Manish Chandrayan

Are you modelling one with floats?

1:20 is the ratio of lube to fuel. 1 L of lube in 20 L of Fuel is right. That 1:20 implies one portion of oil for 20 portion of oil The portion could be anything as long as both oil and fuel are measured using the same portion. Lot of folks confuse this.

It's on OZ

Update on the issue I had sought advice. Last weekend, ran the engine some more. The leak did not seem to get any worse. Once the engine had cooled down, cleaned the area as best it could be with cellulose thinners and then alcohol and allowed to dry. Some CA was applied carefully to the area and again allowed some time to dry. The area was then capped with some JB weld and model wheeled back to storage at the field that we are fortunate enough to enjoy. This weekend wheeled the model out, installed batteries etc and inspected the leaky area on the engine. The JB weld had nicely cured. Fuelled up and started the engine and ran about half tank in the same rich condition it was. No leak was seen during the run. Allowed to cool and then the engine was run again this time tweaked the needles a bit to lean off the engine. Took it to 6800/6900 on onboard tacho with a 23x8 falcon and still being on the richer side. Satisfied that there still was no leak, put on the cowl and had two flights. The engine tune changed with the cowl on, so will tweak that next time I fly the model. Will also take a look at the engine area to see if there is any leak. In summary the fix seems to work.

Instead of decal, a stamped metal plate would be a pukka job

The iMax B6 and similar perfectly charge single cell glow boosters. I have been using that for quite some time now. If your battery chemistry and count selection is set correctly to NiMh/NiCd it should charge the glow driver. Few things you could check. Is the cell in the driver serviceable? What charge rate are you trying to start the charge? If trying at low rate, try bumping it to 1/2 Amp and see if starts the process. If it does, terminate the process in say 30.40 seconds and try at a lower rate Is the charge lead fine? not shorts etc.?

To Cuban8's point, and especially when it came to 2 strokes, the piston and cylinders from ASP were much better than OS for the OS 46 FX. When these were available Just Engines used to retail the ASP piston liners as replacement for the OS 46 FX. I have personally used them as replacement parts on few of my OS

Richard, aren't you going in for the "OFF" label on the switch plate?

Another issue would be to mark off the areas that do not need any paint as those will need sticking to the substrate. In my view it would be better to paint the interior (the visible parts) after the covering has been applied

Thanks for the link Bert. Loved watching 👍

Congratulation on the beautiful build and maiden👍. I can not open the video file uploaded by Bert. Anyone else facing the same issue?

Thanks for your suggestions Engine Doc. The engine was rebuilt by myself. Pictures of old and new set of parts at the end of this post. The case halves are flanged to mate and do not use a gasket. When I had disassembled the engine I did notice some kind of cured retaining compound. During assembly , I used Loctite bearing retaining compound on the flange but faintly remember not applying any around the index pin. Was apprehensive of the pin getting glued in and causing issues if and when the engine needed disassembly in future. The engine was being run rich as this was the first tank of 25 oz fuel. I do understand the importance of case sealing. Will lean out and see what the engine does I was thinking, what if I clean the area as best as possible, and dribble a drop or two or cyano so that it wicks in and then cap the area with some epoxy/JB weld. Not the best way to handle the situation but that would preclude opening up the engine and loosing the cylinder piston ring fits that have started to fit and bed in.

With all new internal parts the NGH 70 was assembled and run. During running I noticed a tiny leak from the index pin area of the case join (marked with red arrow). There are no other leaks and the engine while running rich (1 3/4 open on both needles) is doing 1600/1700 idle and 6400/6500 with a 23x8 Falcon prop. What is the best way to stop the leak of raw fuel from the area marked? I would prefer not to disassemble the engine. Or should I just leave it alone. The worry being raw petrol being expelled and once cowled can that pose a risk?

Jeff If the bendy pipe is touching the ply it will eventually start singeing the wood. A fiberglass bandage around that part should prevent it. I also hope that you will install support for the pipe and the muffler

Mark Most quarter scale Tiger Moths get flown powered by engines between 120-180 size. So if you choose an engine in the middle of the range you should be covered. Laser/Saito/OS/Enya take your pick based on your preference. If you know your models turn out on the heavier side of the indicated weight range or if you intend adding lots of scale details etc go on towards the larger engine size. The Tiger mostly flies on wings. I was very skeptical with my quite heavy quarter scale till I flew it for the first time. The 150 does a fantastic job of flying it like a Tiger Moth. Curious why do you say the prop is 16x6? Would that not depend on finally what engine you choose and how you want your model to fly? If you want the prop to be near the scale size on your quarter scale model, the prop should be around 19" If your prop choice is fixed at 16x6 a 120 will be best suited for the given prop and the Tiger. Just keep everything as light as possible.