DNA Owners Club

DNA Owners => Other kitcar chat => Topic started by: Furrari on May 22, 2018, 11:51:49 AM

Title: Fibreglass and things
Post by: Furrari on May 22, 2018, 11:51:49 AM
Going back about four years to when I first had the current Furrari I had a rattle at the back.  This was finally tracked down down to the ( Mk1) calipurr support bracket.  DNA provided me with an upgraded set of brackets which were also fitted to later West Coasts.

Step forwards to quite recently, a familiar rattle returned.  The MOT was due the next week so while it was up on the ramp we had a look.   The brackets were OK but the calipurr itself was broken where it joined the bracket.

I just happen to have one original calipurr moulding and was going to use that but talking to various people at The Stoneleigh show it seems that we need about 10 of these in the club.  It would seem reasonable to see if we could reproduce these.

The stuff to make a mould has been ordered.  I’m debating how to do the calipurrs themselves.  The originals are made of PU but the equipment you need is quite expensive so I think GRP is my first choice.

Watch this space to see how we progress.

How hard can it be.
Title: Re: Fibreglass and things
Post by: OXO on May 23, 2018, 08:26:18 AM
Hi,
I managed to get a pair.

Has anyone tried the fake Brembo on ebay ?

https://www.ebay.co.uk/itm/Red-Brake-Caliper-Covers-Brembo-Front-Rear-Universal-Car-Truck-3D-4pcs-set-BMW/112907500144?hash=item1a49cfba70:g:7gkAAOSw~vpaQkl8

OXO
Title: Re: Fibreglass and things
Post by: Furrari on May 23, 2018, 09:51:47 AM
The first lot of stuff is in and the original moulding has been waxed.  Some people say you need three coats of wax, some up to ten.  I’m new to this so it’s had ten.

As the original has opposing dimples it will have to be a two part split mould so they won’t mechanically lock together.  Just waiting for the polypropylene sheet ( is 3mm sheet or plate?) for the split flanges.  Probably won’t arrive before Ragley but I can start the template for the flanges.
Title: Re: Fibreglass and things
Post by: Furrari on June 05, 2018, 03:54:40 PM
If anybody wants to see how moulds are made there are lots of vids on YouTube.  This is just what I’ve done.

Using a paper template I’ve made a barrier from 3mm polypropylene about half way along the calipurr and held it in position with some mould wax.  I’ve used more wax to seal the barrier to the caliper with it built up on one side and as flush as I could get on the other.  On the flush side I’ve put some squares of wax, cut at 45degrees to give a register for the two mould halves to mate together later.

I’ve given the this half a couple of coats of PVA mould release.  Put on one coat, wait for it to dry, tacky but dry enough for nothing to come off on your fingers.  Put the second coat on.   Let it dry for 24 hours(ish).
Title: Re: Fibreglass and things
Post by: Furrari on June 24, 2018, 05:20:52 PM
The calipurr job is on hold as I’m having a go with carbon fibre.

I’m not sure if this post should go here or on “well that didn’t work” ; but maybe it did.

I’ve got one or two jobs I want to do in CF finish.  After a local quote of £240 to dip the panel I want in CF finish ( with me doing the rubbing down) I thought I’d have a go at making a carbon fibre panel myself.

 First, what weave do I want.?  I ordered several CF samples and some resin and some bagging material.  Stuck the samples onto a bit of ABS board.  Applied the resin, the peel ply, the breather cloth and the vacuum bag.  Connected it to the vacuum tank and pump ( I already had these, as you do) and vacuumed these for a couple of hours and then left it all to cure over night.

This morning I tried to remove the bagging from the board.  The vacuum bag came off OK but when I tried to remove the peel ply it took the samples off with it.  Seems that ABS is not a good material to stick to and I had rubbed it down to too good a finish.  It needs to be rubbed down with 180 grit, and I used 400.

Not to worry, I was still able to put another coat of resin on to see what I liked and what suited the CF dip I already have.  So CF ordered.

What am I making?  Watch this space.  It’s big and if it works I’ll have a lot more to do.

M
Title: Re: Fibreglass and things
Post by: Furrari on June 26, 2018, 04:14:42 PM
As the weather is a bit hot to use the epoxy resin I went back to the calipurr mould.  Made the mix with just 1% hardener and it still set in about 20 mins. ( should take about an hour and a half).  Layered it up on the second part of the mould.  Let it set for about an hour ( usually I let it set overnight.). Drilled the bolt holes ( to clamp the two halves together later). Separated the mould from the pattern.  Separated the two halves.

RESULT. I now have a split mould for making West Coast calipurrs.

I’ll trim the furry bits around the edges and the sharp bits from the outside of the mould later.  I’ll practice a bit with vacuum bagging carbon fibre before I make my first CF moulding from this mould but things are looking good.
Title: Re: Fibreglass and things
Post by: MADMAN on June 27, 2018, 12:47:18 AM
Well done Furrari.
MADMAN
Title: Re: Fibreglass and things
Post by: kalifornia on June 27, 2018, 10:16:50 AM
Good Work
Title: Re: Fibreglass and things
Post by: Lee22 on June 27, 2018, 09:00:00 PM
Well done Mick
Looks good 👍🏻
Title: Re: Fibreglass and things
Post by: Furrari on June 28, 2018, 08:47:46 AM
Before I move on to a big project I though I could do with some practice so I decided to cover the fuse box cover; nobody will see it if all goes wrong.

Learning from my previous errors ( that’s what errors are for) I roughed up the surface with 120 grit and cleaned it to remove any dust.  I covered the surface with a black epoxy base coat and left it to set to a tacky surface.  Once it had set to the tack I covered it in the carbon fibre.  I’m using a material called pro-finish 'cos it’s suposed to be non-fray.  It’s not!  I’m laying it up to form a V patern.  After laying the CF I covered it in clear epoxy resin and it looked very good.  After covering it I bagged it up with the peel ply, separation ply, breather ply and vacuum bag, switched on the vacuum pump.  I released the vacuum after about an hour and a half and left it to finally cure overnight.

Next morning, with great excitement I un bagged it.   What a disappointment.  It was dull and the weave of the peel ply was pressed into the surface.   :-(

Oh well, I thought, I’ll give it a coat of resin anyway.   WOW as soon as the resin hit the surface it burst into life, what a change.  It looked amazing.  Took it into the sunlight and the two thread directions flashed as the sun hit them.  Fantastic.  Left it to cure.

It’s not to flash now it’s dried, but this is just the first coat.

Watch this space.
Title: Re: Fibreglass and things
Post by: kalifornia on June 28, 2018, 10:19:34 AM
I think you have to put a few coats on, before you get the depth and shine.
Well done
Title: Re: Fibreglass and things
Post by: Furrari on June 28, 2018, 02:46:14 PM
Cal.  That’s right.  A minimum of four coats, applied with the previous coat just still tacky, then left for a couple of days, sanded, then a top coat and then polished.  If you are going to use it outside in direct sunlight you need a UV stabilised gloss laquer, and then polish that.  This amount of labour is why CF components are so expensive.  It was just so disappointing to see such a dull finish from the bagging, but it’s the bagging that gives you the quality of the CF before you start getting the finish.
Title: Re: Fibreglass and things
Post by: Furrari on June 28, 2018, 03:54:05 PM
Yesterday I sprayed the back of the 15mm tow CF with a spray adhesive to stop it fraying. ( tow is a large checkerboard  patern  rather than the narrow woven stuff that you accociate with CF).   This morning I put a coat of clear on the box lid and waited for it to go tacky.  While I was waiting I trimmed the tow down to three rows, it didn’t fray so the adhesive seems to work.

When the coat reached the tacky stage I but the strip of tow down the middle and gave everything another coat of resin and then the performance of peel ply, separator ply etc etc.

I had a leak on the bag I couldn’t find so I could only manage a 40% vac instead of the 80% I have been but strangely I got a better result.  As I wasn’t pulling such a hard vacuum the pump didn’t have to work so hard so I will be installing a controlled leak for the next job.

After the bagging dried I removed it all and it wasn’t such a shock seeing the result.  A coat of resin over the whole lot and I’ve left it to dry overnight.  Again the wet resin brought it all back to life.
Title: Re: Fibreglass and things
Post by: Furrari on June 28, 2018, 05:49:29 PM
On applying the coat after the debagging it looks like the adhesive has reacted with the resin and it’s produced a reticulated effect ( its not supposed to).  If it was paint that was like this you would have to strip it all off and start again.  Because this is an epoxy resin I’m hoping it will be OK when I start sanding next week.  We shall see won’t we.

