Beginner question: coating plastic with titanium

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Hi,I am very sorry if this question is thrown around a lot ... I tried searching for "titanium" and "coating" & did not come up with anything.I would like to make a Titanium-Coated Knee Slider, as seen here. It's a plastic puck that is glued/stapled to velcro which is then attached to the knees of a leather motorcycle racing suit. The pucks touch down when the motorcycle is cornering, and the titanium causes a sparking effect as it hits the pavement at high speed (seen here). (There is no performance benefit to adding titanium to the plastic compound, it is just for show.) The manufacturer who made the pucks in the image discontinued their use a number of years ago, and no one else has picked it up.I'd like to find someone to make some of these pucks for my friends and I, but I have no idea even who I would approach for something like this. What is the process used to get the titanium to coat the plastic? What kind of welder would I approach for this task and how do I find him/her? Is it even a welder that I need? Is this a difficult procedure or a straightforward one? Is this something I could learn to do myself in a couple months?Thanks for any help
Reply:It's not a coating.  There's a solid piece of titanium on there.  Like a brake pad, it can be riveted, or glued.  Bolting might work too.Zirconium also gives nice white sparks BTW.
Reply:No it's definitely coated. I used to own a pair.Zirconium huh? Nice tip. I heard that magnesium also sparks but it's not as bright and somewhat unstable?
Reply:Although I should mention, if the entire thing was made from titanium, that would be fine - better, even. Then the question becomes, where do I find someone who can cut a piece of titanium in the required dimensions, and is the cost going to be prohibitive (I'm thinking $200 per set has to cover materials + wages to the welder)
Reply:Magnesium isn't going to spark so well.  You could just buy a piece of titanium on eBay and rivet it on.  Its a little difficult to cut (slightly more so than stainless), but not unworkable.  CP titanium is softer than 6-4 or other alloys, and would be easier to work with.  Zirconium is softer still, but the cuttings can spontaneously combust.Maybe cut something like this in half:http://cgi.ebay.com/ZIRCONIUM-metal-...item588ca0dee0Zirconium sparks so well, it sparks from WATER jet cutting:[ame]http://www.youtube.com/watch?v=WLATUxjKgpE[/ame]If you know someone with a plasma cutter, cutting it to shape would be seriously easy.I've seen these before, but they always had a replaceable block of metal that bolted to the plastic on your knee pads (or elbow).
Reply:That vid looks crazy!! hehe. It's not dangerous or anything is it? I mean could this "spontaneous combustion" bounce off and start a fire in some grass on the side of the road?
Reply:Your going to want to look at riveting or bonding a sheet of Ti to your plastic puck, metals cannot be "welded" to plastic.Have we all gone mad?
Reply:Ok, I called around to some local welding shops and they seemed like they would be up for the job, but no one had the right size Ti or zirconium in stock, so I ordered the zirconium plate rlitman suggested, plus another, and a ti plate & ti ingots from the same seller. Man that zirconium is expensive! I will have to find a cheaper supplier than ebay if I wanted to make a few sets for friends, but everything I've found online so far wants bulk orders.So, I will wait for the materials to arrive then go over to the shop and see what they can think of.
Reply:Yeah, those aren't cheap alloys.  They're expensive to produce, and difficult to work with.Buying little scrap cutoffs from other jobs is the only way to make this kind of project affordable.  On the bright side, with some thickness to the metal, these should last a bit.Just one thing I learned from drilling titanium (to rivet it on):  That stuff seriously work hardens.So, you need a razor sharp drill bit (preferably cobalt), and go slow on the RPM's, but push hard.  If your not pushing hard enough, it hardens under the point you're cutting, and you'll never get through.
Reply:I've seen some stunt bike riders with titanium skid plates on their cycle boots that they would spark by jumping off the bike at a moderate to high speed and skid across the pavement on their feet like they were just standing next to the bike.  This might be something else to consider if you and your friends are getting into stunts and tricks on sport bikes.  I also saw another guy who had what was most likely zirconium tabs attached to either the palm or fingers of his left hand glove and he would skim the pavement in a hard left banking turn causing sparks.  May have had to have extra insulated gloves for it.
Reply:yeah I have seen the skid plates in a film but not in person. I think those would be annoying to try to walk around on heh, but more importantly the plates would interfere with available grip on your footpegs during cornering, during stand-up wheelies etc.Skimming the pavement with the left hand would be quite sick ... are you sure it was his hand and not his knee? It's pretty tough to take a hand off the bars at the point where you are close enough to theoretically be able to touch the ground ... and taking your inside hand off would be tremendously difficult because the amount of weight you have on it at that point and the sensitivity of the steering inputs. I guess it would be fine if you were on a little pocketbike at low speed or something heh, but anything else would be very tough.
Reply:the zirconium and titanium arrived today! I am very impressed with the sizing, I will only have to do cutting on one of the Ti plates. I am meeting up with a friend who is a farrier tomorrow. He seems to think that we might be able to glue the metal plates to the plastic pucks with a special glue he uses on horse shoes. I am not sure if the glue will hold when the metal is skidding across the pavement at 100 mph or so? What do you guys thing?
Reply:Well, I must defer to a farrier.  He's got to have plenty of experience with this sort of thing (some horse shoes are even made from titanium), so maybe he'll have a better answer when he looks at it, but I would be more concerned with the glue holding to the plastic (which may flex while in use and is harder to glue to than a hoof) than to the rigid metal.That, and it could get hot and melt the glue.If you could get a couple of pop rivets in there in addition to the glue, you should be golden.
Reply:Consider the weight of a horse and the strength of the impact it makes on the ground when its running at full speed.  The average horse weighs in at around 1000lbs/453Kilo the force the horse makes with its hooves while running on the ground when the hoof makes impact is impact and friction based in a downward and backward motion which at acceleration is more violent than when the horse is maintaining a consistent speed.  To figure out what the total average is at acceleration and maintaining would take someone with some physics knowledge and I'm about 6 months away from studying it but at least this gives you some idea as to how well that glue works and should hold the plates to the plastic pucks.
Reply:yeah but my bike has the power of 160 horses  so I am sure the glue is very strong but is it strong enough? hehe I will test it with the titanium ingots first, those were only $2 each or so.rlitman, good point about the glue melting! I will be sure to mention that, given that some types of plastic compounds have been known to melt and fall apart.
Reply:Do a safe test and glue one to a puck then secure it to something suspended a few feet off the ground then figure out a way to suspend adjustable weight from it up to say 500lbs then do a bounce test on the weights to see how it goes.