Wine Country Flyers Model Aircraft Club Forum

Hey fellas,

I was challenged the other night at the Board Meeting to start posting here on our forum.  I gave it some thought and I’ve come up with a plan that might be kind of fun.

I’m going to build a 29” WS (note--previously I said 38", but that is the length) foamie water plane called a Polaris.  It was designed by Steve Shumate as a simple foam knockoff of the Northstar.  Here’s a link to Steve’s build thread on RCGroups:
http://www.rcgroups.com/forums/showthread.php?t=922465&highlight=jetset44

Judging from the video on the build thread, this thing is going to rock!  Steve claims that his has a useful speed range between 10 and 70mph.

You can find the plan free online.  They build up really fast and the airframe is so cheap to build that it is practically free.  They are inexpensive to outfit, too.  I’m planning on having mine ready in time for the first Float Fly in May.

So here’s the trick:  if a couple of guys are inspired to build one of these then I’ll prepare the cut files so that Red can cut them for us.  Red has already generously agreed to do so.  

Any takers?  Here’s a photo of the finished Polaris:

Well, I guess I'm going to have to have one then........

Hah—I knew that you would jump!  That’s good ‘cuz now I don’t have to feel guilty about free laser time.  Drew just signed up to build one, too.

Just to sweeten the pot for anyone else, I can tell you a little about the Shumate designs.  My son Drew and I each built a Shumate T38 early last year.  The boy was 11 at the time and he had no problem tackling this project with just a little guidance.

We built our Talons from Dollar Tree foam poster board.  That means that the airframes cost about $5 each including the CF wing stiffener.  What can I say—I’m a tightwad.

These things scream, though.  We run 2200kV motors on 3S for unlimited vertical.  But the best part is that they are nimble enough fly on a softball field and they will slow to a walk.  In fact, they are so easy to fly that Drew maidened his by himself.

I expect the Polaris to perform similarly, but it will have the ability to scoot off of the grass/water/snow.  Should be fun.

Here is a pic of our Talons right after Drew and I knocked out back to back maidens.

One more shot of mine right after the paint shop.  She looks a little rougher now after a couple of hundred flights but is still a blast to fly.  She lives in my trunk and gets flown alot.

I'm in . . . I have never had anything to fly off water. This looks like a good one to start with.

And thanks Red for stepping up with the laser.

Jeff

Sweet!  I decided that if we hit 4 that it would be worth it to me to make the cut file.  But I didn't think that I'd hit that number in less than an hour.  This forum is even better than you guys said it was!

And check me out--I've got as many posts as Jeff already!

Anybody else?  It would be great to have a whole squadron flying this spring!  Proven kits for the cost of the foam . . . .

Paul

This build was fun and the plane flies great. Just be sure to add inlet and outlet airscoops to cool the esc i've seen a few smokers (ask Merle). Also dont use a cheap servo for the elevator you cant get to it without alot of cutting believe me I learned the hard way.

Thanks for that!  I remember a couple of foamie delta waterplanes at the Float Flies this year but I couldn't recall if they were from the same design.  Yours looks great.

I finished the tracing of the parts for the kit.  Just need to arrange them for the laser. 

Btw--I got a big bottle of CorrosionX for the dunking of our electronics.

Paul

We talked about this project a little bit at the Members Meeting this week.  Merle told us that he has built 5 of these things already for various people!  Flight reports were positive as well, especially in regard to how these planes will slow to a crawl for a gentle touchdown.

One question that came up was what does it cost to outfit one of these planes.  Based on what Drew and I did with our T38s I see it like this:

Foam      $ 2 for posterboard, Depron ?
CF tube.  $ 5 wing stiffener and hstab joiner
Power     $29 2200kV combo Grayson Hobby
Servos    $30 HS55s from Jake

So I'm looking at a $66 airplane needing nothing to fly but an Rx.  You could save $15 on servos but I'm trying to stop using cheap junk.  You could find a cheaper motor/ESC but we've been very happy with the system that we've been using. 

Red--what's Depron run?

Steve Koll jumped in at the meeting signing up for two kits.  I'll see if I can't complete the cut files next week while I'm on the road for biz.

