My Fmp In Collage

[Radfax]

Hey!

Well in collage today i was talking to my tutor about my Major Final Project in my course i am taking> The breif is extremely wide open and i have come up with the following idea and i would like to hear thoughts and hear your ideas ect.

As my MIG welding skills are getting better I have decided to design and make my own frame as you may have guessed from the topic title, I am planning on making a long and low mod. To be completely honest with you it doesnt need to be structuraly amazing because it doesnt need to be riden (although it will be) It just need to be some thing that stands out from the croud. i am planing on taking the main features like magura mounts (might even go for a vee) head tube and bottom bracket from a steal bike which i will borrow from some where. I want the frame to be extremely low and rather long as i am getting on for the 6ft+ mark now.

Apart from it being long and low i have no idea on what i want it to be like, I am thinking some thing slightly like the GU but with square tubing and some pretty extreme gussets.

Could anyone give me any advice or pointers on anything please as i would like to ride the frame after it is produced maybe take it on a london ride or some thing and show my master peice off.

So i would really like to know what you guys like in 20" frames, what atracts you to them, what makes you stop and stare at them and makes you say to yourself "Jesus christ i want one of them beasts!"

Thanks a lot guys, Tom

[Haz]

Got any designs or draughts? That's the first place to start, ideas of form will all ways helpat an early stage like this.

[Mr Motivator]

A frame I made;

Does it make you think, "I WANT ONE OF THOSE BEASTS!" ?

Bet it does-nt.

Draw it in CAD well, you can get away with not even making it, or just making a proto.

What course are u doing?

[JT!]

Wern't u trying to sell that frame for £90?

[Brian Bleech]

Have a look towards other areas of cycling and see if you can apply technologies/techniques to your trials frame that hasn’t been done before 

Take a look a the Eastern BMX frames in this months RIDE, Holes cut out and serated dropouts (so the wheel doesn’t move), also look at using spanish/mid bb – things like that would make me look twice

[Heatsink]

Some ideas to get you started:

Looks: If you're using square section why not think about the aesthetic and weight saving benefits of external butting (milling away material on the outside of the tube). Circular tubing is not easy to do this on, but flat sided tubes are. Also, compare different finishing processes such as painting, powder coating etc. Cost, effect, durability.

Weight: Careful design to make sure the weight doesn't turn out crazy high. Use a calculator or spreadsheet to add up the weights of all the tubing used (approx lengths). From the tubing geo you have the volume, and from the density (for steel 7.9 g/cm^3, 7900 kg/m^3, take your choice on units) then this gives you the weight. Do some research into the sorts of tubing geos used on other steel frames.

Design Calcs: A great opportunity for you get some proper design understanding and optimisation into your frame.

1. Look into calculating the stiffness of different tube geos, round versus square, to get an understanding for the effect on shape (distribution of mass) on the tube's stiffness ."Second Moment of Area". Just what is the best way to locate a given mass of tube (simply, compare the same cross-sectional area in different shapes) Search Wikipedia and the web for info on this sort of thing. Satisfy yourself that you know what the "Neutral Axis" of a tube means.
2. Also, research general principles of design and go back to basics (searching for info in a bike context goes to show that these principles are often forgotten) such as looking at the stress/displacement/stiffness equations for cantilevered beams etc. Where is the max stress, max displacement, and the equations showing all the important factors. -> Note the inverse cubed relationship between tubing length and stiffness.
3. Look up "Stress risers" and apply this to the stress regions at the 3 joints: Headtube, BB, seattube-seatstays-toptube junction. Think the effect of sudden geo change and maximising area to minimise stress.
4. Compile info on the relative mechanical properties of the steels at your disposal. Take into account processing requirements (to maximise material strength) such as the need (or not) for heat treating following welding.
5. Produce a cost estimation to complete the frame, contrasting different material options/suppliers

Project Plan: Why not produce a "Gantt chart" in Microsoft Project to catch all the tasks and resources (time/money/people) needed to build the frame? With a plan that you can continually update as you go, then there's more chance of you achieving what you want for the right money at the right time.

Steve

[Mr Motivator]

Wern't u trying to sell that frame for £90?

Why, you want it?

