AcroJo

My Feedback: (1)

Midwest Extra 300S. A good friend picked one up cheap. BME 44 on CH ign. w/ pitts, spinning a 22/8 Pro Zinger. It somehow found its way to my bench. Stripped the covering to find a good build that hasn't been wrecked. Weighed app. 15 lbs before some uneeded junk went in the trash. With swap outs, I can save weight with some components, depending on how deep his pockets are. I'm looking for your thoughts, tips or general suggestions on this model. Any do's, dont's or reasonable expectations will be appreciated. Thanks in advance, Joe

Rcpilot

My Feedback: (78)

Take a Dremel and sand the lite ply fuselage to enlarge the lightening holes. You can enlarge the lightening holes to within 1/4" of glue joints.

Lots of unnecessary wood in that fuse.

AcroJo

My Feedback: (1)

Your reading my mind! One of my first observations, now with confirmations! Cool. If it wasn't for a good friend it would not be on my bench. I'm commited to do it right. Went to the midwest products website and only found specs for the 300 XS. Are they similar?. Read some good stuff on it so far. If your experienced with this bird, and have any other advice I would really appreciate it. Must be a bear with the short tail moment. Any thoughts on counter balancing the elevators? THanks, Joe

blikseme300

My Feedback: (118)

Joe

Other than doing some lightening, don't change it. This is a very good and solid flying plane. I have had 2 of these and have a 3rd ready to cover. I generally fly 33% & up Extra's only, but this is a very nice "sunday flyer" sport aircraft. The XS is a derivative with minor changes. The most obvious is the change from a flat stab to an airfoiled one. This cured a problem with some of the early S's in that the stab would fail. There was a mod that Midwest brought out to eliminate this problem on the 300S.

Safe Flying!

Ratt Belly

What is the mod to prevent stab failure?

AcroJo

My Feedback: (1)

Thanks boys. Other than removing some of the bulk off the fuse the biggest offenders I've found so far is a 5.5oz aluminum spinner. 12.2oz aluminum LG along with 6oz of main wheels and axels. Wheel pants are substantial as well @ 2.5oz each. Thats just under 2lbs. right there and would be happy to half that. I'll be dumping the 4/40 linkage in favor of CF tube W/ titanium ends for a small savings. The servos are up to spec and weigh 1.73 on the heaviest one so I don't think it will get any better in that area.

RB, not sure of the stab mod, but this has guide wires installed. Joe

Floater-RCU

I think the flying wires were the answer. My early kit did not come with them but a call to Mid West and they were in the mail to me. Very nice people to deal with.

Floater

Ratt Belly

Wow, if you can shave a pound off, it is going to be a great flying airplane!. Mine is built pretty much box-stock (heavy) and it still flies great.

It is going to be my IMAC Basic Class mount this season.

Ratt Belly

BTW, mine came with the flying wires. You had me concerned there for a minute...

AcroJo

My Feedback: (1)

One pound is easy, I'm looking for more. One pound will come from just upgrading accessories. Tossing the pilot bust saved 4oz. alone. The LG is 12.2oz. I want CF gear, he wants to drill the existing gear. Its his dime. I've been 'hogging' today on the exterior. Once I pull the stringers on the bottom rear of the fuse, I'm goin in!!! I see more useless plywood on the bottom and in the mid section. So far with exterior holes on the sides and under the canopy, two more holes on either side of the engine box where it inserts into the first former and a plug out of the doubled ply on the front got me 5oz. Lotta work for five oz. I want at least one more ounce from the tail interior and bottom to make it worth it. Take a look. Joe

BTW, from scratch, with a little experience, I could see where this plane could be kept light. What I'm doing is getting whatever I can from the fuse, most likely 6oz. and the rest is coming from poor choices of components and a heavy hand where ever the original builder had to install stuff. The rudder servo mount on pull/pull was built like the Brooklyn Bridge.

CM1scw

I would like to include a few pictures of the plane as I received it. Disregard the date, I always forget to change it. I wish I had more to show the extent of the magic that Joe is doing. Today I told him that I was not going to fly it but display it as a Work of Art...


Danny

Don M.

My Feedback: (5)

One thing you have to keep in mind is that these planes tend to be tail heavy with the servos in the rear. I had one with a Brison 2.4 in it and was really proud of the weight I saved while building. When it came to balance it I had to add 1.5 lbs. to the nose, end result was 16.5 lbs., there went all my hard work.

AcroJo

My Feedback: (1)

Danny, I clean forgot to take any before pics, but will have plenty of after.

