That was a year that was..

[Bfg]

And then..  for just a couple of hours today . . .

  

^  'Surfacing tissue' .. is glassfibre on a very fine level. It is particularly useful for working into tight corners as well as for preventing print-through of coarser glass fibres showing through on the finished (generally outside) surface.  As you can see it literally has the thickness of a single thin layer of tissue, but as I say those are glass fibres rather than paper or cotton.  Do NOT use as toilet paper !!!

 

^ I've only a small amount of this tissue left over from previous jobs, so I'm using it as a first layer in the rain gutters and all around the edge. It's fineness helps avoid air bubbles in such awkwardly tight corners.  I used a mix of catalyst in the resin which, within the warmth of the polytunnel, cured quickly.  This in turn meant I could get on with the next layer without that being disturbed . . .

   

^ Like the surfacing-tissue, chopped-strand-mat is also made up of fine filaments (drawn fibres) of glass.  And likewise they are each held together (for ease of handling as a sheet) by starch. This goes soft and washes away in the resin - so the glass filaments laid on the job can take to the required shape even if like this Surrey top lid the shape is a compound surface (it doesn't matter whether that is convex or concave, conical or a tube).  For ease of handling I chose to fibreglass the mould in three strips, with a hard cut straight edge first aligned into the rain gutter, but with it not long enough to come up the other side yet. 

  

^ The surfacing tissue, because it's so thin, can easily be wetted out with the resin from the outside. However as thicker glassfibre is used.. then it's usually quicker and easier to paint the wet resin onto the surface first, and then lay the glassfibre mat onto that, and then to apply more resin on top.   Once laid - the important task is to squeeze the air out from inbetween all those glass fibres.  The brush action is one of stippling ..so as to not drag and displace the fibres.  On flatter surfaces I apply the resin with a brush, but then prefer to use a paddle wheel ..which rolls across the wetted surface. This pushes the resin into the glass mat.. which at the same time displaces the air.  The action is light ..rather than a lot of pressure.  Many amateurs try too hard, but if you watch someone with experience they'll wet the surface out and then move on to the next patch, and then return to the first area of work ..when the resin has by itself mostly soaked in. 

The thoroughly wetted-out glassfibre becomes more translucent and takes on the hue of the catalyzed but uncured polyester resin. In this case the resin is tinted blue, so it's easier to see what your doing.  I have in the past used (and generally prefer) green tinted resin, and even pinkish coloured resin which was specifically intended for mould making.  As it cures, the colour will change to a sort of cardboard colour.  Opaque pigment can be added to the resin but that just makes seeing what you are doing all the more difficult.

   

^ a strip of glassfibre to run up the outside flange of the gutters ..and the job for today is done.

Yes.,  just a single layer for today. I don't want the mould to pre-release from the pattern which can happen if too much fibreglassing is done too soon.  This type of fibreglass resin will want to shrink by 1 - 2% as it cures, and so letting this thin layer cure first means that it internal stresses are too small to pull it away.  Too thick a layer of fibreglass will cause the panel to misshape, as its exotherm (byproduct of the curing process) warms everything up too much.  No, I'll let it cure overnight and then apply some more when this polyester resin well set and more stable. 

Pete

 

[Badwolf]

Pete BFG - This is a really interesting tutorial. It deserves a thread all of it's own for ease of finding for the future. Waiting for the next bit.

[Bfg]

On 09/06/2022 at 04:58, Mathew said:

As that is the mould for your top are you going to bond some timber to make it stronger for your process.

For a flash mould where just the top skin is required ..and the moulding's exact width, length or curvature is not essential - that'll not be necessary.  I'm about to give the mould just two more layers of the lightweight (450g/m csm) glass mat and that'll do.  This mould will probably be no thicker than the final moulding taken out of it.  

I'll most likely keep it 'in the loft' ..just in case I loose or damage part of the lid I make, so it remaining compact will be an advantage.  If I were to bond-on a base structure, then the mould's skin would have to be thicker and allowed to cure for a good while before any timber was added ..so as to prevent localised sinkage under the timber (caused by its attaching grp also shrinking by 1 - 2%).   An alternative would be a deep perimeter flange,  ie., four sides of a box around (under) the mould, which would only require local to the perimeter extra mould thickness, but still the additional time to cure.  And although a base / cradle for the mould to sit and be worked upon would be convenient - for the just a one-off moulding - it's more work and time than reward. 

If I were making a mould for production, then it would be three or four times as thick, and allowed to cure for a month or two, and then I'd build an egg box type plywood base box to keep it in shape and as a table base.   Someone else can do that if they want to take over from where I leave off.

Pete

[Badwolf]

When you have finished with it, sell it to the club shop to hire out.

[Bfg]

On 09/06/2022 at 09:44, Badwolf said:

Pete BFG - This is a really interesting tutorial. It deserves a thread all of it's own for ease of finding for the future. Waiting for the next bit.

