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Plans 2 Build R1 Rear Engine Subframe?


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#31 SukiDawg

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Posted 26 September 2009 - 10:59 AM

I am a design engineer by trade for a large Engineering company in Leeds and having access to 2D (AutoCAD and some rubbish software called Medusa) and 3D (Rubbish Inventor and outstanding Uni-Graphics aka NX) software is a waste of time. To benefit from it you would need a model of a mini and the engine to start with. By the time these have been modelled you could have produced the space frame yourself. It is simply a case of trial and error in your garage.


I really don't agree sorry! I am also a professional designer, and I use NX, and I have a model of a shell etc which is being used for my RWD project (see other thread in this section). If you believe you can get a "better" result with trial and error in an existing shell than you can from design in the computer - assuming you are competent with the software - then I certainly wouldn't want you on my team! Sorry to say it, but proper engineering does not have to stay in the office.

My engine and shell models did take a reasonable amount of time to produce, but now I have them the ease with which different permutations and arrangements can be tried and visualised far far outweighs the time spent modelling. Too many people go flying into these projects, chop up a good shell, and then fail because they have created a load of problems at the beginning which they then can't easily solve later on.

Its true to say that not everyone has the skills and experience to create their own accurate CAD data, but to say its a complete waste of time really misses the point entirely.

#32 welshy

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Posted 30 September 2009 - 10:26 PM

SukiDawg,

I am sorry you disagree. I looked into modelling the mini shell but then i would have had to model the engine, the running gear, seats etc and this can not be done accurately with a tape measure and a 6" Rule. On complex shapes 3D modelling is only suitable for Order related engineering not reverse engineering unless you have CMM capability. You will struggle to find a CMM large enough to take a mini.

You will find no matter how much modelling you do, you will hit clashes all over the place. The latest techniques implemented by the automotive industries include a room consisting of a series of 3D projectors. These projectors project 3D scale models for the design engineers to spot clashes, issues which were not obvious on the initial model. These are models created by some of the top engineers in the world using software superior to NX like CATIA... even they get it wrong.

As for my NX experience i have enough to produce a representation of a mini shell using measurements from a tape and rule. Unfortunately i do not get to use NX on a daily basis at the moment and hopefully i won't get rusty as i am currently helping to role out SAP which is challenging to say the least.

I did produce a basic model of my role cage/space frame and proposed rear swing arm design but this produced a multitude of unforseen clashes. I treated it as time wasted but a lesson learnt.

Posted Image

Sorry you wouldn't want me in your team but i am a realist and i am sure as you continue to fire up your grinder you will have to enjoy some humble pie and i will bite my lip holding back the 'I told you so's'. However i don't think i will be given the opportunity to bite my lip as like any engineering shopfloor i am sure i will not hear of any clashes as the only feedback we get is on things WE have done wrong from a design point of view.

MickyH just go for it but remember measure twice, cut once. If in doubt give it a clout... or you may want to go for the if in doubt ask before the clout.
Before you decide wether a model is time well spent you may want to consider...Alec Issigonis didn't have 3D modelling capability and he didn't do too bad, infact i read somewhere that his iconic creation was in fact produced on fag packets which was manufactured with a trial and error hands on approach. Similar to what we are doing.

Anyhow, good luck to you both and SujiDawg make sure you take a couple of nights from modelling to read the IVA as it is one B***ch of a document to comply with.

Ben

PS Impressive Models.


I am a design engineer by trade for a large Engineering company in Leeds and having access to 2D (AutoCAD and some rubbish software called Medusa) and 3D (Rubbish Inventor and outstanding Uni-Graphics aka NX) software is a waste of time. To benefit from it you would need a model of a mini and the engine to start with. By the time these have been modelled you could have produced the space frame yourself. It is simply a case of trial and error in your garage.


I really don't agree sorry! I am also a professional designer, and I use NX, and I have a model of a shell etc which is being used for my RWD project (see other thread in this section). If you believe you can get a "better" result with trial and error in an existing shell than you can from design in the computer - assuming you are competent with the software - then I certainly wouldn't want you on my team! Sorry to say it, but proper engineering does not have to stay in the office.

My engine and shell models did take a reasonable amount of time to produce, but now I have them the ease with which different permutations and arrangements can be tried and visualised far far outweighs the time spent modelling. Too many people go flying into these projects, chop up a good shell, and then fail because they have created a load of problems at the beginning which they then can't easily solve later on.

Its true to say that not everyone has the skills and experience to create their own accurate CAD data, but to say its a complete waste of time really misses the point entirely.


Edited by welshy, 30 September 2009 - 10:37 PM.


