Damn sight neater than what I tried to make LOL !!
One query.
I tried to make a mould of one of my front wings, with a view to making either a carbon or glass replacement.
When making the mould, one of the biggest problems I had was air pockets in the glass. I was using 400gm sheet. Anywhere there was a fold or corner etc....the glass just wouldnt sit where I wanted and air pockets were formed.
You've managed to make a beautiful mould on a fully radiused and edged piece
If I tried a roller even on flat panels, the stuff just wanted to stick to the roller and lift up ? SO almost all work was done by stippling with the brush.
Monkey business
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stevieturbo
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Hi Steve
I suspect that your problems were twofold.
Firstly did you gel the wing or just lay glass straight onto the wing?
If no gel was applied then the edges would have been really difficult to glass because of the sharp edges.
If you did do this then the answer would have been to use a Thixotrope powder which bulks the resin up and makes it heavier so it lays down flatter.
Also it would have depended on how much excess glass you had laying over the edges.
If you go back a few pages on this thread you will see that the little blocks helped tremendously in avoiding this exact situation and whilst it was simple to do in this application it may not have been in yours.
When doing a large panel like a wing it is ALWAYS best o have it laying flat and glass the larger faces first.
That way when you get to an edge the glass is already wet and will naturally want to fall down the short face.
With regard to the corners the easiest way of dealing with this is to tear the glass prior to wetting out.
Any excess can then be torn off and thrown away .
By doing corners this way when the glass is wet out you can sort the nasty bit first and not trap air .
Folds are never a good idea in glass as it creates stress riser's which can lead to cracking and de lamination.
Have a look at this Steve as it may make things a bit clearer for you.
http://www.v8forum.co.uk/forum/viewtopi ... &start=120
The problem you had with the roller 'picking up'I suspect is that you used a paddle roller as opposed to the fin roller that I prefer to use.
Paddle rollers have hard edges and these only need the slightest hair of glass sticking up to catch.
The other reason could simply be because you did not have enough resin on the glass in the first place this would also cause the glass hairs to stick up.
Once wet out you can leave glass for up to 10 mins before you roller out.
Using a roller always is better than just stippling but sometimes you have no choice.
Do this help answer your questions ?
cheers
P
I suspect that your problems were twofold.
Firstly did you gel the wing or just lay glass straight onto the wing?
If no gel was applied then the edges would have been really difficult to glass because of the sharp edges.
If you did do this then the answer would have been to use a Thixotrope powder which bulks the resin up and makes it heavier so it lays down flatter.
Also it would have depended on how much excess glass you had laying over the edges.
If you go back a few pages on this thread you will see that the little blocks helped tremendously in avoiding this exact situation and whilst it was simple to do in this application it may not have been in yours.
When doing a large panel like a wing it is ALWAYS best o have it laying flat and glass the larger faces first.
That way when you get to an edge the glass is already wet and will naturally want to fall down the short face.
With regard to the corners the easiest way of dealing with this is to tear the glass prior to wetting out.
Any excess can then be torn off and thrown away .
By doing corners this way when the glass is wet out you can sort the nasty bit first and not trap air .
Folds are never a good idea in glass as it creates stress riser's which can lead to cracking and de lamination.
Have a look at this Steve as it may make things a bit clearer for you.
http://www.v8forum.co.uk/forum/viewtopi ... &start=120
The problem you had with the roller 'picking up'I suspect is that you used a paddle roller as opposed to the fin roller that I prefer to use.
Paddle rollers have hard edges and these only need the slightest hair of glass sticking up to catch.
The other reason could simply be because you did not have enough resin on the glass in the first place this would also cause the glass hairs to stick up.
Once wet out you can leave glass for up to 10 mins before you roller out.
Using a roller always is better than just stippling but sometimes you have no choice.
Do this help answer your questions ?
cheers
P
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stevieturbo
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- Location: Northern Ireland
Thanks, and very much so.
Yes the roller was more a knurled type finish, and I'd say I'm fairly sure I didnt have enough resin on the workpiece prior to laying the glass.
So I was applying lots of resin on top of the glass after, then stippling it in
Edges, llps, flanges they all were difficult and there are air pockets between the gel coat and resin and glass, so I ended up cutting lots of small pieces to try and avoid this.
But it's all a learning process. I had thought of using some thinner glass, maybe 1-200gm at edges etc first and then laying 400 or heavier on top once I had nice sharp edges.
I probably could have done another gelcoat too...but wasnt sure if you could layer that
Another query was flange making....ie for the spllt. I've seen guys use clay on youtube, but dont you need some sort of flat surface for this ?
I ended up using thin cardboard with release tape over it, then tried to tidy it with wax. It worked ok, but bound to be a better solution.
Despite my problems I was surprised how easy it was though, just requires a bit of patience.
