Build Log Sapac L39 test flight and build pictures

[MFALLON]

Originally Posted by bdelapen

You can fill the tank whether the actuator vale is open or closed, it doesn't matter. The fill valve (the one with the brass air hose fitting) should be connected to a T fitting that has the tank on one side and the actuator valve on the other. This way the air has a direct path into the tank from the fill valve.

The position of the actuator valve when filling the air tank only determines whether the retracts are going to stay down or pop up when the pressure builds.

Check out the diagram on page 4 of the attached manual.

Birger how is the build going Pablo will be at the warehouse around 8:am or so

MF

[Kevin Murray]

Originally Posted by D.B. Hooper

I have a question on the Sapac retracts.
I'm guessing the valve should be open to fill the tank? Next dumb question, which way is open? When valve is open gear goes up or down?

Just waiting for the weather to clear and get gear working. I'll get video.

D.B

When the valve is open the gear spring down, and the tank is colsed off.

[D.B. Hooper]

Originally Posted by Kevin Murray

When the valve is open the gear spring down, and the tank is colsed off.

Thanks for that info. This is my first air retract system.

More Photo's
I moved all the electronics under the wing to have more room to adjust the CG. Before I moved receiver under wing the 4200mAh was all the way back to the wall at 72mm CG.

[giddyuperic]

Hey guys I got the fill chuck today from the LHS it is from robart. How do I hook it up to my little compresser? What did you guys do or use. The hand pump is 40 bucks and the little compres is only ten bucks so I just got the fill chuck. I see lots of people using them but never asked what or how they hooked them up.

[lashmett75]

Originally Posted by giddyuperic

Hey guys I got the fill chuck today from the LHS it is from robart. How do I hook it up to my little compresser? What did you guys do or use. The hand pump is 40 bucks and the little compres is only ten bucks so I just got the fill chuck. I see lots of people using them but never asked what or how they hooked them up.

Use a ball needle on the pump side. Plug that into some airline tube on one end and the chuck on the other. Walla there you go.

James

[therealhiphop]

I finally got started on mine this weekend. One problem I ran into is that the markings on the aileron and flap covers for the mounting screws do not quite match up to the holes on the wing. I had to do some guessing in order to get them somwhat lined-up.

The instructions do mention to remember that the wing is upside down when looking at the markings on the covers, but they still don't clarify what that means. I just figured they markings are relevant to the wing being right-side up, so when the wing is upside down, the right is left and vise versa. Hmmmm, now that I type it out I can see why they didn't bother to put all that in there. One could end up more confused...

Anyway, will post pictures of my progress later.

OH BTW, that balsa sheeting on the wings is REALLY thin, so go very lightly when cutting out the wheel wells.

[Mark Huffman]

Just listed a set of NIB Sapac retracts if anyone is interested.

[MFALLON]

Originally Posted by therealhiphop

I finally got started on mine this weekend. One problem I ran into is that the markings on the aileron and flap covers for the mounting screws do not quite match up to the holes on the wing. I had to do some guessing in order to get them somwhat lined-up.

The instructions do mention to remember that the wing is upside down when looking at the markings on the covers, but they still don't clarify what that means. I just figured they markings are relevant to the wing being right-side up, so when the wing is upside down, the right is left and vise versa. Hmmmm, now that I type it out I can see why they didn't bother to put all that in there. One could end up more confused...

Anyway, will post pictures of my progress later.

OH BTW, that balsa sheeting on the wings is REALLY thin, so go very lightly when cutting out the wheel wells.

The covers have the L and R but that is referring to the true left and right of the wing.

This means if you have the wing upside down and the trailing edge of the wing is facing you or the closes to you on your bench the left side of the wing is on your right side.

Hope this will help the covers will match this way and so will the holes

MF

[D.B. Hooper]

Bench test.

sapac L-39 001TEST 1.MOD (0 min 46 sec)

sapac L-39 004.MOD (1 min 2 sec)