I should say in the sun it looks spectacular, even 'though it’s still wet.  Unsanded, unpolished and untaxed.
Title: Re: Fibreglass and things
Post by: Furrari on June 29, 2018, 02:01:12 PM
NEW WONDER MATERIAL.

You can forget Kevlar.  You can forget Twaron.  You can forget all those exotic Aramids.  I’ve found the ultimate.

Gafer tape and the epoxy resin you use laying up Carbon Fibre.  Do I offer it to NASA, DARPA or the Marines for their bullet proof vests, or all three.
It’s probably got a use in F1 as well.

M
Title: Re: Fibreglass and things
Post by: Furrari on July 03, 2018, 02:49:03 PM


I’ve finished the fuse box cover ( apart from the sides, which I can’t be bothered with).  It’s not too bad with only a few, very slight, fish eye marks in the surface.  The tow in the middle sometimes looks very good, flashing black and gold and sometimes a naff Gray.  Just depends on how the light catches it and reflects it off to you.  The twill CF looks very good in the herring bone style, again flashing black and gold as the light catches it.  The next job will probably use a 2” CF tape instead of the tow.

The badge/sticker seems to float in the resin rather than just be stuck on, with the patten of the tow visible behind it. which was the object of the exercise.

Was it worth the time, effort and cost?  No.  It never was going to be, it was just a job to gain the experience of working with vacuum bagging CF and finding what to do or not do ready for the next job.

Pic 1).  Just a general view of the cover.  The line across it is just a reflection of something or other.
Pic 2).  Another general view.  The sticker is almost in the middle.
Pic 3).  A close up of the sticker.  The picture does not do it justice.
Title: Re: Fibreglass and things
Post by: Furrari on July 04, 2018, 10:07:43 AM
So on to the first of the main jobs this CF thing is all about.

Going back four years to when the Furrari was being built, the boot carpets and load area cover were redyed black.  The carpets are still OK but the slider now looks grey and tired so it’s time for a refurbish.

While waiting for all the resin on the fuse box lid to cure I’ve striped down the cover.  Off come the handle and the front corner brackets that locate at the open end of the boot and tell the electronics that the cover is in place.  Off come the mechanism that ties in with keeping the back of the slider located level.  Finally the fabric cover at the back of the cover.  This was the hardest bit.  While the other bits were screwed on this part is held by some plastic strips that are ultrasonic welded to the cover.  These had to be drilled out.  How will it go back on, no idea, I’ll worry about this bit later.  Also the badges I had fitted were removed, they won’t be going back on.  The stickers I will need were ordered.

That’s it until after Castle thingy is over this weekend.

No pics 'cos there’s not a lot to see.
Title: Re: Fibreglass and things
Post by: Furrari on July 09, 2018, 04:37:19 PM
I’ve removed ( rubbed down is the wrong description) the flock from the load cover slider (lcs) thing.  Well I thought it was just flock.  Seems it’s a flock covered fabric which is then (very) stuck the the lcs.  Its very reluctant to come off.  What a mess it’s made in the Furrari R&D department, the stuff is everywhere.  I’m not even going to try to get it off my overalls ( the paper ones), I’ll just throw them out to get rid of the stuff.  I’ll vacuum tomorrow.

To change the subject slightly, I’m not 100% happy with the effect of the tow on the fuse box lid, so I’ve ordered a small amount of finer plain weave cloth and I’ll do back to back tests against the tow to see which I like best.  It’s a lot of extra work but I don’t want to have to do this job again so it’s worth the effort to get the effect that I want.
Title: Re: Fibreglass and things
Post by: Furrari on July 15, 2018, 09:22:09 AM
In the R&D department I’ve had another go with the CF tow and had a much better result than previously, so the material that I’m using for my “ racing strip” is sorted.  No picture, 'cos it doesn’t photograph well.

In the Composits Department I’ve changed my mind ( well what a surprise).  Rather than the load floor cover I’m doing the lock cover panel first.   Mainly 'cos it’s smaller, so should be easier and if it all goes wrong it’s much easier to revert to a black finish.

I’ve rubbed it down, it does seem strange taking a purrfectly well finished panel (Wayne originally sprayed it) and attacking it with 80 grit W&D, but that’s what it needs.

This is the panel I’m working on.
Title: Re: Fibreglass and things
Post by: Furrari on July 15, 2018, 07:29:29 PM
Prep of the panel.