That's why the cyber gods invented page bookmarks

 

And although posted on Badwolf's topic .. I'll copy it here, for sake of completeness in this 'tutorial' 

 

. . . possibly boring but conversely.. perhaps very-worthwhile reading ..

Some of us are pretty sensitive to the raw glassfibre mat, just in handling the stuff.  Basically that comes down to the dust of broken glass filaments (strands) getting into our skin.  I find that wearing mechanic's grade (thickness and durability) of nitrile rubber gloves* works well to keep that dust from the soft creases of skin between fingers, and a well fitting disposable face mask will help protect you inhaling those fine filaments, but of course even they can be pretty uncomfortable in the heat of the summer.  

Fibreglassing during the coolness of early morning can help with your own body heat and sweat, as of course can be working in the cool shade of a tree or under a temporary cover / gazebo.  

Working under the blazing sun is a frustrating battle to get the chemical mix of fibreglass right anyway - best to avoid.!   Fibreglassing in a breezy place can also work against you as the styrene blows away too quickly and can lead to a very slow, or possibly incomplete curing. However you can do the fibreglassing, in the fresh breeze, and then cover the job over to allow it to properly cure.

When fibreglassing on the boat I usually wear a disposable protective overalls (the white ones with built in hood). They are surprisingly robust for what appears to be paper, and tears can be patched with gaffer tape.  Because they are reusable many times over, they are not expensive. Naturally when removing them, take care not to shake the dust off in your or anyone else's air space., nor to turn the things inside out, whereby that dust gets inside the suit ready for the next time you put it on.   Wearing just underwear in them, means they are not overly-hot in the summer.    

Obviously it's best to handle the raw materials carefully (deliberately / slowly) to minimise shaking the dust into the air and over your skin, and this included subsequently shaking your work clothes of the dust.!   Do that outside, away from others and in a breeze ..with the clothes downwind.  In short be conscious of the fact that it's glass filaments you are handling. Nothing to worry about if you treat it with respect ..but it's not something for small children or pets to be playing in or sniffing at. 

Cutting, drilling, grinding, or sanding cured fibreglass gets that glass filament dust in to the air, onto our skin (inc. face n' neck) into our hair and over / into clothes. It also goes over everything else in the garage / work space.   Same precautions are necessary ..starting off with slow speed cutting to lessen its dust and an old but well-filtered vacuum cleaner (with its out-blowing-air pointing away from the job.     

Wear a face mask as you dust nearby surfaces and sweep up after the job, and please bag the rubbish.    

* Sainsbury's sell blue rubber kitchen gloves, which cover your wrists too, and come in a good range of sizes ..even up to BFG.  They are very good and can even withstand a quick wash in acetone (then quickly rub dry on a cotton cloth).. so are reusable many times over.  

Tip..  glass filaments (rather than actual splinters) in sensitive skin feels like a prickly rash. Do not scratch.  They are very easily removed from the skin (such as your face and neck, the back of your hands and forearms) with a damp sponge and no soap.  Simply draw the damp sponge (a washing-up sponge works great) over the surface ..and the friction in the sponge does the rest.  Wash / rinse the sponge out under running water and repeat.  

Some folk suffer from skin reactions and respiratory discomfort from the chemicals.  Polyester resin is not so aggressive but its catalyst is acid., so when mixed with the resin it can be uncomfortable for some.  Most of us won't have much of a problem with a little splatter here n' there, or when our gloves tear.  But don't leave it on your skin for too long. Have a roll of clean tissue (kitchen roll or mechanics paper roll) close by for when you need it. Clean acetone is most effective in its removal and although the skin can deal with being quickly washed in the stuff - DO NOT get it in your eyes - it stings like anything.!  Dosing with lots of clean water is the quickest way to alleviate that.

Lungs don't cope very well with the chemical vapours, but I've always been fine in a suitably ventilated / large enough space.  However, within the confines of a boat, I've often needed an electric fan blowing towards my face.  Turn the fan off once you are done, so the fibreglass can properly cure in the heat and in its own vapours.   Btw. Those vapours also permeate clothes, so others can smell it on you, and like a good curry it will be on your breath and come out of your skin ..perhaps for a day or three ! ..if you've been doing a lot within closed confines.      

Epoxy resins are generally worse. They also wash off (while still wet / uncured) with acetone, and for me is no worse on the skin than polyester ....but others have been known to suffer a serious reaction and been rushed off to hospital ..so it's best to avoid skin contact altogether.  Personally my respiratory system doesn't cope well with its vapours.  When painting-to-seal the water tanks within my boat with epoxy products - I needed to wear a professional full face mask, with spirit-vapour / virus-quality filtration.  Once fully cured, the epoxy-sealed water tanks are used for potable (drinking) water.  

Body filler / bondo - is usually a fast-curing polyester resin mixed with a bulk-filler powder.  So treat that the same as above polyester-resin.  NB. the bead of catalyst you add to that filler (from the tube) is likewise acid.  Sanding that filler creates a lot of dust, which is not good in your lungs or eyes, but rarely triggers a medical reaction.  