I was intending to make replacement panels from carbon, just not sure whether it will be worth the extra cost vs fibreglass when I'll be painting the parts anyway, and weight isnt that critical.
With only 2x400gm layers my first mould attempt was much stronger than I had expected.
Yes the roller was more a knurled type finish, and I'd say I'm fairly sure I didnt have enough resin on the workpiece prior to laying the glass.
So I was applying lots of resin on top of the glass after, then stippling it in
Edges, llps, flanges they all were difficult and there are air pockets between the gel coat and resin and glass, so I ended up cutting lots of small pieces to try and avoid this.
But it's all a learning process. I had thought of using some thinner glass, maybe 1-200gm at edges etc first and then laying 400 or heavier on top once I had nice sharp edges.
I probably could have done another gelcoat too...but wasnt sure if you could layer that
Another query was flange making....ie for the spllt. I've seen guys use clay on youtube, but dont you need some sort of flat surface for this ?
I ended up using thin cardboard with release tape over it, then tried to tidy it with wax. It worked ok, but bound to be a better solution.
Despite my problems I was surprised how easy it was though, just requires a bit of patience.
I was intending to make replacement panels from carbon, just not sure whether it will be worth the extra cost vs fibreglass when I'll be painting the parts anyway, and weight isnt that critical.
With only 2x400gm layers my first mould attempt was much stronger than I had expected.
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stevieturbo
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- Location: Northern Ireland
Good evening guys.
Well I thought I would try to do something a little different for you this evening so I have made with the help of my son a small video which hopefully shows the glassing process in real time and not through still photographs.
It also saves me a bit of time to!
Steve maybe this will help if you have another go.
The release agent I use is Mirror Glaze No.8 and on a first moulding basis always apply 8 coats.
Using different colour gels on different sections help massively when seeing the pairing lines.
In this case I have used the yellow and orange because they are so bright and for an old fart like me that helps a lot.
I generally use whatever is to hand for the fence and in this case it was the acrylic sheet but have used all sorts of things ranging from steel to aluminium cardboard to wood to perspex to masking tape.
With regard to using tape it does not really matter what you use as long as its waxed.
I cut the entire bow off a badly damaged dive boat some years ago and used cardboard to form the new shape.
Worked a treat although I'm sure the owner of the boat though I was having a laugh at the time.
For gel coat application as long as you dont use an MW solution (basically a liquid with wax in it ) you can put coat after coat after coat on.
We regelled an entire yacht some years ago changing it from cream to dark blue and applied eight coats on that and then just sanded back and polished it up.
Anyway have a look at this.
Although not seen in the video I have glassed all six layers tonight and as it is not that warm and I used a smaller amount of catalyst in the resin than I would normally do I am confident that the whole lot wont get too hot when curing and shrink badly.
Here's the finished unit
Obviously it will need trimming but that wont take too long to do and then it must be left for a few weeks to cure
Cheers
Mr Monkey
Well I thought I would try to do something a little different for you this evening so I have made with the help of my son a small video which hopefully shows the glassing process in real time and not through still photographs.
It also saves me a bit of time to!
Steve maybe this will help if you have another go.
The release agent I use is Mirror Glaze No.8 and on a first moulding basis always apply 8 coats.
Using different colour gels on different sections help massively when seeing the pairing lines.
In this case I have used the yellow and orange because they are so bright and for an old fart like me that helps a lot.
I generally use whatever is to hand for the fence and in this case it was the acrylic sheet but have used all sorts of things ranging from steel to aluminium cardboard to wood to perspex to masking tape.
With regard to using tape it does not really matter what you use as long as its waxed.
I cut the entire bow off a badly damaged dive boat some years ago and used cardboard to form the new shape.
Worked a treat although I'm sure the owner of the boat though I was having a laugh at the time.
For gel coat application as long as you dont use an MW solution (basically a liquid with wax in it ) you can put coat after coat after coat on.
We regelled an entire yacht some years ago changing it from cream to dark blue and applied eight coats on that and then just sanded back and polished it up.
Anyway have a look at this.
Although not seen in the video I have glassed all six layers tonight and as it is not that warm and I used a smaller amount of catalyst in the resin than I would normally do I am confident that the whole lot wont get too hot when curing and shrink badly.
Here's the finished unit
Obviously it will need trimming but that wont take too long to do and then it must be left for a few weeks to cure
Cheers
Mr Monkey
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unstable load
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Paul, you mention that the gelcoat and laminates shrink back as they cure.
Is there a rule for this or is it all dependant on the amount of resin, type of resin, temperature and humidity and whether it's chopped strand or roving?
It's quite enlightening reading your posts and recalling things that I have done and how I managed to totally bollox some of them up and the ones I got right, mostly by accident than by design.
I have been badgering my boss to send me to do an Aircraft Composites course, but they haven't fallen for it, sadly.
Ah, well, struggle on, rewardless.......
Is there a rule for this or is it all dependant on the amount of resin, type of resin, temperature and humidity and whether it's chopped strand or roving?
It's quite enlightening reading your posts and recalling things that I have done and how I managed to totally bollox some of them up and the ones I got right, mostly by accident than by design.
I have been badgering my boss to send me to do an Aircraft Composites course, but they haven't fallen for it, sadly.
Ah, well, struggle on, rewardless.......
Cheers,
John
John
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stevieturbo
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- Location: Northern Ireland
Hi All
Thank you so much for the nice comments.
I am always concerned that folk might feel that I show these things that I do for self serving and ego stroking reasons but I promise it is not the case.
Darkspeed (sorry dont know your name )
I am using 600gsm chopped strand matting and isophthalic resin.
600 plus resin gives a tad over 1mm thick per layer so I end up with something approximately 8/9 mm perfect for a mould of this size.
The shape is totally irrelevant to the thickness's in this case but if you had to ever so slightly flex the mould to help with release then you could use less glass in the flex areas.
John
Cure rates are very often overlooked by the mass production guys as it a case of lay it up flash it off and get it out the door.
I like to leave things once laminated at least two weeks if at all possible in stable ish temps.
This allows an even cure over the whole item.
How many times have you seen badly rippled and distorted glass items.
Just not left in the mould long enough.
A standard size car wing with 3 layers of glass should really stay in the mould for about 3 weeks.
You can 'post cure' which is something I will be doing with this once I have the actual unit produced and will show the PC process then.
Laminate thickness and relative amounts of resin will generate different amounts of heat as they cur so sometimes it is best to lay up 3 or 4 layers let is flash off and then do another 3 or 4 depending on how thick you want to go.
I cut down on catalyst last night as I wanted to get the whole lot done in one hit but it has cured beautifully and is now in the 'green 'stage which means it is internally still quite soft ( relatively speaking ) and will take roughly three weeks to be workable without it distorting.
Reg
Anyone could do this honestly.
Steve
You are right I did put dry glass down but the underlying laminates were wet and I drew some of the underlying resin through to help with the process.
Kevlar is sometimes pre impregnated with resin as is carbon so this goes into the mould almost totally dry
.It is then gently eased into place and gently and very lightly wet out before going into a clave and being cooked this super heats the whole lot and forms an incredibly strong composite panel.
Carbon is generally wet out in the same way as shown here but using epoxy resin as opposed to polyester.
Epoxy is much stronger as it uses a chemical as well as a mechanical bond whereas this project is pretty much all mechanical..
I hope this all make s sense to the questionaires and maybe answers questions for those who are just watching.
Thank you so much again for the kind comments.
cheers
Paul
Thank you so much for the nice comments.
I am always concerned that folk might feel that I show these things that I do for self serving and ego stroking reasons but I promise it is not the case.
Darkspeed (sorry dont know your name )
I am using 600gsm chopped strand matting and isophthalic resin.
600 plus resin gives a tad over 1mm thick per layer so I end up with something approximately 8/9 mm perfect for a mould of this size.
The shape is totally irrelevant to the thickness's in this case but if you had to ever so slightly flex the mould to help with release then you could use less glass in the flex areas.
John
Cure rates are very often overlooked by the mass production guys as it a case of lay it up flash it off and get it out the door.
I like to leave things once laminated at least two weeks if at all possible in stable ish temps.
This allows an even cure over the whole item.
How many times have you seen badly rippled and distorted glass items.
Just not left in the mould long enough.
A standard size car wing with 3 layers of glass should really stay in the mould for about 3 weeks.
You can 'post cure' which is something I will be doing with this once I have the actual unit produced and will show the PC process then.
Laminate thickness and relative amounts of resin will generate different amounts of heat as they cur so sometimes it is best to lay up 3 or 4 layers let is flash off and then do another 3 or 4 depending on how thick you want to go.
I cut down on catalyst last night as I wanted to get the whole lot done in one hit but it has cured beautifully and is now in the 'green 'stage which means it is internally still quite soft ( relatively speaking ) and will take roughly three weeks to be workable without it distorting.
Reg
Anyone could do this honestly.
Steve
You are right I did put dry glass down but the underlying laminates were wet and I drew some of the underlying resin through to help with the process.
Kevlar is sometimes pre impregnated with resin as is carbon so this goes into the mould almost totally dry
.It is then gently eased into place and gently and very lightly wet out before going into a clave and being cooked this super heats the whole lot and forms an incredibly strong composite panel.
Carbon is generally wet out in the same way as shown here but using epoxy resin as opposed to polyester.
