Why did you leave the ant. hanging out the back of the plane like that. Wrap it around a straw and stick it down the inside of the fuse and get it out of sight. The plane looks great though and I love the paint job.
Ed

Alca, you're getting the Pacer and Super Pacer confused. Doug, what did your final weight turn out to be? I still have not flown my rehabilitated Super Pacer, it was coming out so light I went back to the reccommended ST.23. , 42 oz all up. Now with your comments, I wonder if I should put in a .32. I have an old heli .32fsr, I put a regular drive washer on it and trimmed back the head fins.
Don

Hi Doug...I know this thread is a bit old, but I am starting to build this same kit. Can you clarify why you decided to put the fuel lines out the side of the fuse?

Thanks!

Double post.

iforbes,

If I may take license since I built one too a year ago...

The FW on the SP is pretty much filled up by the motor mount as one can see in one of the pictures of Doug's build. This leaves little room to route the lines out around the mount without weakening the tristock holding things together up front. Since the original SP had a side mounted engine as Doug did (but the box photo shows an upright install I believe), then, passing the fuel lines out the side might have just made a lot of sense to keep them short and direct to the carb and muffler.

Your post inspired me to dig up some pictures of the yet to be covered SP but here are some ideas on what I did with mine. I ended up substituting practically all the wood in the kit and also used thinner stock in a few places since I was going electric. I ended up with a 48" span (stretched the wing) SP with an AUW of 40 oz; battery, retracts and 5 servos included.

You might want to examine the wood in your kit especially the fuse sides - mine were rather unequal and the horizontal fuse top line was all over the place. This model is actually so nice and simple, it deserves a good modern short kit which actually someone here has done but unfortunately he has been rather busy with other things. In any case, the kit probably deserves some slightly fresher and lighter wood stock. Ace kits weren't exactly an ace in terms of wood quality as far as I can tell.

All that aside,... build on!

David.

P.S. My apologies for the horrible "green screen" background in the photos. Every time I see it I cringe. I'll hopefully take some nicer ones soon.

Oh,

whatever you do, I recommend you don't attempt the D-tube lightening trick I did. I was taken to task on this experiment in a serious way - understandably so. There are all sorts of ARF's that have lightened D-tube sections but they are typically square. the round holes were not liked by the aerodynamicists.

But as they say, the proof is in the pudding. I will fly it, experimentally as I mentioned, and confirm that it makes a difference on a model like this. Somehow I doubt I'll notice a difference in flight behavior other than due to its exceedingly low wing loading. But I'm excited to be proven wrong!

David.

Gents,

Maybe interesting to look back on a part of the learning curve of the experiment to make these (aerodynamic ugly) holes in the D tube.
See these thread and posts:
Post 121 the idea:Since I also found it to be much better than the usual sheet shear webs, I used it too on an another wing. I bet it's really light! http://www.rcuniverse.com/forum/fb.asp?m=9703376

Post 123 my first comment:
http://www.rcuniverse.com/forum/fb.asp?m=9703376

and read the posts until post 134
http://www.rcuniverse.com/forum/fb.asp?m=9708957

And the successful end of the curve:


I always write my posts based on facts. People arn't always happy with that, but that take time. They learn.

Cees

Hi David,

I really like what you did with your kit. I would be interested to see how it flies...esp given the controversy it seems to have stirred up!

I plan on building this as it came and to the plans (making modifications only where necessary...ie fuel tubing routing). I am still a novice builder so am reluctant to bite off more than I can chew.

Thanks for the input!

Well thanks, it really was a design that I felt I could go to task on and do a bit of anything that came to mind. I am not really very experienced with electrics and have been curious as to how a very light yet classic airframe like this would respond in flight. Building it stock makes for a nice and sold airframe though. If there is one mod that I would do, it's to make the fuse sides symmetric and equal in length. Once the nose has been closed off and sanded to contour, you can make a cutout for the engine on the side (or top). But that might be just due to my sense of aesthetics liking symmetric pattern aircraft. On the other hand, leaving the right side cut short at the FW gives it an SP design signature. Actually, later, Owen Kempen started to build them the way I describe which is more conventional I suppose. Below is a picture of an airframe he built. The fuse is already primed as you can see with the cutout. I attached a couple of other snaps of a SP I found on the net for inspiration.