Bridging filler - is usually a fast-curing polyester resin mixed with chopped filaments of glass.  So treat that the same (and its sanding) as above polyester-resin fibreglass.  Again, the bead of catalyst you add to that filler (from the tube) is likewise acid.

Epoxy Body filler and water-proofing / barrier paints - is more commonly used on boats.  I like them because unlike polyester - they are an effective water-proof barrier (polyester is, but epoxy is not hydroscopic). The filler also has noticeably less shrinkage as it cures.. so usually one-fill is enough (and the job was much quicker than going around again).  I used epoxy filler to repair crazing on the deck of the boat for these reasons. And epoxy based paints in the water tanks, bilges and under-the-water-line places of the hull, rudders and keels. I also used epoxy body filler on the 1970's Citroen I restored.  Again similar health precautions are necessary as for epoxy resins, although once cured a person having a reaction to the chemical is probably unlikely.  Likewise., Araldite and other Epoxy based glues adhesives ..although generally they are used in such small quantities as to not cause a problem, someone who is specifically allergic to epoxy resin may similarly suffer discomfort if they get too close. 

Nail-varnish-remover used to be a weak mix of Acetone.  I don't know if it still is, but if so then it's useful to have a bottle kicking around, just to wipe finger tips and to clean small tools used in the application of such resins, fillers, glues.  

Live long and prosper

Pete

[Bfg]

 

I'd fibreglassed just two more layers of 450g/m2 csm (chopped strand mat) on the surface, before I went out for lunch on Thursday, and then trimmed off the sharp fibreglass bards around the edges a couple of days later. 

And then today, I was moving it around.. into the sunshine, and noted it coming loose from the steel panel. 

^ it didn't take much finger and thumb to open up the gap you see above, so I thought it best to now gently pull the mould off. . .

 

^ I wasn't planning on releasing the mould just yet, but it being partly on / off wouldn't be good ..because the heat, or cooling, from the steel panel would no longer be even (with some places touching and others not) so it's better to let it be free.   I figure its final curing might also be better achieved with both faces open to the air,  but it does now need to be carefully placed ..as such a lightweight mould will be prone to twist &/or flattening out.

Can hardly say 'Job done' because I just gently peeled the two apart ..tbh I'd have more of a struggle opening a packet of peanuts.!   . . . but still I'll give myself a little   for the mould not having stuck to the filler I'd used to fair the pattern. 

Bidding you a good evening,

Pete

 

oh yeah . . .

       

^ this apartment's bedroom has 'period' wallpaper befitting a 1970's semi-detached-suburbia home's lounge (..1970's may well be the last time this place had a make-over) ..so this 60 year old lid is now an exclusive  wall-sculpture worth tens-of-thousands.!   Yeah I know., abstract art is not to everyone's taste - but then it may be celebrated ..simply as something that mostly only us bachelors are free to do   

 

[Badwolf]

Just love the wall hanging and ultra impressed with the release of the mould. Keep going... I need your inspiration 👍👍👍

[Bfg]

^ Likewise keep it going  ..you are inspiring others 

 

This afternoon I cleaned out the residue PVA and wax that had transferred from the pattern . . .

^ surprisingly to me, a little of the red paint from the pattern transferred. No worries, it was soon washed away with a little soapy water and a light rubbing over with 320 grit wet n' dry.

I then spent some time refinishing the mould edges, which is to serve as an extra 1/4" of flange all around the edge. This will make it a little easier to laminate / fibreglass the moulding.  At the same time I trued up the rain gutters and the front n' rear edge detailing of the steel pressing ..mostly working by hand (files, wet n, dry and a rubber sanding block) rather than with power tools, after all we're mostly only cutting plastic (albeit with nasty glass filaments).  

^ flatted with 320 grit wet n' dry, mostly on the curved back of the rubber sanding block.  

Although overall fairing (true curvatures) of the pattern is the same as finishing bodywork, the smoothing process is simpler with fibreglass mouldings..  Firstly sand off the high points off the pattern.  Take a mould off that ..and what were pits, pinholes, open blister pock-marks or chips in the paint, &/or sanding-down scratches in the pattern become high spots and fine ridges in the surface of the mould.  Carefully sand (wet n' dry) those off.. and the remaining surface is mid-level and now smooth.  Any indents or scratches in the mould will likewise reverse to be high spots and fine ridges in any moulding ..and they can likewise be easily cut back to the smooth mid-level. 

And just because I could, I did have a quick looksee . . .

^ despite the flanges being a little longer all around it looks a pretty good fit.   I could of course refinish (smooth &/or vinyl cover) the outside face and be done with it.  I'd retaining the smooth finish inside, but loose the definition of the steel panel I wanted externally.

With the inside surface exposed, the mould presently sits in the sun to cure some more.

Pete

 

 

[Badwolf]

Looking really good. How long does it need to cure for maximum strength?

[Bfg]

16 hours ago, Badwolf said:

Looking really good. How long does it need to cure for maximum strength?