Heatsink knows his stuff Don't think that he is able to produce a "short post" though, ever

[Christophe']

Some ideas to get you started:

Looks: If you're using square section why not think about the aesthetic and weight saving benefits of external butting (milling away material on the outside of the tube). Circular tubing is not easy to do this on, but flat sided tubes are. Also, compare different finishing processes such as painting, powder coating etc. Cost, effect, durability.

Like Pace did

[Radfax]

Thanks a lot for the replies guys!

The course i am on at the moment is my first national diploma which i was taken out of school for. So far i have been designing with habitat and i have been with them for about 3 weeks now and i will have to find some where else to go in january. I am studying graphics design and i have been extremely drawn to the idea of making a trials frame. Next year i hope to complete this corse and aplly at KIAD and take place on a graphic design corse for the next 3 years and then i will see where i can go from there. I just need to get my grades in my GCSE's 4 C+ grades and one of them being in english.

I have not really sat down and thought to hard about the idea but for my last unit i designed and produced my own chair. it was a sun lounger which had incorperated the ideas of a rocking chair covered in zebra print material and it looked ace! I will try to get some pics up!

The collage i work in is a enginering collage (although the corse is run by KIAD) So i THINK i should have the privilages to use the welding stuff at the collage and get the frame built for me as long as i can provide sufficiant plans.

To be honest i am not entierly sure what i want the frame to look like apart from a long and low kind of thing, I will just go and have a read through your post steve! I will be back in a mo!

Thanks guys, Tom

[ogre]

When i was thinking about getting an iolo i was playing about with a few ideas for it. iether having an internal tentioner like on that onza with the funky chainstays or, having fixed dropouts and having a mount for a sprung tentioner that allowed me to run a longer chain so if i missed up the chain could go right up to the dropouts so no stress was put on my freewheel or chain (i'm shitscared of a chain snaps :$ ) and then having a block of steel along the dropout between the wheel and cranks with a section cut out for the chain to run through it.

[Radfax]

Humm that sounds like a great idea but seems a lot of hasle on the idea of runningthe chain through the chainstay idea, getting everything to the right size so everything lines up ect, you would also be weakenging the chainstays a lot i suppose. I like the idea of the intergrated tensioner, i used to have a DFX dragonfly with it (i think) and i dont suppose that it is to much of hard work making one, have a thich dropout and then dril and tap a thread in and hey presto you have a intergrated chain tensioner.

To be honest i dont know what people look for in bikes, i am looking ionto getting a GU soon and i have choosen it because its nice and long its got a bit of BB rise on it and it doesnt look to bad but what does the majority of the trials riding community like in bikes? high bb low bb what?! I am thinking of using some king of bmx bb so that BMX type 3 pc cranks can be used, like on daves new adamant. The locking idea on the old montys made me look twice and was a rpetty kool idea on the sides that it resulting in not having to fork out another £20 odd quid every other week for eating wall.

i used to have a bike when i was pretty young, it had run the brake cables through the top tube, and that made a few lads riding around (on them old giant "maritn" things) my area stop and look even though i was about 9 and now i see that Iolo has incoreperated this into one of his new 24" builds. I also really like the idea of having two top tubes like the evil imperials and Dunckan Cocks because thet definately made me stop think and eventually buy one.

the only problem i have at the moment is designing something thats really good and then being told that the techniques of the collage are not up to making it, although i doubt it.

[Heatsink]

There is plenty of scope for a custom chain tensioning method. If you're using it for singlespeed trials, I'd seriously consider not having the standard mech hanger set-up. Simplify things from a manufacturing point of view and also get a custom solution that will be optimised for trials use (max chain wrap, simplicity of tensioning related parts = low cost, weight reduction and tucked away from knocks)

Look at the tensioner mount that Leeson bikes use. The simple mounting tab positioned further up the chainstay allows a very small, simple and tucked away tensioning arm and all the optimised aspects mentioned above compared to running a singlespeed tensioning arm on a rear derailleur.

The rear brake mount area is another place you could think of some novel ideas. I've got some concepts in this area which I will hopefully be showing on an example frame after Xmas.

Steve

[trialsni]

instead of making a frame why not think of a trials training aid instead not too many of those about were as there are 100s of frame designs