If you choose to go the symmetric route on the fuse, of course make sure you get the engine and mount aligned and installed on the FW prior to gluing it in - obvious stuff I suppose but I didn't want to be offering a suggestion that would lead you to think - "well, that was positively brilliant" later on once your fuse was complete... On the note of the fuel lines, if the engine is located on the mount beams sufficiently forward from the mount body ring, you can probably pass the lines out through the center of the mount. This might make for a "cleaner" airframe.

As far as controversy goes, well, there is none left anymore now that we have all been enlightened by the Jedi. We would all be lost souls wandering in the heart of darkness searching for a beacon of R/C light. Alas, I am fortunate since I have found mine. I am now truly enlightened and have ascended apparently successfully completing the learning process - I have finished the curve!

From this point henceforth, I shall refrain from doing anything that is not conventional or in accordance with our Jedi, for he is the one master and guide and should I falter, there will be no return from the pit of despair...

Without our beacon of light, there would be no poetry and all would appear as barren landscapes and we would be overcome by desolate sorrow in our R/C ignorance.

And with that little detour, I'll return to the usual me. My apologies, it just couldn't be helped.

When I get her airborne, I'll be sure to post my impressions (I may have to obtain a top secret location first...).

Enjoy the build!

David.

David,

I am an industrial designer and engineer. A main part of my education is fluid mechanics, (liquid- and aerodynamics) and instrumentation so of course I immediately see these kind of modifications you show, the holes and shear webs, are not a result of real engineering and/or calculations. Writing about that never can be a problem, for me, it is the goal of RCUniverse, sharing know how.
BTW, same story, the fuse of the foam cutter, but that’s much more riski, because of life danger!

Cees

Cees,

I am an absolute novice at all this stuff, but it has been my general experience that what holds true in practical and full scale studies in fluid dynamics do not always translate to small scall studies. It will be interesting to see what happens in the real world when David takes it out and puts it through its paces.

iforbes, Novices can’t have a “general experience”.

No one was talking about “full scale studies in fluid dynamics”! .Parts of cubic mm’s air pro second is also fluid dynamics, see the picture (if I can it upload?).
More important, a current (electrical fluid!) of 10 milliamps is enough to blow down a life, a RCD only can protect you for 30.

Cees

Not possible to upload, so later,
The device I did want to show is a ventury, we calculae the output flow in parts of cubic mm's, for example.
several attemps! Later.
Here we are, RCUniverse, SUPER

iforbes
This a an old thread, so why not.
The ventury is of a 30 years old glider, picture 2

New to all this stuff = flying rc planes.

General experience comes from life, reading, and other hobbies, so I guess I can be a novice yet still have general experience...

I was just wondering out loud...

Your data

Airplane Experience - 1 years building
- 0 years operating
- Beginner pilot

Mine

Airplane Experience - 44 years building
- 44 years operating
- Expert pilot


Have fun.


Cees

Wow!

You are kind of a jerk.

I do plan on having fun!

Hi Cees,

I couldn't agree more.... with your last point "Have Fun!"

That is the point. It is also why we do this. Will the covering tend to "flatten" the airfoil over the holes in the leading edge D tube and change the airfoil slightly in that area? Yes. But more importantly will it change for the good or the bad? Who knows. This is why we try these grand experiments.

With over 40 years building & flying experience I have seen many things that do not always make sense. Small changes measured in fractions of an inch that dramatically altered flight charecteristics. On the other hand I have small 1/2A foam combat delta wings that are a flat wing with a small leading edge sanded in that fly wonderfully. How many times have I done full wing, tail, and fuse CG calculations downs to the last 1/64" only to find that in real life the plane likes the CG in a different spot. It's part of the grand experiment and why we love the sport. Otherwise there would be no need for test pilots. In this sport we get to be the designer, builder, and test pilot all in one and still survive the ones that didn't work out so well.

So to David and iforbes, enjoy the experiment, the mystery of flight, and above all, as Cees so aptly stated, Have Fun!

Bill

Nicely put Bill... nicely put.

David.

David, it isn’t a battle! Nobody has to win!

My experiences are, there are nearly no professionals in this forum, and for that this was important, (You write now!)
There are all sorts of ARF's that have lightened D-tube sections but they are typically square. the round holes were not liked by the aerodynamicists.

You may experience whatever you want, but sometimes I argue with you but of course with facts. Not my case if you don’t believe me!
When you should have asked me before,"Cees, you know a lot about aerodynamics, what has to be the diameter of a holes in the D- tube to make these lighter?"
I would have liked to calculate that.
And my answer? : 0 mm of course.

And, can you leave the D tube away?Make round hole? Of course you can, you can leave a complete wing away.
But I do give my opinion with my knowhow.

That foam cutter, same story.

What has to be the fuse of the mains?: My answer: 1,6 a 2 Ampere.

Can you do it with 5 Amps? Of course,

Please do not speak about R & D because you do want people believe you are an electrician and you aren’t. In this case it is much more important not to argue, simple show the facts and calculations.
Start with this post and you see I do give a normal input.
http://www.rcuniverse.com/forum/fb.asp?m=10283123

R&D? It’s a matter of live danger!
http://www.rcuniverse.com/forum/fb.asp?m=10283714

And the builder, does not even know where he is talking about, he is a modeler.
I'm not sure what went wrong with the 5A fuse choice
So, end of input in this old thread.

Be careful!!!!!


Cees

Cees your lack of respect to others is amazing and out of site.

Cees,

I'm not going to do this again with you. You have been informed many a time before by others. Change your tone and manner and everyone will welcome you. Be arrogant, condescending and assuming and you will be shunned. So called facts, engineering and calculations have nothing to do with it.

For the record I hold two degrees who's central theme are the Navier-Stokes equations. This doesn't preclude me from asking others what their opinion and thoughts are on aerodynamics. But anyone who's opinion is always based on the assumption that they are always correct and others are, if they are lucky, barely waking up to smell the coffee is just not well received. Dialogue is the key to productive communication. What you do is akin to preaching to the uninitiated - repeatedely.

If I'm lucky you wont respond to this with a myriad of references to other posts or threads.

And it is not cool to bring into this exchange (because it is not a conversation) Ralph's excellent PSU build. It has nothing to do with it.

You go ahead and be careful! I'll go and make myself some tea instead and hope not to blow up my house when I put milk in it...

Man, why is it always this way Cees? Just take a breath and put together two clear sentences with your thoughts on the subject if you deem necessary. But take a step back and realize that everything you say is not gospel. Others will be a lot more receptive. If I'm frank, you sound like an interesting person to meet but if I spoke Dutch and you came across the same way you do in English, I'd have to run hard in the opposite direction. We already have to deal with controversy and issues in our own lives. Let's not bring that here to our RCU haven - if you will.

Hopefully end of input it is.

David.

[:'(][:'(][:'(]

[quote]ORIGINAL: alcarafa


David a good psychiatrist have the answer [&:]

David, Rafa
What would have happen when I did start this in the thread of Ralph? So I did decide to combine the two facts in this thread.
It is whatever you write,
http://www.rcuniverse.com/forum/fb.asp?m=10284586

only the situation never will be clear to me,
While it is possible to buy for less money a double isolated, metal covered, fully qualified and safe power supply you writing these are for a hospital.
http://www.mpja.com/prodinfo.asp?number=9600+PS
What has an USA shop (1973!) to do to sell good and safe products in the USA? Read the description, these are designed for a workbench and how many people do not use a computerized foam cutter in their hobby shop. It is technical a clean , dry, area!!!!
Wouldn’t it be better to promote the selling of these products instead of burn them down.

My last two cents.


Cees

Forget the tea David, I think you should just take a hammer to your head! Sorry Cees, but it does come across exactly as David pointed out and seeing it in a thread almost always causes me to hitthe back browser button. Hell, why do you think I gave up on the Taurus thread...
Many modelers are not engineer types, they're tinker'ers; kind of like Orville and Wilbur. Hell, they kept their "real" engineer from learning to fly so he would'nt fly off on them; but that would not have stopped them from their tinkering. I'm not an engineer, but educated with highest honors and I can hold a steady conversation with those much more knowledgeable than myself, but I still tinker away. Making a mistake with the fuse rating is his danger, not yours, but to call him out as if he were lessof an individual than youis demeaning. As suggested, leave it alone from this point on (that means no reply or PM is necessary).
hook

Thanks god !!!