Thanks,  Good question, and the bottom line answer is that I don't know ..with the resin I presently have.  Usually in this sort of weather I'd be thinking about a week. But for whatever reason this particular 25kg barrel of  'general purpose polyester resin' seems to rather like gelcoat insomuch as it appears to have set with the catalyst in normal times, but it does not really cure for ages ..insomuch as the surface remains tacky for a long while. 

I used it on the lid of my trailer box and after many months that's now fully cured and turned cardboard brown colour.  This mould is very much thinner and now that I've opened the inside surface it can can dissipate its styrene from both faces, but I don't know how long it'll be before I'll feel it's fully cured.  Its cyan blue colour has turned to be more of a sage green, and the outside surface is far less tacky, but still I'm not confident that it's ready to be used as a mould - without fear of the moulding not being able to be released.   Hopefully another week's patience will be rewarded by things then going well.   

As a general purpose resin it may be a good thing.. to remain tacky for longer, so that subsequent laminates (perhaps over several days, can be applied and be assured of a good chemical bond.  On the other hand, it remaining sticky is a real pain when the laminating is done and you just want to get on and finish the job. As I found with the trailer's lid as soon as you try to sand it, the paper clogs up. 

I'll let you know,

Pete

p.s.  as an aside epoxy resin doesn't cure to full strength until cooked in an autoclave (sailing boat masts and wind vanes are cooked to ensure maximum strength is achieved).  Boat hulls are cooked under a tent, or with electrical elements built into the mould, but they rarely achieve absolute maximum.  But then, even its less cured state, it's generally regarded as being stronger than any polyester resin. 

The strength of the glass within the laminate is of course the same, save that epoxy laminates are usually of woven-glass-fibres, or stitched together uni/ bi / tri-directional glass strands ..rather than chopped-strand-mat.  But then woven glass and uni-directionals can also be used in polyester laminates.  

[Badwolf]

Thanks for the guide. I had always assumed that when it went hard, that was it. I had no idea that we were talking days/weeks to reach anything like full strength. I still remember daubing David's Isopon over my first car, walloping chopped strand matting over the top and daubing some more resin on the top. Gone hard?? Filler, paint next day job done. Wow, was I mistaken...but that was 40ish years ago.

[Josef]

I too have very much enjoyed reading about fibreglass methods! Will be squirrelling the information away for when it comes in handy (third attempt at a handbrake gaiter support for me I think once the paper one eventually disintegrates) and looking forward to seeing how the production of the actual roof from the mould comes along. 

[JohnD]

There are two kinds of gelcoat, or rather gelcoats for two purposes - layering and topcoat.

Layering is to build up a thicker surface.  It's just like resin you would use with glass reinforcement.

Top coat contains a wax, that floats to the top and forms a coating to exclude air and oxygen.

But even layering will harden, eventually, as long as the right amount of polymerising agent was added, and thoroughly mixed.  The last is another reason to make up resin in small quantities, and to MIX, MIX, MIX, before using it!

 

 

[Bfg]

The gelcoat being finger tacky until air is excluded or it's given time to fully cure is not a problem, that just aids the chemical bond between it and the laminating resin.  I'm only having issues with this laminating resin being tacky for so long.  I've not had this with the resins I've used before and so I wonder if they've sold me casting resin ?  ie., what's used for things casting like chess pieces.   In any case I'll not be buying it via e-bay again, I'll buy it directly from the workshop store at the marina.

One of the most important things with gelcoat is to add the catalyst and to mix it with thoroughly ..And then to transfer the catalysed gelcoat to another (clean) pot and give it another good stir.  Never do the mixing with the paintbrush, and don't even brush the surplus off the mixing stick.  The reason for this is that the gelcoat at the very bottom, around the sides of the pot, and that on the mixing stick, &/or within the bristles of the brush (if you've used that for mixing) is likely to have less catalyst.  It will go off eventually  ..but in the meantime - if you laminate over uncured gelcoat, it will wrinkle-like craze.

Pete

[Bfg]

Not a lot happening on the Eastern front. The Surrey-lid's mould is still curing as i await fresh gelcoat to come in ..and, as planned, I've diverted my attentions to working on the boat. . .

 

^ the 30ft catamaran is mine, and she was first commissioned in 1972.  I bought her knowing structural work was required, and I've done 99% of that now, so it's 'just' a case of replacing the systems, putting together the new rudders I've made, adding safety lines, refurbishing or replacing the rig and most likely all the sails, and recommissioning or replacing the outboard motor.  Well that's not all but they're the things that spring to mind.

 A few years back, the boatyard's  'dry-storage' park flooded (5ft deep) in salt-water, whereby things that should have been kept dry got wet & very muddy. A lot of stuff and tools of some value were destroyed.  Nevertheless, I had planned on getting back to work on the boat in April ..two years ago.  But just then strict Covid restrictions were introduced and I wasn't allowed (..even though I would have been working on my own, access to the boatyard was closed).  And then just for fun I was also told to move out my home.  Moving out of a house and into an apartment didn't help because much of 'the stuff' off the boat had been stored at home, and so it had to come back.  Because that was done in haste, and again around Covid restriction, those things were never sorted.  I then bought Katie.., a tidy and driveable car.   Well as you know "there's always a few jobs to do"   ...now, a couple of years later - it's time to move on.

