When I visited family in Holland in October 2023, I visited Ton van Munsteren. He is a prolific designer and has many models published in British model magazines. The best way to describe him is to call him Holland's Laddie Mikulasko*.
Ton had just designed and built the Box Fly 20 and gave me a kit. I had to cut the pieces to fit them into my suitcase.
The first step was to re-glue all the cut pieces. I pinned one piece to the board and aligned the other half by using a steel edge to make it straight.
Will let them cure overnight before starting to assemble the plane.
Photos:
1) photo of my visit to Ton's house and shop. The plane is in the foreground.
2) the kit as given to me
3) all the pieces were nicely laser cut.
4) the pieces I had cut apart were glued together. Note the metal ruler used to make sure the pieces were straight.
Frank
* Laddie flies with the Burlington group and has many designs published in RCM magazine. He designed the Force 1, Laker, Northstar and Easy 100 put out by Balsa USA.
Looks like a fun kit to build.
Make sure you do not end up with 2 right sides as the picture indicates. :D
Yes, Guy.
Before I started building it I flipped one fuse side over.
Sounds like you speak from experience.... but so do I! 8)
This is not a kit. It is a 3D puzzle. Formers are marked on the plans and the formers have laser numbering (F1- F11) but the numbers do not match the plans. The laser cutting is so precise they only fit one way.
Frank
ps: I had to line them up that way to join them because the steel ruler had to be on the bottom of each piece. Otherwise I could not have fit all the pieces on the board in one sitting..
starting to assemble the fuse.
F.
- basic fuse build finished. The motor is 450 watts for a plane requiring 400 watts. Just about right.
- tail feathers glued. Just need to be sanded.
- wing building finished on one side. Note the 1/4" square balsa near the trailing edge (at the point of the knife). This is a symmetrical wing shape. By placing this 1/4" square on an angle, I am building in "wash-out". (trailing edge at the tip higher than the leading edge for stall protection).
- the hatch is finished. Magnetic hold-downs still have to be added.
Next: the other wing half. It will be built onto this finished half.
Frank
- Building the second wing half- onto the finished first half.
- adding the shear webs
- cut out the canopy and build the headrest out of 8 pieces laminated.
Frank
Why is the headrest have white lines in the picture #5311?
Are these for alignment?
Quote from: GuyOReilly on April 09, 2024, 10:42:21 PMWhy is the headrest have white lines in the picture #5311?
Are these for alignment?
The dark parts are where the wood was laser cut (burnt), and the white (balsa wood colour) is where the wood was still attached to the sheet.
Thank you Michael! ;D
Frank
Guy, I decided to arc the headrest area to match the cockpit cut-out. It cradles the pilot's head during high speed turns. A built-in HANS* device. 8)
* https://flowracers.com/blog/how-nascar-hans-device-works/
Back to this project since my last post April 10.
Background
- the design is a Boxfly 20 adaptation by a Dutch friend of mine who publishes his designs in RCM&E magazine and has his kits laser cut by RBC kits.
- I gave him a box of small IC motors (.049's, .020's) and he gave me this kit to try out. We both won on this trade.
- most of the frame was built, motor installed before the hiatus when flying got in the way.
Next steps: installing servos, sanding, fibreglass the center section, install the landing gear, covering.
Frank
Fibreglassing the wing centre section:
Materials:
- 3/4 oz cloth
- 5,20, or regular epoxy.
- a 2" wide brush
- de-natured (isopropyl) alcohol- available at drug stores. Photo 15 shows the Rexall brand.
step 1- order- bottom first, overlapping the top by at least an inch. Top second, overlapping the bottom by an inch- this way the leading and trailing edges have 2 layers. These areas get the most abuse. I did one side at a time, letting one cure before doing the second half.
step 2- lay the cloth over the area to be re-enforced. The green tape in the photo covers the aileron plugs. Photo 11
step 3- mix the epoxy parts A&B completely. Slowly mix in the alcohol until it is about an equal amount epoxy and alcohol. The consistency should be that of water. Photo 15
step 4- apply the epoxy with the brush starting at the centre. Photo 13. Stab the epoxy onto the glass cloth. Brushing it slips the cloth all over the place. Once the centre is soaked with epoxy you can radiate the epoxy by brushing outward. Do not use much pressure at all. Brush until everything is soaked. Photo 14
step 5- let cure overnight. It may be sticky for a day or two.
Frank
... no stickiness the next day. Nice and smooth. No sanding required.
Frank
a quick and dirty way to line up a split elevator on a stabilizer.
It is always difficult to connect elevator halves when the centre has to go through the rudder. I hate the piano wire centre because you have to add a brass tube in the middle and find "neutral".
step 1- take the full elevator and mark the middle, add the hinges. This way everything lines up. Mark "up" on the elevator and the stab since this one is symmetrical.
step 2- add the hardwood dowel into the middle of the elevator. I cut out a slot and flattened the back of the dowel re-inforcement. The dowel was a bamboo skewer from the Dollar Store.
step 3- add fibreglass cloth and 5 minute epoxy and fold it over the bamboo skewer and flat out the back. This U-shape strengthens the middle. I put waxed paper over the fibreglass and put waxed paper over the fibreglass. The green tape is to put pressure on glass so there were no air bubbles. Photo 61 shows the full elevator with green tape. The photo also shows the semi-circular opening in the rudder.
step 4- cut the "V" shaped slot on the band saw for the rudder clearance. I cut out most of it but left some balsa about the same thickness as the bamboo skewer.
step 5- add a fibreglass strip to the "V" and roll the edge of the glass around the skewer so it is 100% covered in cloth. Photo 64.
