pedromorgan
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| posted on 31/5/05 at 09:30 AM |
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this is a serious question
although it may not sound like it!
has anybody considered bolting a plank of wood to the bottom of their locost to improve tortional strength?
peter
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JoelP
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| posted on 31/5/05 at 09:57 AM |
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most wood would be too flexible to make any difference, even good ply. How thick were you thinking and what material? it would, however, be good to
prevent the car scraping on stuff, F1 style!
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nick205
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| posted on 31/5/05 at 10:08 AM |
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Like Joel says, can you expand a bit more on what you have in mind?
Nick
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pedromorgan
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| posted on 31/5/05 at 10:09 AM |
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i was thinking about 1 inch oak about 10 inches wide. it would add a good 20-30kg's but is seasoned correctly it would be incredibly stiff.
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Peteff
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| posted on 31/5/05 at 10:18 AM |
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Make a nice shelf with it and put some more metal in the chassis if you're worried about flex. There are lots of standard chassis on the road
and they've not turned into bananas yet.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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nick205
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| posted on 31/5/05 at 10:19 AM |
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I suspect you could achieve better results for less weight by building in more chassis tubes (steel).
Also wouldn't the wood eventually absorb moisture and hold it next to the steel chassis or ally floor, speeding up the inevitable corrosion
process?
Just my thoughts!
Nick
PS - how much would a chunk of Oak like that cost?
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pedromorgan
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| posted on 31/5/05 at 10:19 AM |
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no i havent had any problems. i havent actually started building it yet but i know others have noted that the book chassis is not fully triangulated
and i dont believe it can be as there is an engine in the way.
i want to do a book chassis and put morgan styly bodywork on it with full length running boards in a nice BR green or maroon. so performance is not
really the greatest of issues but ride comfort and safty make up for it.
peter
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pedromorgan
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| posted on 31/5/05 at 10:21 AM |
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oak is sold but the square food so £20 per sq foot 8 foot by 1 foot = £200
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Peteff
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| posted on 31/5/05 at 10:29 AM |
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£200
That much would build you the chassis, you'd think of doubling the price for the dubious benefit of bolting a plank to it?
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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pedromorgan
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| posted on 31/5/05 at 11:25 AM |
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well if you think about it. people are always going on about carbon fibre for strength. all carbon fobre is is synthethic wood. the sings on wodden
kit planes are often strong enough for one side to be bolted down and a person to walk along the other side in mid air. i think there would be
conciderable benifits to this idea but i dont know if it would be a better idea than doubling up a few of the pipes.
peter
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nick205
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| posted on 31/5/05 at 11:29 AM |
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IMHO a the plank would be better cut in 2 and made into a nice coffee table top.
Pedro - you say you're planning a locost with morgan style bodywork. Is it the Morgan connection that got you thinking about using wood?
I'm sure I remember reading that Morgan built their chassis out of wood somewhere.
Also you should look at Steve Gusterson's build as he is doing something very similar.
Nick
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pedromorgan
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| posted on 31/5/05 at 11:37 AM |
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it is partly the morgan connection that got me thinking seriously about it. but i remember there was a programme on telly about 5 years ago about
someone building a plane in 30 days and almost the entire plane was built from plywood and fabric skinned. they were constantly doing things to
demonstrate how strong it was. i know a wodden geodesic framework would be incredibly strong. i just have never seen a car made of wood before. howard
hughes made the spruce goose from plywood.
not on this car but on my next one i would like to cover alot of the body with veneer, especially the boot to give it a 'riva powerboat'
look.
peter
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ned
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| posted on 31/5/05 at 11:54 AM |
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lookup locust and chitty chitty bang bang for cars made of wood 
beware, I've got yellow skin
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pedromorgan
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| posted on 31/5/05 at 11:59 AM |
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i knew somebody was going to bring up chitty!! i didnt know about the locust pages though. thanks for that one.
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DaveFJ
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| posted on 31/5/05 at 12:03 PM |
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if used in the correct way Balsa is one of the strongest hardwoods available. It is actually used in the construction of some sky scrappers !!
Dave
"In Support of Help the Heroes" - Always
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craig1410
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| posted on 31/5/05 at 12:10 PM |
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I know F1 cars have a "plank" under the car but I'm pretty sure it ain't made of wood!!!
Cheers,
Craig.
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DaveFJ
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| posted on 31/5/05 at 12:15 PM |
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quote:
Originally posted by craig1410
I know F1 cars have a "plank" under the car but I'm pretty sure it ain't made of wood!!!
Cheers,
Craig.
Actually it is..... it is there to prevent them from lowering the car too far . at the end of the race the srutineers inspect the plank to ensure
not too much has been worn away during the race......
