The Scratch Plane featured in Fly Rc
 

May 2008 issue #54 . Is anyone planning on building this little plane? Several in my club are planning to start at least 6 next monday. If you have built this plane please post your results and any mods you may have made. This is going to be most of us first build like this and need some advice.

RE: The Scratch Plane featured in Fly Rc
 

You might want to post which design it is and the month of the magazine. Fly RC has full size plans on a regular basis and no one will know which you are reffering to in a few weeks. I seldom see the magazine so I don't know either.

RE: The Scratch Plane featured in Fly Rc
 

Good idea Bruce I edited my first post to add the Issue info . A club member who has been doing this for along time and who is going to be guiding us in the ways of the plane building force, came up with a bill of materials. Looks like it going to come togeather

RE: The Scratch Plane featured in Fly Rc
 

I'm planning on building my own "Scratch". I just got the plans enlarged today, and I'm going to get the wood this weekend.

This will be my first scratch build. I've studied the plans, and I don't see anything particularly difficult. This seems like a good plane to start with. I'm thinking it would be nice to have a build thread here for collaboration.

RE: The Scratch Plane featured in Fly Rc
 

Oh great... now I need to go check out the newstand. The FlyRC website is still showing the current issue as April.

All I can say is that this better be good.... :D

RE: The Scratch Plane featured in Fly Rc
 

RSteffen, Thats a great idea I will post our clubs progress with pics. We are not slated to start till Monday, March 31. We are already planning a few mods to the plane. Such as no daheadrial and 1 servo in each wing half. The latter is a great way to learn how to set up flapperons for different types of flying. Please post your progress as well.

RE: The Scratch Plane featured in Fly Rc
 

Bruce I just got mine the other day. Its a simple plane that will teach basic tecniques.

RE: The Scratch Plane featured in Fly Rc
 

I too am planing on build the Scratch as my first airplane. 25 years ago I got close to finishing a balsa/ply sailplane but moved away to college and never came back to it. 3 months ago I purchased a simulator, which I flew 2 hours a day for two weeks before flying the Parkzone T28 that I also bought, which I can now fly fairly competently.
Anyway, I would really appreciate any tips, and photos that you folks can share as you go through the build process. I will start in a couple of weeks once I have cleared out my garage and finished installing a whole house fan in the attic!

RE: The Scratch Plane featured in Fly Rc
 

Jg, As soon as I can I will post pics. Next Monday is when we plan to start the wing. I have a bill of materials list that we made up. It should get you very close to a completed plane. We decided to built this plane in order to teach some of us new comers techniques that we can find helpful in modeling. There is more to it than just buying ARF's which is fine if you have alot of money. I plan on building 2 . 1 gas , 1 electric.

Sheet balsa
(6) 1/16x3x36" balsa
(1) 1/4x3x36" balsa
(2) 1/8x3x36" balsa
Stick balsa
(1) 1/4x 1/2x36" balsa
(2) 1/8x3/8x36" balsa
(2) 1/8x1/4x36" hard balsa
(1) 1/4x3/16x36" balsa
(1) 3/8x36 balsa triangle stock
(2) 1/4x1 1/4" aileron stock
Spruce stock
(1) 1/4x1/4x36" spruce stock
(3) 1/8x1/8x36" spruce stock
(1) 3/16x36 dowel
Plywood
1/8x4x6" liteply
(1) Sheet 1/64 ply
(3) sheets 3/32 ply
Hardware
(1) 8-32 nylon bolt
(4) Dubro 1/2a control horns
1 pack EZ hinges
Tools and glue
(1) 1/4" foam core poster board (can be found and Hobby Lobby or Office Max)
Xacto knife and # 11 blades
Good quality 3' metal yardstick
(1) bottle thin ca super glue
30 min epoxy.

RE: The Scratch Plane featured in Fly Rc
 

lrglnman, I really appreciate the bill of materials. I had a stressful day and decided to stop by the LHS tonight and got a real kick out of looking at the balsa sheets, finding the airleron control kit, looking at the monokote.

Is the poster board for creating templates??

I was also looking at the Spektrum 6i radio. Currently the only radio I have is the one that came with my Parkzone T28, so I need something new. Any input on whether this would a be good choice for a good radio system for me, for the next couple of years.