Paul

Paul,

Count me in for a kit. While I haven't done much "building" to speak of, I figure even I can handle this.

Dave

Welcome aboard, Dave!  We'll keep you out of trouble. ;D

Oh yeah, Go Niners!!!

Paul

Paul,

A sheet of 6mm Depron 27"x 39" is about $10 shipped.

Red

Thanks Red.  I'm in Huntsville Alabama tis week but I got some work done on the Polaris last night.  It will take two sheets for all of the parts.

The alternative to Depron is foamboard with the paper removed for a buck a sheet. Red, don't you roll your eyes at me.

Paul

Got the cut files knocked out and passed on to Red.  He needs to massage them a little before his laser can run them but we should be close to cutting some parts.

I heard from Paul Eason last night and he is in for a kit, too.  To sweeten the deal, he offered up some of his personal Bluecor stash.  Bluecor is like Depron but used for construction.  Normally its quite a bit cheaper than Depron, but in this case it is free!  Thanks, Paul!

Before we start cutting we'll need to nail down what type of foam each builder wants to use.

Paul

Yep, I'm in.  If Red can cut Bluecore, I have a bunch of it and would be willing to donate to those willing to build the cut kit.  I've built a few foamies from Bluecore and using gorilla glue, and careful construction you can make a pretty nice planes.  I've built a "Twin" from "Foam and Tape" (one of the Sorilli (sp) brothers on RC groups), a Bluebaby (this didn't turn out well), and a couple of wings (I fly them at home all the time) with great success.  Some of you have seen the "Twin" fly - 4' wing span but only two 24gram blue wonders powering it.  I've also got a few tips for painting the foam's plastic coated side with Kyrlon Fusion.  Should be fun.

Sorry I haven't seen you guys much, but I've been a traveling fool gone every other week for work. 

Paul

Thanks again, Paul.  Red confirmed that his laser is perfectly happy to cut Bluecor.

The Twin is on my son's short list!

Paul

OK guys, get the word out... how many sheets of bluecor do you need?  I can bring them to the field on Sunday if you like.

Paul, I have templates to cut the "twin" out, let me know and you can have them.  I printed them tiled and then secured them to thin cardboard before cutting them out.  They fit fine, the build went well, just need some CF rod for the wings instead of the spruce spars they recommend.
PE

BTW, the "twin" flies better than they show in the video, it's really a hoot.  Your son will like it.  Paul

Paul, you rock!  Drew is stoked about the templates.  He really doesn't like tiling the drawings and cutting the paper.  Not sure why that is such an obstacle for him. 

Ok, from what I understand the Polaris lineup is like so:

1  Paul Kohlmann
1  Drew Kohlmann
1  Red Jensen
1  Jeff Penner
2  Steve Koll
1 Dave Mercer
1 Paul Eason

So far, that puts us at 8 kits but there is still time to add more.  We can easily get one Polaris per sheet of Bluecor.  Right now the cut file is set up for Depron sheet size, so if a builder prefers Depron that's fine but he'll need to get that material.  Drew and I would like to take Paul up on his offer for Bluecor.

Paul

Tiling isn't hard, I use a program called "scale and tile" that I downloaded for free from it's author on RC Groups (William Segraves).  Works well.  Not clear if this program is still available. 

Let me know how many you guys want and I'll bring the bluecor to the club Sunday if you'll be around.  I'll bring some extra sheets so Red can do some test cuts.

I would like one but need someone to build it for me please. Would also like to see the sample material.

LOL--I never said that tiling was hard.  Just that my 11y old hates putting the drawing back together and cutting out all of the pieces.  Must be a haunting kindergarten memory in there somewhere.

Morning MigRaptor. 

Paul

Paul, I knew it was your son that thought it was hard.  I'll give him the templates and enough bluecor to make a Twin, he's just got to finish it and fly it this year!  Tell him that's the deal.  Paul

Ok, Paul.  I told Drew the terms of the offer and he has accepted the challenge.

He says thanks! 

Paul

Paul, do the plans you gave to Red have the updated nacelle as shown in topic 392 on the RC Groups thread?  This would simplify the build.  Wow, 1000+ posts, there's a lot there...  I'm digging through them to see if there are other critical items we should discuss.

