Originally Posted by guitarcher

One skin surface has been rubbed back with wet and dry starting at 320 grit, then 400, 600, 800, 1200, 1500, 2000 and 3000, ....whew!!! Then the polisher was used to buff out the 3000 scratches.

Well that explains it all! You weren't joking with the million hours of sanding. The results are stunning.

Let me check my shop here.........wheres that 3000 grit sandpaper?....and the power buffer? Looks like I should spends some time down at body and fender man's shop to pick up a few pointers.


Maybe a bent mylar sheet could serve as a parting board at the curvy winglet.

Originally Posted by Knoll53

Well that explains it all! You weren't joking with the million hours of sanding. The results are stunning.

Let me check my shop here.........wheres that 3000 grit sandpaper?....and the power buffer? Looks like I should spends some time down at body and fender man's shop to pick up a few pointers.


Maybe a bent mylar sheet could serve as a parting board at the curvy winglet.

The painting and prepping of the plugs is a whole new set of skills to learn and a very time consuming part of the molding process. I like the idea of using mylar for the curved parting plane. That may work well.

Originally Posted by timbuck

Subbed I was wondering when the thread was going to start after getting txt of shinny bits and pieces

I'll put my name down for the DS spec version , cactus starts in April so hurry up and " get R done "

Originally Posted by dvdmarty1

Great looking project mate. Put me down for a light version, with ballist tube. Very lucky getting help from some awesome builders.
Still need to get my hands on one of Tims light gizo's. Should be an awesome year of gliding.

Thanks Tim and Marty, I'll put you on the list. I'd love to get out to Cactus again. The adrenaline rush of DSing has to be experienced to be believed.

The wing parting planes are now completed but with mid summer temps reaching 38 degress early in the day in my workshop I need to be very mindful of exotherming

Please be mindful of the temperature at which the foam in your wing masters will out-gas. The exotherm temperature of the resin will exceed it.... Perhaps build up the mould from multiple thin layers? Cover each layer in peel ply so successive layers adhere properly.
Best of luck

Originally Posted by Shedofdread

Please be mindful of the temperature at which the foam in your wing masters will out-gas. The exotherm temperature of the resin will exceed it.... Perhaps build up the mould from multiple thin layers? Cover each layer in peel ply so successive layers adhere properly.
Best of luck

Thanks for the advice. That was what I had planned to do. I was thinking of using a couple layers of 3mm thick MDF as core filler to reduce the amount of glass and resin required ( thus less exotherm ) as well.

His mold building ideas may help you out.

U2 stab mold part 1 (16 min 29 sec)

The wing plugs have tacked into the parting plane and the tiny gaps have been sealed with surfboard wax, coz that's what I had and it seemed to work well. The resin troughs have been fitted and then all was coated with semi permanent release aid. Today's temps are predicted to peak at 30 degrees so I intend to apply 2 layers of home made tooling coat followed by one layer of layer of glass then peelply and leave for 24 hours to cure. Glass and MDF core fillers will be added tomorrow.

Looks good. Could you take pics of your MDF fillers process please.
Always keen to learn new ways, especially if it avoids wetting out up 30 layers of cloth.

Al

Originally Posted by _AL_

Looks good. Could you take pics of your MDF fillers process please.
Always keen to learn new ways, especially if it avoids wetting out up 30 layers of cloth.

Al

Yeah sure can Al. Bare in mind that this is my own idea/plan so consider it an experiment at this stage. I discussed my plan with Tim yesterday and thrashed out the finer points of the process and I think it has every chance of success.

Tim was also kind enough to enlighten me to the fact that the humidity levels were too high yesterday and for the next few days for laying up epoxy so mold making will be delayed .

This change of plans gave me the opportunity to make a few more mock ups of the curved winglet parting plane. It took a few attempts and a lot of head scratching but improvements were made to each one until it all came together really well in the end. The second one will be a breeze to make.

Finally checked out the thread you spoke about the other day and very impressive. Will watch with interest.

The parting board at the curve winglet is just brilliant. Very clean.

Humidity is still around 100 here so molding is still delayed. The fuz has now been fabricated and was soaked with epoxy and vac bagged. More sanding and a layer of glass later today.

Originally Posted by Knoll53

The parting board at the curve winglet is just brilliant. Very clean.

Thanks Kent, they turned out as good as I could have hoped for.

Humidity levels dropped a little yesterday so I was finally able to start molding. I recently bought some gelcoat additive powder that is advertised as DIY tooling gel so I gave that a try. The first coat was hard to get even especially in the corners. When I started brushing on the second coat I couldn't see where it was being applied so I added graphite powder to the mix and this made it much creamier. It was easy to see where it was being applied to the job and brushed on much smoother than the first coat. I ran out of time before applying a layer of glass so the still tacky surface was brushed with cotton flox to provide a good bonding surface for the next layers.

Need to wait now to see what today's humidity levels are.

The first layer of 3mm MDF has been vac bagged onto the mold with a layer of 300gsm glass over. At this stage I'm thinking I will add a second MDF and glass layer and that should hopefully be thick enough.

Very interesting so for. Not worried about any print through from the edges of the MDF?

Originally Posted by Owen Hedger

Very interesting so for. Not worried about any print through from the edges of the MDF?

Well that might be an issue, I hadn't given that much thought. I'll put more glass layers on before the MDF when I do the other sides.