Gentle Lady restoration

[kkelly]

Last year I did my first balsa build in 30 years. Now I'm revisiting my first ever balsa plane, a Gentle Lady. She's been in closets and storage since the early-1990s and is worse for the wear, but I think I can make her beautiful again.

Here's what she looks like right now:

I did not know what I was doing when I built this plane. I can see a lot of mistakes that hopefully can be fixed. The fuselage is in decent condition aside from some crooked formers that 12-year old me installed and some cracked sheeting. The vertical stabilizer obviously needs to be fixed or rebuilt. I still have the plans, which are in very good condition given their age and the fact that back then I wasn't all that good about not glueing planes to them, so I can fabricate any new parts I need. The horizontal stabilizer looks to be in perfect working order.

The wing is a little more beat up but still salvageable, I think. You can't really tell from looking at it, but both outer panels have partially broken loose. This is probably the worst spot:

Something thought my plane tasted good:

I'm going to assume that was done by our dog or cats and not some random ravenous rodent that found its way into my storage space.

I'll post more pictures once I remove the covering and do a full inventory of the damage.

I may convert the outer wing panels to be removable per the plans. I need to do a test fit with my car, which is much smaller than the minivan I used to use to get to the flying field.

I want to make this plane a motor glider, but I like the look of the nose and don't want to remove it. Back in the day I built the over-wing power pod but never flew with it. I may experiment with an electric version of it.

 

[Mr NCT]

Last year I did my first balsa build in 30 years. Now I'm revisiting my first ever balsa plane, a Gentle Lady. She's been in closets and storage since the early-1990s and is worse for the wear, but I think I can make her beautiful again.

Here's what she looks like right now:

View attachment 228778

I did not know what I was doing when I built this plane. I can see a lot of mistakes that hopefully can be fixed. The fuselage is in decent condition aside from some crooked formers that 12-year old me installed and some cracked sheeting. The vertical stabilizer obviously needs to be fixed or rebuilt. I still have the plans, which are in very good condition given their age and the fact that back then I wasn't all that good about not glueing planes to them, so I can fabricate any new parts I need. The horizontal stabilizer looks to be in perfect working order.

The wing is a little more beat up but still salvageable, I think. You can't really tell from looking at it, but both outer panels have partially broken loose. This is probably the worst spot:

View attachment 228779


Something thought my plane tasted good:

View attachment 228780

I'm going to assume that was done by our dog or cats and not some random ravenous rodent that found its way into my storage space.

I'll post more pictures once I remove the covering and do a full inventory of the damage.

I may convert the outer wing panels to be removable per the plans. I need to do a test fit with my car, which is much smaller than the minivan I used to use to get to the flying field.

I want to make this plane a motor glider, but I like the look of the nose and don't want to remove it. Back in the day I built the over-wing power pod but never flew with it. I may experiment with an electric version of it.

I loved my Gentle Lady. It's well worth restoring.

 

[kkelly]

I removed all the covering. The damage is worse than I expected, but still repairable. Both outer wing panels have separated:

The fuselage needs some new sheeting on the top and near the tail. Since this picture was taken I've removed the horizontal stabilizer and started cleaning up its mounting platform.

A lot of the Monokote residue is coming off with some light sanding. It seems I didn't sand the model much (at all?) when I built it, so it needs sanding anyway. The more stubborn spots have to be picked off with a razor blade. The areas where it's just a little dye stuck to the wood clean up with alcohol. I tried acetone like someone recommended on another site, but it made the dye soak deeper into the wood.

I'm reconsidering the removable outer wing panels after reading a post by @speedbirdted in another thread. I think the wing will fit in my car with a little finagling, and I would be so paranoid about it coming apart in flight that I would probably weigh it down with so much tape that it wouldn't fly.

The nose block came off when I removed the covering, and it turns out I didn't shape it very well the first time around and the covering was hiding some sins. Since I'd have to make a new one anyway I'm leaning towards a permanent motor glider conversion instead of the power pod now, especially after seeing how well it turned out for some other builders. With a shortened block and a good folding prop they made the nose look great.

 

[Tench745]

If you're thinking of doing an electric conversion, do yourself a favor and look up plans for the Electra, it's the powered version of the Gentle Lady. It'll give you a sense of how much down and right-thrust is recommended.

https://outerzone.co.uk/plan_details.asp?ID=6614

 

[kkelly]

If you're thinking of doing an electric conversion, do yourself a favor and look up plans for the Electra, it's the powered version of the Gentle Lady. It'll give you a sense of how much down and right-thrust is recommended.

https://outerzone.co.uk/plan_details.asp?ID=6614

Good point.

 

[kkelly]

Well this was unexpected:

I have no idea why I placed those ribs so far off. The wingtip that's still attached lines up with the plans. I'm tempted to try to separate the glue joints and align everything properly, but will it make a significant difference to how it flies?

 

[tamuct01]

It looks like the leading edge has "racked" to the left or right pulling the ribs with it. I don't think you'll get it back aligned without a serious headache. It likely won't affect the flight characteristics. I'd be more worried about twisting or bending of the wing that might affect how it flies.

 

[kkelly]

It looks like the leading edge has "racked" to the left or right pulling the ribs with it. I don't think you'll get it back aligned without a serious headache. It likely won't affect the flight characteristics. I'd be more worried about twisting or bending of the wing that might affect how it flies.

