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buzzltyr
07-23-2006, 05:52 PM
I've been working on this one for awhile (since late March, I think), and am almost ready to start covering. I can't help but show it off!:D

It has a 60" wingspan, four dual IPS's, and weighs 21 oz at this point. I'm hoping for an AUW of 27-28 oz, including a 2S battery.

Mark

Bill G
07-23-2006, 10:40 PM
I like the plane, and the idea of 4 dual LPS motors. They're still pretty light in pairs, and the net sum should be a good result, and will sound really good.

WWI Ace
07-24-2006, 11:58 PM
Whew!!! There's alot of stringers in that plane!!! Great work. I don't blame you for showing it off. I mostly build WWI kits but this one is cool too! What scheme are you going to do? Let us see it when it's done and maybe some video. I'm sure it will be an impressive flier. Steve.

buzzltyr
07-25-2006, 01:49 AM
Thanks for the compliment, Ace. A lot of little tiny sticks (actually, given the size of the model, not so tiny sticks).

When I'm done, I hope it will look like the attached picture. Another American giant gone by the wayside. The name of this one, btw, was "Clipper Splendid".

Mark

Bill G
07-26-2006, 05:34 AM
Thanks for the compliment, Ace. A lot of little tiny sticks (actually, given the size of the model, not so tiny sticks).

When I'm done, I hope it will look like the attached picture. Another American giant gone by the wayside. The name of this one, btw, was "Clipper Splendid".

Mark

Are these really gone by the wayside? I'm not near any airports, but I went to an airshow at Pittsburgh Intl lately, and was amazed to see all these prop airliners coming in. They were commercial, not part of the show. I'm not sure what they were. I thought the larger commercial airliners were all jets. Apparantly they still fly some larger prop transports.

E-Challenged
10-31-2006, 04:16 PM
At least your DC-6 isn't in the 3D section:D

rcers
10-31-2006, 04:20 PM
Mark it is stunning.....keep us updated - I like the PanAm scheme.

Mike

buzzltyr
10-31-2006, 06:13 PM
Mike, check Pat's RCG build thread. It lists all of my current trials and tribulations, including my third maiden attempt this morning. Any and all thoughts and advice are welcome on my issues with getting this one in the air.

Thanks to Callie, the PanAm scheme really came out great (and it was easy to do, besides).

Mark

rcers
10-31-2006, 06:30 PM
Mark - I PM'd you - baffling.......

Mike

BobCMay
12-10-2006, 11:45 PM
I have had a DC6 in the barn for over 35 years. It is a 6 foot U-Control model probably from a Eureka kit. I am planning to make it an electric RC model.

It is balsa covered and now weighs 8 pounds and has one .60 Olsen engine left in it. I want to use 4 brushless motors in it. Someone in RC Groups (Metowcoupe) says they should each be 200 watts.

I probably should strip the balsa and cover it with ultracoat (or something like it) to lighten. I might have to reinforce the superstructure, though.

Got any ideas? :rolleyes:

buzzltyr
12-11-2006, 12:40 AM
Hi Bob,
The 200 watts per engine, for 800 watts gives you 100 watts/lb. That's good sport level performance. You might be able to get away with 80 watts/lb, which takes you down to 160 watts per motor. Not much difference, really. For saftey's sake, I'd probably stick with numbers around the 200 watts per. So you have any idea what the wing area is?

My 60" DC-6 ended up at 31 oz for an AUW with battery, and just about 10oz/sq in for a wingloading, so it flew very much like a parkflyer.


As a CL model, I would assume that it is elevator only? If so you really are going to have to strip it in order to put the other control surfaces in place, anyway. When you do that, I'd look to lighten it as much as you possibly can. That will help with motor/battery weight. The other issue is the size prop you can spin. I'm guessing probably a 10" is maximum? The motors would need to be selected to spin whatever size prop would fit, that will get you up into that 200 watt range.