To be honest I didn't go through the 1500 posts.  Wow is right!  I converted the earlier drawing.  The mod isn't a big change, though.  I'm going to let it ride--day job is cutting into my modeling time :(

Paul

Should be fine, I'm looking forward to starting the build.  Wiley suggested we look carefuly at the cooling issues with the ESC burried in the airframe.  I have an idea on how to solve this.  I've got some pin-fin heatsinks that have super long fins on them.  Given that this bird requires a 30A ESC, these sinks would be fine (replacing the stock flat heatsink on the ESC) and could push through the top of the fuse to allow cooling and still provide a water-tight fuse (once you see them you'll understand what I'm saying).  I'll experiment on a HK 30A ESC that I have and see if it works.  If so, I've got a bunch of them from an old project at work and will hand them out to the builders if you guys want some. 

Great minds, Paul.  I understand completely what you are getting at.  I think its a good idea.  Attached is a Polaris with the same scheme.  Don't hold it against the guy that he put the US insignia on upside down. :(

Drew and I run the same 30A setup in our T38's.  The fuse is open from the inlets to the jet nozzles on those so heat isn't a problem.  I'm pretty sure that the Talons would go China Syndrome if the flow stopped, though.  Its just too much fun firewalling those things.

Paul

This is what the sinks look like (kinda sorta).  Heat one up and push it through the foam.

Kits are all cut. Get ahold of Paul Kohlman to get them while they're hot.   ;)

Hey guys, going to be around next weekend, can you bring them to the field?  I'm traveling this week so I'll tag up later in the week.  Thanks, Paul

Thanks for jumping on this, Red!  I'll pick everything up tomorrow.

Hi Paul--yes, I can bring the kits up to the field next weekend.  I probably won't get started before next weekend, so everyone has a fair shot out of the blocks. Probably;)

I'll print up an assembly drawing to go with the kits for each builder.  I'm also attaching the parts templates that show the position of the formers and such.  Shumate put together an excellent instruction guide that is found at the beginning of the original build thread.  The file for this is too large to post here, but here is the link again:
http://www.rcgroups.com/forums/showthread.php?t=922465&highlight=jetset44

Paul

I'm positive others will beat me out of the blocks, I'm going to finish the glider tug we talked about and "re-maiden" it this Saturday.  After that, finish the Crack Yak, and the big Sbach is going to be in-bound... lots of fun but I'll get to this before summer flying sets in.

Ok, all of the kits that have been spoken for have been delivered except the one for Mr. Eason.  Paul, I'll be at the Hobby Expo Saturday and may be working Sunday.  I'd like to get you your kit Sunday am, though, so let me know if you will be around.

Red cut extras so there are two kits left if anybody wants one.  As usual, Red's work looks great.

Paul

Paul - Pretty sick with a nasty head cold and don't think I'll make it outside much this weekend, so don't worry about the kit.  I will be at the club meeting (for sure) on the 19th if you wouldn't mind bringing it then, I would appreciate it.

Anybody started building yet?

Thanks PaulE

Sorry to hear that you are under the weather, Paul.  That's no fun.

Drew and I got started tonight.  The instructions begin with the wing, but Jake only had one CF rod for the wing spar when we dropped by the shop after the Hobby Expo.  I let him know that there might be a run on 'em and he told me that more will be in tomorrow. 

We cut strips of foam from the edges of the sheets to be used for reinforcing the inside corners of the fuselage.  The balsa stripper came in handy, although Drew has not quite mastered this yet;)

Next we glued the strips to the edges of the fuselage sides.  We used Gorilla Glue spread thin and activated with water.  Once these were dry we installed the fuse formers and called it a night.

Not a tremendous amount of progress, but we're moving!

I'll post some pics, but the site is acting up right now.

Paul and Drew

Here's Drew getting us out of the blocks with the balsa stripper.

Looks like Patrick got the file upload squared away.  He increased the allowable file size by a bunch.

Thanks Patrick!

Paul

Drew and I have been getting very small sessions in during the week but we're making progress nonetheless. 

We got our wings caught up by gluing the CF stiffeners into their respective slots.  Jake got plenty of .210" rod in for the main spar.  We used a 3mm flat stock that was on the rack for the angled stiffeners and they fit perfectly.

