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Technical & Reference Section => Tech and Restoration => Topic started by: oldschoolace on August 20, 2011, 11:42 AM
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Does anyone have an idea as to costs for cnc milling work? Is it priced on a time basis and what sort of money would you be looking at to get something like a spider made up?
Cheers all :daumenhoch:
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Been 2 c somebody this morning along similar lines. Looking at shit loads 4 a 1 off :'(
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Been 2 c somebody this morning along similar lines. Looking at shit loads 4 a 1 off :'(
Damn it i knew that was going to be the answer :( i did think about finding some oldtimer engineering type with milling gear but i think one element of what i want to do will need cnc'ing as its a bit fiddly
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where are you in the country?
if west london - heathrow
wellington engineering - opposite the hayes bmx track almost, 20 cnc machines I paid £300 for some custom aluminium car/van hubs
if in south west london
mollarts engineering - 20 plus cnc machines -specialist line boring drill manufacturer - i paid £440 for a pair of hubs
chessington
for one offs and the like look on here,
http://www.nsra.org.uk/newforum/forumdisplay.php's=0e8cebec76d352171f7ecc8dc3539c5e&f=6
there is a chap who laser cuts flat stuff forget his name - minimum charge for a small flat item is about 30 slaps
or east london
trevor dorrington - race car fab - no cnc, but milling machinery.
01268 777269
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Cheers Steve, in Manchester unfortunatly but the part i am looking to make isnt large so location isnt that important. It is nice to call in these places though and get to know peeps.
As general info for anyone northern there is a cracking place called general utilities in stockport who do laser, plasma and waterjet cutting. They are very reasonable and dont mind doing one off stuff. some of there waterjet samples through 2 inch steel are amazing. They had a bicycle around 5 inch long with spokes at around 1mm wide cut through the 2 inch stuff! :shocked:
Hey we should have a thread for stuff like this! :daumenhoch:
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For a one off you’d be better off going to a local machinist who would make you one providing you have one he can copy or a set of drawings he can work from.
A CNC miller needs an “NC file” which is normally generated from either a 2D or 3D CAD file (DWG/DXF) if the company has to generate a CAD file there is sometimes an associated cost for a one off.
The main disadvantage with CNC machines for one off’s is the set up time and CAD file/model generation time and a skilled machinist using a conventional miller will be able to produce as good if not better and cheaper finished part.
We would charge £40 per hour + materials for “knife and fork” jobs
When we had an engineering company we’d do the “knife and fork” jobs on the conventional machines and anything that had tight tolerances/multiple/repetitive cuts would be CNC
If the spider is flat (Like a tuf neck power disc) laser cutting would be a better option normally there minimum charge would be £50 and you would get around 10-12 disc’s
I so miss making CAD models and playing with big boys tools :'(
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I bet you do Peter, i would love to have a go at all that stuff. I'm a woodman myself so occasionally get to play with a cnc but metalworking could be ace!!
Am actually looking to get a stem made. I blame that american hotrod programme, it always looks so easy on there! >:(
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if you want a one off think £35 an hour for cad work,same for programming,same for set up and machining,plus material.
I think £200.00 could get you a one off spider :daumenhoch:
Lazer cutting a powerdisc and machining could be a lot cheaper. :daumenhoch:
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I'm pretty good on cad gear as i use it for work sometimes, just need a nice man with a machine :daumenhoch:
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A stem would take multiple passes and cuts plus you would also need someone with a lathe as well for the stem shaft
Material wise you'd need a good general grade like 6061 (T6) or if you can find an off cut go for 7075 better strength properties but more expensive and harder to find where as 6061 is cheap and every bugger stocks it
Also consider head treatment may be needed as well to relive the metal stresses associated with machining as well as help with tensile strength................I could get really boring and go into FEA (Finite Element Analysis) but to be fair even I fall asleep discussing that.....
As for the shaft Cromo all the way and this should be threaded into the stem head using a “force fit” I cannot remember the correct terminology for it
If I was making one I would also knurl the shaft along its length...........
