small sports chassis weight

[scimjim]

Dunno if you have a scale suitable, but could you weigh a chassis? Maybe a spring type susepnded from an engine crane?

FINALLY managed to do this today and the results are:

non-galv: 97.5 Kg (minor bits fitted - 2 x CVH rubber engine mounts, 3 x rubber diff mounts, 4 x door hinges, bump stops)

galv: 105.3 Kg (only bump stops fitted) - edit, note below - this is a retro-galv without Ti engine mounts.

it was a real struggle, so only accurate to within a couple of Kg either way.

[Alan SS1]

Jim

Two Questions
1 is the non galv one ferrous oxide free??
2 how many weight savings are in above non galv!!
Make that three Qs
3 how much weld on non galv!

Seriously 7 or 8kg is fair bit extra from the Zn (or did Reliant increase the overall gauge of the later chassis with the need for the Ti)

[Roger Pennington]

Seriously 7 or 8kg is fair bit extra from the Zn (or did Reliant increase the overall gauge of the later chassis with the need for the Ti)

I don't know if there were any change to the gauge, but the galv chassis did come with both engine mounts, which presumably would add a bit to the weight?

[scimjim]

Good point about the galv one being ferrous free - it's actually a Reliant retro-fit item and I can guarantee there is some internal corrosion because someone has bodged the earthing point and it cracked, so I ripped it out and can see inside (will try and take some pics later) - it does however mean that it doesn't have the additional Ti engine mounts.

sorry - don't understand Q2

the non-galv has been repaired (poorly) along the sills and a few inches up the A/B posts both sides as well as the NS bend where they crack by the exhaust downpipe.

Galvanising is generally accepted to add 7 or 8% weight to a chassis - the above works out to exactly 8% I think the gauge is identical.

[tony.idle]

it was a real struggle, so only accurate to within a couple of Kg either way.

The time honoured method is to hold the spring balance in one hand and lift up & hook the item to be weighed onto it with the other. Where's the struggle?

[scimjim]

a spring balance would have been a start Tony

turns out that the scale on the sheep pen outside, is an integral part, so I couldn't use that - as it was a rare day that I had an assistant that could lift a chassis (I don't want to kill poor Chris off ), we used the digital bathroom scales (that I bought to weigh everything as I took it off G97 and lightened). Although apparently good for 150 Kg, we obviously had to balance the chassis quite accurately to get a figure

[Alan SS1]

Jim
sorry Q2 toooo tangential
what I meant was how many fresh air sections were there (as in sections of sill that you can poke fingers through)
if it is any consolation the 'remains' of mine weighed in at around 100kg at local breakers yard, that was with fresh air and offset by the extra weight from corrosion. what EOL form?

bathroom scales 150kg jeeze thats > 350 lb that ??? Stone
USA bathroom scales?


PS I have a DIFF reinforcing plate here if it is required approx 2mm thick mild steel and plastic coated (well most of it is)

[scimjim]

ah - the sills had been repaired - only small holes showing but it was repaired without removing or cutting the tub, so the top inner joint isn't actually welded

It's from the car that I bought to repair G97 when DJ rolled it. The chassis turned out to be much better than advertised (I only paid £75 ) and I got a pair of QRG galv sills with a free car I collected a few weeks later

I have one of those diff mounting repair plates too

http://www.scimitarweb.co.uk/sgwrs/view ... diff+crack

[CNHSS1]

Great work Jim, i owe you a pint or 4 next time we meet!

Did it have the front shock mounting coss beam?

By the time you add the front armature, rear armature and largely unstructural tub, ill bet you will double the 100kg.

A Locost 7type is about 75kg, and a race spec 7type (Caterham superlight/bec westfield etc) 65 kg

[scimjim]

no crossmember, no brake pipes, nothing unless listed.

Rear armature is 8Kg, Front armature is 15Kg, Headlights inc motors etc are 9.6 Kg the pair, 6.8 Kg for the standard CVH rad and fan (inc crossbar) - there's 40 Kg straight away! I reckon I've got that down to 10Kg on G97?

nearly all of the weight of the tub is in the windscreen and surround as you know, I will weigh a body tub sometime too, guesstimate (from lifting it off the chassis today) is around 45 Kg

[scimmy_man]

non-galv: 97.5 Kg

sounds heavy, I remember picking one up at the factory, and asking why they didnt galv them, this would be very early in production life.

[tony.idle]

a spring balance would have been a start Tony

turns out that the scale on the sheep pen outside, is an integral part, so I couldn't use that - as it was a rare day that I had an assistant that could lift a chassis (I don't want to kill poor Chris off ), we used the digital bathroom scales (that I bought to weigh everything as I took it off G97 and lightened). Although apparently good for 150 Kg, we obviously had to balance the chassis quite accurately to get a figure

A friend bought a set of (what we assumed were) sheep pen scales at an agricultural auction. He was going to use them to measure hovercraft thrust. It turned out that the (numeric) scale was meaningless - apparently because there must have been a lever ratio between sheep & scales.

[scimjim]

Front crossmember is 2.3Kg

Bare body tub is 43.1Kg - over 20Kg of that is the windscreen and surround.

Pedal box inc servo & MC is 7.5Kg

[b.c.flat hat]

Just had a thought Jim, did CH ask you t'weigh him as well! All this talk of "bare body", "tub" and the like derailed my train o' thought!
Or 'as 'e got weight shift ideas for the peddler!

[Roger Pennington]

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