ghetto_eddie
|
| posted on 6/5/08 at 05:54 PM |
|
|
GRP thickness/strength
Can anyone tell me (or provide me with a chart…etc) how thick 3 layers of 450g CSM would be? And also how resistant it would be to warping over a
large surface area?
I am planning a different method of making my bodywork plug but need to know how much I will be adding in thickness with that lay-up, and how tough
and resilient it will also be.
Also what kind of lay-up does a normal GRP bodied car have?
Regards
Edd
|
|
|
|
|
twybrow
|
| posted on 6/5/08 at 07:16 PM |
|
|
About 1.5mm thick. Are you just planning on making one big sheet? Why the warping question?
|
|
|
Volvorsport
|
| posted on 6/5/08 at 07:42 PM |
|
|
3x450 would be about 5mm thick with gelcoat maybe more.
and also really heavy .
most kitcar layups are 1x600g for sevens , it really depends on the use you are using it for .
www.dbsmotorsport.co.uk
getting dirty under a bus
|
|
|
dubstar_04
|
| posted on 6/5/08 at 09:05 PM |
|
|
If you need actual figures I can work out the specifics for you, However I would recomend using a good quality gelcoat and tissue as the first layer,
letting that go off, then removing it from the mould, place back in the mould and build with thin layers of chopped stand matting.
This will give the best finish and optimum strength.
Pointer:
Don't use too much resin as it will make it heavy without adding strength. The best way to impregnate (Giggerdy) the matt is to use a roller and
apply the resin away from the mould then lay the matting into the mould and roll the air out working one way across the mould with a mincer or a clean
roller (the small foam type).
This method will give you the strongest possible product without being resin rich and over weight, and should also help reduce voids!!
Cheers,
Dan
[Edited on 6/5/08 by dubstar_04]
|
|
|
ghetto_eddie
|
| posted on 7/5/08 at 07:55 AM |
|
|
The reason i ask is:
I have a different method of making my bodywork plug in mind. By creating a strong and stiff GRP "shell" over my plaster/wood plug. Then
remove the plater/wood plug from within... leaving just a shell.
Then i plan to HEAVILY reinforce the centre with a temp framework and more GRP... and go onto the final bodywork stages with filler from there.
Reasons being:
1. Liberate some room in my garage..(store within the plug)
2. Allow me to use a temporary chassis to move it about.
3. remove the problem of the wood/plaster shifting underneath the plug.
4. It will allow me to create detail such as inner wheel arches/door steps...etc which i would not be able to do before (main reason)
Allows me to split the bonnet/doors from the rest of the bodywork before
But what i need is a "skin" that is strong enough to hold shape till i can reinforce it from the centre.
Hence my question.
Ideally i am looking for the strongest layup that will give me less than 6mm thickness but hold it's shape VERY well (no flexing/distortion) I
would think Bodywork thickness should do for this... but maybe thicker than ususal...
Could anyone give me more information on usual body layup (in csm...no gel). And also... anyone any idea what the surface area of a standard car is
(not a seven!)?? as that could help me with with how much i csm i need to buy.
Edd
[Edited on 7/5/08 by ghetto_eddie]
|
|
|
Fred W B
|
| posted on 7/5/08 at 11:35 AM |
|
|
Hi Eddie
I asked a similar question here
body layup.
In spite of what was stated there, I am planning maybe 3 to 5 mm shell thickness.
I estimated 8 m2, call it 10 m2 for the area of the body.
I think you are going to have lots of fun if you are trying to finish both sides of a skin to pull molds from both sides.
I've just started with the GRP work and lets just say now I know why I have been putting it off!
Maybe better to just layup a very thick skin over the pattern, and then cut most of the pattern away with a chainsaw if you want space inside the
pattern - I've considered it! 
Once you get the first panels off, than make up the inner shapes in them and pull inner moulds from that?
Cheers
Fred W B
[Edited on 7/5/08 by Fred W B]
[Edited on 7/5/08 by Fred W B]
You can do it quickly. You can do it cheap. You can do it right. – Pick any two.
|
|
|
ghetto_eddie
|
| posted on 7/5/08 at 01:03 PM |
|
|
Fred- i feel you may have missed what i was trying to say (or i missed yours??)
quote:
I think you are going to have lots of fun if you are trying to finish both sides of a skin to pull molds from both sides.
The intention is to pull moulds from the outside skin... the inside will be all ugly as sin reinforcements
The basic idea is to create the FG "skin" in exactly the same way as you have/will/are doing Fred, but that strengthening skin on yours
will be thicker on mine... creating a scructural shell.
Hopefully with enough strength to hold it's shape when the centre plug is pulled out (all the plaster/wood) leaving a rough looking
bodyshell.... which can then be reinforced to make as stiff as possible to be worked on from there to create a plug good enough for a mould.
Essentially the aim is to replace the plaster/wood buck, with a hollow GRP buck. Giving me more freedom of movement (ever moved a plaster/wood
buck??? JESUS its heavy!)
quote:
Once you get the first panels off, than make up the inner shapes in them and pull inner moulds from that?
Basically i am trying to accomplish this step in line with the rest of the workings (i.e in 1 step). The daytona differs from most scratchbuilds in
that it is a coupe... and so wheelarches/sills/windows are a big consideration, and i would like to have them all in 1 mould (a split mould
obviously!)
This will also allow me to do some basic chassis work underneath the plug, allowing me to move it around better!
|
|
|