I’d looked at making one (a one off of my design) and even with me generating the CAD model (which I still have) the costs would be in excess of £150 but then I suppose if I’d looked at making one to a normal specification with less cuts and cheaper materials I could get it down to £70 ish
If I ever get a spare Saturday I would love to go to my old place and make one I worked out it would take about three hours for me
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Sounds like you know your stuff Peter, i may have to pick your brains at some point :daumenhoch: The stem idea i have is pretty straighforward apart from one piece so machining would be minimal hopefully. I did wonder about materials but from what little i do know about metals there are more grades than you can shake a stick at.
Would a plastic stem be madness? - in one of the harder plastics like tufnol (http://pistonheads.com/inc/images/scratchchin.gif)
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Short answer is NO
Medium length answer is:
Although composites have, in some instances better liner strength than traditional materials you need to factor in “Product Life Cycle” this covers such aspects as stresses both cycled (pull/push) and twisting. Also these materials have a limited life....the first time its stressed it will retain 100% of its strength the next time it might me 95% etc etc until SNAP !!!
Products are designed with in parameters for example certain F1 parts are designed to last a race because weight/performance is a more important design factor than longevity and therefore engineered/designed accordingly.
I’m not too good on composites but I would think that they would not react that well to this type of application because of the non standard loads this type of part would experience over its life span............not to mention crashed/bumps/scrapes etc etc
I know you can get MTB stems/bars made of carbon fibre but there are use/weight limitations
I have a 3D CAD package (Solidworks) with an FEA package (Solidworks Simulation) and I/we used to design some really cool stuff and it’s amazing how a little tweak here and there (not to mention material changes which then can impact on the design) and can make such a difference and to “Joe public” they would never notice a design change
http://en.wikipedia.org/wiki/Finite_element_method
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Dude do you stil work in this field? if not thats some wasted talent right there! :coolsmiley:
How about 3d printing a prototype then casting? I have just found an ace place literaly next door to my workshop that does laser cutting and 3d printing FOR FREE!! :shocked:
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On I sold up a few years back but I still have a play with designing stuff plus I sometimes help out with the machining/assembly processes
Once you’ve made your 3D prototype then you could get it cast.....however the for a stem this would be a longer more expensive process:
Make 3D Model
Get a Foundry to modify Model with feeder necks/run offs
The model would have to be cast using sand/resin to make the mold (a die would cost £1000’s)
They would probably use LM25 as this has the best machining properties and is a good “general” alloy to die cast with
The part would then need to go though the machining process discussed before
The best option would be to machine a stem from “bar stock” because with gravity casting the crystals of the aluminium are not aligned as well as say extruded alloy
I’m not going to bore you with crystal alignment or mechanical properties of aluminium
One of the clients we had was a non-ferrous foundry in Sheffield and I did 100’s of designs/produce analysis for them
Designs are normally a trade off between cost/function
Example: Rolex Watches are function/feature over cost Casio Watches are cost over function/feature
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Oh and with any design/product you have to consider material/design harmonics :smitten:
Classic example of bad design harmonics would be the Millennium Bridge (London) :idiot2:
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Oh and with any design/product you have to consider material/design harmonics :smitten:
Classic example of bad design harmonics would be the Millennium Bridge (London) :idiot2:
Or the b of the bang ;)
Hate the twunk who designed that and now they have give him the task of redesigning the routemaster bus ::)
Thanks for the advice :daumenhoch:
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been reading this with interest (even though I don't understand a lot of it ;D)
but I think steve should show us his hubs...