RE: The Scratch Plane featured in Fly Rc
 

Jg, no the foamcore poster board is for laying on the table . then you lay the plans over that so you can pin the wood down on the plans. you can use an old celing tile as well. just something flat that you can push t pins in . As for radios go, I would look at nothing less than a 7 channel. If you ase sure that you are going to be in this for a good while get at least a 7 channel. that way when you are ready you have the option for a lot more mixes that you can do.

RE: The Scratch Plane featured in Fly Rc
 

thanks for the feedback on the radio. It is hard to imagine using 7 channels but I definitely expect to stay with this hobby so I will go with what you say. Is 2.4ghz the way to go?

How did you go about getting the plans enlarged? I am thinking of just taking it to Kinkos and getting at least 2 copies, one to cut up to make templates. Does this make sense?

RE: The Scratch Plane featured in Fly Rc
 

I'm from a simpler school of thought in many ways. 7 channels is nice if you ever expect to fly camber altering sailplanes or similar designs where you need a separate channel for every surface rather than one per control. But if you don't expect to need that any time soon then a 4 or 5 channels is fine. But the all singing/all dancing 7 channel rigs DO come with lots of nice model memory and mixing options so that can often be worth the extra cost.

I recently got my first 2.4 set and I won't be going back. The freedom from worry about being shot down or accidentally shooting someone else down is well worth the price. It IS the way of the future. I'll continue to use my old sets for the time being but as they fail or get sold off all my new ones will be 2.4.

Kinkos or similar would be fine. If you're lucky enough to have a copier at work that handles 11x17 that's another option. Or even just with legal size. Keep in mind that you don't need to blow up the entire plan. An edge joined tiled strip with the wings and another for the fuselage will keep the seams and alignment issues to a minimum. From there just spot copy/enlarge for the specific parts and tail surfaces. There's no need at all to tile enlarge the whole plan.

RE: The Scratch Plane featured in Fly Rc
 

JG, Bruce has a good point on the radios. However if you want to do mixing, which I find extreamly useful, then 7 channels or mor is better. Alot of your planes in the ARF lines are comming out with 2 servos on the wings. I find this fantastic because I can turn the ailerons into flaps and mix a bit of elevator so my landings are super smooth I can program this to any switch on the radio I want to. each servo has its on channel.I have no experience with 2.4 but as Bruce stasted it is the future of radios. I will wear out my Futaba 7 cap first then get the 2.4 . As for the plans , here in my town their is some folks that have a CAD business which does drawings for buildings or an computer aided drawing. They inlarged my plans 250% which is to scale for $ 4.50 a copy. super cheep I think. I think Kinkos or ofice max will do it as well. Or look in your local phone book for CAD services they will be able to do it for sure.

RE: The Scratch Plane featured in Fly Rc
 

I agree with the 2.4 and extra channels and features.

But the 2.4 receivers are too large for small scale foam. [&o]

INDOOR FLYING
I would like to hear that my 2.4 transmitter could support small CD-ROM motor driven foamies.

My new 2.4 has room for storing multiable setups <hum?>

And the 2.4 receivers are not cheapies either.

RE: The Scratch Plane featured in Fly Rc
 

Since the thread kind of wandered a bit, I thought I post some pics of the progress I've made on mine. One wing basically constructed, the second one about halfway done.

RE: The Scratch Plane featured in Fly Rc
 

It looks like you are making good progress. I have basic questions because I haven't built anything from balsa in 30 years.

I have cut out and sanded the 1/16 ribs and they look ok. It was harder work cutting these out than I expected. I think I need to get a larger xacto knife - maybe I am just getting weak in my old age! So I am now wondering how best to cut the 1/4 ribs??

Also, looking at the fuselage the ply doubler has nice circular cut outs - how do you go about cutting those.

Are you pinning the wing directly to the plans or do you have plastic or something in between? Dare I ask what the syringe is for?

What glue are you using and do you use CA activator?