I’ve taped behind all the holes with used mixing sticks behind the larger ones, then filled them with moulding wax.  This has a dual purrpose.   Firstly it stops the resin from going through the holes and making a mess and secondly it makes opening up the holes after it’s all set.

The first pic is of the lock hole and the second is the area where the useless Merc boot light and the 12v socket fitted.  Neither of these are needed as I will be refitting the lights on the underside of the boot lid and the load floor slider.  The CF will bridge these areas as though they were never there.
Title: Re: Fibreglass and things
Post by: Furrari on September 03, 2018, 12:15:34 PM
The skinning of this panel did not go well so it’s over to plan B.  Sand off the bits where it’s not given me the finish I wanted and start again.
Title: Re: Fibreglass and things
Post by: Furrari on September 06, 2018, 05:11:49 PM
Not doing very well with this carbon fibre stuff.  I’ve used carbon twill to cover the load floor slider.  It’s gone on well, but I don’t like it.  It doesn’t show the chevron paten as well as other jobs I’ve done, so I think I’ll just rub it down and give it a layer of the pro-finish.  It’s not unusual to put 2 layers on but it’s usually done for strength rather than appearance.
Title: Re: Fibreglass and things
Post by: Furrari on October 02, 2018, 11:53:47 AM
Progress at last.  I’ve sanded the load cover slider back to a smooth finish and redone it with pro-finish cf.  I’ve done it in several pieces to prevent the problems I had due to the change of shape.  The weave in a V patern with the tow on top is coming to life as the resin goes on, about three coats so far.  I need to rub down now to put the stickers on but I need to put the Furrari out of the garage to do that but the door is blocked with scaffolding as we are having the roof done.

No pics at this stage but I hope to put some on here as soon as I can.  It’s been a long steep road to get this far but I can see a light at the end of the tunnel, but that could be a train coming the other way.

Nigel.  Nothing done on the calipurrs yet but the leaning curve is there.

M
Title: Re: Fibreglass and things
Post by: Furrari on December 27, 2018, 02:37:52 PM
My IR heaters now installed and working in the composite shop.  I had a go at firbreglassing the two part mould I made for the spare calipurrs.  Only what I can call “ not of acceptable quality.” So they’re out.  I’m going to have a go at making some new moulds from latex and plaster of Paris so I can make some PU calipurrs like the originals.
Watch this space.
Title: Re: Fibreglass and things
Post by: Furrari on December 31, 2018, 01:13:15 PM
Brake Calipurrs.

This post is in real time.  If it works you’ll see it, if it fails you’ll still see it.

Progress so far.
You tube doesn’t say to give the pattern any pre treatment but I’ve given the existing DNA moulding six coats of wax polish, each coat was given 10 mins to dry and then buffed off.

I used an air drying clay to support the edge of the pattern and form a barrier to stop any latex seeping around it and forming a mechanical lock.  This was left to dry overnight.
That didn’t work so well because as the clay dried it shrank, leaving a gap between the pattern and the clay, so that was out.

I tried Gaffa tape starting about 1/8” on the pattern, over the clay and onto the baseboard.  This does seem to stick and give me what will be a flange over the edge of the pattern.

Next is onto the mould release preparation.  As I said I can’t find anything relevant on YouTube but I’ll err on the side of safety.  I’ve given my tape flange and the flat part of the pattern two coats of PVA release stuff but non on the calipurr part itself.  This was because the pattern having had six coats of resin doesn’t let the PVA form a flat skin, more like you would expect if you paint on six coats of carnauba wax and this would show up on the finished mould and component.

So it’s on to covering the pattern ( the face of the finished calipurr that you will see) with latex.  This will need lots of coats with it drying in between, I’ll post again when I finish this stage.

Oh yes, I nearly forgot.  A preposterous new year to you all.
Title: Re: Fibreglass and things
Post by: Furrari on January 06, 2019, 01:59:22 PM
As youngsters most of us have had a go with making things (such as chess sets) from a set of purchases rubber moulds.  These are usually 2.5” to 3” high max.  Usually works, no problems.

It’s a different matter when you have to make the mould yourself.  The only work I’ve done with latex was a control system for making rubber goods for the sex trade.  An interesting job, I used the same system later the same day for controlling the fuel rods in a nuclear reactor.