We are sticking with the plan for the most part, but I couldn't help but add a couple of mods.  The first was to add support rails and a half former under the battery tray.  A significant increase in durability in what I have found to be a problem area in other desigs for a very small gain in weight.

Once the wing is on it starts to look like it might amount to something.  In fact, it passed the glide test and it thinks that it is a Vulcan bomber!

Paul and Drew

Just got back from the field for a night flight.  Gorgeous evening but man my thumbs got cold!

Spent alot of time on the tail today.  That's about half of the build--seriously!  It starts with a sandwich of a slotted centerpiece with two sideplates.  The idea is that the slot forms a channel for the Motor/ESC and elevator servo wiring.  The top of the sideplates also form a platform for the bottom of the nacelle to perch on.

Once the sandwich was cured, the LE and TE were shaped a pocket was cut for the elevator servo.  The nacelle sideplates were dipped in boiling water and then shaped to fit the nacelle bottom.  The rest of the nacelle is pretty much of a box with reinforced inner corners. 

Couldn't help but put mine all together for a photo.  Drew is just a couple of steps behind.

Paul and Drew

Looking at using this motor:
http://www.hobbyking.com/hobbyking/store/__24239__D2826_6_2200kv_Outrunner_Motor_USA_Warehouse_.html (http://www.hobbyking.com/hobbyking/store/__24239__D2826_6_2200kv_Outrunner_Motor_USA_Warehouse_.html)
Reading some posts, it should be close to the Greyson motor, but less than 1/2 the price.  Worth trying since I had some other parts to order from HK.  Paul

Lost a week on the Polaris due to that whole work thing.  But I got back to town Friday and made the big push to get this project into the air.  Well, that happened tonight just as the sun was going down.  Pretty tough lighting for our little camcorder, but here is a little video of the first flight.

http://www.youtube.com/watch?v=1HyO8qfxtMg

I ran a 3S 1350mAh to minimize the wing loading for the maiden.  Probably wasn't necessary as she turned out to be very floaty.  Maybe the easiest maiden I've done.  My only gripe was that she needs some downthrust.  Might be due to the fact that I flew her with the upper fuselage uncovered.

Drew has slowed down on his due to competing interests, but now that he's seen mine fly he will probably get moving again soon. 
Paul

Here are some build photos to get things caught up. 

I'm giving plenty of detail on the controls, since I made some changes here.  I moved everything up to the top to keep the electronics and the control horns out of the water.  The electronics have been CorrosionX'd and the horns and motor mount were sealed with water-based polyurethane.

Also worth noting, I'm using silicone caulk to seal the entry points for the wiring and joints in the fuselage.

You guys building yet? ;)

Paul

Looking great Paul! No building yet for me. I'm buried up to my eyeballs at work, and not letting up for the foreseeable future.  :o

Great job Paul, good pics too. 
I'm like Red, I'm so slammed with work right now I can't see straight.  I expect to be home for a couple days next week and the I'm heading out again for more quality time with an airplane seat... I'll get to it, but it might have to wait, my 30cc Sbach came in today and I don't even get to see it until next Tuesday afternoon.  I did get the HK motor that I was referring to in my previous post.  It looks great and seemed snappy when I ran it on the bench with a 30A ESC and a 3S battery.  Not bad for $9.00.

Heya, Paul.  No worries--plenty of time between now and the end of Float Fly season ;)

I'm hoping to fly mine a bit more but by the time I get out of work its time for the nightflyer.  Maybe this weekend.  I need to aggravate Red a little more by flying her with her top off :o

Btw--Drew went on a mission last weekend and cut out all of the parts but the fuse sides for his Twin.  I think that he will be keeping his end of the deal.

Paul

Paul, when Drew starts in on the nose of the Twins, I've got some advice on how to do up the nose gear.  Probably don't want to mess up a long discussion about it on this thread but send me an email before he starts to glue the fuse together, I have some experience on how to do this right.

Spring break started for the kids today and I had a day off too.  Drew and I spent the first half of the day driving his Polaris to a maidenable state.  Like mine, he had the easiest maiden ever.  He launched off of the grass in a vacant field, took two clicks of aileron trim, and then flew it like he had a dozen flights on her.