You'll be glad to hear that I'll not be boring you with the tasks I'm doing on the boat, save to say that it will occupy the rest of this year (..at least ! ).  I've come around to the boatyard in the TR a couple of times, but usually I'm in the old Chrysler Voyager workhorse that I drive as a (20 y.old) modern.  The boatyard is either dusty or wet.  On our Katie's first visit it was the former, and on Sunday afternoon, when I came down to do just a few hours work it was mostly dry ..but with heavy rain showers. . .

^ although the Surrey back-light is still on, without having a workable infill panel - we managed just fine.  

Still, the drive back home was very pleasant in the freshly cleansed air,  and when I got home it was still a glorious evening. . .

  

Pete

 

 

[AlanT]

On 21/06/2022 at 12:51, Mathew said:

So a tow bar on the tr for the boat next? Good to see katie out and about.

Why not combine the two as per Top Gear? 

[1969Mk3Spitfire]

On 21/06/2022 at 12:28, Bfg said:

........the 30ft catamaran is mine, and she was first commissioned in 1972.  I bought her knowing structural work was required, and I've done 99% of that now, so it's 'just' a case of replacing the systems, putting together the new rudders I've made, adding safety lines, refurbishing the rig and most likely replacing all the sails, and recommissioning or replacing the outboard motor.  Well that's not all but they're the things that spring to mind.

As a fellow sailor, that's one helluva project. Best of luck, fair winds.

[Bfg]

^ impressive how someone has managed to plug the holes in those Top gear cars.  I would have thoroughly enjoyed doing that challenge.  

Hey-ho back to my own reality, in a polytunnel ..

Well, I got the new gel-coat and surfacing tissue in and so could proceed with work on the Surrey-top lid on Thursday. Tbh it didn't go well, perhaps because I was trying to get things done in a rush before I went out at midday.  I didn't make that appointment because me be me.. I first wanted to do a little more flatting on the inside of the mould.  Looking afresh at the inside surface - I decided to rubbed it down some more with 320 grit wet n' dry and then to go over it again with 600 grit.

That done I was behind schedule by an hour, but still keen to get the job done and to go out. My back-ache, which had been giving me serious jip on Wednesday, had abated quite a bit and so this rubbing down, followed by a couple of very vigorously worked-in (Mirroglaze) wax coats (..to seal pinholes and hopefully prevent the mould and the moulding-panel chemically bonding together) gave it plenty of stretching exercise. 

^ I then wanted to fill in a few blemishes around the edges of this mould, for which I used Plasticine (kiddies modeling dough, which is better for this work than than any subsequent clone I've come across (such as Play-Dough).  It was just applied with a metal paint scraper, and it does not go hard, but in the above instance it reshaped the very rear-end of the rain-water gutter. 

Next then, as previously described was a couple of coats of the PVA release agent.  By this time of day it was reportedly 23-degrees outside the poly-tunnel ..and much warmer within. The weather forecast has said 40% chance of thunderstorms, but that never happened here. Instead we had 98% humidity.  My face and hands were literally dripping with perspiration. Anyway the conditions were not favourable for coating the mould smoothly. And the brightness of sunlight, although diffused through the clear plastic polytunnel, onto a white mould made things so much more difficult..  

I gave the mould two coats of PVA and then looking at it.. phoned my friend to advise him that I'd not be able to meet him for lunch.  Instead I washed the PVA off (fresh water and soft cloths),  dried the mould,  and erected a dark-cover over where I was working (..so that I might better see what I was doing).  I then gave it (the mould) another two coats of Mirroglaze, repaired the shape of the now dented plasticine filler, and eventually got to gelcoat the mould (for what will be the outer skin of the moulding).

      

^ The boat-yard was kind enough to provide (sell me) 1/2-litre of clear gel-coat (ie. without pigment) in an ice cream tub I'd provided. It comes as a vibrant but translucent magenta-pink colour, but as you can see when catalysed & painted on - it is all but clear.   I have never liked dark interiors to my cars, and so I wanted this lid to be as translucent as possible. It will probable look 'terrible' (..please feel free to substitute your own word there) and will end up being painted, but I thought I'd at least give it a go.

That was on Thursday. And then yesterday I gave it a layer of surfacing tissue ..bought from the marina's chandlery (..shop by any other name, with yachty-inflated prices) . . .

^ Like most other things - there are differences in supplies, and this 'fibreglass tissue' ( 30g/sq.m ) was tight and heavily starched. That may be fine for flat surfaces (..which are generally avoided in fibreglass work) but for compound curves - it was a right nuisance.  In the bottom-right of this photo you can see how loose my old-stock tissue had been, conversely the new stuff ..which I'd specifically had to cut to the curved shape around the front of this roof, was like a regency gentleman's starched collar. When wetted-out with resin - it was of course much more flexible ..but still it's brand I'll avoid buying again. 