The good news is that there are a lot of inexpensive brushless motors out there that will be in that range. The killer is a)you'll need four ESC's, and b)the wiring of multiple ESC's can be a little confusing. I would think, using motors of that size, you are going to need two batteries, one for each set of motors or wing. I'm not sure, at the weight yours is at, that I'd even think about brushed motors.

If you read my posts on RCG, it should be evident that I am hardly a multimotor guru.:D But that's about what I think you'd need. Hopefully you can get a couple of pounds out of the model, and that would help alot.

Do you have any pics? I'd love to see it.

Mark

BobCMay
12-11-2006, 02:10 AM
I was half way through the reply for your post and hit a wrong key and lost the whole thing so I’m going to write this in Word and paste it into the post.

To start again for the third time:

Since I posted “Fellow DC6 Builder” I’ve been reading Pat Tritle’s RCG thread on building his DC6 kit. I only got through a few pages of the 30 page thread. His kit is very interesting. How does he get the weigh to less than 2 pounds?

You have a thread there too don’t you. I read about your trials and tribulation, too. That’s at least the problems I would have as I am a rank armature at this.

Where can Pat’s kit be bought? How much is it? It might be cheaper to build his kit than try to resurrect my DC6 considering the extra cost of motors, ESC’s and batteries for the extra weight.

My DC6 is still in the barn. I haven’t taken a picture of it since I moved to the farm (36 years ago). It is so dusty you wouldn’t be able to see it in a picture now. It was damaged in moving to the farm and it isn’t very pretty anyway. Six inches of a wing tip was broken off and the plastic cockpit and 3 cowlings fell off. That’s minor compared to what must be done to convert it to motor driven RC.

Right now I’m working on a small Piper J3 (brushless driven) and I want to finish it before I start on the DC6. As you might suspect, I’m going to have to get an expert to fly the DC6. Maybe in a buddy hookup if I’m lucky. I don’t even belong to the club yet or am I a member of the AMA. I will have to join if I do this DC6 thing.

Didn’t I read somewhere that there are brushless ESC’s that can drive 2 motors? They’d have to be double the wattage but that’s less than 40 amps for 2x200 watts at 12 volts (assuming 3S lipos) isn’t it? Or am I all wet?

buzzltyr
12-11-2006, 03:13 AM
Bob,
The DC-6 short kit is available directly from Pat Tritle. You can email him at: patscustommodels@aol.com. My recollection is that the kit (includes cowls and scoops) with shipping was just under $100, but you'd have to get a current quote from Pat. You then need to supply all the sticks, LG wire, wheels, hardware, etc. Pat has a list. You also get a full set of plans.

Yes, I posted in Pat's thread on my build and the debugging of my model.

The low weight is achieved by the type of construction. The entire fuselage is 1/8"sq sticks and stringers on 1/16" quarter formers. While it isn't hard to build, it does take awhile. My DC-6 was heavy, compared to Pat's prototype, which came in at about 26 oz, iirc. But I was using IPS dual motors, which added about 2 oz to the weight, over the single IPS motors. I also had to beef up the motor mounts to handle the additional thrust of the duals. The rest of the weight increase was just me and my building skills, most likely.

There is some dispute about running two brushless motors off of one ESC. It can be done. I'd suggest you go to castlecreations.com, go to Media, and read the March, 2006 Joe's Jabs in the Castle Scribe. It deals specifically with running two brushless motors on a single ESC. As I understand it, ESC's are constantly keeping track of the motor's rotation. According to Castle, if the motors are very closely matched, you can run two off of a single ESC. If they are not closely matched, the ESC can't operate them properly. If you want to look at a major multimotor project, go to RCG and do a search on threads by Martin Hunter, and Antonov. As I recall, he built two of them, and they have 7 or 9 motors (I can't remember the exact number). Martin used a 1 motor/1 ESC setup, and still had problems with getting all the motors to run in synch.

