flightprep

Carpenter glue is a much less sensitizing (allergy initiating) than epoxy as well. Unfortunately it's not fuelproof like epoxy. Brgds Flightprep

mred33

True, but I cover over the engine compartment and fuel tank area with finishing epoxy to fuelproof the area. I normally put 2 coats in the engine bay and 1 coat in the tank area. I've never had a problem with fuel soaking in either of these areas and it's easy to clean up after you fly.

slim_pkns

I went out and bought some quick-release adjustable clamps/spreaders from the hardware store. I think I'm going to get everything from now on from Harbor Freight. The have a great selection and price but I couldn't wait on a couple of these. I bought nice size bottle of Titebond II as well. I'd like to get that added bit of strength and if it's a bit easier to sand down, all the better! Thanks for the input guys.

Progress so far shown... got three stiffeners to add to both sides but haven't glued them in yet because I need to think about my next problem a bit first. The fuselage sides went together fairly easily except for gluing the outside wall pieces made of 1/16" balsa sheeting. The instructions (two sentences =) ) said to use masking tape to put two pieces together and then bend them apart to add the thin bead of glue. Lay down the sheet, masking tape down and wipe off any excess glue. Since I added the weight on top as I glued each part together as you both mentioned is critical... sure enough, I ended up with a nice straight as an arrow fuselage side.

slim_pkns

So, my next problem is this... now that I have this fantastic fuselage side with absolutely no warping, How the hell do I get the curve in the tail shown on the plans? I guess I'm going to have to use on of the water or ammonia soaking techniques I see people posting about here and there. I'm concerned about this because I'm using water soluble glue! Here are a couple of shots that give you an idea of my predicament. I'm hoping I'm tackling this at the right time. I'm wondering if I should have addressed this earlier but... build and learn, right? Not like I can go out and buy another VK Cherokee Babe kit though.

Any advice is SOOOO appreciated!

mred33

I would suggest that you cut the holes for the stab before you glue anything else together on the fuse. If you are talking about what I think you are talking about, all you need to do is bend the fuse sides around the formers while you clamp them up to dry and make sure everything is as square as you can make it before the glue dries. Bending the sides around the formers is easy and you shouldn't need anything on it to help you make it bend except for the clamps or rubberbands. I have never had a fuse that would not bend like this and if you need to put water on there that would be a first for me. Balsa bends a lot easier then you think. That is one reason why you need something to hold it down while you glue doublers on to keep if from bending and curling up on you . As for the water attacking the glue after it is hard, don't worry about that. What little water you would be using is not going to hurt the glue any for the short time it would be one there.

Ed

buzzard bait

Just for future reference, I would not glue the thick triangle stock on before bending, or at least not at the rear. Now that's it's glued on, see if it will bend - it probably will.

Of course, the first thing to do is get the formers in the forward section on absolutely square. Then when you bend the rear part, it will have to come out right if the ends of the fuse meet.

If it won't bend with the triangle stock, saw some notches in the places where it needs to bend, and then firm up with glue.

And yes, cut the stab slots while you can still line up the two sides perfectly together.

Jim

mred33

I've never had problems bending the fuse with tri stock in place. I am working on one right now that has tri stock top and bottom and it bent with no problems. I do glue the center formers first and let them set before I try and bend the tail together and I put the formers in as the sides come to them and I normally do one at a time until I get to the tail. Make sure everything is straight while you are bending everything and keep it lined up all the way through and it should come out nice and square.

Ed

slim_pkns

Thanks a lot guys! I read your posts and studied the plans and I think I have a good understanding of what I need to do. I'm glad I invested in some good clamps. I can see they will really come in handy for this next step. The instructions aren't in front of me (I'm at the office right now) but I recall that it said to install the formers and firewall forward and then alludes to (without actually stating it) working your way back towards the tail. I think I'll be able to gently squeeze the two sides together when it's time to glue the third former in where the curve starts and then close the tail at the tip. Playing around with the flex of the triangle stock and fuse side... it's really going to test the strength of this Titebond II.

More tonight and tomorrow!

mred33

I always us epoxy to glue the firewall in and Titebond for the rest of the formers. Glue the former in front of the wing and the other one in back of the wind and get everything lined up as good as you can and let this glue set good before you do any more. I go to the tail and get everything glued in and THEN do the firewall, but then that's just me. Getting this part right will go a long way to getting a true fuse and that is half of the game, so take your time and get it straight.