#33 daza12165

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Posted 30 November 2009 - 02:19 PM

hi, i was wondering if anyone has built there own framework for an r1 engine to save costs and if they have any plans of this.
thanks mike



hi mate im planing the same as u and building my own, i dont mind sharing any info i have with u if u share with me DAZ

#34 SukiDawg

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Posted 30 November 2009 - 03:32 PM

SukiDawg,

I am sorry you disagree. I looked into modelling the mini shell but then i would have had to model the engine, the running gear, seats etc and this can not be done accurately with a tape measure and a 6" Rule. On complex shapes 3D modelling is only suitable for Order related engineering not reverse engineering unless you have CMM capability. You will struggle to find a CMM large enough to take a mini.

You will find no matter how much modelling you do, you will hit clashes all over the place. The latest techniques implemented by the automotive industries include a room consisting of a series of 3D projectors. These projectors project 3D scale models for the design engineers to spot clashes, issues which were not obvious on the initial model. These are models created by some of the top engineers in the world using software superior to NX like CATIA... even they get it wrong.

As for my NX experience i have enough to produce a representation of a mini shell using measurements from a tape and rule. Unfortunately i do not get to use NX on a daily basis at the moment and hopefully i won't get rusty as i am currently helping to role out SAP which is challenging to say the least.

I did produce a basic model of my role cage/space frame and proposed rear swing arm design but this produced a multitude of unforseen clashes. I treated it as time wasted but a lesson learnt.

Posted Image

Sorry you wouldn't want me in your team but i am a realist and i am sure as you continue to fire up your grinder you will have to enjoy some humble pie and i will bite my lip holding back the 'I told you so's'. However i don't think i will be given the opportunity to bite my lip as like any engineering shopfloor i am sure i will not hear of any clashes as the only feedback we get is on things WE have done wrong from a design point of view.

MickyH just go for it but remember measure twice, cut once. If in doubt give it a clout... or you may want to go for the if in doubt ask before the clout.
Before you decide wether a model is time well spent you may want to consider...Alec Issigonis didn't have 3D modelling capability and he didn't do too bad, infact i read somewhere that his iconic creation was in fact produced on fag packets which was manufactured with a trial and error hands on approach. Similar to what we are doing.

Anyhow, good luck to you both and SujiDawg make sure you take a couple of nights from modelling to read the IVA as it is one B***ch of a document to comply with.

Ben

PS Impressive Models.


I just read all that for the first time - must have missed it before. Obviously we are not going to agree, but let me say what I think now I've read it, and you can choose to ignore it as nonsense or not as you see fit. :kiss:*

You don't need CMM to accurately model existing parts at all, a surface plate, height gauge, knowledge of measuring techniques and intelligence gets you there. It doesn't need to be micron perfect to develop a concept, and I would not be foolish enough to cut metal straight off the tube - there is always a verification step when translating the design to a fabricated reality. If you really study a mini shell you will realise the floorpan, bulkheads etc are not fully 3D surfaces at all - and therefore perfectly possible to model accurately without any 3D scanning technology. Carefully take your measurements, more than once, and translate to the model. The statements about measuring twice apply to the model production just the same as they would to cutting material in the workshop. If you can cut something to the right size by measuring the shell you can also model that same shell accurately.

OK, proper 3D surfacing you will struggle with - but as a mini shell was designed before the technology you speak of existed it doesn't apply - as you kind of alluded to....

Also as an aside, you would not struggle to find a CMM large enough for a mini shell by the way if you work in the right industry - they exist in a couple of my client's factories for a start! Where you would struggle is getting one long enough as a favour, or at an affordable cost to get useful data from it in the time available.

CATIA isn't "superior" to NX chap. Its equivalent (I'm a proficient user of both, 12+ years on UG/NX and 6 years Catia), and they both have their strengths and weaknesses. Looking just at F1 teams, you have McLaren, Ferrari, and a couple of others on Catia, and Red Bull, Brawn, Williams (converts for 2010 season) on NX. Catia does surfacing well, UG has an excellent CAM module. Its horses for courses. I chose NX for the mini because I prefer it and am more comfortable with it day to day.

And these "top engineers in the world" that can't avoid a mulititude of clashes even with fully modelled designs might need to re-consider how they class themselves...... :D

I honestly don't understand how you can discover clashes on CAd which either wouldn't apply in the real world or aren't relavent. I just don't think you know how to use it! Sorry.....

#35 minifan666

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Posted 15 June 2011 - 01:05 AM

hello,
so what happens here? What is next? I veus well do the same thing with a mini, but I still looking for the car (they are rare in our country) and already my plan is to build a 6-point rollbar I still seek information and plans, if any (is to make a mini R1, rear engine)




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