Step 6- cover the cloth with waxed paper. I used the cut out portion of the "V" to put even pressure on the fibreglass. It is held in place by green tape while the epoxy cures.
Photo 66- finished. The bamboo skewer is visible.
A lot simpler than "U" shaped piano wire. Total time about 30 minutes and that included 2 mixes of 5 minute epoxy.
Frank
ARGHHH !!
Using a white and red covering scheme....because it was the covering I had*. Covered the 4 wing panels. Everything went fine until I shrunk the panels. One of them wrinkled, pulled and did not adhere to the main spar. The colour pulled off the back. See photo. Back into the covering inventory. Cut a new panel and ironed it in place. It seems to hold fine.
Frank
* I have an inventory of about 40 full and partial rolls of covering. I guess this one was old and dried... or it just did not like me. ;)
Final assembly....is next.
Photo shows everything is covered. The ailerons and elevator are hinged. The black tape is so the surfaces do not move while the glue is curing*.
The photo shows the fuse, wing and tail feathers, the cowl ring (white), hatch and headrest fairing (red).
Still have to figure out the landing gear. It is a tail dragger. There is a slot in the fuselage at the leading edge of the wing. Am going to try an Apprentice LG set sandwiched between two plates of plywood.
Hope to complete the final assembly tomorrow.
Frank
* my house is a CA free zone because of my wife's allergies (to CA glue, luckily not model airplanes ;) ). I use CA hinges but use wood glue to glue them in place. Works fine.
How I align the wing and tail feathers.
Approach:
Step 1: attach the wing to the fuse. Measure from each wingtip to the back of the fuse. Make sure both distances are equal. Mark the centre line.
- drill the wing for the bolt (I used two). Drilled into the fuse's ply plate and tapped it for two 12-24 nylon bolts.
- adjust the wing saddle until the fuse sits upright on the wing.
Step 2: slip the stab/elevator in place. Measure that it is in the centre (equal sized stab on either side of the fuse) and from the stab tips to a point in the centre of the fuse (I used the cockpit front panel). Remove the covering from the centre of the stab top and bottom (photo 162) so the glue joint is balsa to balsa and not Monokote. Note photo 163- I slipped a toothpick between the stab and fuse to align it with the wing. (eyeball measurement, green arrow photo 163)
Step 3: install the fin/rudder 90 degrees to the stab. I actually tape a right angle triangle to hold it while the glue dries.
Trick- when a fuse pinches into a point at the back, I slide the stab backwards in the slot about 1/4" (green arrow photo 161) and cut the covering with a sharp #11 blade on both sides of the fuse, top and bottom. This is so that when it is finally glued in, the fuse sides will completely cover the edge of the covering (top and bottom).
The fin/rudder happens tomorrow.
Frank
Setting the fin at a perfect 90 degrees.
Here's how I do it.
I have a plastic triangle and cut off the 90 degree corner to clear the fuselage. Photo 165 It is taped to the fin and the stab and guarantees a 90 degree fin placement. Photos 166 and 167.
This triangle has been used for 20 years and about 80 planes.
A great investment.
Letting it cure overnight.
Frank
Houston- we have a problem
This kit supplies 2 types of rudders (photo 174 compares them):
1) the DR1 type circular fin with the semi circular rudder (the one I picked)
2) a more normal fin and rudder. See photo of the two rudders. photo 174, 176
I picked the circular one because this rudder has area below the stabilizer so I can easily add a tail wheel and tiller. This plane is a tail dragger
Two problems
- the rudder hole to clear the elevator was too high (photo 171). I cut the bottom of the hole deeper, inverted the cut-out piece and attached it to the top of the hole (Photo 172)
- the rudder extends about an inch below the fuselage. Once the rudder patch dries, I will trim the bottom of the rudder in line with the bottom of the fuse.
Frank
photos of the tail wheel bearing and the rudder in place.
Second photo shows how much was trimmed off the rudder.
Frank
The landing gear.
This is a (n ab) used Apprentice main gear. Cut out 3 pieces of good ply (not lite ply) and am sandwiching the wire between 3 layers. It then slips into the slot just ahead of the leading edge of the wing. The glue is drying now on the first sandwich layer.
Frank
Finished
Final assembly, control horns installed, pushrods, landing gear, servos connected.
The landing gear block was glued and finished and fit perfectly in the slot. Glued in place with 5 minute epoxy (what else!)
Oops, pilot installed in the cockpit.
Looks great. It feels like it will be a joy to fly.
Frank
Looks great; should fly great too!
Looking good Frank enjoy the maiden and have fun flying this beauty.
Iam still flying my model every weekend.
Ton
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