If the Titebond lets go, I think you will find that it pulled the balsa fibers that it was glued to along with it. That means that the glue is stronger then the wood, which is what you want. You don't want the glue itself letting go, you want the wood to let go. I have NEVER had a glue joint break, it was always the wood that went. Good luck with it and don't worry about the glue letting go, it won't.

Ed

qwerty3

Hmmm - anyone for Ambroid glue? (Just kidding - not even sure where you'd get that stuff). I've heard stories about Ambroid, but never used it.
Built some stuff with Titebond, though. In my experience, it did not work well for laminating type joints, because one or both of the pieces would warp due to the moisture. It is more forgiving of joint fit-up than CA, but a lot slower. Building was a series of 'set up a joint, glue and pin', then wait until the next day, repeat. In this 'instant gratification' society, maybe that's a good thing to have, these days?
Never built a Cherokee Babe, but got ahold of a crashed one, rebuilt it, and flew it for a while, with a worn-out ST40. It flew pretty well, but the main thing I recall is that the wing loading was pretty high - I had to land it like a jet airliner - a little throttle added *just* before touching down - otherwise it came down too hard, and bounced, no matter how carefully flared. Adding some wing tip extensions made a noticeable improvement (until they got knocked off).
It could be that the plane I got was already heavy - it had been flown by the previous owner for many years. I'm not sure how carefully it was originally built (i.e. over use of epoxy, etc.) For a new build, I recommend extending the wings another rib on each side - a little more wing area would improve it, IMHO.
On the other hand, a plane with that level of wing loading would probably benefit quite a bit by adding flaps for landing

mred33

Ambriod was THE glue to use when I first started. You had to double glue all your joints with that stuff and it helped to thin it out a little first. Some NUTS started putting a plastic bag over their head and filling the bag with fumes from that glue and that more or less killed the glue, along with a few of the idiots that tried this little stunt.

The babe builds great IF you don't get carried away with the epoxy and get it fuel soaked. Mine would glide in great and I never had a problem with it plowing into the tarmac on landing. In fact, it floated in rather nicely. Just have to take your time and build it light. By that I mean, don't use a ton of glue.

Using Titebond for glueing the fuse doublers is no problem and I get nice straight sides using this glue. Just take a board that is slightly bigger all around then the parts you are glueing together and put this over the parts while the glue dries. Make sure you add some weight to it to help hold it down and you won't have any problems with the sides curling up or warping the fuse sides. Let it set overnight and you will have some nice strong sides and STRAIGHT. Also, put some waxpaper under the sides and on top so you don't glue it to the wrong thing. It's not good glueing your fuse sides to the building table or the hunk of wood that you put on top of it.

When I make a normal glue joint, like installing a former, give it about 45 min and you can handle it again. Waiting overnight is nice, but not necessary. The only time I let things set overnight is glueing doublers. Then it takes a little longer to dry because the water has to evaporate through the wood and that takes a little longer.

Ed

slim_pkns

I've been caught up in the lawn, housework, and having a social life since my last post. I made progress tonight and thought I'd post a couple of pics. I'm in uncharted territory here so I hope to get a few comments. The instruction paragraph for the fuselage doesn't go into any detail after putting the fuselage doubles together. It mentions that I should epoxy the firewall rather than use wood glue. I used the same technique as the Guillow's kit I recently put together to continue with the fuselage. I added a few formers. Fitted them as best I could after pinning one side down on the plan and gluing them in while using an angle to make sure it was 90 degrees off the building surface and fuselage sidewall. I'm working my way back from the firewall since the curve I discussed in previous posts starts at the back of the 3rd former. I should be able to glue the three in shown in the pics and then add the other fuselage side before starting to pinch in the sides with the clamps to get the back end to tapper.

Hope I've got this right!

slim_pkns

HELP!!! I'm really having a hard time getting the formers and curve right in this fuselage. I spent a bunch of money on clamps and they just aren't what I need. I added the other half of the fuselage side with the firewall and two fuselage formers. I'm at the one where the curve needs to be right to get it glued in. The problem is that as I squeeze the sides together, one sides top triangle stock is much more stiff than the other and the one that is softer always flexes too much. I've tried playing with it using rubber bands, the clamps I bought, and just using my hands. I just can't get the right shape. Even if I did, at this point I wouldn't be able to get the glue on the former and get it in. I need six sets of arms! AAARRRGGHH!!! There's got to be a technique I don't know about. The warp would be TERRIBLE if I was to continue.

mred33

OK, first of all, DON'T glue the formers on one half and then try to bring the other half to it. The formers will be cocked at an angle that way. Bend the fuse sides alone and when you get to a former, install the former at that junction and clamp it. That way, the formers will be straight. Now if the sides are not bending the same because you put two different triangles in that are not the same stiffness, you have a choice. You can either cut the one out and replace it, or you can cut some notches in it to help it bend better. One thing you almost always have to do is replace some of the wood in the kits because some are stiffer then you need.