Your numbers are correct. If you use 10 volts as the average for a 3S lipo, and 20 amps, you are at the 200 watt figure. So for two motors, a 40 amp ESC would work. But that also means you are looking at a 3s 4000 mAh 10C battery to support them at WOT. And you'd need two of those batteries for the two, two motor systems. You couldn't pull 80 amps out of a 4000mAh battery (unless it were a really good 20C battery).

I don't know if any of this helps you. But I do know that if you want a DC-6, electric powered, that Pat Tritle's kit is probably the way to go. It is well designed. I am no wiz at building, although I enjoy it immensely, so if you decided to do one, I'm sure you could. Pat supports his kits, and answered many, many emails from me when I was confused about what to do with a particular aspect of the construction.

Out of curiousity, whose J-3 are you building? I have a beta build thread here (and on RCG) for the new 48" Mountain Models J-3, which was just released. It's a really nice, light kit, and a very straightforward build.

Mark

BobCMay
12-11-2006, 05:14 AM
Hi Mark,

Wow! Thank you for your fast reply. Youíve given me so much information it will take me a while to assimilate it all.

What is an IPS motor? I gather it is a brushed motor. Is there a glossary of all these terms somewhere? I get lost in all the abbreviations. I can figure out a lot of them but some I canít.

Does Pat supply die cut parts he talks about as part of his kit? (ribs, etc.)

The J3 is an old Ace RC Simple Cub with a 33 inch wing span. Iím doing it to get back into building from scratch and to get used to flying with ailerons. Back in 2000 I built a park flier and a Gentle Lady sail plane. It was an ARF, if you can believe that. Then I built a Graupner Thermik, another sail plane.

I havenít figured out the wing area or the DC6, but it is probably around the same as Patís or a little more as the wing span is 6 feet.

Itís midnight here, so Iím going to end this here. Iíll get back to you when I figure out all the abbreviations and look up all the references you gave me.

Thanks again for all the information.

Bob

buzzltyr
12-11-2006, 11:48 AM
Hi Bob,
The Tritle kit includes laser cut ribs and formers, and some of the internal structure for the wings, landing gear mounts and tailfeathers. You have to supply all of the strip wood for stringers, etc., along with all of the hardware. Basically, all of the "hard to cut yourself" stuff is done for you.

Sorry about the IPS designation and not explaining it better. Yes, they are small brushed motors. The most ubiquitous ones are the ones manufactured by GWS. They come in a variety of gear ratios, to swing different sized props. The Dual IPS' have two of the little motors in tandem, so while heavier, they have more thrust. They are readily available from most of the online vendors. I got mine from Balsa Products, bphobbies.com.

I don't know of a glossary. But if you look around the web and have questions, feel free to PM me or post (here or at RCG) and I'll be happy to help in any way I can.

Mark

cyclops2
12-11-2006, 09:17 PM
Bob May.

Do some VERY CAREFULL looking at your U C plane.
They used to do many things to twins on UC, to keep the lines tight.
Inner wing sections wider.
Higher lifting airfoil on inside.
Engine mounts aimed to outside of the circle and not both the same amount.
Verticle stabilizor angled to inside of circle.
Best one I heard of was the inside wing panel glued to the motor joint so the rest of the plane pulled outward.

Really check eveything out before starting the RC conversion.

BobCMay
12-12-2006, 03:46 AM
Hi Mark,

Thanks for the advice. I will look closely at all your mentioned UC modifications. I am still thinking of Pat's DC6 as being a better choice. It would probably be cheaper and easier, but I'm still looking at brushless motors. I haven't read through Pat's build yet. He may expain why it is better to go with IPS's (probably simplier, lighter and will all stay on together without one quitting). I still don't know what the letters IPS are an acronym for. (You told me they are small brushed motors). I found out what WOT and iirp are.

