3D Rebuilding the Compy MX2.

[Mikeq]

I hear ya and it all makes since...there have been several planes that have come and gone...the Cap 232 and the Laser where two I never owned but would have loved to.. I guess you can still get them as kits but not ARFs. If you see something you really like better grab it because it my not be around for long...

 

Oh boring circles don't bother me...seeing that Pitt fly and hearing the engine roar would satisfy me...

 

[stangflyer]

reyn3545 said
It's been a cold, rainy, windy weekend, so I thought I'd go ahead and get the baffles built.  I've never been a real craftsman at this, and today's creation is no exception, but it should push air in the right direction.  I think that's the name of the game.

They're all glued in place, and I've given them a wet coat of West Systems epoxy.  Once that cures, I'll probably paint them black.  

 

You really don't need that much motor in that plane. Tell ya what.... I'll get ya a more "appropriate" sized motor....like a DA 150 or sumtun like that. You send me the 157csts in exchange. We'll call it good....K? LOL

 

[stangflyer]

Besides, Orange Jugs and a green plane...just doesn't do anything for me. Now orange jugs and an orange Sukhoi...would look "AWESOME". hee hee

 

[reyn3545]

Aw, man... I wish you'd have said something earlier today.  Unfortunately, I have the baffles done now.  As you know, on a 3W, the right cylinder is forward, but on a DA, the left cylinder is forward.  If I swapped motors now, I'd have to rip out a perfectly good set of baffles, and I'm just way too lazy for that.

 

Anyway, here's the finished baffles... flat black, so hard to tell much, but they are done.  I may need to put a little more bracing under the bottom, they're a little flimsy down there, but that won't show.  

 

[stangflyer]

Dude..that looks really great. I think you did a really nice job. A little support on the bottoms will be a good idea. In all seriousness... I am still so tossed up about the motor for the Suk. I have bounced back and forth so many times I am starting to feel like the opposite sex. LOL....

Wanted the ease of installation... DLE 170, DA 150 and 170, and GP EVO 176 exactly the same mounting bolt pattern. 80x90 mm. While the 3Dub 157 and 170 are different. The firewall is already drilled and blind nuts installed to accommodate the 80x90 pattern. But I do love my 157 in my 260. Tons of grunt and just sounds bad to the bone. A bit pricey compared to the others... 2600.00 for the 170, (including exhaust) verses 1500.00 for the DLE, about 2000 for the DA 150 and 170. About 1800 for the GP. I hear so many stories from other people that have "ALL" these motors and they all swear by them and all run awesome. I just can't make up my mind. I know I have been putting the best of the "BEST" in the Suk. Oh, I know....how about a seven cylinder Moki 250???? 

 

[Bunky.F.Knuckle]

reyn3545 said
It's been a cold, rainy, windy weekend, so I thought I'd go ahead and get the baffles built.  I've never been a real craftsman at this, and today's creation is no exception, but it should push air in the right direction.  I think that's the name of the game.

They're all glued in place, and I've given them a wet coat of West Systems epoxy.  Once that cures, I'll probably paint them black.  

 

Baffles look great!!

 

[reyn3545]

One thing you have to be very careful about with radial engines in today's ARF's... the planes just aren't made for that kind of weight on the nose.  You'd wind up adding a ton of weight in the tail, then the wing loading would be so heavy, you'd end up with an expense, great sounding trainer plane.

I found a good deal on a Moki 150 a while back, and I wanted a biplane for it, but I decided to start out with a 100cc Pilot Yak.  It had a great big cowl on it, just right for the size of the Moki.  It went together very easy, but when it came time to balance, I had to add almost a pound of lead shot inside the tail tube to get it to balance.  I don't remember what it weighed, but it was the most sluggish performing plane I've ever had.  I parted it out in less than 10 flights.  

And I started my Pitts out with one of the new Evolution 250 7-cylinder radials.  The motor was a piece of crap, and it was too heavy.  With 7 cylinders, you don't get the rumble like you do with a Moki 250, and that motor leaked oil out of almost every cylinder.  I sold it CHEAP to a guy in Australia, and bought the Moki 250.  It's been a great combination.  Not a speed demon, but a very scale flying pitts.  The MX-2 will be my speed demon!

 

[reyn3545]

If you're torn between the DA170 and a 3W, let me confuse you a little more.....



I put a DA170 in my previous MX2. It has a little less torque and horsepower than the 3W 157 CS TS, but it is a VERY smooth running motor. Here's a clip I did once I installed a Vess balance ring on the propeller. Absolutely no vibration in the wings, tail or even the wheel pants at idle. DA makes a very dependable, smooth running motor, easy to tune and starts with little effort. I'm sure the 3W will be just as nice, but the 157 does shake a little more at idle than the DA in this video.

 

[Bunky.F.Knuckle]

How thick did you make your baffles, Mike?

 

[reyn3545]

I used some 1/32" birch plywood from the local hobby store.  It's very light, and when you coat it with West Systems epoxy, it soaks in to make a strong, fuel resistant surface.  A little bracing behind the vertical surfaces and the same under the bottom, and it should work just fine.