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If I ever win the lottery, Peter J is going to design me some Tuff style wheels that will take a cassette driver :crazy2:
Imagine tuff wheels polished to bling with a 9t driver and a 14mm axle :shocked:
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If I ever win the lottery, Peter J is going to design me some Tuff style wheels that will take a cassette driver :crazy2:
Imagine tuff wheels polished to bling with a 9t driver and a 14mm axle :shocked:
I can imagine getting a hernia trying to do a bunny hop ;D
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If I ever win the lottery, Peter J is going to design me some Tuff style wheels that will take a cassette driver :crazy2:
Imagine tuff wheels polished to bling with a 9t driver and a 14mm axle :shocked:
What like this ;)
http://bmxmuseum.com/forums/viewtopic.php?id=348786
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I’ve worked on everything redesigning the torsion bar on the mk1 Audi TT............bloody Germans cannot design owt :uglystupid2: !!!!!! to a mechanical “matrimonial aid” that pleasures the female of our species........you wouldn’t believe what they are will to pay for a bespoke piece to kit :shocked:
And everything in between !!!
:daumenhoch:
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I’ve worked on everything redesigning the torsion bar on the mk1 Audi TT............bloody Germans cannot design owt :uglystupid2: !!!!!! to a mechanical “matrimonial aid” that pleasures the female of our species........you wouldn’t believe what they are will to pay for a bespoke piece to kit :shocked:
And everything in between !!!
:daumenhoch:
(http://www.pistonheads.com/inc/images/bow.gif) we are not worthy
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If I ever win the lottery, Peter J is going to design me some Tuff style wheels that will take a cassette driver :crazy2:
Imagine tuff wheels polished to bling with a 9t driver and a 14mm axle :shocked:
What like this ;)
http://bmxmuseum.com/forums/viewtopic.php?id=348786
Like that but blinged, Complete ali wheel CNC machined and polished like on American Chopper 8)
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like this?
(http://farm1.static.flickr.com/46/134385415_a51854e9c9_z.jpg?zz=1)
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My first powerdisc..............I had the discs laser cut with the correct PCD to accept a Sugino chainwheel and I programmed the CNC to do the logo............Hummmm pies
(http://www.radbmx.co.uk/archive/albums/a253/the1carper/P1010166.jpg)
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3D CAD model of the stem.............with cheeky logo :coolsmiley:
(http://www.radbmx.co.uk/archive/albums/a253/the1carper/SquareHeadwithStem.jpg)
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Have another (http://www.pistonheads.com/inc/images/bow.gif)
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3D CAD model of the stem.............with cheeky logo :coolsmiley:
(http://www.radbmx.co.uk/archive/albums/a253/the1carper/SquareHeadwithStem.jpg)
they gonna be available at MK12?
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like this?
(http://farm1.static.flickr.com/46/134385415_a51854e9c9_z.jpg?zz=1)
Yep, But I want the whole bike blinged, Chrome and polished :coolsmiley:
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pete your the bollox mate..... could you make me a threadless 1 1/8" GT mallet stem :-* :-* :-*
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Costa for you I'd do anything........................such a beautiful man :smitten:
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Costa for you I'd do anything........................such a beautiful man :smitten:
gay lord :bondage: ^"^
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Costa a sexy beast like you would turn any man :smitten:
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Costa a sexy beast like you would turn any man :smitten:
:-[
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Pukka Pies :2funny: :2funny: :2funny: :2funny: Brill :daumenhoch:
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oh
they were car/van ubs
to fit porsche 996 turbo discs and calipers onto a split screen volkswagem.
not push bikes.
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Peter, rather then do a whole stem could you not just engrave/modify a stem? I've got a mid school Odyssey stem and it is basicly a block with a small amount of etching that could be eradicated.
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What do you want doing?
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What do you want doing?
I dont want anything doing, Just Peter was talking about doing a stem and saying how much a one off would be? I was just thinking that you could take a mass produced product that is pretty boring and customise it with some engraving.
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i meant oldschoolace :LolLolLolLol:
spiders are probably very easy for me to sort.
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i meant oldschoolace :LolLolLolLol:
spiders are probably very easy for me to sort.
It was a stem i was thinking of bringing to life ;)
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how did it die?
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how did it die?
I didnt really, it was never born to my knowledge but if you had one it would be quite special ;)