1st Nova & the unregistered one

[islandman]

Hi Dave,
Sealing the flange with candle wax, that's not one I have heard of are you melting the wax on the joint? and then cutting any excess? does the curing process not produce enough heat to melt the wax?

Dirk

Yes I basically light a candlestick and hold it over the flange joint to let the wax melt into the gap between the flange and the part. To make it easier I turn the dash and rest it at various angles so I can easily get the wax to drip in the right place. While the wax hasn't fully hardened I scrape off the excess with a plastic knife or wooden lollipop stick thing (actually its a doctor's tongue depressor). This helps give a nice slightly concave edge.

The hot matt doesn't seem to melt with the wax as this is the process I used last time. Also remember that the Gel Coat goes down first and that isn't that thick and doesn't generate that much heat. Once that its semi-hardened it doesn't really matter how much heat is generated with the thicker layers of matt as the wax is already sealed in with the Gel Coat. Then when I put the mold parts back together again I use the same process and fill the mold gaps with candle wax also to minimise Gel Coat flashing lines.

I got this tip from Brett on the Sterling site, he does some great work. Worth a look at his thread.

[Gaisa]

Enjoying the project so far, sorry to hear about the glass moving and filler settling, that's one of my pet hates, too!

[islandman]

didn't get much done today, finished the flange but still need to touch up the candle wax in a couple of places as I decided to move the flange over where it was too close to the side window vents (just trying to save myself some awkward sanding of the flashing lines later). I'm travelling tomorrow for the next couple of days so it won't be until the weekend I suspect when I start on the PVA

[Dirk]

Nice tip on the candle wax, I'm just finishing a plug for my head light louvres so I will give it a try rather than clay.
To PVA or not to PVA its a question I am asking myself, do you think you need it? its good if you are doing something with FG and just want to pull it off a mould, like your air vents, but making a mould from a plug it wont have such a good finish using PVA?

Dirk

[islandman]

Nice tip on the candle wax, I'm just finishing a plug for my head light louvres so I will give it a try rather than clay.
To PVA or not to PVA its a question I am asking myself, do you think you need it? its good if you are doing something with FG and just want to pull it off a mould, like your air vents, but making a mould from a plug it wont have such a good finish using PVA?

Dirk

Good question, I'm just going by advice given to me by others and the process I followed on my first mold. However I do see your point though as the PVA itself will change the finish. In the case of my first mold it probably improved the finish as it reduced the truck bed liner finish coarseness

[islandman]

One opinion I have had back is that if the part is painted there is a high chance that the paint may end up sticking to the mold. I may err on the side of caution and use PVA, mainly as I know my plan is to cover the dash in Alcantara cloth to reduce screen reflection at some point so the final finish becomes less of an issue. Having said that I am treating this part of the project as a learning process and it would be nice to get as good a finish as possible seeing as I went to the trouble of having the buck painted.

[Dirk]

I guess erring on the side of caution is the better option especially if it is going to be covered anyway.

Dirk

[islandman]

I found some time eventually to do some more on my mold, I did screw up the big top section though, I left the PVA on a long time (about 3 weeks) before doing the gel coat as I had to deal with my wife and the accident. It was only when I was applying the last of the gel coat to the depression for the wiper motor I realized that the PVA had shrunk and pulled away from the part in the corners. As I had painted on 95% of the Gel coat at that stage and it was going to set soon I just had to make do and puncture the PVA skin and try to cut the piece out that pulled away and put as much gel coat as I could in the area. I know when the mold is pulled I will have some filling to do in that area. Another issue I noticed as laying the fiberglass down was that the paint shop must have done some sanding on the back edge of the wiper depression also as it was slightly undercut (it wasn’t previously). So all in all I’m going to have fun trying to pull the mold off the part, I hope I just don’t destroy it in the process!





The back and sides went OK, but then they are largely flat sections. The other area I struggled with was the front as it was full of right angles and narrow sections, so trying to get the fiberglass to conform and not lift creating air bubbles which was a real challenge. Its very far from my best work, and I found that leaving long periods of time between each section means I got out of practice as well as forgetting to apply the various lessons I had learnt, like not trying to do too much in one go.











So I will have to wait a couple of days then start pulling the mold and see what state it is in, or if it will pull at all.

[Buffy]

I am just glad you found some time between bed pan duties !!!
It's definite therapy for you I know .

[Dirk]

The back and sides went OK, but then they are largely flat sections. The other area I struggled with was the front as it was full of right angles and narrow sections, so trying to get the fiberglass to conform and not lift creating air bubbles which was a real challenge.

.

Glad you are managing to find some time to get some work done and I hope the wife's recovery is going well. Talking of air bubbles I manged to finish getting the paint and filler of mine at the weekend and broke through the gel coat in lots of places where there were air holes in the fibreglass mainly on the edges of corners but when I had finished I jet washed the whole body and that broke through the gel coat in lots of places leaving even more pin holes.

Dirk