Rob Schaffer

I've been building the Top Flite Corsair for some time now off and on as time and work permit. Lately I've been able to get more progress done and the plane is really starting to take shape with hopes of a June Maiden flight if all continues to go well.

The plan is to convert the plane to electric using an AXI 4130/16 Brushless Outrunner, 6S3P 6000 Gen II Lites from Thunderpower, Jeti 77 Amp ESC and a UBEC to power the onboard radio in leiu of a Rx battery.

This plane was a "gift" from an old friend who started the project years ago and then quit building shortly after starting. The only parts salvaged from his build were the rudder and elevator halves, as the wing was quite damaged from hangar rash and other unknown conditions. The fuselage wasn't built, and neither was the rudder fin or horizontal stabilizer, so that is where I began. While those were under construction I purchased wood and replacement parts from Top Flite so that I could build a new wing from scratch. The Robart 615's were also included, so that is why I am starting off with them, but I am going to add the RoboStruts for the appearance and shock absorption.

The goal is to incorporate a detailed cockpit using the optional cockpit kit, the radial engine, operating flaps, pneumatic retracts and operating gear doors. So far, things are coming along nicely, and I am very pleased with the way the project is coming together. Below are a few photos from early on in the construction. I think I am up to 55 construction photos taken, but these are just some of the select ones.

Rob Schaffer

The batteries are the LiPo batteries that have really changed the way the electric airplane can perform. In this case, I am using two 3S3P 6000 packs, wired in series to make the 6S3P. This also allows me to pass each one through a hatch just forward of the cockpit, and up against the back of the firewall to get them as forward as possible, yet easy to access. Stacked on top of eachother, they occupy nearly the same amount of space as the fuel tank would.

For the retracts, I followed some suggestions to mount them on the maple rails using blind nuts for easy removal and maintenance. This works well for the construction portion, and in the future too. The retracts will be entirely functional from the wing alone, so I don't have a disconnect valve to be worried about. For this, the retract valve is located in the center of the wing, along with the airtank. On the bottom of the wing, just set off-center, I have the fill valve and the pressure guage. Once the wing is on at the field, no reason to take it off to change batteries or access anything.

Rob Schaffer

I've followed a thread here on RCU by CorsairJock, as I'm sure many have, and picked up some infomation that I am starting to incorporate into the plane. One of those ideas was the cowl flaps. I downloaded the file and located the flaps on the cowl ring. I then proceeded to slice along the lines to create each flap, and heated them at the base with the tip of my soldering iron. After a few flaps, it started to take shape nicely and I like the way it turned out. Before priming and painting, I'll have to sand the burrs from the cutting saw, but I like the look!

For the first time, the plane sat up on it's own legs for a little while when I installed the retracts. This was before I plumbed the lines, but it really inspired me to keep working on the project. Now, the wing is nearly sheeted, and I'm sure it would look much better.

Rob Schaffer

Here are some photos of the "fun Sheeting" It took me a little while to get this part, but after breaking open another set of pins, I was able to get everything in place. I still have to cover over the retract location, but I thought I would leave it open till I have the retracts fit 100%, so I can work easily with the lines and things.

Here are two photos I found on the internet of a nice looking scheme. I have portions of the outboard panels without sheeting, just with rib-caps, so I can have the ribbed wing effect like the real one. I plan on covering with Flat Insignia Blue, Flat Dove Gray, and Ultracote white. I think the scheme will look pretty good that way. I've also just got the Major Decals Star and Bar Sets, for the 40 and 60 sized planes. This will save me some time in cutting out them from covering and applying them myself.

Well, thats about it for now, as a quick summary it probably isn't to bad. I'll be continuing this thread as I continue to work on the plane and start the finishing process. Hopefully I'll be able to keep making progress on it from now on.

[8D]

CorsairJock

My Feedback: (90)

Great to see you started a thread here (at RCUniverse), Rob.
Here's a photo of a restored full scale with tri-color scheme, to give you a good indication of what it should look like. NOTE: during WW II, these were painted semi-gloss, while many restored ones such as this one have gloosy finish.
2nd picture is of my AXI powered (same motor as yours) H-9 Corsair with same scheme.