Dave
"In Support of Help the Heroes" - Always
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Bob C
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| posted on 31/5/05 at 12:15 PM |
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Sure wood's good stuff but a plank is the wrong shape. If you put one end of the said plank in a vice & tried to twist the other end by hand
you'd easily get several degrees of twist into it. You're aiming for several THOUSAND ft lbs per degree so it's one or two orders of
magnitude away from helping! It's also isotropic & variable. I'm going to stay with iron. BTW the wood frame in Morgans is a frame for
the bodywork AFAIK, not the main chassis.
Bob C
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pedromorgan
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| posted on 31/5/05 at 12:18 PM |
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i think it is made of wood actually. it is not structural though it is regulatory. it was brought in buy the FIA to stop the cars running too low. it
is measured after the race and if it has worn down too much (i think it starts at 12mm think and i think, it has to be more than 8mm by the end of the
race). then he is disqualified. i think it happened a couple of times when it was first brought in but i havent heard anything recently. i tink it was
one of the 'Senna' modifications.
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pedromorgan
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| posted on 31/5/05 at 12:25 PM |
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"The Morgan car has always been built around an ash-frame , and a steel chassis. The new Aero 8 also has an ash frame. This gives unique
strength, flexibility and surprisingly, research showed that the frame made the car safer on impact tests. "
from morgan web site
i think the point is that the ash body framework takes a large portion of the total load.
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nicksertis
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| posted on 31/5/05 at 01:07 PM |
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If you're after some more rigidity in the frame, I think aussie builders need to modify their chassis to get it to comply with stricter
guidelines there? Might be worth having a look at the Australian yahoo forum and see what solutions they have come up with.
Cheers,
Nick
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James
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| posted on 31/5/05 at 01:40 PM |
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This thread's been here for 4 hours and no-one's mentioned Cymtrics yet! 
Pedro, forget wood in this application. Search for the posts by Cymtrics whose done an FEA study of the chassis and has published plans of how to
double the torsional stiffness of the chassis for minimal weight gain.
As for the plank in F1. Wood is a little too kind a term for it- it's plywood I believe. A high density resin/wood mixture.
Some may remember that Schumey had a little trouble with his in about 2001.
Cheers,
James
[Edited on 31/5/05 by James]
[Edited on 1/6/05 by James]
------------------------------------------------------------------------------------------------------------
"The fight is won or lost far away from witnesses, behind the lines, in the gym and out there on the road, long before I dance under those lights."
- Muhammad Ali
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theconrodkid
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| posted on 31/5/05 at 01:55 PM |
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(murray walker voice on)and shoey is in the pits,he,s got woodworm and the mechanics are searching for the cuprinol...oh no its termites
who cares who wins
pass the pork pies
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DaveFJ
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| posted on 31/5/05 at 02:04 PM |
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Just to be a sad geek - again.....
quote:
3.13 Skid block:
3.13.1 Beneath the surface formed by all parts lying on the reference plane, a rectangular skid block, with a 50mm radius (+/-2mm) on each front
corner, must be fitted. This skid block may comprise more than one piece but must:
a) extend longitudinally from a point lying 330mm behind the front wheel centre line to the centre line of the rear wheels.
b) be made from an homogeneous material with a specific gravity between 1.3 and 1.45.
c) have a width of 300mm with a tolerance of +/- 2mm.
d) have a thickness of 10mm with a tolerance of +/- 1mm.
e) have a uniform thickness when new.
f) have no holes or cut outs other than those necessary to fit the fasteners permitted by 3.13.2 or those holes specifically mentioned in g) below.
g) have seven precisely placed holes the positions of which are detailed in Drawing 1. In order to establish the conformity of the skid block after
use, its thickness will only be measured in the four 50mm diameter holes and the two forward 80mm diameter holes.
Four further 10 mm diameter holes are permitted provided their sole purpose is to allow access to the bolts which secure the Accident Data Recorder to
the survival cell.
h) be fixed symmetrically about the centre line of the car in such a way that no air may pass between it and the surface formed by the parts lying on
the reference plane.
3.13.2 Fasteners used to attach the skid block to the car must:
a) have a total area no greater than 40000mm² when viewed from directly beneath the car ;
b) be no greater than 2000mm² in area individually when viewed from directly beneath the car ;
c) be fitted in order that their entire lower surfaces are visible from directly beneath the car.
When the skid block is new, ten of the fasteners may be flush with it's lower surface but the remainder may be no more than 8mm below the
reference plane.
3.13.3 The lower edge of the periphery of the skid block may be chamfered at an angle of 30° to a depth of 8mm, the trailing edge however may be
chamfered over a distance of 200mm to a depth of 8mm.
Dave
"In Support of Help the Heroes" - Always
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britishtrident
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| posted on 31/5/05 at 04:38 PM |
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quote:
Originally posted by pedromorgan
although it may not sound like it!
has anybody considered bolting a plank of wood to the bottom of their locost to improve tortional strength?
peter
What matters is torsional stiffness not strength and a plank of wood oak of the diminsension mentiond isn't very stiff in torsion.
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