MinnFlyer

My Feedback: (4)

Ok, here we go!

Started out with the Fin/Rudder and Stab/Elevators.

With the pieces glued (CA) the end caps were glued to the Rudder and Elevators and they were all sanded to shape.

I just want to say that I have always really liked the idea of the end caps which greatly reduces the amount of end grain showing.

MinnFlyer

My Feedback: (4)

On to the Wing.

With the spar doublers in place, I nailed a Spar to the workbench (I like these electrical wire clips much better than pins)

Before continuing, since I want to move the retracts out by one bay, I needed to mark the Retract Doubler for the #3 rib to fit the #5 rib.

With that done, the ribs, TE and LE are installed, then with the TE weighted down against the TE Jig, I added the Shear Webs and made the pocket for the Wing Joiner.

MinnFlyer

My Feedback: (4)

I plan to fully sheet the wing and add flaps, so I had to do things a little out of order from the manual. Namely, I need to sheet the bottom of the wing first so I can route the aileron pushrods.

So at this point, I had to install the retract rails.

Again, instead of adding the rib doublers to ribs 3 & 4, I added them to ribs 4 & 5.

Then I placed a retract between the two rails (With a small spacer shim which is just barely visible) and once they were lined up, I tack-glued them together so they would hold their relative position while I installed them.

Once they were epoxied in place, Tri-Stock was added to the undersides and after the epoxy had set, I knocked the braces off.

MinnFlyer

My Feedback: (4)

Now the front-bottom sheeting is glued to the leading edge and the forward edges of the ribs.

While the LE dried, I dampened the outside of the sheeting with water and let it sit for a while before continuing.

Once the sheeting was attached to the rest of the rib fronts and spar, I took advantage of the open top to reinforce the glue joints. Too bad you can't do this to the sheeting on the top side too!

MinnFlyer

My Feedback: (4)

Ok, now I got a little crazy.

I went to the hobby shop last night, and they didn't have any 3/32" sheeting (Except in 2" wide) So I had to make a decision.

I decided that even though it would be a lot more work, I would sheet the rear of the wing with 1/16" sheeting, but to make up for the loss of thickness, I placed some 1/32" strips on all of the rib tops, the spar and the TE.

It was a lot of work, but since it's only a base for the sheeting, none of the cuts had to be precise, so it wasn't too bad.

Also worth mentioning... I glued all of the strips down with wood glue with a drop of CA on the ends and in the middle. This kept the pieces locked in place so no pins were needed. Wood glue alone would require pins or weights, otherwise the 1/32 balsa is so thin that wood glue will cause the strips to warp.

MinnFlyer

My Feedback: (4)

Next I edge-glued a 6" and 2" wide sheet (The hobby shop didn't have the 4" sheet I wanted)

Then I glued the sheets in place.

I used mostly wood glue, but I put a drop of CA on the spar at each rib so I could secure the spar area first.

Once that was secured, I layed the sheeting down over the back of the wing.

And look!!! I finally found a good use for the AMA Magazine!

vmsguy

Cool!!!

I've been waiting for this thread!

Retracts... (Why am I not surprised?) Moved out a bay. Question, I was planning on going with fixed gear (I could change my mind though) do the wheels on a fixed gear set up end up in the same place as wheels on a retract system? What I'm getting at, should fixed gear setup be moved a bay wider as well???

I haven't opened my kit yet, are the front of the wings sheeted? Or none at all???

Keep up the pictures...!

green river rc

My Feedback: (2)

wmsguy, go for the retracts!

I'm building one also, OS .75AX, Futaba gear, Robart retracts, might do flaps. Started Christmas day, target test flight was New Years..might have to push that up a little.

Hey minnflyer, What's the reason for moving the gear? I like the romex clips but how do you remove them after the top spar and sheeting in on, what about web shears?