Rob Schaffer

Tonight I was able to finish sheeting the bottom of the right wing, over the wheelwell and flap servo. This area was more difficult than I thought it would have been, but the glue is on and the pins are holding everything in place for the night. Don't know if I'll get to finish the left wing tomorrow or not, but I'll post new photos tomorrow anyway.

CorsairJock

My Feedback: (90)

Rob: I just took a good look at your rudder, and noticed that you haven't done anything to re-inforce it. Every Corsair that I have owned has tipped over at some point (tail comes over top, rudder strikes ground).

Sometimes due to pilot error (bad landing), sometimes because of landing gear malfunction (increasingly rare tho), sometimes due to wheel hitting a varmit hole in the runway, and sometimes for no apparant reason. Point is, the rudder will break when this happens, IF it is not strengthened.

Please read thru the Top Flite Corsair Mods thread and locate the area where I suggest rudder mods. My method not only strengthens the rudder, it also makes it appear more scale accurate.

Rob Schaffer

CorsairJock:

Thanks again for the tip. I'm going through that thread,... slowly, as there is so much great info available. I'm making a list of the things that I would like to do on my corsair while I still can.

Today I didn't get much time to work on the plane, as it was so nice out, my wife and I took the twins out for a walk and spent time with them outside. This weekend I did get some of the sheeting done over the one wheel area. This will be sanded smooth, and then I'm going to try to make gear doors following a way Luke did them on his Royal Corsair. Hopefully they'll turn out nice. I'll work on the other side this week and then sheet the belly pan. I've mounted the fill valve and air gauge just off center, so when I sheet the belly pan, I will have access to them.

I was cleaning up the one corner of my shop, and came across an old set of Vortec bombs and releases. I don't have a 7th channel to put them on, but I may still put them on the plane for looks. They seem short for the size of this plane but will still look nice I think.

Rob Schaffer

Descriptions to follow thursday,... it was a good building night (good 2.5 hrs un-interupted )

Rob Schaffer

Last night's work was great, and as you can see from the photos in the last posting, it is coming together well. I was able to sheet over the left wheel well, oil coolers, and the belly pan. There is still the small triangular wedges to install at the edges of the belly pan just aft of the TE, but that's a quick step.

The holes were pilot drilled for the wing bolts, so now I can enlarge them in the wing for clearance and then install the guide tube through the belly pan. The gray spot you see on the bottom of the plane is the location of the fill valve and pressure guage for the retracts.

I'll touch up some areas,.... and then it's time to put on the dust mask and start up the dust collector, then sand away! [8D]

As it is in the photos, it weighs 3 lbs 7 oz. This is with the 5 servos in the wing installed and the small air tubing / valve. I was hoping for a 3lb 8 oz total airframe weight including the cowling, but without any gear,... so I am pretty close to my initial estimate and goal. The AXI has plenty of power, so we'll still be ok if a little over the estimate.

Rob Schaffer

Been really busy with work and with installing a patio out back at the house, so not much was done recently. I have everything finished now on the wing and fuselage, and I have used some filler to help smooth out areas prior to sanding everything. I'm hoping to get a chance to sand everything by the end of the week, so I can then start working on the flaps.

Any tips or threads out there that talk about the flap setup? Looking at the plans, not sure how confident I am with the wire connection between the flaps holding up over time and staying true, cause I would think that the wood will soften a little around the holes over time? Must be a pretty proven system though as so many of the TF corsairs are using it.

I hope to share new photos soon,....

Rob

CorsairJock

My Feedback: (90)

Rob: yes the flap set-up looks pretty cheesy, and doesn't look like it would stand up to the test of time. But, it does work, and work well. One thing to be careful of tho: it is easy to get them setup so that the outboard flaps lower farther down than the inboard ones do, due to the geometry and angles. I put a small bend in my wires, so that they bend up right where they exit the flap that retrains them, thus eliminating that possibility.
The problem with having the outer flaps lower more than the inner ones: you reduce any washout effects, thereby creating greater possiblilty of tip stalls.
Thought I would share this link to the Hanger 9 Corsair electric conversion thread here at RCU, you might be able to pick up a few ideas there:
http://www.rcuniverse.com/forum/m_14..._1/key_/tm.htm

Rob Schaffer

Wow, been almost two weeks since my last post, and sadly, I have to say that not much has been completed on the corsair project.