Epoxy is much stronger as it uses a chemical as well as a mechanical bond whereas this project is pretty much all mechanical..
I hope this all make s sense to the questionaires and maybe answers questions for those who are just watching.
Thank you so much again for the kind comments.
cheers
Paul
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stevieturbo
- Forum Contributor
- Posts: 3979
- Joined: Sat Nov 18, 2006 6:22 pm
- Location: Northern Ireland
The popular DIY process for carbon is the resin infusion.
Vacuum job but no oven, all room temperature kind of thing. Presumably that's all down to the resin used ?
Which creates more strength, the resin or the glass/carbon/kevlar ? It looks to be as if the resin really is a key structural component ?
Very interesting about timescales. Some of mine was spread out over a few days...more down to time available than anything.
But the place I bought all my stuff from seemed to suggest a much faster approach t it all ! re-layering etc within a short time, and not to leave it for days.
They didnt say I couldnt do that, but it was best not to.
Vacuum job but no oven, all room temperature kind of thing. Presumably that's all down to the resin used ?
Which creates more strength, the resin or the glass/carbon/kevlar ? It looks to be as if the resin really is a key structural component ?
Very interesting about timescales. Some of mine was spread out over a few days...more down to time available than anything.
But the place I bought all my stuff from seemed to suggest a much faster approach t it all ! re-layering etc within a short time, and not to leave it for days.
They didnt say I couldnt do that, but it was best not to.
For panels it's also worth looking at other glass cloths and not just chopped strand - A woven glass is also very strong per unit weight as it holds much less resin and for stiffness consider core materials.
The old 70's race cars used woven glass composites - for strength per unit weight and far easier to obtain good overall uniformity in a panel.
Andrew.
The old 70's race cars used woven glass composites - for strength per unit weight and far easier to obtain good overall uniformity in a panel.
Andrew.
4.5L V8 Ginetta G27
Steve
My apologies as I have caused some confusion for you.
When I say 'flash off' ' I mean in this instance an hour or so and then laminate again.
By doing this you don't build the internal heat up as the chemicals cure.
I have seen on several occassions guys laying up a mould leave it for an hour and then release which leads to no end of trouble but its not for me to poke my nose in when its not my work or project.
Resin infusion is massive down here in Plymouth but the majority of the items being produced are post cured.
Princess Yachts International resin infuse up to and including 40 mtr long super yacht hull and then make them into £16.7 million floating palaces.
The resin does have some strength obviously but it is always the laminate that holds the most structural strength.
Technology has advanced so much that for the past ten years or so it is sometimes hard to keep up with everything and there has been again for some time a resin that cures instantly with UV light and is used extensively on mass production runs making such things as surfboards and the like.
For you leaving a panel for a few days before continuing will not cause any problems as there will be no heat generation after a couple of days so you can add to your item as required without fear.
I hope this clears the confusion?
Cheers
P
My apologies as I have caused some confusion for you.
When I say 'flash off' ' I mean in this instance an hour or so and then laminate again.
By doing this you don't build the internal heat up as the chemicals cure.
I have seen on several occassions guys laying up a mould leave it for an hour and then release which leads to no end of trouble but its not for me to poke my nose in when its not my work or project.
Resin infusion is massive down here in Plymouth but the majority of the items being produced are post cured.
Princess Yachts International resin infuse up to and including 40 mtr long super yacht hull and then make them into £16.7 million floating palaces.
The resin does have some strength obviously but it is always the laminate that holds the most structural strength.
Technology has advanced so much that for the past ten years or so it is sometimes hard to keep up with everything and there has been again for some time a resin that cures instantly with UV light and is used extensively on mass production runs making such things as surfboards and the like.
For you leaving a panel for a few days before continuing will not cause any problems as there will be no heat generation after a couple of days so you can add to your item as required without fear.
I hope this clears the confusion?
Cheers
P
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stevieturbo
- Forum Contributor
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- Joined: Sat Nov 18, 2006 6:22 pm
- Location: Northern Ireland
I think I get it...
It's all over my head though, but I'll continue with the project to make some parts.
It may take a few years, but I'll get there eventually lol
The resin infusion sounds good as it will mean the fabric is forced into shape via the vacuum, plus in theory it should give me time to lay things out without worrying about getting it wrong and it all going hard etc.
But the basic fibreglass stuff seems to cheap by comparison
It's all good though and learning a lot here, thanks !
It's all over my head though, but I'll continue with the project to make some parts.
It may take a few years, but I'll get there eventually lol
The resin infusion sounds good as it will mean the fabric is forced into shape via the vacuum, plus in theory it should give me time to lay things out without worrying about getting it wrong and it all going hard etc.
But the basic fibreglass stuff seems to cheap by comparison
It's all good though and learning a lot here, thanks !
