BMatthews's blog View Details
Posted by BMatthews | Mar 06, 2019 @ 03:58 PM | 31,582 Views
I posted this in a thread but it's something worth putting here for posterity too. Hope it helps some of you.

ut in a flat line and wanted badly to actually dive into the work. It SEEMED like a good idea but was a total disaster.

On the other hand by far the most typical factory sharpening is the hard beveled shape shown in "B". I tried to show why this isn't a good detail carving shape in the second part of the sketch below showing how the hard heel will lever up the actual cutting edge. This makes it tough to maintain a nice flowing cut and doubly difficult to make a neatly curved hollowed cut.

The sweet spot is the apple seed shape where the part of the bevel that we use to guide the cut is immediately behind the cutting edge and the rest flows smoothly up and out of the way. This makes our lives easier when it comes to carving shapes and nice details.

Did some reading and learned about the better and more durable "apple seed" shape. But even there we walk a fine line between too blunt and edge to work well in soft balsa and too sharp which tries to act too much like "A" and wedge itself deeper too easily. Then there's the compromise of a finer angle which proves to be less durable and going too blunt and having a durable edge but one that needs too extreme an angle to the surface before the cutting edge ingages and a shaving comes up. Basically Papa Bear's knife, Momma Bear's knife and Baby Bear's knife....

I went down and...Continue Reading
Posted by BMatthews | Aug 07, 2018 @ 09:42 PM | 39,729 Views
Continuing in the light duty free flight fun theme so far this thread will be to present a series of smaller all sheet "Garden Gliders".

Why you ask... someone?... .Anyone? I'll tell you anyway.... As a youth building my first models small gliders from 4 to 12 inch span that I could fly easily in my backyard were a great way for me to experiment with all sorts of layouts like flying wings, delta wings, "flying saucer" round wings and canards. Plus they were easily built from just a few cents worth of balsa. So I've always had a soft spot in my head... er... HEART for small gliders that are easy to make and fly up a real storm.

The first is one that I drew up some time back but it fits in here as you'll see. It's the Backyard Jet which is now alternately to be known as the Garden Glider #1.
Posted by BMatthews | Jul 24, 2018 @ 12:37 PM | 40,076 Views
Plans for a basic but fairly easily built Catapult Handlaunch Glider.

The catapult for this model would be a 9 to 10" loop of 3/16 flat rubber model strip rubber. If you don't have that I'd suggest a "daisy chain" of four #32 rubber bands linked together to form a single long rubber motor. The other end should be a 5 to 6" stick so you don't loose the rubber or allow it to snap out of your grip and fly back at the model.
Posted by BMatthews | Jul 24, 2018 @ 12:32 PM | 40,872 Views
Building and Trimming Free Flight Hand and Catapult Launched Gliders

The flight trimming for hand launch FF gliders starts on the building board.

If you're right handed you want the model to circle to the left in the glide. To achieve that with only adjustments to the fin means that there will be much too much turn in the launch. To get around this it's normal to use some stabilizer tilt to provide some left turn. This means you want the left side stab tip to be about 1/4 inch high compared to the center line. Reverse everything if you're left handed and will be going for right hand circles.

To aid in smoother recoveries from stalls you want a little bit of washin on the left hand wing tip. I used to warp some into the wood but now I "toe in" the outer dihedral break on the left side by 3/32 inch over a 4 inch chord. Tapered wings with smaller chords at the tip break would be angled appropriately less. I know this sounds odd since the washin at the tip is fighting the rudder. But trust me. Having the model set up so the turn fights the washin is what aids in avoiding those frustrating never ending series of stalls that never seem to damp out. Models set up with a touch of washout will settle back down a lot nicer and with a more rearward CG than "straight" models. If the wings are simple V dihedral then make the center line joint skew to the right at the leading edge by 1/16 inch over 4 inches of chord, or some scaled down amount...Continue Reading
Posted by BMatthews | Jul 24, 2018 @ 12:30 PM | 38,825 Views
So I've been around RCG for more than 10 years now and never saw much use for a blog. But I find I post the same things at multiple times. So perhaps this is a good place to put them so others can find and hopefully find the information useful.

The long term plan is to fill my blog with plans for tools and some simple plans for models and give my own take on some techniques. The focus will be rather biased towards free flight in some ways. But the writeups on tools and techniques will be purely general and shop related.

I'll edit this first post to act as a "Table of Contents" to help with finding items more quickly.

Post- Topic
2 - Building and Trimming free flight Hand and Catapult launched gliders.
3 - Camp Cookout CLG plan