Once he felt comfortable and we had a few photos out of the way, I had to launch mine too.  Nothing like two unmarked identical sky blue planes in an overcast sky at the same time. ;)

Here are a couple of photos of the boy in action.

Paul and Drew

Great work you two! 

Thanks, Paul!

Drew and I got so busy getting our planes in the air that we skipped over the last of the build photos.  Here are some details on the tip floats on mine (Drew's aren't on yet).  I used spray adhesive to build up the stack of foam just like on the nose cone.  Once set, the floats were sanded and fitted to the wing and then Gorilla Glued on.

I also added a heat sink to my ESC due to the feedback from Wiley, Merle, and others.  I picked up several types at HSC.  Man, that is a weird place.  I cleared away the heat shrink from the integral heat sink and epoxied a larger sink that will protrude through the foam fuse top.  Epoxy isn't the greatest choice for thermal transfer, but with a thin bond line it should be fine.  The ESC/sink was surprisingly cool after the flight with Drew, but that was with the fuse top completely open.  We'll see how it works when the ESC is sealed in its air/water tight chamber.

Just waiting on an Rx and then the fuse can be sealed up!

Have fun, Paul

Finally got our Polari closed up, hulls glassed, and paint on mine. 

Our simple heatsinks aren't as efficient as the pinfins that Paul E has, but they were easier to seal to the upper fuse. 

Once the tops were on, we cut larger battery hatches than the plan calls for.  I wasn't thrilled with the stock setup that required the hatch be framed with ply rails.  As for water leakage, we caulked all of the seams inside the battery compartment with silicone, so I'm not concerned about how much water gets under the hatch.  We also used paintable caulk around the wing and other joints that could leak into the fuse.

Next on the hit list was to glass from the nose to just behind the first step.  We hadn't tried fiberglassing before, but I watched Cole do it in his shop once.  We put down 3/4 oz cloth (won in the raffle ;)) and 20min finishing resin with a credit card.  Man, that worked like a charm! Really easy to apply and with a long finishing time.  We added a second layer just ahead of the step where the most damage was seen from ground operations.

After a light sand, I shot a coat of WBPU cut 50% with isopropyl alcohol over mine to seal the joints from water and to seal the foam from the solvents in the spray paint to follow.  That worked pretty well, but I did get some light damage to the foam when I applied the rattle can flourescent green.

Now I'm 100% ready for the pond, and Drew is right behind me!

Hey - that looks great.  I may do the glass as well when I start mine... well err... might be a while!  Good work you guys.

Drew and I met Steve Koll and his buddy Keith out at the pond today.  Beautiful morning for a mini-float fly.  And a great time to maiden Steve's Polaris.

Unlike Drew and I, Steve has no fear and planned to skip that sissyish maidening from the grass.  After checking our Polari for rates and balance and watching Drew take his for a spin, Steve went straight into the drink.  Initially he was a little underpowered, but after a prop change and some trimming he had his flying beautifully.

Drew and I snuck out to the pond on our own yesterday so that he could get his first water flights in without a crowd.  Not surprisingly, a day later he is better than his old man!

Here are a couple of pics of Steve including one where he is switching from missiles to guns.  A shot of Drew, too.

Paul

Hi Paul,
Thanks for meeting us out at the lake today. It was a beautiful day especially because the Polaris came back in one piece and it didn't sink. It was amazing to see your son Drew catch his plane in midstall by the way. Glad I had a chance to come out and get the Polaris all dialed in before the big crowd next week, at least I will look like I know what I'm doing.

Hey Paul, here is a pic of plane #2 for next week!!
Hope the weather is as nice as we had it.  ;D

First Float Fly for 2013 is tomorrow morning!  Drew got the bug to bash build a boat in time for the event.  Handy--he rescued my Polaris today after I exceeded my allotment of electrons.

Calalina looks great, Steve!

Paul

Drew and I have been flying our Polari every weekend.  Here's a little video:
http://www.youtube.com/watch?v=UceCMDJPXBI

Not quite up to Stychno's standard for pond video, but that's ok. ;)

Paul and Drew