Keep up the good work!
GR

green river rc

My Feedback: (2)

OOPS...picture

r2champion

Great thread Minn...My wife was gonna get me a US 60 for Christmas but they were out of stock [:@]. No chance you or Ken could spare one of those kits you all have hoarded up could you[8D]??? Just kidding, hopefully I can find one on ebay and I will use you're thread as a great resource. What do you plan on powering it with? I have an extra Tower 75 waiting for mine...if I get one! I am sold on this motor after using one in my Hog Bipe. Maybe I will find the time to do a build thread whan I get one. Keep up the the great pics, I'll be watching!

r2champion

Also, I like you're use of cable tacks for holding the wing spar in place. Excellent idea that I never thought of!

MinnFlyer

My Feedback: (4)

Fixed gear will wind up in the same place as the original retract location. Wouldn't hurt to move them out. But if you do, AND you plan on tirke gear, don't punch out the lightning hole in rib #5. You'll need the extra strength.

The Cable tacks work great. I've been using them for years. When Ken was here last summer we used them on the trainer we built and he really liked them too. You have to nail a few holes in your building table, but that's why I did the wings on my "other" table (Didn't want holes in the table I use for reviews )

The pics here (Where the cable clamps are used) were on the first wing panel. On the second one, I put them outboard of the ribs, so I only had the center one to deal with when it came time to do the shear webs (I usually do this, but it's been so long since I actually "BUILT" something that I must've just had a brain fart).

Anyway, for the shear webs, you put all of them (that you can get to) in place, then remove the clamps and do those (3 on the first wing panel, but only 1 on the second)

VMSGUY: The front of the wings are normally sheeted, but the back is normally a 1-1/2" sheet at the TE and cap strips (See Green River's Pic).

Green River: I move the gear out one rib because to me, they just look too close together. Moving them out gives more ground stability. It also gives a little more room to make the struts longer, but I don't recommend going more than about 1/2" longer than stock or they will bend too easily.

Note to anyone doing the flap mod: If you go with one servo and flexible pushrods, remember that on two ribs (Probably #6 & 7) you will want to cap-strip only the forward half of the ribs and sheet between the rear halves of them to give a solid balsa sheet from which to exit the pushrod.

I will be using an OS 75AX

r2Champ: This is the only 60 kit I got, and Ken (The man responsible for the re-issue) didn't even get ONE!!! (I'll let him live that down in a few years ) BTW, if you've got a good 46 or 50 they still have some 40 size Ultra Sports. THis is my first 60 size, but I've built 4 of the 40 size and it is fantastic.

Tee Bee

Thanks for this thread, Minnflyer! My US60 has been waiting in the box since June, along with the 3DX retracts you designed. Should be starting it in a couple of months and plan on some of the same mods you're doing. I'll definitely benefit from your experience. Thanks, again.

vmsguy

I have a set of GP 40 size mechanical retracts... I'd have to get larger size... I am reluctant to get retracts, I fly off grass. I'm a little worried about beating them up too much.

But for sake of argument, where can I get the Minflyer's retracts? And what are suitable substitutes? I'd like to do mechanical retracts, is the kit built/designed to lend itself to mechanicals? And finally, can grass and retracts really play nice together???

I presume, you'll be using separate servos (1 per wing) for the ailerons? With retracts, flaps, (smoke?) won't the fuselage get a little crowded? Will the plane get heavy?

green river rc

My Feedback: (2)

I have the Robard 90* 608 HD (heavy duty), they are very robust with a 3/16" strut. The US60 does lend itself very well to retracts, and far as being crowded...not at all. 5 servos (without flaps) typical 3 in the fuse side by side, elevator, rudder, throttle, 2 in the wing, aileron and retract. In case you didn't know mechinal retracts takes a special 180* servo also. Here in a picture of my wing servo arangement as per plans. Mocked up it worked very well with no binding it interference. The struts are kinda stubby also reducing the amount of wobble in will have on the runway. Notice how the retract servo is recessed into the wing.

mikenlapaz

Will be following this thread closely as we got a few of the US40 delivered here a few days ago.

This is the info on the retracts. Their site showed "Out of Stock" Below is email and reply FWIW.

To: [email protected]
Sub: you show out of stock
Item: Home > LANDING GEARS & WHEELS >
Mechanical Retract Main Gears (2-PC SET)
When do you expect to have them in stock? Will you send an email when they arrive please.

