paul8899 Posted July 3, 2009 Report Share Posted July 3, 2009 hello, got a bloody great big cnc machining centre delivered at work this week and I've been told that I can make some test pieces on it to get the hang of using it Ive decided on making a set of wheels for my R1 and I have a couple of technical questions about it whats the best type of ally to use ? do the wheels need to be heat treated after machining to take the stress out or does this only depend on the type of ally used ? whats the wall thickness ? , I was thinking of 3mm with 25mm x 12mm with 8 spokes , would this be strong enough ? whats the diameter of the sealing face,are they exactly 17in or is there some clearance ? whats the acceptable run out on a wheel ? I can get both sides running dead true after machining but if they need heat treatment after machining I might have to remachine them I don't think they'll distort that much , reckon on abt .005 / .010 ( .012 / .25mm ) would that be too much ? I'm going to hopefully make a small rear wheel in a couple of weeks to see what it looks like Any help would be greatly appreciated Thanks Link to comment Share on other sites More sharing options...
bezzer Posted July 3, 2009 Report Share Posted July 3, 2009 I haven't got any answers for you but I'd just like to say... YOU JAMMY BASTARD With machinery like that haven't you got some decent engineer boffin at the firm or at least access to one that can answer most of the queries with a bit of authority so you don't fuck it up. Link to comment Share on other sites More sharing options...
beek Posted July 4, 2009 Report Share Posted July 4, 2009 Paul Making wheels is a art and best left to the pro, s who know what they are doing the obvious reasons you don't want them to break. Link to comment Share on other sites More sharing options...
porter_jamie Posted July 4, 2009 Report Share Posted July 4, 2009 you need the ETRTO book. it costs lots. dont try without Assuming youre going to make it out of one piece billet, you sure you got enough travel, especially in Y? and to do the profile, you either need a huge rotary table, or a huge lathe. And the billet is going to cost about 1500 quid (estimate) per wheel just for HE30 And if youre going to use the wheel in a proper bike, not some show tractor, you really ought to do a fatigue test, and some basic strength calcs to convince yourself it wont fail on you. If i was doing it, and i wouldnt cos carbon dymags are only a couple of grand, i'd use 7075T6. It will weight loads more than a stock wheel as well. Link to comment Share on other sites More sharing options...
lorenzo Posted July 4, 2009 Report Share Posted July 4, 2009 If you want to do something 'posh' with it then there's loads of other options that are better for one reason or another. Yokes wouldn't be a bad idea, or if you're feeling really swish, a set of cases to make an RD350 into a V4 700. Now that would turn a few heads. Link to comment Share on other sites More sharing options...
paul8899 Posted July 4, 2009 Author Report Share Posted July 4, 2009 hello, the machines travel is 40 x 20 ( 1016 x 660 mm ) so it will fit ok and I,ve got a mate with a big nc lathe to do the outside (inside) of the rim I was going to machine one side of wheel in one, if I go deep enough to clear the spokes and have the inside of the rim as a register I can then turn it over and then machine the other half out without having to worry about the rotation of the spokes. Then get the bit where the tyre sits turned not too sure about the cost of material though , I know I can get L168 ,I'll have to get a quote for HE30 /7075 . hopefully the cost won't be a problem Shouldn't take more than 5hrs per wheel from start to finish We have the software at work that can check fatigue but I don't know them well enough to ask them to check it , I was going to basically copy a braking set with the rim the same as my originals. What type of ally is used in the original wheels ? My thinking was that if west coast choppers can make them I'd be able to Might try a set of yokes first but to be honest once you can program those apart from the size there isn't that much difference . Just have to load the program into the machine , set the tools ( making sure they dont ram the machine ) push the button and come back a few hours later and it " should " be finished . I made a steering damper bracket to fit the 5pw yokes I bought and that took just over an hour to program and machine. Which is pretty good for a 1st attempt at programming/machining not too sure about crankcases , little bit advanced for me always wanted to put 2 rgv engines together though !!! Link to comment Share on other sites More sharing options...
2639 Posted July 4, 2009 Report Share Posted July 4, 2009 I'm not the type to get windy about none production bits, but lightweight wheels is a step too far, personally. The shape of the taper / bead sealing area is key too. Perhaps consider Compomotive split rim outers with your own hub/inner section. Have helped make a drag race wheel once. We went the production outer route. And made it extra strong Link to comment Share on other sites More sharing options...