I don't think you want to go through the pain of cutting that stock out, so just cut some slits in it with an X-acto saw. You do have one, don't you???? That will help it bend easier and you can fill the cuts with glue after you get everything bent into shape. Bend to the first former you come to and glue that one in, and then clamp it. Bend again to the next former and clamp that one. Continue on until you get to the tail. When you clamp that together, make sure you have it straight and bent right and everything is lined up and then clamp it up and let it sit. Next time, check out he wood you are using and if anything does not look right, replace it. I have replaced more wood in those kits then you would believe and just for this reason. Save the wood and you can use it on another build. Good luck and if you have any more questions fire away. If you don't understand what I am talking about, let me know and I'll try and explain it better.

Ed

P.S. Just cut slits in the tri stock with the razor saw, not the fuse. You can put as many slits in as you need to get the bend right and then fill them with glue later after you get everything bent and glued to together.

slim_pkns

COOL! Thanks Ed! I do have an X-Acto saw and I made a few cuts in the triangle stock as you suggested. It definitely bends easier. Unfortunately, I went at it pretty good and made four cuts and I probably only needed two but I was able to get the bend close enough on both sides to make me happy and comfortable with moving on. I'd say the bend is off by about an 1/8th of an inch in the middle of the bend but both sides are at the same depth over the plan where the former is positioned. I'll try to finish up the back end of the fuselage and take another couple of pictures after work tomorrow. The glue should be nice and dry by then.

Thanks again!

mred33

No problem with the number of cuts. It can always be filled in with glue after you get it right. Just make sure that you get it as straight as you can. The better you get it now the better off you will be when it comes time to put the tail on. Got it CLOSE and I mean as close as you can. If it takes a couple more cuts, no problem, but this is where you get the fuse to line up and straight so you can get the tail on right. Getting that tail as close as you can to being perfect is the most important thing you can do right now.

When you are ready, force some Titebond on the cuts and make sure they are glued REAL good. Use a toothpick to get it in there if you have to, but get that glue in there to fill the cracks and get a good solid glue joint. Try and fill the cut ALL the way and make sure it is straight while it dries. Good luck and hope everything comes out alright for you.

Ed

slim_pkns

I think it has turned out fine. There are some things I need to do before gluing the top and bottom sheeting on but I feel pretty good about how things are turning out tonight. The pictures show where the worst of my problem was. Tonight, I turned the fuselage upside down and pinned it to the plan to make sure I got the top curve as good as I could when gluing the tip of the tail together. I used the clamp and clothes pins as you can see to get everything to stay put. To make sure I had the bottom tip of the tail right (at the top since I pinned the fuse down upside down ), I used an angle to see that the outside of the fuselage side all the way down the tail was 90 deg. off the table. The plan calls for using scrap balsa stock to glue the two halves together at the tip. This was tough since the triangle stock and 3/16 sq. stringer glued to the two fuselage side walls need to be cut out.

mred33

It's looking good. That tri stock is always a pain to get cut right and get the tail together right. In all my years of building, I've never found an easy way to cut that stuff and have it come out perfect. I normally get it as close as I can and just glue it together. You never see that part anyway after everything is all together.

If you haven't gotten any yet, try and find some Finish-Cure epoxy at the local hobby shop to put in the engine compartment and fuel tank area. It's really thin epoxy and easy to brush on. I think it is 20 min set time, but don't just take regular epoxy and thin it out with alcohol. Epoxy sets by chemical reaction of the two parts, not evaporation. If you mix alcohol with it, it stays in there and turns to rubber or close to it and some of it may peel of and then you have a nice path for fuel to get in the balsa. Finish epoxy set nice like regular epoxy and it will never come off and it doesn't turn to rubber. You can also use it for things like putting the fiberglass on the wing center section. It goes through fiberglass like water and will take two LITE cotes to seal it good, but it will look great when you are done and if you do it right, will be lighter then regular epoxy used there.

Ed

squeakalong

My Feedback: (8)

Hi, slim.

