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Seat fixing and iva.
Jenko - 26/12/12 at 09:39 PM

I want to bolt the seats direct to the floor of my sylva j15, however, I also want to recline the seat back which means the front needs to be elevated around 50mm.

The bottom of the seat has a captive nut built into it (m8), using some large cotton real rubber mounts seems like a good idea...I can't see any reason in the iva manual not to use them....but would appreciate thoughts on this.

[Edited on 26/12/12 by Jenko]

[Edited on 26/12/12 by Jenko]

ReMan - 26/12/12 at 10:15 PM

I see no reason why not, as long as it's fully secure.
Presumably will use the same chassis mount point s anyway so should be fine

snapper - 27/12/12 at 07:31 AM

I would worry about the cotton reel shearing in an accident
Perhaps some 50 x 25 square tube across the two seat mount holes with a bolt through the floor and a load spreading washer under the floor would be more IVA compliant

[Edited on 27/12/12 by snapper]

avagolen - 27/12/12 at 01:51 PM

I thought that the seats had to be adjustable on new builds?

Confused.

loggyboy - 27/12/12 at 04:58 PM

quote:
Originally posted by avagolen
I thought that the seats had to be adjustable on new builds?

Confused.


They have to adjust if they were designed to be adjustable, ie if you fitted seat runners they would need to work. If the car was designed with a fixed seat its ok.

loggyboy - 27/12/12 at 05:05 PM

quote:
Originally posted by snapper
I would worry about the cotton reel shearing in an accident


Seat does very little in an accident (in a seven at least) as theres no where for it to go. I would be more worried about them sheering under general use and doing very little anyway. Just bolt them straight up.

Jenko - 27/12/12 at 06:13 PM

My understanding about the seats (as mentioned), is if you have runners they must work in three positions, if they are fixed, then there is no adjustment to test.

Re the rubber mounts...they seems to last well for the exhaust and even engine, so would thinkt they would be ok.....plus as I understand t they are very strong...I'm talking about the m8 bolts and 40mm dia ones, not the small ones.

loggyboy - 27/12/12 at 08:32 PM

I just cant see what advantage the rubber mounts would give. Other than spacing, which could be achieved with washers.

Jenko - 28/12/12 at 02:47 PM

quote:
Originally posted by loggyboy
I just cant see what advantage the rubber mounts would give. Other than spacing, which could be achieved with washers.


No advantage...but the front of the seat needs raising around 50mm... That would take a lot of washers, plus,as the front raises up the angle from the bolt through the floor would become more, the rubber means you could account for this. It just seems to offer a cheap, light, simple solution.

hellblue - 28/12/12 at 09:48 PM

Maybe its just me ? but if you plan on a retest then go ahead with the rubber mounts !

RS1 ....
Every seat must be securely attached to the vehicle structure, or other obvious suitable load bearing parts of the vehicle

via a bit of rubber, i would suggest falls very short of the above !

[Edited on 28/12/12 by hellblue]

ReMan - 28/12/12 at 10:12 PM

Well that told us.
You better get the welder out!

loggyboy - 28/12/12 at 10:34 PM

quote:
Originally posted by hellblue
Maybe its just me ? but if you plan on a retest then go ahead with the rubber mounts !

RS1 ....
Every seat must be securely attached to the vehicle structure, or other obvious suitable load bearing parts of the vehicle

via a bit of rubber, i would suggest falls very short of the above !

[Edited on 28/12/12 by hellblue]


I would imagine the engine, exhaust and fuel pump needs to also be securely attached to the vehicle structure, but they're not failed on being mounted on rubbers!

Jenko - 29/12/12 at 08:03 AM

It's a good point and this is why I posted.....what defines securely? I would suspect the rubber mounts are very strong, but what defines securely.

loggyboy - 29/12/12 at 09:21 AM

Secure would be anything that is unlikely to fail under the stresses of normal use and time. I think the rubbers providing they were not too small, would pass IVA, however I would expect a aluminium spacer would be lighter and better option. As I would want to feel things through my seat, not have things isolated/insulated. It mayu also lead to some movement under heavy load which might feel weird or confuse the sense

ReMan - 29/12/12 at 09:27 AM

I think that the cost/weight/benefit is probably the biggest driver and I 'd agree that if a bit of ally would do it then save the expense of the rubbers unless you've got a bucket of them

907 - 29/12/12 at 09:52 AM

I would have thought that the simple solution would be to bolt a couple of pieces
of box to the seat, then bolt the boxes to the floor. (see pic)


Description
Description

Paul G

Slimy38 - 29/12/12 at 10:51 AM

quote:
Originally posted by loggyboy
It mayu also lead to some movement under heavy load which might feel weird or confuse the sense


Taking that a bit further, if you consider your body weight while cornering, the rear solid fixings would have to accept the (slight) movement of the front rubber fixings. That could lead to early weakening or failure of the rear fixings.

If you compare it to an engine rubber mount, they're all rubber so they can all move as the engine moves.

I'd say the seat fixings need to be all flexible (which I would expect to be an IVA fail?) or all fixed.