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#Post#: 6124--------------------------------------------------
Wooden chassis
DIR By: RhysN
Date: March 23, 2022, 1:38 am
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This car has done hundreds of miles, off road expeditions in NZ.
Chassis is from scaffold boards. One of Brian Smith's several
builds.
#Post#: 6125--------------------------------------------------
Re: Wooden chassis
DIR By: RhysN
Date: March 23, 2022, 1:40 am
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My Kim, somewhere here in the UK. Oak rails, wooden body tub,
clad in very thin alloy sheet stuck on with Evostick. Full size
car was my Peugeot.
#Post#: 6127--------------------------------------------------
Re: Wooden chassis
DIR By: David F-R
Date: March 23, 2022, 3:42 am
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Excellent start to the topic.
Oak for the chassis sides? I was wondering about some straight
grained pine. It's used extensively for structural work.
(Personally, I do have plenty of oak 'in stock' but \I was
thinking about what is readily available and cheap.)
#Post#: 6128--------------------------------------------------
Re: Wooden chassis
DIR By: synthpunk
Date: March 23, 2022, 4:16 am
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Swings and roundabouts?
There are few domestic hardwoods available that are as strong as
oak, it has excellent resistance to rot, but it does somewhat
lack flexibility. Ash and hickory are similarly long grained
(strong) timbers, but have better flex and shock resistance.
Which is why it’s good for hammer shafts. Sadly ash is getting
much harder to find, due to all the trees suffering from Dieback
disease, to the extent that it’s basically getting unobtainable.
We use ash at work, in guitar making. It’s now reserved only for
our best guitars, as it’s gotten so difficult to obtain in
quality quantities..
Ive used quite a lot of Obeche in my build. It’s similar to
balsa, but denser and much stronger. It was used most famously
in the dH mosquito. It shrinks and moves quite a bit, so you
need to make sure it’s fully seasoned, and it’s full of silica
which can be a bit of a bear on cutting tools and lungs, but
apart from that it’s really nice.
Coincidentally; ash and Obeche make great sounding guitars, but
oak sounds rubbish because there’s no resonance. ;c)
#Post#: 6129--------------------------------------------------
Re: Wooden chassis
DIR By: RhysN
Date: March 23, 2022, 4:38 am
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--- Quote from: David F-R link ---
>
> Excellent start to the topic.
>
> Oak for the chassis sides? I was wondering about some straight
grained pine. It's used extensively for structural work.
>
> (Personally, I do have plenty of oak 'in stock' but \I was
thinking about what is readily available and cheap.)
>
--- End Quote ---
It was oak just because the local timber merchants have a place
where you can look at "stuff", pieces that have been cut etc.
These were in there. No other reason.
For my Morgan re-build I bit the bullet and bought ash.
Initially I framed it with selected pallet material so that I
didn't make any major mistakes with the ash. In reality the
pallet timber, when it was good grain structure was hard to tell
from the ash!
I have used whatever is available, including Pawlonia for
grille/radiator shells, even nicer than obeche!
There was also the Darracq T700 that Wes Raynor built which was
all wood/ply. I believe to be one of the first 3 cyclekarts in
GB, the list includes Bill (Giant Tribble) and Geoff May who was
first? All 3 built differently from each other.
#Post#: 6133--------------------------------------------------
Re: Wooden chassis
DIR By: Jimr1999
Date: March 24, 2022, 1:32 am
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For mine, I started with table 1 here...
HTML http://nhbccampaigns.co.uk/landingpages/techzone/previous_versions/2010/Part6/section4/appendix.htm
Which gives spans of joists permissible for building regs for an
imposed load of 1.5kn/msq for various joist centres for
relatively low grade C16 stress tested whitewood joists (Spruce
et al)
I chose a stronger timber with a straight grain with few knots
and chose tangentially cut pieces. (my section sizes are smaller
than the smallest on the table)
From the table, even the smallest cross section would span our
wheelbase, though looking at the state of some of the C16 we get
at work I would never risk it.
The weak points on my design have been gusseted with ply and a
high strength low creep adhesive that is WBP (weather and boil
proof)
As I mentioned on my build page, it has not got a lot of
torsional rigidity at the moment which I believe I can address
with some bracing between the rails and the bodywork/floor as a
joined box with glue blocks (like a classical guitar) and braces
under the floor (Like a steel strung guitar top)
... Will it work? Feck knows, but I'm having fun
#Post#: 6134--------------------------------------------------
Re: Wooden chassis
DIR By: David F-R
Date: March 24, 2022, 4:15 am
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So much useful information - thanks guys.
Following the principles of 'what can anyone get hold of' and
'what can I scrounge', I shall do a bit of looking around.
When I go to diy stores for softwood, I usually rummage through
the stock for decent stuff and get very picky. Might try that
next time I'm in one. In the meantime, my '34 Riley with box
steel frame is first priority (after boat, house, loco and list
from the management).
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