I was able to get some sanding in, and things are looking really nice and smooth for the fuselage and tail feathers. I am working on shaping the tips a little better from the info here on RCU, and I hope to have the wing sanding done shortly. I picked up the fiberglass and some Z-poxy for an attempt at making the gear doors, which I'm pretty confident I can do, just finding the time will be the difficult part.

Hopefully a photo or two of progress will be posted shortly, but for now, back to work. [&o]

Rob Schaffer

Here's some updated photos... still one wing tip to finish, while the other is looking pretty good. I had to recruit some help from the crew, as I was sent to the garage to keep sanding since my daughters were in bed.

The pilot was testing out the space,.. and even though he looks good in place, he doesn't know that he will have to have an operation, rendering him unable to operate the rudder pedals..... double leg amputation [X(] In order to install the cockpit, save some weight, and be able to clear the two servos, it has to happen. Once the canopy is in place, you'll never know.

Rob Schaffer

And in this corner,.. weighing in at 8.6 lbs,... the unfinished project for the past two years,....

The Corsair!


Ok,.. well maybe it's been a long weekend, but I am at the closing stages before covering and installing gear on my Top Flite Corsair Conversion. Things are going well, and I am happy about seeing the total weight on the scale. I'm sure there is some error, as I was using a really cheap=o kitchen scale, and weighing all the parts individually. When I have it all assembled I'm going to hang it on a better scale.

Here's the breakdown so far. Using the AXI setup, I should have plenty of power and thrust. I'm going to read and use the E-Calc programs to see what prop will be the most efficient for me. Corsair Jock is flying his Hangar 9 Conversion with a 14" prop, and getting nice flights and good duration due to the low amps. Others are flying the 16" props, with more thrust, but then again, it's a warbird not a Funtana.

This week's goal,... Mold the gear doors on the wing. I've picked up some 1/64th ply to add to the fiberglass sandwhich and I have everything else ready.

DALE PABAJO

Nice corsair Rob nice work and detail it seem's you'r pilot is a little tight fitting in the cockpit? will the pilot and the topflite cockpit all fit in there nicely? a friend just gave me the same plane and �'m doing some resarch on it, just thinking of useing a 1.20 2 stroke instead,I was thinking on giving my corsair some lighting on the wingribs and formers. Hey where did you get the info. on the cowl flaps any how? can you pass it on to me? I was just thinking of a way to do just that. It wo'nt look like a corsair with out the cowl flaps.

Rob Schaffer

Thanks for the comment. The cockpit will be pretty tight, but the corsair has to have a pilot,... You'll still see a decent amount of the detail.

For rudder mods, wing tip mods, cowl flaps and a pattern, along with many many more pieces of information, search Corsair Jock, or for the Corsair Modifications thread started by him,.. it has got to be the best thread on the corsair to have read. Be sure to have a coffee or something nearby, it's a lot of reading.

*edit*
Here's the link [link=http://www.rcuniverse.com/forum/m_964836/anchors_964836/mpage_1/key_Corsair%252CMods/anchor/tm.htm#964836]Corsair Mods[/link]

Rob Schaffer

Installed the cockpit into the fuselage for good last night and it looks pretty nice. The pilot is in the middle of surgery now, and hopefully will be in the PACU shortly. I think I have everything ready now and marked out for the gear doors, and I'll get to try molding them tonight after working.

Rob Schaffer

Well, after getting home and finishing up some odds and ends, I was able to get some time in on the corsair. Here's a summary of what was accomplished along with some photos.

I am now ready to fiberglass the gear doors, using 1/64th ply cores. The monokote has been applied so the fiberglass doesn't bond to the wing, making it easier to remove after the doors are dry. I'm planning on 1 layer of 3/4 oz cloth, then the ply core, and then another layer of 3/4 oz cloth. Should result in a nice firm door, yet lightweight as well. If needed, I can always add a layer of glass to the door after it is removed from the wing if needed.

Also, the cockpit has been installed and the pilot has finished in the recovery from surgery and is testing out the fit of the cockpit. A little snug, but he'll get comfortable. Looks like he is inspecting the guages and one must have been sticking. A little tap on the glass and we are in good shape.

