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If you have the carbon axle as shown then at least one cup will have to come out of it every time you want to change the bearings

yup, pretty much, but the new hope hubs use the same system.

It's a sintering process this, isn't it? How does it affect the strength of the final material? Let's say ya boggo standard pressed mild steel for a flange is something like 500MPa in tension, what would this stuff come out like?

this is a really good question. in all honesty, i have no idea. i was chatting to our printing expert the other day, and he claimed the in plane material properties of sintered alloy, could actually surpass that of non-sintered alternatives. He explained why, but there were alot of words i didnt recognize.

really i should use reliable sources when choosing material properties to model with, but im going wiht this site for speed

https://www.stratasysdirect.com/blog/material-nuances-metal-3d-printing/

the simulations are on, heres the mesh:

theres going to be two flavors of simulation, first will be tensioning the spokes to 200kg, just to see how it reacts. the second will be taught spokes, and then a single spoke will be pulled until failure. this is quite unusual because its not realistic, however it is basically the worst case scenario, which is what im interested in.

these computations are pretty heavy so im running it through a small cluster, however, it still looks like itll at least take 10 hours.

when the results do come in, i can have a look at areas that are highly stressed, and those that arent. then material will be stripped away accordingly. unfortunately, this thing is currently HEAVY. the stainless steel parts alone are 180g, and its a front hub!

When I say offensive. I mean nothing that is a bit racy aswell. I think they probably would, but they wouldn't take me seriously ever again if I took it to them lol

I dont think the print centre will print anything that could be deemed offensive I'm afraid. Thats why the hed top cap doesn't have "suck my" on it either :(

no no, i have access to an awesome 3D printer. im going to try and sneak these through it ;)

Turns out HED wheels arent easy to draw in CAD. theres a small error on it, i might have a second go at it.

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.

I could rip off the HED. trispoke, then write "suck my HED." on it, one word for each spoke?

incidentally i dont own a HED wheelset ...

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.

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

Hey all, got a nice little competition here.

Im going to 3D print a custom top cap in the next few days. itll be stainless steel but not shiny, there will be a matt finish.

The problem is, im not very creative, and need help thinking of what to stick on top of it. Can you give me some ideas? If i choose your design, ill also make you one (or try to).

I cant print colour, but i can indent/raise stuff as needed. I can also add simple CAD sculptures to the top, like spikes, if you wanted a top cap that will rip your nut sack off when you go over the bars.

If my work notice "irregularities" in what goes through the printer, this will be derailed. really quick.

so far, this is my favourite top cap, and i think it would look cool if the skull was raised:

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 ;)

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 ;)

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 :)

for the wheels, you can get the price down if you build a set with kinlin rims.

kinlin XR 200 rim - 380g, £30 per rim!

http://dcrwheels.co.uk/products/rims/700c-rims/kinlin-xr200/

get a pair of novatek hubs and you could end up with a cheap light wheelset!

thats a good price for a S3. those things rock :)

I used to have a malum, such a sexy frame. If it was a bit bigger I would have this off you in a snap :)

stella come in pints, i needed to make sure it could hold three of them! plus i like beating women, just look at her frame!

So i have finally got round to sorting out my malum!

Specs:

Material -Steel
Weight - 1.4Kg
Volume - 1.7L (no messing around here)

This could actually be an improvement on the frame!

More images can be found here:
http://imgur.com/a/kNbBO

Currently seeing an Italian, my eyes have been opened to advanced pizzas, a few of my favourites:

goats cheese, tomato, bacon, plum

golden plum, almonds, whisky

chocolate, orange zest, clotted cream calzone.

next time we make some, ill be sure to take some photos :)

I do often look through NAFEMS, some of the stuff there is incredible. I might have solved my experience problem though, im currently looking at working with dassault systems and their living heart project (seriously cool FEA!):

http://www.3ds.com/products-services/simulia/solutions/life-sciences/the-living-heart-project

I didnt know FEA wasnt commonly used in the oil industry! I would have assumed anyone with that much money would just default to it. I guess as high performance computers become cheaper it will be adopted in more industries. Ill keep an eye out on this area because i would happily work in the industry.

Sorry for the late reply. My primary software package is Abaqus Explicit, both structural and FSI (coupled Eularian Lagrangian, no messing around!). I think a couple of groups do model their frames (specialized had a frame where the decal was actually the stress contours, again this was done in abaqus!), BUT i dont think its effective (probably making more enemies than job opportunities at this point...). Carbon fiber is a real pain to model (I should know, my girlfriend did her PhD on modelling carbon fiber, makes interesting dinner table talk...), especially thin walled stuff with complex geometries, like bike frames. You could say the material is orthotropic and simplify your model, but that is a massive limitation. Furthermore, i seriously doubt bicycle companies use FEA for robust design optimisation (my area), which could be used to make some light frames!

Having said that, CFD is commonly used to good effect. One of my old lecturers was actually contracted by the british olympic TT team to work out what the most aerodynamic bolt shape is for the wheels.

Hi all,

Im not really sure if this is a great place to put this but here we go.

I have just finished my PhD in advanced FEA/FEM. Currenltly Im waiting for my viva which has been delayed, fortunately I have been employed by the university part time. This means that I have a large amount of time and resources on my hands. I would like to make the most of this by increasing my design portfolio.

Using FEA, I can reveal the stresses/strains within bicycle components. this will allow you to compare different designs or conclude whether or not the part will fail.

FEA isnt commonly used in the bicycle industry, or at least not to the extent which i would like! This is because its incredibly expensive, both in software, hardware and employee salary. Fortunately I have unlimited (free, and legal) access to FEA software and a variety of computing clusters to crunch the numbers.

My primary objective here is to increase my design portfolio/gain experience, as a result I will construct and run small jobs for free. larger jobs, like full blown design optimisation, would require some compensation (ill accept shiny bike components) as it is so labor intensive.

I can supply my CV upon request.

Jon

pm sent

i wouldnt sell them! put them on a nice stand and stick in the middle of your table. hopefully you will have rim money in the future and then you can use them :)

was wondering if you could drill another 16 holes into them? ive been looking for some mach hubs, but im a bit fat for 16h :(