jimibar

I'll try to take some pictures so you can understand. the tube is not held by screws but the wood piece is glued in place ...

jimibar

Hello Guys,

I have received my CMJets tank and it does not fit my F18, I have to remove some material on the fuse seperation if I want to fit it.
Before going this route, maybe I can try to repair the old tank.
The joint between the 2 shells is broken, I'm attaching a picture of it.
What kind of glue can I use ? Can I use standard epoxy ?
Thanks !

rhklenke

My Feedback: (24)

It is absolutely possible to fix that crack. You have to *thoroughly* clean the fuel out of the joint, then I would Aeropoxy it back together and then glass over it with an additional layer of glass, going beyond the area of the crack.

Bob

jimibar

Thanks Bob,
I already applied epoxy all other the crack and on all the joint.
I will apply some layer of glass tomorrow.
Thanks for your reply

ravill

My Feedback: (11)

Aeropoxy is not regular epoxy. Google Hysol 9462. That is the stuff you want.

jimibar

I know that aeropoxy is not the same as epoxy but I had an answer from a friend before I was reading the reply from Bob, so I used regular epoxy. The tank has been already repaired by the previous owner, that makes no doubt ... And he used epoxy unless I'm wrong.
I'll try to reinforce the joint and I'll make a filling test - without forgetting the pressure cap (...) this time - and see if I have any leaks.

Now it is time to make a turbine choice. Plane without engine and dry is 11kg or 24.2 lbs, with the stock tanks I think it will be around 15kg (33 lbs), but still without engine. What kind of turbine would you recommend ? I want to try a Kingtech but do I stay at a lower ratio with a K160 or go bigger with a K180 ?
Thanks.

ravill

My Feedback: (11)

A K160 will be plenty for that jet.

jimibar

Hey guys,

Time to move to setup the plane.
According to the manual found here : Skymaster ARF F
CG is at 140-160mm from the leading edge ?
Ailerons between 12-16 mm up/down
Elevator between 40-45 mm up/down
Flaps 20-25mm take off
Flaps 55-60mm for Landing

Does it looks correct or would you suggest any modifications ?
Thanks !

jimibar

Plane is ready to maiden.
I balanced the plane at 140mm which is the wing tube, so I just hang the plane by the wing tube and balanced it like this.
Any suggestions on this CG or it should be fine ?
AOA AUW is positive as explained earlier by most of the people

ravill

My Feedback: (11)

20-25 mm for flaps sounds a little too light for my tastes, but on your first take off, if it hops off, that will be a contributing factor.

jimibar

Thanks Ravill, will increase to 40mm for take off then and 50mm for landing.
What do you think about the CG at the wing spar ?

ravill

My Feedback: (11)

If I remember correctly, the CG was on the front wing spar.