^ Anyway, one layer of tissue was applied all over and then another layer all the way around the edges to help create the tightly defined shapes from the steel lid's front edge roll, the side rain-gutters and the joggled-step across the back edge.  Again it didn't go on particularly well but it'll have to do.  That was left to cure before the next layer of glass-fibre was applied.  Note the jury rigged sun shades !

and so onto today. . .

^ with the first, surfacing tissue laminate, mostly cured - the chopped-strand-mat (glass fibres) was layed out and roughly trimmed to shape.  Again this glass mat is starched flat, and to fit it to the concave shape I hand tear down from the edges (like a seamstress would cut darts in a fabric which is to fit neatly around a body or limb). Those loose fibre edges can just be seen overlaying others. When wetted-out with resin these hand-torn edges will hardly be seen, whereas scissor cut edges would have shown pronounced edges.

All the glassfibre to be applied (..one layer overall, plus two additional layers around each edge, and also a centre strip) were prepared ready to pick up and bond in place.  Around the edge, I prefer a scissor cut edge outside and a hand torn (feathered) edge to the inside.

   

^ job done for today. The top skin of this lid moulding is mostly there, presently it's very lightweight but with edges reinforced. Down the centre you'll see that the additional layer was both scissor cut and hand torn.  The scissor cut edges were overlapped and, even when laminated, are more clearly defined than the hand torn (feathered) edges to either side.  The surfacing tissue is of course under all of this and was used where there's detail definition and to cling to the the mould's edges  ..whereas as you can see in the top RH corner of the inset photo, the heavier chopped-strand mat tends to stick out rather than cling to a tight radius.  I've used blocks and packing to try and hold those edges in tighter to the rain-gutter, but I expect to have to do some reworking of those.

That's it for today, now I need to go grocery shopping. (I'll re-read and check / correct my typos / grammar tomorrow)

I bid you a pleasant evening and a good weekend.

Pete      

   

 

[Bfg]

Good afternoon all..

^ As the moulding cures a little more in the polytunnel's warmth under the honeysuckle ..and for just an hour or so this Sunday afternoon, I did a little more, starting with my removing the windscreen-frame's cap rail. . .

^ This is the TR6 type cap rail, without  a front overhang for the TR4's fabric Surrey top (as that initiates wind-noise above 50mph), but with dip-recesses for the 90-degree-turn lever-arm securing clamps (in these photos the masking tape is covering the holes for those).  I've waxed it a couple of times with Mirrorglaze and filled over the rivet / screw holes with raised blobs of plasticine, and then given it a couple of coats of PVA.  The plan is to take a moulding directly off of it and to bond that to the underside of the top-skin I've made.

  

^ Similarly I've masked up the rear window seal of the Surrey-top backlight, over its forward facing vinyl-wrapped weather-seal flange, and also covered over the surrey-top attachment holes.  I've used a polythene-sheet to protect the car's interior and rear wings from drips of resin. And again, a couple of coats of Mirrorglaze and a couple of coats of PVA release agent.

  

^ each are now clear gel-coated and set aside to cure. 

I'm winging it, so I look forward to seeing if this lightweight version of a hardtop Surrey lid, when it's all together, will work.!?

Pete

 

[Badwolf]

Absolutely fascinating.   👍

[Bfg]

   

^ Surfacing tissue applied, ready for tomorrow's heavier glass-fibre laminates.  Again, this very fine glass-fibre 'tissue' is being used as a first layer - because it's better able to follow the shape over hard corners and down into local depressions in the pattern.    

Often cars and hardtops made in fibreglass have very rounded panel and edge definitions ..and so look like fibreglass cars.  The objective here, is to make a Surrey-top lid with the edge-definitions of a steel or aluminium panel ..which to my eyes looks more authentic on a a 1960's classic.  Only by physically touching the panel (..its warmth and its duller sound) might another person realise that it is not made from metal.

Having said that.. I'm blowing it - by trying to make it semi-translucent !

Hey-ho that's me .. trying to achieve more than is possible with the limited resources I have.  ..But if anyone has a large enough vacuum forming machine and the right colour of ABS sheet.. then please drop me a line.   

Pete

[Bfg]

Not a whole lot to report on, not least because I've been lazy these past few days and have enjoyed reading a book (well., half way so far).  That's not something I've done very often in my lifetime, mostly I think because as a dyslexic my reading ability has always been incredibly slow.  However, as I've written more over these past few years, it seems to have greatly improved.  Still, aside from a dozen or so car orientated books, I guess I've only ever completely  read a dozen or so others ..including the bible and those required in schooling, so it is enlightening and refreshing to now be able to read ..and to let my imagination paint the pictures. 

My reading this book started when I was aching so bad, in my lumber and sciatic nerve regions, that I skipped getting on with the workshop tasks in hand.  I placed loose chocks under a chair to tilt it back and that helps with the discomfort, and the enthralling tale has on the whole otherwise kept my mind distracted. That is until I try to get up ! 

