[Balsa Fuel Tank]

Posted by Rich Griff on 25/01/2021 15:03:13:

Hi levent, how did your bespoke fuel tank perform, any leaks ?

Iwhat was its final weight, and was it lighter than a tin tank ?

No leaks any in raw fuel. I didn't test it with a running engine yet.

Total weight is .547 ounces. It is a little lower than a tin plate fuel tank. Final metal epoxy add much weight. I think that two clear coats on inside and outside are enough.

I also want to try an epoxy model paint coat after applying a coat of epoxy glue to save weight, however I could't find epoxy paint in my country.

[Graupner Silentius Model with Vector unit]

[Graupner Silentius Model with Vector unit]

[Graupner Silentius Model with Vector unit]

[Graupner Silentius Model with Vector unit]

[Graupner Silentius Model with Vector unit]

https://www.mediafire.com/file/1p2inxkarmdhtol/A4_Silentius.png/file

Edited By Levent Suberk on 08/01/2021 07:54:19

Edited By Levent Suberk on 08/01/2021 07:55:26

Edited By Levent Suberk on 08/01/2021 07:55:55

Edited By Levent Suberk on 08/01/2021 07:56:26

Edited By Levent Suberk on 08/01/2021 07:58:13

[Graupner Silentius Model with Vector unit]

4 gram weight added to nose. Total weight is approximately 63 grams.

[Graupner Silentius Model with Vector unit]

Fuselage finished with thinned dope and thinned Vallejo Model Color acrylics.

[Balsa Fuel Tank]

Posted by Geoff S on 03/01/2021 14:12:24:

Tin plate is fairly easy to work with, I think. It's thin enough to cut with scissors. It solders easily and, at this small size, wouldn't even need a big soldering iron. However, it's worth a try and I'll be interested to see if proves to be fuel leak proof. I wonder if it will survive a heavy landing?

Geoff

Hi Geoff, it seems that there is no leak any. I will send a message after testing it with raw fuel and also with a running engine.

I think that it can survive a heavy landing, and even a crash if it is small model that uses 1/2A engines or similar size.

It look like a fibreglass tank and light.

[Balsa Fuel Tank]

Posted by Rich too on 03/01/2021 13:46:35:

Mmm, no experience, but balsa would be my last choice. Have you consider a bag?

**LINK**

Hi, I have balloon fuel tanks and they work, however I wanted to try a novelty idea.

[Balsa Fuel Tank]

Hi, I wanted to make a special shaped tank to fit inside of a profile fuselage. It can be made with tin plate, however balsa is easier to work than tin plate. I am going to use it with glow fuel 15% nitro.

[LiPo Starter Battery]

Posted by Martin Harris - Moderator on 01/01/2021 16:36:09:

My main motivation is avoiding the self discharge liability of my glow sticks.

Martin, you are right about this self discharge, a negative side of NiMh batteries.

[LiPo Starter Battery]

The power output of LiPo battery is steady throughout the discharge, but the power output of NiMH batteries starts to decrease after charging. Also amperage of NiMh battery instantly drops while using. So a LiPo battery has longer drive time and better performance for a good hot glow for glow plugs. Also LiPo batteries have an instant high current output.

Edited By Levent Suberk on 01/01/2021 16:39:53

[LiPo Starter Battery]

Posted by Phil McCavity on 01/01/2021 16:29:10:

Would a genuine Panasonic 18650 be a better and cheaper power source for this?

Edited By Phil McCavity on 01/01/2021 16:32:19

Phil, of course any battery can be used, if battery voltage is in input range of circuit.

[Graupner Silentius Model with Vector unit]

Fuselage building.

[LiPo Starter Battery]

Good news Martin

[Balsa Fuel Tank]

I cut parts from 2 mm sheet balsa. Fuel tank capacity is 25 cc / .85 oz. Size is 50 mm x 50 mm x 10 mm inside and 54 mm x 54 mm x 14 mm outside. I couldn't find copper or aluminum tubing, so I used a 3 mm telescopic antenna tubing. Total weight before applying epoxy is 5.0 grams / .177 oz. I applied thinned 24 hr epoxy on parts and vacuumed. Assembled box, opened fuel tubing holes and sanded the out of box. Then applied second thinned epoxy coat to inside of box and cover. After drying I glued tubings with metal epoxy and glued cover on box. Then applied two coats epoxy on out of box, last coat is metal epoxy. I think that last coat metal epoxy is a little heavy. 24 hr or 30 min thinned epoxy must be used instead of metal epoxy. Total weight is .547 oz. I have been trying it with fuel.

[DIY Center Finding Tool]

This simple device can find the center of any round object. Glue a straight ruler on 45 degree triangle as shown. Ruler must be glued on exactly between on 90 degrees corner and center of long side of triangle. Place straight ruler on round object and draw a line. Then turn device and draw a second line. The intersecting point is the center.

[Graupner OS NSU Wankel Type I - 49 Instructions]

Instructions for Graupner OS NSU Wankel Type I - 49

https://www.mediafire.com/file/k4o58ooltfqhvi0/I-49_wankel_instruction.pdf/file

[Advent Prize Draw - 24th Dec - last one!]

Good prize.

[Magnet Clamps]

Using neodymium magnets as a clamp.

[Graupner Silentius Model with Vector unit]

Thanks Gordon.

[Graupner Silentius Model with Vector unit]

Thanks for this Kremen, it looks very good. Yes, that model reviewed in Aeromodeller magazine, but which issue I don't remember. It is very nice that you have original propeller that has been given by famous modeller Ron Moulton.

Electra Fly uses a Mabuchi motor?

Edited By Levent Suberk on 23/12/2020 14:26:56

[Cox G Size Starter Battery Reproduction]

From Cox 1974 catalogue.

[Cox G Size Starter Battery Reproduction]