Anyway back to the current time.  The bottle of latex says 8 coats of latex, up to 16 coats on a large job.  YouTube just tells you to put some latex on your pattern.  Don’t believe it.  After 8 coats of latex as it comes out of the bottle it’s still only a thin layer.  I bought some thickener and used that in the latex.  After 14 coats it looked reasonable so it got another layer with a layer of cheese cloth in it.  Then another layer of thin and then another layer of thickened to make sure there are no pin holes the fibreglass can lock on.

I’ve just bonded half a dozen blocks onto the surface that I can use as a register for the fibreglass.  One more coat of thickened latex to go on over these to make sure there are no mechanical locks.

Just a pic of the job with its first coat of mould release.  It will have two or three depending on what it looks like after the second.

I sure hopes this works.
Title: Re: Fibreglass and things
Post by: Furrari on January 06, 2019, 07:37:49 PM
Second coat on, won’t need a third.  So it’s fibreglass tomorrow.

Just a tip.  If you are applying a second coat of something like mould release and it’s difficult to see there you’ve already put some on a bit of pigment in the mix helps.
Title: Re: Fibreglass and things
Post by: Furrari on January 07, 2019, 03:57:42 PM
Fibreglass Mother mould ( the support for the latex mould) made.  Mixture of carbon fibre, woven FG, and CSM. ( why CF?  It’s just off cuts from other jobs and are too small to use on proper jobs). No pics 'cos it looks the same apart from three legs made from old paintbrushes.

Do you know why milking stools have three legs and not four?

It’s 'cos the cows got the udder.

And with that I’ll post the separation picture tomorrow.
Title: Re: Fibreglass and things
Post by: Furrari on January 08, 2019, 03:15:03 PM
The outer face of the latex mould and the pattern and the corresponding mother mould released from the baseboard.  The pouring gate and risers glued onto the the internal face.  Two coats of brushable mould release brushed on and two coats of sprayable mould release sprayed on to the surface and the pouring and rising gates.  Everywhere that even looked as it it might trap air got a rising gate.

Start latexing this side of the mould tomorrow.

I’m sure there is an easier way of doing this but my lack of experience is a problem.

Just a pic of the job with all the gates and release stuff on.
Title: Re: Fibreglass and things
Post by: Furrari on January 12, 2019, 11:26:55 AM
Finished the latexing last night so it’s the mould release layer today.  Interestingly I used latex from a different manufacturer on this face.  Only needed eight layers to build up to the same thickness as 20 odd layers on the first side.  It only needed less than 1/3 of a bottle as opposed to most of a bottle.  Can only assume there were more solids in the second.

(Added a bit later).  I must say the job looks a lot better in the last pic than it does with 8 coats of latex and a layer of mucky mould release.  Still it’s the final job that matters ( and I sure hope that looks good, I have a lot of time invested in it.)
Title: Re: Fibreglass and things
Post by: nigelhob on January 14, 2019, 06:15:27 PM
hi furrari

brilliant news well done
please let me know when
i can purchase.
many thanks and once again
well done

nigelhob
Title: Re: Fibreglass and things
Post by: Furrari on January 15, 2019, 12:09:48 PM
Nigel.

Hi there.  Will do.  I’ve posted all stages of this project so everybody can see the success and failure of my learning curve.  I hope to separate all the parts of the mould later today or tomorrow.  Here’s hoping for a a success, but either way I’ll post the results.

M
Title: Re: Fibreglass and things
Post by: Furrari on January 15, 2019, 03:48:44 PM
Demoulding.  A partial success.  The mother mould and the latex mould for the face side have come off a treat.  100%.  The inside, not so good.  In fact a total disaster.  I couldn’t separate the moulds from the patern.  I’m not sure if was a mechanical lock or some other fault, but either way I’ve had to cut it off to save the pattern.
The next version/attempt will be using a part silicon mould.  This stays flexible even when cured but is very much expensive, but thankfully a lot quicker.  I’m also going to print the pouring and rising gates with a taper to reduce the chance or severity of a lock.

No pics 'cos they’re a bit boring.
Title: Re: Fibreglass and things
Post by: Furrari on January 16, 2019, 11:24:04 AM
Further investigation of the problem with, what I’m calling the Mk1 mould, seems to be a mechanical lock.  Although I set the pouring gate and risers accurately at the latex stage it looks as though they’ve moved during the fibreglass stage so I won’t be using this method again.

So what am I going to do? 
I think I’ll use silicone pouring resin instead.  Much more expensive but in light of the previous failure it stands a greater chance of success.
First job is calculate how much resin I need.  Simple job, just measure the size of the pattern (the main part of the calipurr) allowing about 10mm thickness over the whole area. The SG of silicon rubber is about 1.1.  If it’s not enough the cure time will allow me to mix more but you need to allow for it when you estimate if you’ve got enough.  No FG will be required as a top, foam board being enough but you still need a pouring gate and risers.  I’m going to make these bigger (diameter) than before and out of something flexible. (Hose or nylon 11 or12).  This won’t stick to the silicon so they can be removed easily once the silicone has set so there won’t ( I hope) any problems with mechanical lock.

More after the Mk2 cast.

(Edited).   This works out at about 3.5 litres.  That’s a lot at about £18.00 a litre.

M
Title: Re: Fibreglass and things
Post by: Darren on January 16, 2019, 05:55:31 PM
this you tube channel might help with latex things, an interesting channel anyway
https://www.youtube.com/channel/UCfaq-2udXbx8BNbuzRvc5sg?pbjreload=10
D
Title: Re: Fibreglass and things
Post by: Furrari on January 17, 2019, 03:10:54 PM
Silicone ordered.

I have a couple of old silicone moulds I don’t need anymore.  While you can’t recycle silicone rubber back to its constitutant material I read somewhere ( almost certainly YouTube) that you can mince it up and use it as a filler.  As this part of the casting won’t be seen on the finished job if the surface finish is not 100% it won’t matter.  I don’t have a mincer in the garage so I borrowed Management's food blender from the kitchen.  Well it does chop up (most) of the silicone to a small crumb size but what a mess it makes trying to get the finer parts of afterwards.  What I should have done was wait until the weekend when she’s out at a cat show. 
Anyway I now have about 1/2 a Kg of silicone crumb to save on material.  On with the show.

Thanks for the links Darren, I’ve watched all Smooth-On videos before but all the vids seem to cover the easy stuff and not bother with the hard, unusual jobs.
Title: Re: Fibreglass and things
Post by: Furrari on February 18, 2019, 11:30:52 AM
Silicon in and poured.  Mother moulds layer up.  Upper and lower sections separated.  Packers placed on the not required flat bits. Mould release put on.  All bolted back together.

Now comes the bit I’m most concerned about.  It’s quite a big job to cast.  I’ve had problems in the past due to the PU resin setting too quick so I’ve got some slow setting PU.  This takes 7 to 8 minutes to set. 

whish me luck.
Title: Re: Fibreglass and things
Post by: Furrari on February 18, 2019, 05:47:52 PM
Demoulded the casting.  Looked good but close inspection showed it’s far from perfect.  Most of is excellent but at one end there are a couple of places it’s very thin and in one area it ripped.  It’s now back in the mould to fully cure.  The problem is that the moulds have to realign within one millimetre over a distance of 400mm and it’s latex and soft silicone rubber.  I’m not going to give up on it yet.  Tomorrow I’m going to see if I can put a layer of PU and FG mat on the inside where it’s thin.  As the latex mould has survived I’ll also try FG on the inside of that, maybe with a coat of gel coat on first.

I can’t think how to align the moulds better as any packer I use will show on the surface but I suppose a PU packer might work.

Oh well put it down to experience and learn by the mistakes.  No pics as it looks just like the original did except it’s black.
Title: Re: Fibreglass and things
Post by: Furrari on February 21, 2019, 12:14:10 PM
So it’s on to plan C (or is it D or E) for the calipurr.

First job was to make some paper pemplates of the shape of the CF I would need.  This turned out to be pointless as once the resin is on you can’t get a big bit of CF in the space you have.
(Edited).  I forgot to say, before you cut the carbon fibre you need to give it a coat of spray adhesive that’s designed to use with CF.  This stops it fraying. ( well, more or less).

I gave the latex mould three thin coats of yellow gel coat (clear with a 10% pigment) and it’s very YELLOW.  The instructions I’ve seen say .5mm thick.  That’s easy on a large flat surface but not inside a mould 80mm side at is widest and 80mm deep.  I just did it until the latex was covered.

