|
Post by jirvin4505 on Jul 30, 2008 20:38:26 GMT 10
.. Yes followed several(jarts etc and Steve W is helping from rc groups), ...... The first attempt at the PVA was ok, but cos the mould wasn't so good I'm having another go, and now I've got runs in the pva so will probably have to take it off(Any Bright Ideas) >Jarts ... certainly lots of great info in those Jart threads. I'm trying to talk Paul from Bald Nob into finishing his Jart plug so I can make a mold - just to be a part of the brotherhood >runny PVA - are you brushing or spraying? Removal peel it of and wipe with a damp cloth. Must have went through the apply pva (beads) remove pva process a dozen times when I kept buying wax with silicones in it (didn't know any better and the advice I was getting was ) cheers jeff
|
|
|
Post by jirvin4505 on Jul 30, 2008 20:46:36 GMT 10
Few other ideas.....
I noticed the worms you mentioned iin the thin gel coat. This is due to the gel coat not catlysing correctly and then being attacked by the following layer of resin - just like brake fluid on paint!
With polyester gel coat I tend to over catalyse and work fast 2.5% or more - mix a small batch of gel coat and test it on a smooth surface by applying some resin over the top once it has kicked. This will give you feedback on working times and stability during layup.
Filling the sharp bits with car bog. This is a useful method - most car bog is talc and resin so you can make your own to a desired consistency. I remember I use to wet out long tows of glass rovings and lay into the sharp edge at the parting board - this would give a more durable edge.
cheers Jeff
|
|
|
Post by jirvin4505 on Jul 30, 2008 20:52:46 GMT 10
With the closed pod shape any thoughts on how you are going to join the fuz when you lay it up? Is there going to be a hatch area you can gain internal access through? BTW .. I would be comfortable laying up a fuz in the mold shown in the photos - little repair work on the worms and wiggles with bog and away you go. Me I am usually in such a rush I just plasticine over the voids and push on - a bit of filler and a coat of paint will fix most discrepencies on the final fuz cheers jeff ...just planning ahead
|
|
|
Post by sf2 on Jul 31, 2008 16:36:49 GMT 10
Thats all ood info, and stuff other threads don't mention. >Jarts ... certainly lots of great info in those Jart threads. I'm trying to talk Paul from Bald Nob into finishing his Jart plug so I can make a mold - just to be a part of the brotherhood part of the reason to do all this , is the jart, got plans in the computer waiting till I know how. >runny PVA - are you brushing or spraying? Removal peel it of and wipe with a damp cloth I'm "wiping " the pva on with a sponge that has a smooth cloth side, tried spraying but couldn't get a thin enough consistency in the tube, as wasn't sure when to much water was to much.Did try brusing but ended up with run's, any way It's all set up nicely now to do the gel coat again. With polyester gel coat I tend to over catalyse and work fast 2.5% or more - mix a small batch of gel coat and test it on a smooth surface by applying some resin over the top once it has kicked. This will give you feedback on working times and stability during layup.
I had a faily fast set the first time and din't get good cover, probably just didn't work fast enough, that was at 1.5%, but then as soon as I thought it was dry, about 2hours later I did the resin and cloth, think I should have waited longer ??
|
|
|
Post by sf2 on Aug 3, 2008 16:29:34 GMT 10
So here are the final pics of the first half of the mould.Then you do it all again on the other side. Still having a few probs with the gel coat but this time at least it was only one small spot. I think next time I will put two layers of gel coat on, to make sure it is well sealed, cos any thin coating of gel always wrinkles when you put the resin on even after a day or two. Of course I have to cut an opening to join the two halves together, one will be where the canopy will be and the other at the rear where the V tail will finally attach. On doing a bit of searching, to get a perfect fit for the canopy, just mould a bit on the plug ,a bit wider than the area you cut out in the mould for joining access, and then make a canopy from that small mould.Sand to shape and figure out how to attach. Also if you want it to sit in a small groove or somthing similar, apparently you make a positive edge around the canopy position on the inside of the mould, tape plastacine or some such similar. That's it for now, more pics when the mould turns out a fuse. Cheers SF2 aka DH
|
|