Now that you point that out it makes perfect sense. The instructions say to not glue the outboard ribs to the spars until after joining the inner and outer wing panels. I probably left the leading edges too long and pushed them out during joining, then carved the wingtips to fit without realizing the misalignment. It's also possible I realized the error a little too late, panicked, and did the best I could to recover. Since it's probably not a flight issue I won't worry about it. I only ever flew this plane in short glides launched off a hill, but I don't recall it behaving oddly.

 

[kkelly]

I haven't had much time to work on the plane the last couple weeks, but I have made some progress. The vertical stabilizer and rudder are done aside from some sanding. The horizontal stabilizer was too far gone, so I had to build a new one:

I've spliced in new wood to replace the damaged parts of the wing, so next on the list is to reattach the outer panels. I can't find the recommended 1/16" plywood for the joiners at any stores around here, and to order it would cost $15 in shipping fees for a single sheet, so I'm going to use some 1/8" ply I already have on hand.

I originally hinged the control surfaces using the covering film per the instructions. I'm going to use proper hinges this time. I have both CA and nylon hinges. Would either be a better choice over the other for this plane? I'm thinking 7 hinges on the elevator and four on the rudder. Is that overkill?

 

[Piotrsko]

I have some Dubro pin center hinges that are 45 years old on one of my planes, along with covering hinges, fed ex baggie tyvec hinges. The covering hinges are age suspect because the rest if the covering has gone brittle. On a 4ft span wing I use 3 per side and toothpick pin them in place

 

[vhandon]

I prefer nylon over CA but either will work on this plane. I think 7 hinges on the elevator is overkill.

 

[kkelly]

It's been slow going on the restoration while I worked on some other projects, but I'm getting back to it. The wing is fully reassembled. There is a lot of wood that has Monokote residue stuck to it such as this:

The only way I've been able to remove it is with sanding, but I'm worried about taking off too much wood along the way. I've already tried alcohol and acetone without success. Are there any other methods I could try?

 

[Piotrsko]

The wood isn't so much a load bearing thing but more of a stiffener and a place to attach covering to. You can go as thin as 1/32 (typically 1/2 thickness) before you have strength issues (which tend to be fat fingers punching through it)

Have you tried heating the gunk with an iron or heat gun to soften it enough to scrape it off?

Otoh, once it's covered, you'd never see the ugly from Bakersfield.

 

[kkelly]

Have you tried heating the gunk with an iron or heat gun to soften it enough to scrape it off?

Otoh, once it's covered, you'd never see the ugly from Bakersfield.

I used a heat gun when removing the old covering film. It appeared to be deteriorating and in many places the colored layer separated from the top film. The residue looks like it's down in the wood and not sitting on top of it, so I don't know if scraping will be effective. I'll try it to be sure. As far as not being visible through the new covering, would that be true even for a transparent film?

Speaking of load bearing parts, I've read accounts of some Gentle Ladies having strength issues. As long as it's all apart are there any reinforcements I should make?

 

[Piotrsko]

Been my experiences: on some light colors the stains will show with transparent. Blue, red green, purple, probably not. OTOH, I only used transparents for places where I wanted to see through, the planking and solids were always solid colors. A quick coat of krylon almond hides everything.

My experience with gentle ladies is back from the original kits of the '70s where they tended to wing flutter and fold the wings during winch launch. They got noticeably improved but kinda disappeared with the introduction of Bird of Time. Hobby shack had them into the 90's since they were supposed to be a trainer for thermal use.

What will you use it for?, and remember NEVER pull up on launch tow.

 

[kkelly]

My experience with gentle ladies is back from the original kits of the '70s where they tended to wing flutter and fold the wings during winch launch. They got noticeably improved but kinda disappeared with the introduction of Bird of Time. Hobby shack had them into the 90's since they were supposed to be a trainer for thermal use.

What will you use it for?, and remember NEVER pull up on launch tow.

Mine is from 1989 or 1990. The main spar is bass. I think the earlier models had a balsa spar. I plan to convert it to a motor glider. I won't be launching it with a winch or anything else that will put a lot of stress on the airframe.

 

[danskis]

Motors probably put less stress on the frame than a bungee launch. The last motor glider I built I didn’t use the entire top sheet that goes from the wing to the tail and it’s fine. I don’t think you can sand too much wood off of it. I haven’t built one but I’ve owned one. It’s way overbuilt.

 

[danskis]

When you get it back in the air do a dive test to see if you can improve your CG position. Just Google glider dive test.
And a folding prop will improve performance by 50 to 100 percent

 

[FlyingTyger]

It's been slow going on the restoration while I worked on some other projects, but I'm getting back to it. The wing is fully reassembled. There is a lot of wood that has Monokote residue stuck to it such as this:
The only way I've been able to remove it is with sanding, but I'm worried about taking off too much wood along the way. I've already tried alcohol and acetone without success. Are there any other methods I could try?

I remember reading about a trick to remove this gunk. You lay something like paper towel or a blank sheet of paper over it then heat it with an iron. The residue will stick better to the paper than the wood and will peel off with the paper. I haven't tried it myself yet, but it might be worth giving it a shot.

 

[kkelly]

I remember reading about a trick to remove this gunk. You lay something like paper towel or a blank sheet of paper over it then heat it with an iron. The residue will stick better to the paper than the wood and will peel off with the paper. I haven't tried it myself yet, but it might be worth giving it a shot.

That sounds vaguely familiar. I'll give it a try.