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Scale 1/4 Scale 148" Shrike Commander

Patto

70cc twin V2
That's really not too bad. Considering its size. I keep thinking back to my old Lanier Extra 300 from eons ago. Heck, my buddy was the boss of the fields with his old and heavy Zenoas and the old early and massively heavy mighty dub engines. (Give you an idea how long ago that was? Lol) That was just right before I got my first ZDZ 80cc online twin. I equipped my Lanier Extra with a Moki 3.6 inline twin. Basically, a 60cc glow motor. You remember those right? By my standards now, it was not so big at 102" wing span. But heavier than a 747-400. 36 pounds at take off. It is crazy to think that we would fly a 35% airplane such as a pilot 107" Edge with a 60 cc motor. Heck, most of the 35% planes come in around 28 to 31 pounds. That said, my Lanier extra flew really well with that moki twin up front. It wasn't great vertical by no stretch of the imagination. But it flew it pretty nice. But then again, I only had 102 inches hangin' in the air. You'll have a 148 inches out stretched. Too bad the 60 twins wont fit your cowls. Or will they??
I highly doubt the 60's will fit. I think I'm going to be stuck with just enough power with the twin 40's or cut up the cowls and have an ugly cylinder hanging out the bottom with a pair of 60's. The twin 60's I'm sure would be too wide.

You're right though. Folks used to fly things like this with a pair of .90 Supertigers and lifted off with their fingers crossed while saying a prayer. I would think a pair of 40's probably produce a combined 40 lbs of thrust, which really should be enough.

I'm aiming for a 45 lb airplane...
 

Patto

70cc twin V2
Spent some time today placing stringers, measuring, placing, measuring, gluing, etc.

The issues with the notches not lining up correctly have been covered well in another build thread, and I can confirm there are several places where things don't line up quite right. The main problem is with FF-5. It just doesn't work well with others!

I'm still waiting on the rest of the plans to arrive. They got here with only the bottom halves of three of the sheets. They are so large that they come in two sheets for each original.
 

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49dimes

Damn I'm hungry
I highly doubt the 60's will fit. I think I'm going to be stuck with just enough power with the twin 40's or cut up the cowls and have an ugly cylinder hanging out the bottom with a pair of 60's. The twin 60's I'm sure would be too wide.

You're right though. Folks used to fly things like this with a pair of .90 Supertigers and lifted off with their fingers crossed while saying a prayer. I would think a pair of 40's probably produce a combined 40 lbs of thrust, which really should be enough.

I'm aiming for a 45 lb airplane...

With a 20x10 or 21x8 prop a well tuned 40 twin should get you 24 pounds of thrust. X2= 48 pounds total. If you hit your goal weight of 45 pounds those twin 40's should be quite sassy!
 

Patto

70cc twin V2
With a 20x10 or 21x8 prop a well tuned 40 twin should get you 24 pounds of thrust. X2= 48 pounds total. If you hit your goal weight of 45 pounds those twin 40's should be quite sassy!

Looking around, it appears the best options for twins are the VVRC 40's, RCGF 40's, and DLE 40's. Another option would be EME 35's with autostarts, assuming they would fit. I don't know what the power difference would be.
 

pawnshopmike

Staff member
Looking around, it appears the best options for twins are the VVRC 40's, RCGF 40's, and DLE 40's. Another option would be EME 35's with autostarts, assuming they would fit. I don't know what the power difference would be.

I had a DLE 40 on a Stinson. I bought the DLE brand new and I put Bowman rings in it before the first start. I also replaced the plugs with NGK's. It was hard to start and tune but it had awesome power. So the next thing I did was put a real Walbro carb on it. Once I did that, it was a great engine. Easy to start and tune. Transition was great and way more enough power for the Stinson.
 

49dimes

Damn I'm hungry
Looking around, it appears the best options for twins are the VVRC 40's, RCGF 40's, and DLE 40's. Another option would be EME 35's with autostarts, assuming they would fit. I don't know what the power difference would be.

EME 35 about 21 pounds static thrust with 20x10. But I totally forgot about the RCGF 50T! Angled plugs and only 8.77" inches across plug caps. I personally been wanting one. A bit pricy @420.00 though. But it will produce almost 30 pounds of static thrust with a 20x10 !
I had the single cylinder counterpart the 26cc....same size as a DLE 20 but would put the smack down on it! The 50 is the same size as the DLE 40 and yes the 50 puts the smack down on it too!

50cc-T_23.jpg
 

Patto

70cc twin V2
EME 35 about 21 pounds static thrust with 20x10. But I totally forgot about the RCGF 50T! Angled plugs and only 8.77" inches across plug caps. I personally been wanting one. A bit pricy @420.00 though. But it will produce almost 30 pounds of static thrust with a 20x10 !
I had the single cylinder counterpart the 26cc....same size as a DLE 20 but would put the smack down on it! The 50 is the same size as the DLE 40 and yes the 50 puts the smack down on it too!

View attachment 106157
I think those would actually fit, although I have yet to personally meet an RCGF engine that runs well. Any chance you feel like testing one out for me? ;)
 

Patto

70cc twin V2
I decided to cut the remaining formers into halves and build 1/2 first on the board, then build the other side onto it. I will then attach that to the remainder of the fuselage. At this point, I plan to make it all one piece without the need to put them together at the field. This is going to result in a fuselage that is looking like it will be about 9 feet in length.

Unfortunately, the formers are just not lining up right at all. Some are too short and some are too tall for where they sit on the plans.

I think the only solution is to find where they sit best as far as their height so that they don't throw off the lines of the fuselage.

Ugh.

I still don't have the complete plans from where I ordered them. I was only ships the bottom halves of some of the sheets, including the fuselage ones. So I have no way of checking the former's to see if it is an error on the side view or if the parts were cut incorrectly.
 

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49dimes

Damn I'm hungry
I think those would actually fit, although I have yet to personally meet an RCGF engine that runs well. Any chance you feel like testing one out for me? ;)

Lets just say I tested half of the 50 lol. The RCGF-26. It ran VERY strong. Ran VERY well. Yes it was hard to start for the first time of the day (Needed a starter) but starts after that came easy by hand. The smaller crank cases makes getting the carb primed a bit difficult on these class of motors. Had similar issues with DLE 20 etc...
And RCGF is up front about this in their manuals. "First prime of carb will take 40 or more turns of propeller". The only other thing about the RCGF is the plug cap on their ignitions. I measured and found it to be a wee bit larger than the RcExel's. Fix is to add a small hose clamp to keep it from making RFI on the plug. But be as things are.....Send them to me and I'd be happy to test them for you :).
 

Patto

70cc twin V2
After doing a bunch of studying the plans and trying to match pieces up, I have concluded that the former's will not work. They simply are not cut correctly. I checked the stabilizer ribs and found that they are not cut correctly and several are missing. The wing ribs appear to be usable although not perfect.

At this point, I am going to have to start all over again it looks like. I may be able to salvage a few of the fuselage formers but I'm not sure. After measuring them and comparing the heights they should be on the plans, I am finding that they are not matching up correctly.

I'm pretty bummed but not enough to quit. Getting ready to place a good sized order with Balsa USA.
 
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