I painted the firewall to present a more finished appearance. The motor wires will actually not extend into the fuselage, as the Jeti controller will be mounted to the motor mount along with the UBEC for good cooling.

Should get to fiberglass next. Once that step is completed I'll fit up the plastic parts along the wing, and work on the flaps.

Rob Schaffer

Tonight I was able to get the wing bolt blocks in the fuselage drilled to the proper size, tapped, hardened with thin CA, and then I ran the tap through again. Looks nice and clean, and a metal 1/4-20 bolt threads smoothly, so the nylon ones should as well. I made the mistake on an earlier plane of putting the nylon ones in to soon to test the threads, and the CA locked it in there for good [X(] Learned my lesson from that one and haven't done that again.

The big item tonight was to lay the first layer of fiberglass using the Z-poxy, then lay the 1/64th ply core, and another layer of glass. Don't know if this will be enough glass or not, but it was worth the shot for the first time attempting this, and I"m pretty happy with the results. What's not shown is the transfer marks on the wing so I knew where to place the ply so I had adequate overlap and coverage from where the gear doors will be. I had my wife collect those plastic cards that come with CC advertisements, that worked great for smoothing out the epoxy and the fiberglass overtop of the wing and the plywood core. The 1/64th was thin enough to bend both ways fairly easily, which helped make a nice match to the wing shape. Overall, I like the process, and I think I could learn to glass a warbird pretty easily,... maybe the next one.

If all goes well, I should be able to remove things tomorrow before work,.. and then remove the monokote tomorrow night from the wing.

My wife wondered what the stink was,.. so I told her to grab the camera,..

Rob Schaffer

Looked at the doors this morning, and they looked good. I pulled the pins out and it feels like it will lift off pretty easily, maybe bringing some of the monokote with it. Didn't have time to really try, so I'll do that tonight when I get home.

Any recommendations on paint and primer to use? I was looking at the krylon series of paints at the store the other day, but didn't have a color swatch with me from the coverings. I was thinking of a white primer, gray and insignia blue, and then hitting them with a flat clearcoat to help match the flat coverings.

Do you find it best to paint the inside of the canopy or the outside? Outside may be prone to scratching, inside would leave the glossy look,....

CorsairJock

My Feedback: (90)

I started a thread awhile back asking the question: 'which house paint is best for painting warbirds?'. The majority stated that Behr exterior semi-gloss were the best, and the people at Home Depot were very good at matching colors. So, that is what I used on my electric powered Hangar 9 Corsair, and I was surprised at how well it worked. Water cleanup is a huge plus, in my book. Here is link to that thread, feel free to 'bump' it:
http://www.rcuniverse.com/forum/What...2604374/tm.htm

For fuel powered versions, which require more frequent cleanup, I prefer painting on the inside of the canopy. But with the electric powered ones, which rarely need cleaning, I suggest painting the outside of the canopy.

Rob Schaffer

Well, here we are,.. I'm pretty happy with the door blanks, and they removed really easily. A little heat gun action on the monokote, and it came off all in one piece.

The bottom side of the door blanks had some air bubbles between the cloth and the ply, but I think I can work with them and not have to mold new ones. After removing the door blanks and the monokote, I carefully started to remove the wing sheeting covering the wheel wells. A little sanding around the edge, and it's nice and smooth. Here's a few photos.

Next will be sanding and fitting the gun ports and the oil coolers.

DALE PABAJO

I guess your pilot fitted just about perfect,it would be really cool if there was a sliding canopy for it.

Rob Schaffer

Well, here she is, standing on her own legs. Checked the incidence tonight of the wing and stabilizer, looks like the stab is at 0 deg, and the wing is about 1/2 degree,.. I'm borrowing another incidence meter tomorrow night at the club meeting to help check the wings and the tail again.

I marked out the doors tonight, with a fine sharpie marker and measuring off of the plan and photos. I think they'll look pretty good.

Thanks to Corsair Jock, I have one of those TF static display props for when it is completed. Looks great having it on there now, let alone after I paint the prop and finish the plane.

Enjoy the photos. Tomorrow night is "show and tell" night at the club meeting, so I'm going to take the corsair and talk about the conversion to electric.