sounds great , looking forward too seeing it out of the mould

So, no more work for today, but now i only have to glue the plywood wing profile and final tune the fillets. Then in the week i hope to spray the final coat before moulding... I couldn´t recist to fit the cowling nicely to fus, some putty and sanding but i like to get things integrated...

Originally Posted by Rikard Levenstam

So, no more work for today, but now i only have to glue the plywood wing profile and final tune the fillets. Then in the week i hope to spray the final coat before moulding... I couldn´t recist to fit the cowling nicely to fus, some putty and sanding but i like to get things integrated...

Its looking nice, the carbon is going to look great when you pull it from the mould

I have a question for you experiensed large model flyer :-) What about dihedral of wing and stab? My thought has been that e straight centerline is what we need for this type of machines, but after a look at F3A models i´m not sure... How is it made on machines out there?

Best regards

Rikard

Hi Rikard
Choosing a straight dihedral center line is a good idea and helps neutralize the wing in any orientation. You will find most if not all Edge 540, Yak's and some makes of Extras have this feature which reduces any undesirable pitch or roll tendencies in flight. I've noticed more manufacturers are going this way during their design stage instead of the flat upper surface of the wing with dihedral on the bottom.

Pete

Rikard,

Have you made any cf louvers yet with the new mold?

Originally Posted by Rikard Levenstam

I have a question for you experiensed large model flyer :-) What about dihedral of wing and stab? My thought has been that e straight centerline is what we need for this type of machines, but after a look at F3A models i´m not sure... How is it made on machines out there?

Best regards

Rikard

Hi Rikard
I have tried 0 degrees and flat on the top surface (about 2 degrees) and also half way in between. The dihedral of course effects the roll couple with application of rudder (as does vertical wing placement). Actually the effect is quite minimal and I didnt notice much difference between the 3 dihedrals on my models. It really comes down to how you want it to look. I now always use halfway in between as the roll couple is unnoticeable and the wing doesnt look droopy.

Thanks Rod, i have some month´s before wingspar is ready, but i think i go for straight centerline, just as my small sukhoi, sounds okey if you tried different.

Fuselage master painted and slightly sanded and will be placed for moulding tomorrow! I ordered some extra kg epoxy sp i don´t runout och hardware..

I machined yhe inner mould for the louvre and will mould the firstone this week if nothing happends out of my comntroll at work.

No pictures before fus lay up.. nothing exiting just dust and emty spray cans....

/Rikard

Here we gooo... Gelcoat in place, the first mould out of three for fuse... 2hr before i can ad first layer of glasfibre.

/R

First side roughly trimmed and turned around. Hopefully i have a day off from work this week do mould second side (Of three).

Mould is around 5mm thick.

/R

This is a beutiful view, mould came loose very easy and screwed together to cure some more dayd before sanding and polishing.

I also started to build a new vacuum pump/tank with a vacuum switch bought on ebay. I am so boored of refridgerator pumps working and getting to hot..

Have to order carbon for fuse, think 40g/m2 Gfk+200g/m2 Cfk+163g/m2 glas on inside
Have to do some test panels..

The small Sukhoi is build by 40g/m2 Gfk+160g/m2Cfk+100g/m2Gfk

/Rikard

Hi Rikard
I highly recommend a glass foam glass fuselage laminate. We only use carbon for high stress points like the firewall, undercarriage, wing mounts, and around the canopy cutout. Cover the fuselage with as much 2mm divinicell foam as possible. We spray white epoxy undercoat into the mold first then 2 layers of 80 gm glass/foam/1 layer of 80 gm glass. This is what we consider a heavy and safe layup and is incredibly stiff and still pretty light. The limiting factor for reducing the weight of cloth is that a light cloth outer surface is susceptible to handling pressure dents. I think the best layup would be something like 80gm kevlar/2mm divinicell/50gm glass with local carbon reinforcement as required.

Mold is looking great.

Can you show us detail of the compressor to vac pump conversion? This is always an issue getting a good reliable pump.

Hi Rod, thank you for the info. I have to consider using foam in fuse.

If using Rohacell 51kg/m2 in means 100g/m2 for 2mm rohacell. + 80x3 = 340g/m2 + extra weight for glueing (?) foam.

Carbon fibre fuse is 400g/m2 laminate, Have you tried to mould a full carbon fuse? My smaller sukhoi is realy stiff and compairiable to foam fuse, but much stronger.

Vacuum pressure info is best found here http://www.veneersupplies.com/catego..._Press__Parts/
You can here buy what you need for nice price. I will post pic for vacuum when i recieve my parts.

/Rikard

Were do you find divinycell 2mm thickness? What is the weight of divinycell? I use my Rohacell because i still have some Rohacell since we had a small company building airplanes (F5B and sailplanes). Rohacell is expensive and quite stiff to get folowing leadingedge if 2mm.

What else du you use for sandwich core? Honeycomb?

/Rikard

That's awesome! Hope it flies great too.