Jay Posted July 4, 2009 Report Share Posted July 4, 2009 Ooh er your brave, top man! I cant help but puleease put up the pics when you have done them.. Link to comment Share on other sites More sharing options...
bache Posted July 4, 2009 Report Share Posted July 4, 2009 push the button and come back a few hours later and it " should " be finished LOL, famous last words. You just programmed a brand new machine centre and you dont watch the first off througth! Braver than me! Good luck any way just watch you dont bump the mc im sure that wouldnt go down well with the gaffer when he finds out what your making! I work with mazak cnc lathes, always handy being able to knock things up at work, althougth ive never tried making anything like a wheel. If your machine is CAD/CAM rather than old skool ISO programing, when you design the wheel in CAD you should be able to find the weight of the wheel if you enter the correct data, might give you some indication to the strength etc, then you can add metal in places etc, without machining anything and producing some scrap. You can also compare the weight to a cast wheel to see if your wasting your time. Remember if your making it based along the lines of a forged wheel, you will have to add more metal to get the same strength. You can use less metal to get the same strength when an ally is forged, due to the way the metal grain flow when forging. I work with aerospace steels rather than ally, but if i was you i would look into stress releiving afterwards, removing that amount of metal from a billet you could have problems with cracks that arnt visable to the eye. Just an idea, id hate the idea of the wheel failing at 150 mph! Link to comment Share on other sites More sharing options...
paul8899 Posted July 4, 2009 Author Report Share Posted July 4, 2009 The cad/cam program we have got is called oncnc and it simulates the toolpath , my friend has used the same system for ages and he said that if the program says it will work it does " usually " I've been looking at the braking wheels and they have tapered spokes, I was going to make mine square (25mm with 8 , 17mm with 10 spokes) with a 20mm rad in the corners , leave the hub wall a mill or so thicker and have 15x3mm strengthening rib on the outside the rim ( hidden by the tyre ) which would have a 3mm wall As a rough figure how much thicker would it need to be comparable to cast ? Im not too bothered about the weight of the wheels, so long as there not mega heavy. I just want to see if I can make a set from scratch (would look good on my cv) The ally I was thinking of using is L168 , which is aerospace grade , just found some data sheets on the net , L168 has a similar strength but isn't as resistant to corrosion as 7075 so Ill have to get them hard anodised after machining . Maybe they are the same as magnesium wheels in the corrosion aspect ? We have an x-ray machine at work so Ill get them x-rayed before use I'll get them stress relieved as well just to be sure , would the stress relieving make the wheels stronger ? I was going to copy the original sealing area off the original wheel , just not sure about the diameter ( is it exactly 17in? ) Your not the only who wouldn't want them falling apart at 150 Not sure on the timescale on making them though , have to fit them in with work As soon as they are done Ill post pics up Link to comment Share on other sites More sharing options...
2 smokes 4 ever Posted July 6, 2009 Report Share Posted July 6, 2009 hello, got a bloody great big cnc machining centre delivered at work this week and I've been told that I can make some test pieces on it to get the hang of using it Ive decided on making a set of wheels for my R1 and I have a couple of technical questions about it whats the best type of ally to use ? do the wheels need to be heat treated after machining to take the stress out or does this only depend on the type of ally used ? whats the wall thickness ? , I was thinking of 3mm with 25mm x 12mm with 8 spokes , would this be strong enough ? whats the diameter of the sealing face,are they exactly 17in or is there some clearance ? whats the acceptable run out on a wheel ? I can get both sides running dead true after machining but if they need heat treatment after machining I might have to remachine them I don't think they'll distort that much , reckon on abt .005 / .010 ( .012 / .25mm ) would that be too much ? I'm going to hopefully make a small rear wheel in a couple of weeks to see what it looks like Any help would be greatly appreciated Thanks Not wanting to appear smug or anything, but the fact ouy are asking these questions means you don't enough knowledge of wheels to be in position o make them Your life depends upon them, so as said above leave it to the pro's By all means make 'em as demonstrations of the machines capability, but don't use them Without FEA analysis you will have no idea if they are strong enough, only through trial and error, and if they are too weak then......Well look at what happened to Robert Dunlop when his rear wheel collapsed at the IOM Link to comment Share on other sites More sharing options...
2 smokes 4 ever Posted July 6, 2009 Report Share Posted July 6, 2009 *deleted* - double post Link to comment Share on other sites More sharing options...
paul8899 Posted July 6, 2009 Author Report Share Posted July 6, 2009 I was only asking advice to see if people knew about the run out/rim diameter etc . As far as the strength etc is concerned I'm pretty sure that the design of the wheels would be good enough I'm only saying this because of the way standard rims can get damaged Anyway got a quote today for 2 billets of 7075 and L168 , 19" square x 6.5" and 4" the 7075 was £7 per kilo and the 168 was £5.50 kilo . The rear wheel billet would roughly be about 110kgs and unfortuantly it can't be hidden in another order gonna knock up a set of 5pw yokes instead Link to comment Share on other sites More sharing options...
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