Perhaps a suggestion you can use. Go to your local brick paver yard and pickup a few solid pavers; they come in what are called "twinkies", "cakes" and "pavers". Pick up 4 "twinkies" and a couple of "cakes". These bricks are quite heavy and I use them when I am aligning a fuselage over the plan (top) view, I place these bricks on either side of the fuselage as I bring the tail together over the centerline. Place one on each side at the cowl (engine) area and one on each side of the fuselage just in front of where the fuselage starts to bend together (usually at the point where the rear of the wing will mount). This will keep your work in place as you work on the area rearward of the tail and help to avoid a twist in the fuselage. Hope this helps.

Soft landings.

slim_pkns

Thanks for the finish-cure epoxy tip Ed. I'll look for it when I take my next trip to the hobby shop. I took off a little bit early from work today thinking that I would come home and finish up the fuselage by gluing the top and bottom sheeting on. Fortunately, I made myself a Crown Royal and water to relax and look things over before getting started. I realized the formers at the back of the fuse are solid and there's no mention of drilling holes for the push rods! Thank God I thought about it! I would never have been able to get to the B3 former if I had glued the top and bottom sheeting on. I went back and looked at the photos flightprep posted of his rebuild to get an idea of where best to drill holes. You can see in posts #41 and #42 that the original builder of that model cut a huge amount of space out of the middle of both B2 and B3 formers. B3 has a doubler on top and bottom so I feel a little better about cutting away a larger hole in the middle but B2 isn't very thick and seems stressed after bending the fuse sides toward the tail. I'd rather drill smaller holes if possible. I'm considering stopping the fuselage build until I go to the hobby shop and buy push rods and possibly that push rod tubing or guide... I don't remember what it's called. I need rods longer than 24" since it's just about that distance in a straight line from where the servos are shown on the plans and the control horns and there needs to be bends as the rudder and elevator rods exit the fuselage. This is the first time I've ever had to design the install push rods myself since I've only pieced ARF's together in the past and everything is pretty much done for you.

slim_pkns

Good idea sqeakalong... and I love twinkies and cake! I'll check that out.

squeakalong

My Feedback: (8)

I'd never heard the bricks referred to in that way prior to having our brick patio put down this summer. I kept hearing the two guys talking about "twinkies" and "cakes" as they were laying out the patio. Thinking they both must have one 'ell of a sweet tooth I offfered to go get some snacks. Then they both looked at each other and started to laugh as they told me that's how they call out the particular brick size they want for a particular location! To hear them at work you'd swear they were in a bakery!! I swapped out the paver style bricks for the regular bricks I had been using and find the pavers work better (lots of mass in a small area). Good luck on your build!

Soft landings.

mred33

It's a good thing you saw that. It's REALLY hard to get those pushrods in there with the top and bottom on. I always leave the bottom off until I get the pushrods in. If you happen to have the 90deg attachment for the Dremel tool, it makes it easy to drill a hole in the former for the pushrods. It comes in handy for a lot of things while building. If you can afford one, pick one up, you'll be surprised at how handy it is. If not, a 12" long drill bit will work wonders.

One thing I like to use for pushrods is the Sullivan black pushrods. The outer section is black and it is stiff. If you don't have much in the way of bends in there they work great. They don't change length any where near as much as some of them. If you have some bends, get the red one. That one will bend a little better. Also, if you don't have your servos installed yet, it's best to install them and get the pushrods lined up where they are supposed to go and get them glued in so they are the right length and in the right position and are not flopping around getting in your way all the time. If you need to, you can take the servos out again after you get the pushrods right. The Sullivan pushrods come with the stuff you need to make the ends, so you don't have to worry about buying that extra. Use a drill to run the threaded part into the center section and it goes in great. Th elong peice is for the back and the short one is for the servo end.

Also, if they go through a former with a big hole in it, put a couple of balsa pieces at the top and bottom of the pushrods and glue them to help keep them in place. The more support you have for the pushrods the better. You can just use some scrap to make these pieces. Make sure that any place you add glue to the outer section of the pushrods to sand it first so that it is nice and rough. If you don't, epoxy won't even stick to it and they will break loose.

Your build is looking great so far. Keep up the good work.

Ed

slim_pkns

Quick update... I've been trying to finish my Guillow's Piper Super Cub so I haven't made much progress on the VK Cherokee Babe. I have the parts I need to get the pushrods installed and make a servo tray. I'll try to get that done in the next week and post photos.

slim_pkns

I recently finished my Guillow's Piper Super Cub and although I was less than successful with the electric conversion for indoor flight, I learned a lot.

I'm back on my Cherokee Babe build and even had another person ask for a copy of the plans. I'm always amazed to read about the number of people who want kits and plans for models that are discontinued. You'd think they could keep a company in business.

Anyway, I'm back on this build and will post another update with pics later.