Anyway, aside from that, I've not done a whole lot because the temperatures in this poly-tunnel result in my perspiring to the point of blotting vision (..the inside of my spectacles) and literally pouring out of the short nitrile gloves I'm wearing for fibreglassing ..whenever my hands are upturned.  A weak excuse for sure.  But this is all I've done since Sunday . . .

   

^ fibreglassing the windscreen header-rail proved to be right pain in the xxxx.  That of course is my fault because foolishly I was trying to fibreglass a lightweight, long and unstable piece of aluminium ..which moves around as I tried to work the resin into the glass fibres.  In retrospect I should simply have screwed it to a block of timber that could be clamped in the workmate. #2 mistake was in my not extending its edges. This can easily be done with strips of cardboard, or even just masking tape. Then once the surfacing tissue is applied and its resin cured, there there would have been a flange on which the 'flash' (untrimmed edge ..to be cut off) would have laid flat.  As it was., I fought to get the short strands of fibreglass to conform with the short down-turned edge ..and then to keep it there rather than for it to spring back again.  I ended up running around and using sprung clips and battens to hold the edges down, along with blocks and weights.  In short my laziness in preparation, made for far more more work and stress than there ought to have been. Not at all a professional approach and this will yet again reflect in more trimming and rework being required, before the part is usable.    

In contrast, the fibreglass laminates over the backlight's top rail went very much easier. 

 

^ That's better !

Today, I was better prepared, and of course Katie  is making herself useful as well. . .

^ a work-table is quite necessary for marking out and cutting the fibreglass mat, irrespective of the limited work space.  NB. I'm using scissors and hand tearing the fibreglass rather than using a Stanley-knife to cut the glass mat on the bonnet !

 I do try to keep the sticky resin and paint destroying acetone off the car though.  

My task today was to add a backbone spine to the lid moulding being made. The idea being that this will end up as a T-bar, to brace backlight rearwards from the windscreen. And that in turn ought to keep the rear window glass from falling out ..which'll add a little to peace-of-mind when driving along the motorway !  For a lightweight beam I'm using 1" thick 'foam-core' (hard urethane foam ) that I have left over from replacing the balsa-core structure in the bridgedeck throughout the boat. 

^ I've cut a strip, just a little narrower than 4" to go from front to back of the hardtop lid, and rounded its edge corners.  This rounded-edge will be face down in the moulding.  As seen above.. I've bowed the foam to open the pre-cut kerfs (slits) and painted catalysed resin into them, on both sides. 

^ the balsa core was then placed, centrally, over a 6" wide strip of glassfibre, and another lightweight layer of glassfibre applied over the top of it. The kerfs in foam-core are to allow it to conform (under pressure) to compound surface shapes.  On my boat I used a specific purpose polyester adhesive to 'goo' the balsa-core down ..and then used numerous 25kg lead weights placed on plywood boards, which were laid over a part inflated air bed - to hold the core down (the air bed of course complied to the curved shapes of the boat while at the same time applies equal pressure all over).  It worked well.  On this occasion I'm hoping that a wrap around of glassfibre will bond the foam in place, but I still needed to hold it down while the resin cures. I'd preplanned this to use the primitive resources I have to hand. . . 

^ a tubular steel beam (left over from my making a camping-trailer chassis) clamped down at either end to the workmates the hardtop-lid is resting on.  And thereafter packing / wedges between that and battens laid the length of the foam core.   The 1" edge of the 6" wide glassfibre strip that was under the foam core has been lifted up the sides of the core.  Another 1" wide strip of glass fibre was added over those vertical sides and then two more layers of glassfibre (their top edge scissor cut, outside edges hand torn / feathered) placed down the sides and to spread out on the moulding's inside surface. 

I think it went well. !  ..but I'm worried that the shape may be more bowed than it should be.   The pre-planning (unlike my effort on the windscreen cap-rail) paid me back with this task being easy. 

That will now need to cure, before the underside of this 'beam' can be shaped to the two new fibreglass windscreen and back-light cap rails.  And then the bottom face of the foam-core can be fibreglassed over to create a very stiff (..but light-as-foam) box beam.  

As this place is now looking like a fibreglass workshop mess, that walks into my home, I'll now do some tidying up.

Accordingly.. that's it for today.

Pete

 

[Bfg]

Since Wednesday I've continued to potter, between finishing reading the historical novel (..575 pages is something of an achievement for me) and the sciatica, I'm steadily moving along with shaping the lid's fitting structure of the lid to the car.  As it's a sorta bitsy process, I'll try to run through photos as a comic strip ..

 

On Wednesday, I'd signed off after having just bonded and side-laminated the foam-core, which I plan to be a T-Bar between the windscreen and the Surrey-top back-light.  Above  is later that same evening when the fibreglass resin had cured to a hard cheese consistency (ie. before it goes really hard) and I was able to green-trim those edges of the flash.  Timing when doing this is quite critical insomuch as the resin has to still be soft enough to cut with a craft knife (note the angle of the blade as it's drawn along) and yet not be too soft whereby the resin pulls / crumbles off the glass fibre strands ..which then leaves a frayed edge.