When the gel was at stage B (tacky but doesn’t come off on your finger) I put on the first coat of resin ( Clear but with a drop of black pigment so I could see where I had got to.). Again when this reached stage B it started to put the CF on.  At this stage I realised that I couldn’t get the templates bits on so I just cut it up.  The thickness was gradually built up.  I was aiming at 3 layers of 220 gsm.  We’ll have to see how that goes.  Finally left everything to cure. 

Checked it a couple of hours later and it it was still very soft.  The problem is one of temperature.  Should be 2-3 hours at 20 C with 18 C minimum,  the temp in the composite shop ( the back of the garage ) is nothing like that so I’ve brought it into the house to cure.  At 18C it could take 24 hours to cure.

More later.
Title: Re: Fibreglass and things
Post by: Furrari on February 25, 2019, 10:11:34 AM
Just an update on the calipurrs.

The resin took over 24 hours to set and another day to cure.  Now that it’s cured it should be ready to de mould but the outer flange looks and feels a bit flimsy.  It’s not needed for the final calipurr but it is needed for demoulding so I’m going to stiffen it up but I need to order some more CF and resin.

The expensive way of doing CF is prepreg in an autoclave.  I think I’ve come up with the essentials of an autoclave although it will only work at room ( we’ll garage really) temp.  More on this if it works.
Title: Re: Fibreglass and things
Post by: kalifornia on February 26, 2019, 05:58:51 PM
Hi Mick

Sounds like you are moving into the adult industry  :D
Title: Re: Fibreglass and things
Post by: Furrari on February 26, 2019, 08:57:31 PM
Kal.  I once did a job for the controls for making rubber goods for sex trade.  It was controlling the rate the wooden torso was pulled out of a 45 gallon drum of latex.

My next call was at a company involved in the nuclear industry.  This job was controlling the rate fuel rods out of a reactor housing.  Same circuit.

The big difference was on used a nail banged in to a beam and the other one used a 190’ tower.  You would think they would use more than a nail in a bit of wood in a nuclear reactor.
Title: Re: Fibreglass and things
Post by: Furrari on February 28, 2019, 12:09:04 PM
Went to London yesterday on catclub business.  We had lunch sitting in a courtyard off Red Lion Square.  Suddenly realised we were dining alfresco - in February.

Anyway onwards with the carbon fibre stuff.   Demoulded the calipurr this morning.  Not as shiny as I would have liked, but a bit of paint will work wonders.  Very solid, well it is carbon fibre.

This is plan D, I think.  These are very solid and usable but I have plans to make and use a heatless autoclave which will just improve the interior finish.  But more on this later.

Just a few of pics of the finished job.

First one is the mould with the yellow gel coat on

Second and third are pics of the demoulded calipurr.
Title: Re: Fibreglass and things
Post by: Furrari on February 28, 2019, 12:57:32 PM
Nigelhob.

Tried to send you a PM but can’t get through.  Can you PM me please so I can reply.

M
Title: Re: Fibreglass and things
Post by: Furrari on March 01, 2019, 11:10:03 AM
Well that’s more or less the end of the calipurr project ( for now).  The aim was to make a replacement calipurr for the one I’ve broken with all the pot holes we have round here.  If you’ve been following this bit of the fibreglass and things thread you’ll have seen the ups and downs of a very steep learning curve.

I’m still working on the “ autoclave “ idea but this will just be done as and when.  This consists of using the mother mould from “ plan C” as a backing plate and using an air bladder to push against the wet carbon fibre consumables to remove the excess resin from the lay up.

I won’t be fitting the new calipurr until after Stoneleigh so anybody who wants one can see what they will get but I have plenty of other work in the meantime.  The next bit is making the engine bay a little less kit car/ Mercedes like.  This work will be back on the Furrari build section as there is no CF or FG involved.
Title: Re: Fibreglass and things
Post by: Furrari on March 06, 2019, 11:20:52 AM
The existing calipurrs just have a a Ferrari and a Brembo sticker on.  When I did the engine cover I “cast” the Ferrari logo onto it.  Lot of work but it does look good.  Long term I’m thinking about making the calipurrs with with “Ferrari” cast into them.  Would be a lot of work, but I learnt a lot making the engine cover and plan D on the new, CF calipurr.  Would it be worth it?

What do you think?    Answers and comments on a five pound note please.

I forgot to mention.  We’re having the road resurfaced.  Well I think they are.  They may just be planting some new, baby pot holes to be harvested later.