ORLIC

[Andyfaz]

Dear All,
First of all, thank you to everybody, this thread has been very helpful to complete my Orlik.
At present I am ready to apply a layer of fiberglass to the fuselage but I am very worried to add extra weight. I would appreciate a suggestion about the weight of the glass: 25g or 50g.
Any other suggestion would be very appreciated.
Regards
Andrea
Rome-Italy

[Geoff Pearce]

Dear All,
First of all, thank you to everybody, this thread has been very helpful to complete my Orlik.
At present I am ready to apply a layer of fiberglass to the fuselage but I am very worried to add extra weight. I would appreciate a suggestion about the weight of the glass: 25g or 50g.
Any other suggestion would be very appreciated.
Regards
Andrea
Rome-Italy

Hi Andrea,
I've used .48g on my fuselage, Is yours 1/3rd scale? Because I have a 1/3rd k8 which is very heavy for its size, but it will fly in anything , especially light winds.
Best of luck

[MarkDev]

Although I helped Geoff with some technique he decided on the cloth weight and type. I would have used a looser weave on the fuse and save the tighter weave for the wings, a heavier cloth around the wheel and maybe in the area just forward of it, just to protect the windsocks you understand?

[terry white]

Hi Andrea,

Although it is true that the heavier cloth will use more epoxy in its wetting out,It is also true that many modellers use far too much resin in the lay-up with the excess not taken off before its left to cure. After the glass has been whetted out showing the glass to have a transparent look any further resin will just add weight and do nothing else.

.25-.5 as required should be good I would have thought as''stress strength' is not required here.

As Mark has already said a little extra glass can be added where you would expect dings and hanger rash to occur .

Give the timber a quick coat of sanding sealer and let dry before you start This material air drys leaving a light coat of resin to the timber, sealing it against soaking up too much of the heavier epoxy resin coat. Also any migrating epoxy resin soaking into the timber leaves the glass looking dry and your instinct is to put on even more resin on to fill the weave.

only mix sufficient at one time to use easily in 10 mins. This will ensure that it will be still thin enough to soak into the glass weave and still be spreadable.The trick here is to have everything ready with the glass cut to size etc and work fast.

Finally take off any excess resin by carefully rolling a roll of kitchen towel over the whole of the work to soak up the excess,discarding the outer layer of toweling as it becomes soaked in resin.
The final finish should look slightly mat without shine .
Remember after the main coat has dried you can always touch up later if need be.

A final tip is that after an hour or so playing with first the epoxy ;then the hardener; then the mixing; It is more then possible to forget which container is mixed and which isn't ( many a wing has been spoilt by a model maker thinking the hardener had been added when it hadn't. So I add a little food coloring into the harder before I start. Not much a little goes a long way so be frugal with it. Now any pot that is not colored is unmixed resin and the pot that is brightly colored is unmixed hardener .But as daddy bear said the pot that has just a trace of colour is just right.
Hope this helps Terry.

[john greenfield]

Geoff's Orlik fuselage is covered in thin ply so there is no soaking up of the resin as there would be with balsa. Terry suggestions above are correct for a balsa sheeted fuselage but ply required a slightly different technique. As the ply is not really porous, an excess of resin will pool on the surface and then the cloth will float on the resin. When this is sanded back the cloth will be cut through just leaving the resin on the surface so providing no strength.
The Orlik does not need any additional strength (or weight) to the fuselage so I recommend 25g cloth just to give something to put a finish on. I apply the cloth with Falcon models Skin-crylic as it seems to draw the cloth down onto the ply better than resin or G4. Once dry I give a couple of coats of G4 and it is ready for primer.

AEB
1/2 scale Orlik designer

[MarkDev]

Geoff has finished glassing the fuse and taken the peel ply off, I suggested a 'sand coat' of epoxy and easy sand additive in places to help define the final shape and fair the lines.

M

[Geoff Pearce]

Just finished rubbing down the canopy plug, and set up a dry run of inner wing.
It all fits, got to plane down spars , then glueing together.
It feels very strong already
It's getting messy again

[Simon WS]

I can't help feeling you need a bit more space Geoff!

Simon

[john greenfield]

Geoff has finished glassing the fuse and taken the peel ply off, I suggested a 'sand coat' of epoxy and easy sand additive in places to help define the final shape and fair the lines.

M

Mark / Geoff

The Orlik did not have faired in joins between the ply sheeting on the fuz. It has pronounced "flats" at each panel location especially around the nose area. To keep it scale you need to replicate this and not "fair" it in.
Do a google search for Orlik and look at the pictures of the full size !!?

AEB

[MarkDev]

Thats less work for Geoff then! Just as a matter of interest John, what thickness (was ply used in 1939?)was the original Orlic covering?