   

^ I released (just peeled off) the laminate from the top rail of back-light, which thankfully hadn't stuck to the paint at all.  That fibreglass could then be safely trimmed. 

^ Similarly I released the laminate from the TR6 windscreen's cap rail, for it to be trimmed.  Fibreglass doesn't stick to aluminium very well at all (which makes it a really useful material for quick n' easy moulds when making flanges, fibreglass brackets, etc) ..so I wasn't concerned about it sticking.  However I did have to careful prise it off (with thin wedges / battens of softwood) because the glassfibre laminate had wrapped around the underside edges, and I didn't want to use a power tool for trimming those edges for fear of damaging the (soft metal) cap rail (..which is to go back on).  Twisting the cap-rail & moulding, snapped the bond between the two, so the softwood wedges were mostly to prise the aluminium out ..before I could get fingers in to pull.

    

^ the new fibreglass windscreen cap rail trimmed, ^^ trial fitted,  and then ^^^ (loosely) fitted with the latches.  In the latter two photos the fibreglass piece is sitting on the aluminium cap rail. 

 

^ with both the aluminium + fibreglass cap rails in place, as well as the fibreglass cap rail for the backlight, the hardtop lid (still in its mould) was placed on the car, and marked where the foam core of the T-bar beam needed to be trimmed back.

 

^ with the T-bar's foam core shaped, whereby the lid sat down on the two new cap rails, I closed-in the underside of this box-beam.  The above shows a laminate just wetted-out, but before its side overhangs were stippled (with brush) down to form sides of the box.  Once that was smoothly achieved the wet laminate was paddle-wheel rolled to squeeze the air out from under and between the glass-fibre filaments.

^ while I had the glassfibre out, I laminated three layers over a rolled length of angle (salvaged from the skip).  This is one of two such fibreglass angled-flanges to be made ..which will soon be bonded along the inside of the lid moulding, in place for the door-glass weather-seals.

I've spoken of the foam core, now within a box-section fibreglass beam as a T-bar.  The plan is for that to be screwed to the windscreen header rail and the back-light's cap top rail, and then for the two side panels (over seats) to be qd removable Surrey-lids, that are lightweight and small enough to carry within the car or on a boot rack. To achieve this I needed two more inside edge weather-seal flanges. . .

  

^ hardboard was used as faces to laminate against, and to hold those in place I used blocks, with weights where necessary to keep the pressure on.  You can hardly make it out from the photos but the outside face and edges of those pieces of hardboard have been covered with aluminium tape (left over from when I insulated my container). As previously said, the fibreglass doesn't stick well to aluminium so this tape is a cheap and easily shaped release-face for something like hardboard, which grp would normally stick to with a vengeance. The inset photo simply illustrates my fibreglassing up this flange face, inbetween the blocks.  

When the resin of those first thin layers had kicked off, the blocks could be removed and the fibreglassing of these flanges properly done. . .

       

^ the new flanges have been laminated against the aluminum-faced hardboard formers.  At the front-end ; the hardboard was held against the foam-core beam simply with a piece of masking tape. Further back (where the blocks had been) you can just about make out packers of very thin plywood. 2/3rd the way back are slightly thicker packer pieces, and then right at the back (top of this photo) are 3/16" thick packers.  The reason for this was that back width of the metal hardtop lid, and therefore the mould and moulding I'm now using, was a little too wide for a neat fit against the side notches in backlight frame.  I suspect the depth of their rubber seal was more than I hope to use.  So these packers holding the flange further apart across the rear, whereby I then hope to trim a little of that excess width off the panels I'm making.  It's a risk and a complication, but hey.. if that's what'll be better fitting - then I'll give it a go. 

And that my friends is as far as I've got this week.  Slow progress, but steadily in the right direction.

Bidding you a good evening,

Pete 

 

 

 

[thescrapman]

On 09/07/2022 at 15:44, Mathew said:

A message from pete....

To convey apologies for my absence, to explain that I can no longer post or reply, that a kindly admin is looking into it for me  ...and that the Surrey-top lid I'm making easily released from the flash mould, and since then I've added the front and rear cap rails to it and fitted  the front (TR6 ) latches.

Pete would like to post but due to technical issues that the tec guys at admin are trying to sort out he is unable too at the moment. 

Well we know what the technical issues are, as they have also knocked out my iPad.

Looks like Invision have removed some access to old (very) browsers and / or operating systems.

I have temporarily moved to a slightly newer iPad, and we need to find a way to move Pete on from his abacus now.

 

[PeteH]

Sounds to me like the same/similar issues that come with older versions of Windows, and New versions not running "legacy" software. My Older I-pad cannot run anything above IOS-9.4. and I can only read this Forum, but not comment.

What is about "Techies" that they dont understand "if it works DONT fix it".

Pete