RE: The Scratch Plane featured in Fly Rc
 

Well, I'm learning as I go along. Cutting the 1/4" ribs wasn't as hard as I thought it was going to be. The trick is that the grain of the wood is going from leading edge to trailing edge on the rib, so your longest cuts are going with the grain, so a knife blade only has to split the grain. I just used a fresh #11 XActo blade, and made the cut larger than my template (I made a rib template out of 1/8" lite-ply and used it to cut out all of the ribs). Then I just sanded the ribs down to match the template.

Looking at the fuselage plan, I see circular holes in the bottom sheet, which is 1/16" balsa. Shouldn't be hard to cut those with a sharp knife. And, in the sides I see rectangular holes with rounded corners in the ply doubler. However, the plan says that doubler is 1/64" ply, which is very thin and seems like it should be an easy cut with a good knife and a straightedge.

My building surface is a Great Planes 36" building board. The plans are pinned to the board, and a layer of Great Planes plan protector is pinned on top of the plans. In retrospect, the plan protector is nice but wax paper or plastic wrap would do the job pretty well, too.

For glue, I'm using Titebond (Aliphatic Resin), which is what is in the syringe. The syringe is a "drywall syringe" from the hardware store. I have no idea what you'd use it for with drywall, but it seems tailor made for this job.

I have used a bit of medium CA on the first wing. Got a little over enthusiastic while sanding the trailing edge spar and cracked two ribs - fixed with medium CA.

RE: The Scratch Plane featured in Fly Rc
 

Thanks for the feedback. I will pick up some more xacto blades on the way home tonight and see if I can get the 1/4 inch ribs cut out. I too made a rib template out of ply and epoxied two small brass tubes following what the author showed in his picture - this allowed me to essentially punch holes in the ribs - this actually worked well because it held the balsa in place while I cut around the ribs.

Is there a reason you are using Titebond rather than CA? Which type of Titebond are you using - I was looking at it in the store and there are several kinds.

RE: The Scratch Plane featured in Fly Rc
 

I got 1 wing built monday nite. Dont forget to allow for your servo wires if you use 2 servos in the wings. I did not put any diheadril in mine and built one wing. We will have another build next monday and I hope to get some pics then. I used thin ca only in my wing build. get you some of those ca applicators to put on the tip of the ca bottle .that way you place the ca just right. there is nothing wrong with tightbond. its the best a/r glue on the market. use wax paper to protect the plans. if you sand a rib a tad bit too much and you need t stretch it you can sprinkel some bakeing soda in the crack and hit it with thin ca. crack gone and a pretty good fix. pain to sand though. I will build my next wing with diheadrial in it.

RE: The Scratch Plane featured in Fly Rc
 

I'm using Titebond over CA for 2 reasons - longer working time (plenty of time to get things aligned), and sandability. There a trade off in build time though, it's a bit slower to build this way.

As for which formula, I'm using the original Titebond, mostly because that's what I had on hand. I spend a fair amount of time reading build threads in the Kit building forum and here and most people seemed to recommend Titebond or Titebond II, and honestly I don't really see a huge difference between the two. Titebond III's major feature is water resistance, which I didn't think very important for this.

RE: The Scratch Plane featured in Fly Rc
 

Thanks for the feedback on glues. I was concerned I would get the hole thing built and then find out I had used the wrong glue! However, with my current flying skills it wont be long before I am building a second version! I think I am going to use a combination of Titebond where I need the additional time to move stuff around and CA with activator where it is easier to lock stuff in place immediately.

As an experiment last night I used some Elmers carpenter glue on a couple of scraps of balsa - it dried in under an hour and seems very strong. All the modern glues seem to be so much better than the crap that was around when I was a kid. I did some renovation work on a sailboat a few years ago and was amazed at the strength of epoxy.

Last night I finished up the wing ribs - using a larger xacto knife with a more comfortable handle made a huge difference - the 1/4 ribs came out easily.

I took a few photos last night which I will post soon

RE: The Scratch Plane featured in Fly Rc
 

jg if you use thin ca you won't need to use activator as it sets almost instantly. I and all my club buddies used thin ca entirely on the wing. fantastic results.

RE: The Scratch Plane featured in Fly Rc
 

Here are some pics of the first wing. I am now half way through building the second wing which is going much faster. The thin CA seems to work well - it certainly glues my fingers to the balsa very effectively!

RE: The Scratch Plane featured in Fly Rc
 

fantastic looks as good as mine!!:D