Thanks again

Bob

buzzltyr
12-12-2006, 01:27 PM
Bob,
Here's a link to the GWS website on the IPS motors. IPS stands for "Indoor Power System". The IPS singles (what Pat Tritle used in his DC-6) are at the top of the page, and the dual IPS are at the bottom (what I used in mine).
http://www.gws.com.tw/english/product/powersystem/ips.htm

The IPS motors were sort of the ubiquitous brushed motor for small parkflyer type aircraft (8-10 oz weight). For their size, they are reasonably powerful and light. They are also pretty cheap, and can be found online for $12-15. The dual IPS cost me just under $22 each, for comparison.

The advantage of brushed motors is that you can wire them in parallel, and don't have problems with the ESC's having to keep track of their rotation. Wired in parallel, the amps are additive. So with my duals, at about 3.5 amps per nacelle, I was pulling about 14 amps for the four motors (4x3.5). I used a 20 amp ESC (Castle Creations Pixie 20), so I had some capacity left. The Pixie 20 also has a programmable low voltage cutoff, so when I switched from a 2 cell Lipo to a 3 cell Lipo, I was able to reprogram the cutoff.

If you have any other questions, ask away!

Mark

BobCMay
12-12-2006, 01:53 PM
Hi Mark,

Thanks for the info. I'll look up the motors. Right now I'm feeding the horses and have to get back.

Thanks again,
Bob

Bill G
03-05-2007, 08:26 AM
Are You Going to Install Floats-Cool!!!!:DI don't see why it wouldn't work? It would be pretty cool!:cool:

Bill

E-Challenged
04-18-2007, 03:40 AM
I would guess that converting the heavily built old UC model to electric power would be quite expensive and it would probably not be a successful model in terms of easy flight performance and longevity. On the other hand Tritle's DC-6 is a large stick model with sticks showing through the semi-transparent covering. Pat's DC-6 is typical of his designs which some, like myself, find a little too lightly built and some judicious beefing up in certain places doesn't hurt. It is easy and cheaper to use four brush type motors wired in parallel on a single high capacity brush type speed control than multiple brushless motors on multiple brushless speed controls. Pat used a single 2-cell Lipo pack in his prototype mounted in a compartment with a hatch on the underside of the wing. Pat has a lengthy DC-6 build thread on RC Groups, E-Zone, Scale Electric forum and video clips of the DC-6 flying on Manzano Laser Works website.

Bill G
04-18-2007, 07:39 AM
I would guess that converting the heavily built old UC model to electric power would be quite expensive and it would probably not be a successful model in terms of easy flight performance and longevity. On the other hand Tritle's DC-6 is a large stick model with sticks showing through the semi-transparent covering. Pat's DC-6 is typical of his designs which some, like myself, find a little too lightly built and some judicious beefing up in certain places doesn't hurt. It is easy and cheaper to use four brush type motors wired in parallel on a single high capacity brush type speed control than multiple brushless motors on multiple brushless speed controls. Pat used a single 2-cell Lipo pack in his prototype mounted in a compartment with a hatch on the underside of the wing. Pat has a lengthy DC-6 build thread on RC Groups, E-Zone, Scale Electric forum and video clips of the DC-6 flying on Manzano Laser Works website.

That's pretty much my feelings. The designs are light and thus fly well, but don't ever crash them in even the slightest way.:eek:
On the other hand, I tend to built overly reinforced planes. I have a converted Guillows DC3 that still needs to be flown, 2 years later.:eek: I even added span to it, but with sheeting, it is around 15oz, and has a loading of near 20oz/sq-ft, if I remember correctly. Maybe I'll try rog, since it has a steerable tailwheel. No hand lanch and crash, however.:D

I would like to see this DC6 completed and hear about how it flies. If I had thought about it, I may have bashed my DC3 into a DC6, and used 4 short can Feigao IPS motors and would have come it a good bit lighter than with the 370 brushed motors. Maybe even use brushed IPS and use a single 15A ESC. Another cool thought would be to bash a GWS DC3 into a DC6.

Bill