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• #2
can you 3D print steez?
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• #3
Cool, interested to see how it works.. can you take time lapse vids of it building them?
How do you know whether it'll be strong enough?
also what are the approximate costs of this endeavour?
Thanks!
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• #4
Cool, interested to see how it works.. can you take time lapse vids of it building them?
the printer only works in an inert enviroment so its actually in an airtight case, im not sure how a camera would cope. also, i think the laser point is so bright it would damage the camera sensor
How do you know whether it'll be strong enough?
Im an FEA engineer, so thats my first port of call. unfortunately, i dont have enough time to do it properlly, so its gunna have a lot of guessing. im probably just going to make a part that weighs a specific amount and make sure it doesnt have any stress intensities.
also what are the approximate costs of this endeavour?
printing stuff like this costs mad dollar. fortunately, im not paying ;)
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• #5
In Australia we have been collaborating to get a few things printed.
Stem caps and now bar end plugs. In plastic, non-load bearing and cosmetic only.Australian Tube Products Stem Cap Project
interested to see how strong the items are.
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• #6
ok, so when i said i was in a hurry, i wasnt kidding!
just finished the concept font hub:
were talking about laser sintered flanges mounted to a carbon tube (like a chub hub). itll also have a carbon fiber axel and Ti bolts.
I was actually thinking of making the flanges hollow and really thick, just to make them look weird.
the cool thing about the model i made is its parameterised. i can change any dimension within the model by changing the parameter in my script, then rebuilding which takes a few seconds.
a few things i decided on: spoke PCD is 73mm, like the mack superlights. that way, when this hub breaks, i can replace it with a mack without having to buy new spokes. ive also based it around the same bearings as the mack super lights use.
next step in the process will be calculating the weight, and stress analysis. this is a job for tomorrow evening though.
if anyone has any input, id really appreciate hearing it. you guys probably know more about htis than me ;)
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• #7
Subbed, this is cool
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• #8
Nice project.
Are the flanges going to be made out of steel then?
May I just say (and this is without knowing anything about engineering/material stress/etc) that the flanges do not seem beefy enough. Like the cutouts are too big and might need more material between spoke holes.
Aesthetically I prefer round flanges, but that is just me.
Looking forward to the final result. -
• #10
Steel won't be as rigid as aluminium so flange flex might actually be a thing.
How are you planning to bond the flanges to the carbon tube?
Will the threaded part for the cog/lockring be part of the flanges or separate?
The bonding and carbon tube need to be able to transfer some torque to the NDS flange, that's why I'm a bit sceptical to composite hubs.
imho. -
• #11
Purely from looking at it I reckon you need some more meat in there.
Don't suppose you have access to any of the new design optimisation packages that work out the most efficient (strength to material) design for you? Never seen it on anything circular though only stuff like struts.
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• #12
Steel won't be as rigid as aluminium so flange flex might actually be a thing
Steel is about 3x stiffer than aluminium so a more slender flange (euf?) will be about right.
This is an interesting project, I know this is used for repairs by a lot of the big aerospace manufacturers but often with post-machining to get the right surface finish. As you have more design freedom I'd try to come up with a design that couldn't be made by conventional means, how about a hollow flange (thin wall but wider cross-section)? -
• #13
Cool.
Can you print cog/lockring threads or do those need to be machined later?
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• #14
Ha nevermind.
Just reread the OP..Cool.
Make sure you post the results!
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• #15
talking about laser sintered flanges mounted to a carbon tube (like a chub hub)
Isn't the point of the chub hub that the huge body makes it really torsionally rigid to get better torque transfer to the NDS? Could you produce some sort of large diameter tube or webbing between the flanges?
Also, just to check, are the spoke holes in that drawing offset between the DS and NDS. It's diffiult to tell, but they look like they're lined up, which wouldn't work (although this isn't a problem if you can bond it to the centre tube in any rotational position).
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• #16
Hey guys, morning update!
First off, im going to make a top cap too. but i dont know what to put on it, if you come up with a good idea i might just make you one too! theres a seperate thread for this though, it can be found here:
https://www.lfgss.com/conversations/287504/
Im gunna run through a few questions about the hub.
First, its a front hub so im not too worried about torsion, im also updating the description to make it easier for others.
Second, the CAD model is just a representation of what it will look at, dont worry about stuff looking too thin at the moment.
Third, lets talk about that flange! the cut outs are huge leaving little material, but remember this is steel not ali so will be stiffer right off the bat. t
Also sharp eyes ffm, i had forgotten to rotate half of the hub when i mirrored it :P
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• #17
Make a lattice style top cap with a pattern similar to that of your hub flanges.
That weight weenie drillium style. You don't see too many of those. -
• #18
I'm not an engineer so all the following may be bollocks. Since the spokes run inward from the flange to the rim and are under tension, presumably the load they extert is not perpendicular to the hub axle. Could you improve the design of the flange by making it slightly cone-shaped so that it lies exactly in the plane of the spokes?
Edit: after all, rims have eyelets drilled off-centre so that the "point" at the flanges; why don't the flanges "point" at the rim?
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• #19
@ffm makes a good point.
For me the exciting aspect of this project is the ability to make something the doesn't follow the traditional 'rules' of hub manufacture. I understand you're on a tight time frame but it would be interesting to see some more conceptual thinking, and truly take advantage of the manufacturing process.
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• #20
For me the exciting aspect of this project is the ability to make something the doesn't follow the traditional 'rules' of hub manufacture. I understand you're on a tight time frame but it would be interesting to see some more conceptual thinking, and truly take advantage of the manufacturing process.
Precisely! This isn't mass-production.
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• #21
For me the exciting aspect of this project is the ability to make something the doesn't follow the traditional 'rules' of hub manufacture
exactly what i was thinking, but this is steel, its heavy as. im finding it hard to think of something that is different, and isnt too heavy. on the rear hub, i might consider adding a lattice between the flanges. can we think of anything that pushes the boat out a bit?
Could you improve the design of the flange by making it slightly cone-shaped so that it lies exactly in the plane of the spokes?
correct, but its a massive ball ache to implement into my model. ill mull it over and see what i can do.
heres the hub cut in half so you can have a look at the geometry.
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• #22
Do you think you may need a small lip to ensure the bearing remains properly located?
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• #23
there should be a l;ip, but ive managed to choose parameters which hides it! good catch, ill fiddle with it til its back. i was also thinking about putting a race on the carbon axle so that it fits snug wiht the bearings.
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• #24
It doesn't look as if there's anything to keep the flange/body section in place, as in it can freely move side to side...
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• #25
Does it have to be solid and 'round'? I haven't really thought about this much but could you do away with the carbon body and print the whole thing? Some kind of lattice body? Faceted body? A group of rods?
This is the situation:
1) I want a set of mack hubs but cant afford it
2) I have access to a fancy 3D printer
BUT
1) The printer is set to stainless steel, not aluminium or titanium (BALLS)
2) I have to sort this out in sub 2 weeks
I was thinking of printing a set of hubs. but i can basically print anything that is small (top cap, bar ends, the works).
The printer is incredibly accurate, and can print extremely small/complex parts. Components can have structures that have sub millimeter thicknesses. it can also print an interference fit without further machining being required. in fact, it can print threads.
This project may get derailed for various reasons, but i was kinda thinking of keeping people posted on my extremely fast/botched design and progress :)