Prototype

[Ionit]

Hey Dominic.
Very nice work. Your right it has been a while since you've posted. I remember way back in August 03 I was one of the first and last to reply to your broken frame post. I was the one wondering where you went. When I saw your frame post I was pleasantly  surprised you didn’t drop off the face of the earth.
I am still eager to know some of the details. I've finish reading a book about Fiber Reinforced Plastics which left me hopelessly confused. So I decided to put off fixing my  "K2 5500 C" and just paint it with urethane instead.
Now I feel uplifted and have enough courage to fix it myself. Unfortunately I fried my digi cam memory card and cannot take any pictures of the damage to my bike.

How did you make the mold? (plaster of paris, Hydrocal B11, polyurethane foam, latex)
Did you use a “gel coat” in the mould?
Did you use a vacuum bagging pocess?
Did you use any structural foam for the core or did you keep the sub frame. (The sandwiched piece of carbon inside the mainframe)?
What kind of weight is the carbon cloth with what epoxie.
If it was West Systemes product which epoxie hardener combonation did you use.

sorry for so many questions. You got me exited.

[Proflexman]

Sorry m8 you feel exited, still better to be leaving  [smiley=laughing.gif]
I could not resist the Pun.
A techie question yum.
Your making this way too hard for yourself.
Here's some of my secret, firstly remove everything from the frame and un screw the black plates that have two small holes in each side, use a pair of circlip pliers, you may get lucky and both will unscrew, then this is the hard bit (very) you have to split the frame completely in half.
Not easy i can tell you, it took me nearly a couple of months of careful cutting between all the other things i have to do.
Between the two halves is a sort of baffle or plate, the glue was applied to this and the two half's were pressed together.
You will have to remove one half then the baffle, then its a job of cleaning up the surfaces.
Remove the metal parts and stickers, repair any damage to the outside of the frame with filler and sand smooth, you may wish to spray the frame with a two pack lacquer or a high build primer then a lacqur flatting back between the two coats.
Then you need some release wax, just like waxing the car but your not waiting for the wax to form a haze, you apply it and straight away polish it off, do this until you have done it a min of eight coats, then polish the frame up again with a soft cloth.
Because the frame halve's are small you wont suffer too much from distortion during the cureing process, but you can place a couple of battons across the frame, your looking at building a mould to a thickness of about twice the thickness of the frame.
Materials, use either 450 chop strand matt or you can use a material that has Kevlar in it as well for strength.
Use a Polyester resin and catalyst with a colour in it like Aircraft grey.
The colour will help show any defects when you seperate the two.
Dont forget to place some tape on the inside of the frame to cover the holes but not to hide them because you need to know where they are in order to cut the holes.
You still with me?
Now you have seperated the mould from the frame and discarded the frame.
At some point you will have taken the metal parts out of the frame maybe using some heat to release them and had some more made.
Check you mould carefully for defects, fill and sand as required.
Do the same again with the release wax, and paint the inside with West System resin 205/105 (use pumps which pump out just the right amount 1 pump of base to 1 pump of hardner) oh before you did this you will have bought the carbon and cut it a little larger and gently pressed it into the mould making sure you have a sharp pair sissors handy to cut where needed, apply more resin making sure the matt has soaked it all up and then apply another layer, you wont need so much resin this time just a soft paint brush to dab around the mould making sure it's soaked, any excess resin remove with a scraper or like.
Bear in mind that after taking a few moulds you will have to re apply the release agent to the mould.
And you may need to make new moulds as the mould breaks down with age.

Or better still take the frame to an injection mould maker, have him make the mould and a machine.
Some of them want to keep the moulds!!!, find one that will give you the moulds as well.
This way will cost you an arm and two toes.  

[Ionit]

Sounds simple enough. Its surprising you don't use gel coat. the text books say to use it for a brilliant finish, but I guess you don't need it if your spraying the frame with lacquer. I'll see what I can do about making a medium size mold and sending it to you if your interested.
Thanks for all that info. Those instructions with all of your other posts and pictures are twice as good as any info coming from an FRP forum ( http://www.fibreglast.com/phpBB2/index.php ).
My alias at that forum is Alain, my real name is Alex, Don't ask.

Now.   I am aware you have access to FRP manufacturing equipment at work, correct me if I'm wrong about that. Would someone without access to professional equipment be able to complete this process with cheapo tools a small pump and allot of motivation.

[Proflexman]

 [smiley=laughing.gif]
I like you determination.
The use of Gel coat is only realy used in the repair of yachts though it is used in manufacturing items, but do bear in mind that there are many types of Gel and for many diverse applications.
I would avoid the use of them in mould making.
Polyester resin is quite good enough for the making of moulds because using West System to make a mould is a very expensive way to go.
Please do not mix the two of them because they do NOT like each other and if you spend hours making an item it will be a pain if you have to start again.
Also remember this when using Polyester you must use some MW solution, it is liquid wax, and you will need to mix this in with your resin when making batch's of resin for making the mould.
Otherwise you will not be able to seperate the frame from the mould.
You see MW solution as the resin dries rises to the surface to form a non sticky surface.
West System already has the wax in it and depending on how cold it is you may get a leaching from it where the yellow'ish wax rise's to the surface, this may be removed with warm soapy water.
Dont be deterred.
Now your question, well yes Joe Bloggs could do this with determination as there's no great skill to it.
Practise this first.
Get a 3x3 sheet of glass and clean it on one side.
Lay it down on a flat surface.
Coat the glass with re-lease agent as i discribed.
Having cut your carbon matt already to size say 2.5 ftx2.5ft.
15 sheets should do.
This will give you a finish of say 8mm thick.
Have some three inch paint brush's handy, rubber gloves and acetone or nail varnish remover to clean up, and a roller which has special groves cut in it for working out bubbles.
Apply your resin then lay a sheet onto the glass and paint on gently more resin.
work the surface with the roller.
Apply another sheet and repeat and so on.
Then have a firm sheet of Formica with a smooth finish the same size as your carbon matts.
When your done lay the Formica sheet onto the resin soaked matt applying release agent to the surface that is on the matt.
Place a flat but not too heavy object onto the Formica the same size again.
Leave to dry say 5 hours.
Remove the flat plate and peel off the formica and you should with gentle persusion be able to remove you finished product.
Clean back the edges with a cross cut saw.
Your finished product will look like the dogs danglies.

Earlier i said Polyurathane ignore this i meant to say Polyester.

Once you have your sheet of carbon made you will be able to cut it to any shape using a scroll saw.
West is not UV resistant you must if liveing in a hot country or not spray on a lacquer to stop it breaking down.
Good luck and ask for more advise if you need it.

[smiley=nod.gif]

[Proflexman]

Please could someone weigh a large carbon frame with the swinging arm mounted.

Without the rear shock on for me.
Thanks.