Don M, so far on the fuse the majority of the meat is coming out of the tail. The BME 44, steel pitts muff, with composite mount and bolts weigh in @ 54oz. Looking for an aluminum muff for a weight save and hopefully a quieter one. Anybody got a lead on a muff? Thanks, Joe

AcroJo

My Feedback: (1)

Got 6oz. Even looks light. 2lb. 14oz. bare fuze. Could have went more but decided 1/2 inch from the glue joints would do. I'll bet another 1/4 inch would have got 7oz. Too bad the original builder fuel proofed where ever he could with epoxy. Joe

AcroJo

My Feedback: (1)

Couldn't walk away from it till I was sure. Little more off the back and smidge up front. Shaved 6.6 oz. for a total of 2lb. 13.4oz. or 45.4oz. I'm thinking MonoKote is the lightest covering at my disposal, so the rest of the savings will come from components where there looks to be an easy pound. Joe

AcroJo

My Feedback: (1)

Pulled some balsa skin on the front of the wing to install CF tubes to eliminate the front wing bolts, 2 of four. Added some 1/4 inch ply behind the front plate, for a deeper shoulder around the tube, drilled for a 5/16 CF arrow shaft and made sure to continue into the hardwood piers that the front bolts go through. Next I took a rasp and angled the trailing edge of the wing, at the saddle and then added a wedge plate to the face of the #5 former. The angle will allow the wing to clear when inserting at an angle and leave nice lines when covered. Wouldn't you know it, I found another area to drill, the front former. In the pic you can also see where I added 1/4 inch ply washers to shoulder the front of the dowels on the #2 former. Joe

AcroJo

My Feedback: (1)

Okay, Danny ordered up some CF LG from graphtechrc.com, not bad @ $49.95. Then again, thats $50.00 to save 4.7oz. Going from original aluminum @ 12.2oz. to CF with the new 3D weave @ 7.5oz. Already have some 'titanium' wheel axels from pspmfg.com and that will take the 1.4oz. steel to .6oz. for both. The existing wheels are 5.2oz. and will go down to .8oz. with some ultra lites. Pilot is gone, so there is another 4oz. Total so far is 13.9oz. saved on just four components, add the 6.6 off the fuse and there is 20.5oz. or 1#4.5oz. saved with more to go. I know that the 5oz. wheel pants can go to at least half that.

Next up, new ailerons, extended inboard one rib length, or 4 inches. Not sure if I will extend the chord. New elevators with counter weights once the hor. stab. is shortened, same chord. New rudder with larger counter and extended chord.

Here is where I need some input, the 300s has a tall, short chord rudder with a small counter. My 3W Extra Fun, in the same size class, has a rudder that is 2 inches shorter, larger counter and deeper chord. Now they both pretty much are equall in area, but are configured differently. I know that the Extra Fun KE's like no other, but haven't a clue to the rudder performance on the 300s. Any thoughts on this? Thanks, Joe

AcroJo

My Feedback: (1)

Cut three inches off either side of the hor. stab. to accomodate the counter balance on the new elevators. Did not want to get into removing the balsa sheeting so glued in 1/4 X 1/2 balsa stock to cap the end and tie into the leading/trailing edges. Considering it is just a butt joint application on both ends, I cut a slot in each outside corner with a thin kerf finish saw and will slide in some gussets. The gussets are CA hinge material, doubled up, held in with epoxy.

I realize its only about seven hours, but if anyone can give me an idea of the rudder authority on this model it will help in my decision to modify it. Thanks, Joe

Floater-RCU

Joe, when I started building mine there was some talk in the threads about this plane not having enough rudder, so I added some cord and keeping the same over all height I moved some of the vertical stab into duty as counter balance. I haven,t flown it yet so I can't tell you how it worked out.
Floater

Don M.

My Feedback: (5)

As noted above I had a 300S several years ago and the reason I got rid of it was because it would NOT KE worth crap. I tried everything, more throw, stronger servo, reblanced, etc. I could not get it to hold a KE no matter what I tried. I had a thread going on the old RC Online site and no one could give me any suggestions except a larger rudder, I hated the plane so bad I stomped on it and threw it in the garbage.

CM1scw

AcroJo

My Feedback: (1)

Thanks for the input. The reason I threw this out is, a while back when trying to figure out the roll coupling on a UCD .60 I noted that aside from the dive to the wheels on rudder it would also drop the opposite wing. Left rudder = right wing drop, almost as if the overly tall rudder would twist the plane. As a result I chopped off the top of the rudder, app. 30 sq. in. and it pretty much resolved it.
Now, with the only thing to compare to in this size category is the shape of the rudder on my Xtra Fun, which is short and deep. I realize there is more involved here as in the aerodynamics of each plane, but the Xtra Fun KEs exceptionally well.

When the Midwest was in KE, was there resulting pitch, roll or both? Thanks, Joe

mike gruenwald

you guys are nuts! mine knife edges perfectly with 3% up elevator going both directions on the rudder. NO aileron mixing. balanced at 33% back of mac. built completely stock with moki 2.1
carbon gear and taiwheel assy. no added weight for balance. 15 lbs.

AcroJo

My Feedback: (1)

Mike, nice color scheme, looks sharp. I take it you have the 300s built stock and find the rudder to be good as is? If so, I will not mess with this one too much as the projected weight on this rebuild will hopefully be under 14lbs. If your setup is good @ 15lbs. then the weight loss should improve rudder authority. Thanks for the input. Joe

CM1scw

Interesting thing that there is no support for the tail group.......