after casting...i think

    Lost foam will give the best surface finish but it is also the hardest to do for a diyer. Maybe I'll just start with simple sand moulding and see how it goes.

    As for SWMBO, as long I keep up the good loving, shoes, handbags and jewelry i think i can get away with anything. Failing that I'll just nag till she says yes I am the boss though and she doesn't scare me at all Sh-t, I hope she's not looking over my shoulder...phew..i'm safe

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    Thanks for the encouragement emu. Some interesting facts about my beloved is that her undergraduate thesis was on metal fatigue in 303 shell casings & she is a crack shot over 1000 yards, Definitely a woman to be respected. If I were so brave as to follow your advice, I suspect she would point to

    • this photo and this photo as evidence of porosity.
    • troutie's post in relation to the results being soft and not easily machineable; and
    • point out that the soot referred to in casting steel is carbon which is a reducing agent (ie to reduce the level of oxidation) & it doesn't work with aluminium because aluminium is a stronger reducing agent than carbon.

    Brad, the last pair of shoes I bought for her were a pair of steel capped safety boots. Sure they were Purple Boots, but I was spared the necessity of looking for a matching handbag

    Sure you can easily melt aluminium and cast it to a shape, but the question is the physical properties of the result. If I have understood my lecture correctly, the issue is more like the difference between wrought iron & steel.

    Perhaps an example that is closer to home. 6061 is commonly used for bikes because it is easily machineable and is weldable. When they first started welding aluminium bike frames, they had a disturbing tendency to twist out of alignment & the metal surrounding the weld loses much of its strength. Both of these are now addressed by careful heat treatment.

    There is a considerable art in the heat treatment of ali alloys to achieve various properties -the question is what properties do you want in the result ? 6061 for example commonly comes in 3 different heat treatments, O, T4 and T6, each of which have difference thermal conductivity, although they are probably close enough for our purposes.

    It seems that casting causes a reduction in the thermal conductivity as well as changes in other properties. Whether that is significant in a bike light is a matter that experimentation will teach you.

    Given the high standards you set, I am happy to sit back and wait to see the results.

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    Thanks for all the info Bruce. Like I always say you never stop learning.

    Sure they were Purple Boots, but I was spared the necessity of looking for a matching handbag
    If only life were that simple

    Sure you can easily melt aluminium and cast it to a shape, but the question is the physical properties of the result
    Porosity is something that I hadn't given much thought to, nor the weak structure. I predominately have 6061-t6 lying around so that part is covered. As for how much flux to add, temperature prior to pouring, size of the chimneys etc etc is something still to learn. One thing for sure though is that the kids are not going to be in earshot after the 1st, 2nd, 3rd pours as I cannot see the results being pretty. I can also see much trial and error before a usable result is achievable.

    The biggest problem I have is the fabulous images in my head of how the castings will turn out when i finally get around to doing it. Bit like when I look in the mirror and think how buff I look, only to be shot down by the other half when she come in and says, nice man boobs

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    I might try this tomorrow. Essentially there is twice as much fin surface area so it will be better for full power slow riding or faster riding with better efficiency as we all know the cooler a led runs the better the output.

    Weight wise it is 140 grams and will use the triple otic and the hipflex driver mounted in the rear. I have improved the hipflex heatsink also to improve it's efficency.

    Don't know if I like the look of it so I might just make it an see how it turns out.


  50. #50
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    Quote Originally Posted by brad72 View Post
    I might try this tomorrow. Essentially there is twice as much fin surface area so it will be better for full power slow riding or faster riding with better efficiency as we all know the cooler a led runs the better the output.

    Weight wise it is 140 grams and will use the triple otic and the hipflex driver mounted in the rear. I have improved the hipflex heatsink also to improve it's efficency.

    Don't know if I like the look of it so I might just make it an see how it turns out.
    I'd be happy to hide your rejects Brad

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