Replied:
mid feb
Thanks,Paul G http://3dxhobbies.com 732.406.5726

These axles should work with the 3/16" struts. Look on 3DX site and could not locate any. http://www3.towerhobbies.com/cgi-bin...?&I=LXK183&P=0

Pictures and comments are great.

MinnFlyer

My Feedback: (4)

I fly off of grass too and I have ripped out more than one retract in my day.

So I bought some RoboStruts. I've used them on several review planes lately and I'm pretty impressed. They're not cheap ($40 each) but I do believe they will provide the extra shock absorbsion I'll need.

And don't worry about weight. The Ultra Sport is one of those planes that flies better with a little bulk behind it. That's why I'm not afraid to fully sheet the wing.

green river rc

My Feedback: (2)

Hey Minnflyer, where you at on yours? Mine is almost completely framed up. It's pretty much stock, haven't decided on flaps or not though.

I have never flown a U.S, do they come in hot or do they float right on in. We fly off a 300' blacktop strip and planes that come in hot are sometimes a bit of a problem getting them to slow down. I have a GP .40 size Extra that comes in pretty hot, it sometimes flips over in the grass at the end of the strip. If I knew how it came in it would help decide if I need flaps or not.

MinnFlyer

My Feedback: (4)

I didn't get too much done today, Cut the sheeting for the retracts and that's about it. I'm kinda on hold now till I get my Tower order with the aileron pushrods.

Yours is looking great!

green river rc

My Feedback: (2)

Are your ailerons and flaps going to move together (spilt ailerons)? Kinda like a H9 Ultra Stick...flip the switch and have regular flaps?

What about how they land, do they come in hot or have you flown a 60? Not trying to hijack your thread.

fstevenj

Couple of questions. I am just behind you on this build and am planning on the same setup except with dual aileron servo's. How do you know where to locate the gear blocks when they are one bay out? How do you know where to cut out the sheeting for the gear and does it end up recessed within the skin when installed? When do you cut out the ribs for the wheels? I assume you will show all this, but I would think some of this would have already been done?

vmsguy

Another question...

I presume you're making this a tail-dragger... Did the kit come with tail gear? And are you using it? Or are using something other than stock? (I'm guessing you'll be using a Sullivan tail gear.)

MinnFlyer

My Feedback: (4)

green river, The flaps will not work with the ailerons. They will be completely independent. I did this on all 4 of the US40s I've built and found no loss of aileron control. However, one difference I have found between the 40 and 60 is that the 60 has you cut 2" off the outboard end of the ailerons and glue them permanently to the TE. I don't intend to do this, I'm going to leave the ailerons their full length.

As far as "Landing Hot", If it lands too hot, try moving the CG back a little, a nose-heavy airplane will not slow down well. The flaps will definitely slow it down nicely.

fstevenj, You locate the retract blocks the same way you do in the original location. You can see in the picture above that the rear block goes against the spar, and as long as the two blocks are secured together, the front block will automatically align.

I will soon fill the forward bays with foam, then when the top sheeting is added, the retracts can be put in place and their outline traced on the sheeting so it can be cut. And yes, everything lays below the sheeting.

I'll attach a pic of one of my US40 wings so you can see the final result.

vmsguy, I am going to use a modified Great Planes landing gear (GPMA2838) It's a little too long, so I plan to cut it down. (See pic)

Insanemoondoggie

The threads looking great , and man , you build fast !

In your Ultralite wing pic , are those Dubro control horns ? And do you like them ?

Instead of flaps , would flaperons work just as well ?

RCKen

My Feedback: (9)

Robbie,
I've tried using flaperons once, and ONLY once! IMHO they cause more problems than they fix. On the Ultra Sport definitely do the flap conversion that Mike is doing, but stay away from flaperons. The US flies great without flaps so you'll be fine without them. But if you do add them it does make a fantastic flying plane even better. I was actually against doing the flaps on a US before I went to Minnesota last spring. In fact (Mike, correct me if I'm wrong) I think my exact words to Mike were something like "Are you on crack? Flaps on an Ultra Sport? What a waste!!!". Then I flew his Ultra Sport. OMG!!!!!!!!!!!!!!!!! what a difference they made. it's definetly worth adding flaps!!!!

Ken