pompeyal - Sorry to read what a nightmare your bonnet mould has turned out to be. :icon_sad:

Unfortunately, I don't have any experience of making "proper" moulds.
( So my use of parcel tape as a release agent is not relevant here. )

However, Viatron posted on his build that he applied 4 coats of this release wax on his moulds.
( Apparently he has used it for years and it always works well. )

https://lh6.googleusercontent.com/-c.../IMG_01235.jpg

Obviously, not much help in this case, but make help if you have other stuff to make.

Good luck, Paul. :)

Thanks Paul, I still have to make the bonnet from the mould so thats the way I will be going for that, couldn't waste another whole day digging out again....

Six coats of mold release wax and for belt & suspenders, spray it with a couple of coats of PVA. Best for a plug for the first release.

Why the PVA surely thats an adhesive?

I believe you use the PVA first to seal the surface of the mould and when dry leaves a nice shiny surface

Prior to adding the wax?

PVA = Polyvinyl Alcohol is a release agent.

Use it after waxing the mold and letting the wax gas-off for about an hour. The PVA is water soluble so easy to clean up.
Check with any fiberglass supply place and they'll have it.
Cheap insurance to ensure a part or mold does not "stick"
Hate it when that happens. I just now finished spraying PVA on a new roof duct mold for an RCR Superlite Coupe. (USA). I have the only mold for that part and the manufacturer gave permission to make them for customers should they desire it. Been playing with fiberglass since the early 1960's. Simply a retired old broke guy having fun!

Everyday is a school day - that makes a lot more sense than using PVA glue then. :biggrin1:

Bonnet continued

Right tried out a few things tonight just to see how it went, VHT Strip Fast certainly lifts the paint into a gooey mess and I didn’t leave it on long then scraped it of quickly, this seems to not have attacked the glass underneath, mind you it wasn’t on long. Cleaned back with spray gun cleaner, “Neogene”, can’t leave that on to long either, that will attack the glass, next put down some Nitromors and a spray of VHT Strip Fast over the top, left for a minute or two then with a soft brush rubbed it around then scraped of the mess, that seemed to work as well so I think about ten hours of stripping and sanding back I may have a workable mould, I will just have to see….

http://i652.photobucket.com/albums/u...t/IMAG2034.jpg

Bonnet continued

Tried out this stuff, worked a treat on this fresh paint but not sure how it would cope with old car paint finishes, will be trying that out later..

http://i652.photobucket.com/albums/u...t/IMAG2035.jpg

I went round covering 300mm squares and leaving for an hour

http://i652.photobucket.com/albums/u...t/IMAG2036.jpg

I continued this until I had removed the majority of the paint, I didn’t try to do too much at a time because it does create quite a mess

http://i652.photobucket.com/albums/u...t/IMAG2038.jpg

http://i652.photobucket.com/albums/u...t/IMAG2037.jpg

I started sanding back the imperfections but forgot to take a picture, shall do that later, I am sure with a bit I work I can recover the mould so I though I would reinforce the edges by bonding on a flange… First I covered around the bonnet opening with cling film and placed the mould over...

http://i652.photobucket.com/albums/u...t/IMAG2039.jpg

http://i652.photobucket.com/albums/u...t/IMAG2040.jpg

Then I cut some fibreglass roving woven tape into lengths and positioned them around the mould…

http://i652.photobucket.com/albums/u...t/IMAG2042.jpg

Then mixed up some resin and applied it to the tape

http://i652.photobucket.com/albums/u...t/IMAG2043.jpg

http://i652.photobucket.com/albums/u...t/IMAG2044.jpg

I will now leave that until it starts to set off then cut some strips of fibreglass mat and do the same.

Bonnet continued

Well the strips of glass have been added and then set with resin, once set I will trim around the flange and get on with polishing back the inside of the mould

http://i652.photobucket.com/albums/u...t/IMAG2045.jpg

http://i652.photobucket.com/albums/u...t/IMAG2046.jpg

Removed the mould from the car and now you can see that I have some polishing to do along with some minor repairs,,

http://i652.photobucket.com/albums/u...t/IMAG2047.jpg

After all your hard work, I really hope the new bonnet turns out the way you want it. :pray:

Good luck, Paul. :)

From where that mould was a week ago you must be pleased and relieved. Going to be worth it by the looks of it.

Thanks guys, hopefully I sould have it sorted at the weekend fingers crossed...

Bonnet continued

Done a few bits during the week for the bonnet, made a pair of bonnet hinges with brackets and a latch pin and bracket, just need to get the bonnet sorted out……

http://i652.photobucket.com/albums/u...t/IMAG2048.jpg

http://i652.photobucket.com/albums/u...t/IMAG2049.jpg

http://i652.photobucket.com/albums/u...t/IMAG2050.jpg

I love those hinges. How's the bonnet coming along?

Thanks Mr Jones, to be honest I haven't touched the car for a month, the son in law collared me to build his workshop with him and its been more like for him, hope to have it finished tomorrow then I will get on and repair the mould...

Bonnet continued
 

Well it’s been a while and a slight stall on the project but I am now back on line, I started assessing the damage to the mould and got ready for the repairs, the main areas for concern were the damaged edges but started filling the imperfections with filler putty

http://i652.photobucket.com/albums/u...t/IMAG2051.jpg

http://i652.photobucket.com/albums/u...t/IMAG2053.jpg

http://i652.photobucket.com/albums/u...t/IMAG2054.jpg

http://i652.photobucket.com/albums/u...t/IMAG2055.jpg

http://i652.photobucket.com/albums/u...t/IMAG2056.jpg

http://i652.photobucket.com/albums/u...t/IMAG2057.jpg

http://i652.photobucket.com/albums/u...t/IMAG2059.jpg

http://i652.photobucket.com/albums/u...t/IMAG2060.jpg

http://i652.photobucket.com/albums/u...t/IMAG2061.jpg

http://i652.photobucket.com/albums/u...t/IMAG2065.jpg

Before going too far I had to pay a visit to my resin supplier and had a chat about what I had done so far and he warned me against using filler because there would be a good chance the gel coat would stick to it and recommended that I should use gel coat for the repairs, rub that back and then flat and wax at least five coats, then apply PVA,…. Hmm more work then so back home and start again..

http://i652.photobucket.com/albums/u...t/IMAG2066.jpg

First things then, a fresh coat of gel coat

http://i652.photobucket.com/albums/u...t/IMAG2068.jpg


Then built a dam around the edges with plasticine where they had been damaged and in filled with gel coat

http://i652.photobucket.com/albums/u...t/IMAG2069.jpg

http://i652.photobucket.com/albums/u...t/IMAG2070.jpg

After that removed the dams and cleaned, now to rub it all back flat…

http://i652.photobucket.com/albums/u...t/IMAG2071.jpg

Then 6 coats of wax, one for luck…

http://i652.photobucket.com/albums/u...t/IMAG2072.jpg

Then the PVA application..

http://i652.photobucket.com/albums/u...t/IMAG2073.jpg

http://i652.photobucket.com/albums/u...t/IMAG2074.jpg

And now I have committed to the bonnet, first coat of gel…everything has now been suitably crossed and in hope all goes well

http://i652.photobucket.com/albums/u...t/IMAG2075.jpg

Nice to see you back, thought son in law got you building a house as well as a workshop!! Lol. Fingers crossed here too, good luck.

You know when you get asked to help and then end up doing it with a little help from the person who asked, that was the workshop build, anyway I am back underway and thanks....:icon_wink: