Royal Zero Kit Build into Rufe
#152
Thread Starter
Here is Gerry's comments on making the center float's main strut sides.
Once the balsa cheek blocks were cut out and sanded on a belt
sander to 90 degree side edges, the top and bottom pylon outlines were
transferred to these pieces before shaping.
A block plane and razor plane were used in succession to get it close to
overall initial sanding w/ 60 grit. At this time, all edges were sanded to
the appropriate edge outlines, albeit at a raised angle and highlighted with
a blue magic marker as a visual aid in knowing when to stop sanding. As the
sanding gets closer to the inner line, sanding blocks of 120 grit and 220
grit are used in succession until the blue line is almost gone.
At that point, a "T-bar" sander was used until all edge outlines were
gone, guaranteeing straight edges along the pylon from top to tapered
bottom. The last photo shows how they fit against the ply crutch that forms
the downstrut core.
Once the balsa cheek blocks were cut out and sanded on a belt
sander to 90 degree side edges, the top and bottom pylon outlines were
transferred to these pieces before shaping.
A block plane and razor plane were used in succession to get it close to
overall initial sanding w/ 60 grit. At this time, all edges were sanded to
the appropriate edge outlines, albeit at a raised angle and highlighted with
a blue magic marker as a visual aid in knowing when to stop sanding. As the
sanding gets closer to the inner line, sanding blocks of 120 grit and 220
grit are used in succession until the blue line is almost gone.
At that point, a "T-bar" sander was used until all edge outlines were
gone, guaranteeing straight edges along the pylon from top to tapered
bottom. The last photo shows how they fit against the ply crutch that forms
the downstrut core.
Last edited by chistech; 01-09-2015 at 08:53 AM.
#153
Thread Starter
Once the mid-section "cheeks" of the main pylon were shaped, hollowing
them out was the next step in weight reduction, especially since this wasn't
the lightest balsa I happened to have on hand. The fillet "cuff" pieces that
serve as a transition between the pylon and pontoon were cut and sanded to
the bottom ( widest) outline. I wanted to get as much contour shaping and
sanding off the pontoon to facilitate handling and accuracy. The only way
to accomplish this without adding the deck stringers was to get a 1/8 th
piece of corrugated cardboard, make a series of partial yet equal through
cuts and tape it in place. 60 grit sandpaper was taped over this and the
pylon base was sanded back and forth over this until the pylon bottom was
concave sanded up to the outside edges of the width.
At this point, it was razor-sawed in half and partially outline
shaped, cut to the correct height to fit up against the bottom of the pylon
cheeks and then shaped and sanded w/ progressively finer grits of sandpaper
around a dowel. All pieces were temporarily held in place at this time with
double-sided scotch tape. When the deck finally gets planked, the cuff
pieces will be cemented in first followed by the cheeks.
them out was the next step in weight reduction, especially since this wasn't
the lightest balsa I happened to have on hand. The fillet "cuff" pieces that
serve as a transition between the pylon and pontoon were cut and sanded to
the bottom ( widest) outline. I wanted to get as much contour shaping and
sanding off the pontoon to facilitate handling and accuracy. The only way
to accomplish this without adding the deck stringers was to get a 1/8 th
piece of corrugated cardboard, make a series of partial yet equal through
cuts and tape it in place. 60 grit sandpaper was taped over this and the
pylon base was sanded back and forth over this until the pylon bottom was
concave sanded up to the outside edges of the width.
At this point, it was razor-sawed in half and partially outline
shaped, cut to the correct height to fit up against the bottom of the pylon
cheeks and then shaped and sanded w/ progressively finer grits of sandpaper
around a dowel. All pieces were temporarily held in place at this time with
double-sided scotch tape. When the deck finally gets planked, the cuff
pieces will be cemented in first followed by the cheeks.
#154
Thread Starter
The main pontoon has been removed from the building jig, the
jig-rod exit holes out the backsides have been filled and shaped cradles of
EPP have been Gooped to particle board
shelving material. The main and secondary pontoon supports have been
cemented in place and a tapered reinforcement "sub-floor" has been shaped
with a two way taper and sandwiched in along the sides of the main support.
It was then sanded down flush with the rounded formers and is now ready to
have the remainder of the deck planking to be fitted and cemented to it and
the other adjacent formers.
jig-rod exit holes out the backsides have been filled and shaped cradles of
EPP have been Gooped to particle board
shelving material. The main and secondary pontoon supports have been
cemented in place and a tapered reinforcement "sub-floor" has been shaped
with a two way taper and sandwiched in along the sides of the main support.
It was then sanded down flush with the rounded formers and is now ready to
have the remainder of the deck planking to be fitted and cemented to it and
the other adjacent formers.
#155
Thread Starter
With the remainder of the main float getting buttoned up, it was time to
make ( shape, carve & sand ) the cuff bases to the aft "V" struts and then
sandwich those uprights with balsa and
Sand them to an airfoil shape. Once that was completed, it was time to
finish up the transom by adding the rudder hinge supports, showing the
rudder temporarily in place w/ toothpicks.
make ( shape, carve & sand ) the cuff bases to the aft "V" struts and then
sandwich those uprights with balsa and
Sand them to an airfoil shape. Once that was completed, it was time to
finish up the transom by adding the rudder hinge supports, showing the
rudder temporarily in place w/ toothpicks.
#157
Thread Starter
Hi Tom,
Gerry does follow the thread, I just post the pics and his narratives so he most likely will answer you. Probably a small servo mounted on the top of the wing. It's coming out super nice but I wouldn't expect any thing else from Gerry. I tell him he should just clear half the planes he builds just so people can enjoy his wood working skills.
Gerry does follow the thread, I just post the pics and his narratives so he most likely will answer you. Probably a small servo mounted on the top of the wing. It's coming out super nice but I wouldn't expect any thing else from Gerry. I tell him he should just clear half the planes he builds just so people can enjoy his wood working skills.
#159
Thread Starter
From Gerry:
( As an aside, could you respond to the 2 questions from the previous installment? Specifically, the rudder servo will be on top of the wing and easily connected at assembly by a Dubro
spring actuated ball "clevis". As for the cowling, that beautifully spun aluminum A6M5 cowling that came with the Royal kit is all wrong. I'll be scratch building the Rufe cowling from
blue foam, fiberglass and resin, using the lost foam technique. )
( As an aside, could you respond to the 2 questions from the previous installment? Specifically, the rudder servo will be on top of the wing and easily connected at assembly by a Dubro
spring actuated ball "clevis". As for the cowling, that beautifully spun aluminum A6M5 cowling that came with the Royal kit is all wrong. I'll be scratch building the Rufe cowling from
blue foam, fiberglass and resin, using the lost foam technique. )
#160
Thread Starter
This segment addresses the "cheek" fairings on each side of the main pylon which gives it that streamlined, unmistakable "Rufe" look. Since there's a hole at the top leading edge of the pylon ( which serves as the oil cooler air intake on the full scale ), there's a four louvered shutter that is recessed within. I wanted to show something in there but one problem was the flex-cable housing for the pontoon's rudder is smack in the way of having the shutters in a deep, 90 degree angle to that intake hole. In short, the shutter/louver assembly would have to be parallel to the pylon's vertical leading edge in order to look feasible. Add to that all edges of the shutter ring would have to face forward at an angle that would be parallel to the oncoming airflow, otherwise the ring would be facing upwards in the recess.
I tried wrapping and gluing 1/64th ply and 1/32nd basswood around a dowel and cut everything at an angle as viewed from the side but in doing so, you end up with an oval when viewed head-on. This would have looked wrong when viewed through that round outer intake hole. I ended up shaping a balsa dowel from a wide, horizontal template, doing the aforementioned wrap n' glue, cut it on a bias and when viewed head-on, it is indeed a circle. Using the same materials for the shutters, I cemented them in place and the louvers are pretty much done. ( For the sake of pre-finishing before painting, all wood parts were wicked with thin C/A and sanded. Trying to do so afterwards would be a pain and the risk of breaking it would have been high.)
The next installment will deal with sealing, fuel-proofing and airbrushing the whole sub-assembly to look deeper than what it actually is. The intent is to see something in there without it being obvious or distracting.
I tried wrapping and gluing 1/64th ply and 1/32nd basswood around a dowel and cut everything at an angle as viewed from the side but in doing so, you end up with an oval when viewed head-on. This would have looked wrong when viewed through that round outer intake hole. I ended up shaping a balsa dowel from a wide, horizontal template, doing the aforementioned wrap n' glue, cut it on a bias and when viewed head-on, it is indeed a circle. Using the same materials for the shutters, I cemented them in place and the louvers are pretty much done. ( For the sake of pre-finishing before painting, all wood parts were wicked with thin C/A and sanded. Trying to do so afterwards would be a pain and the risk of breaking it would have been high.)
The next installment will deal with sealing, fuel-proofing and airbrushing the whole sub-assembly to look deeper than what it actually is. The intent is to see something in there without it being obvious or distracting.
#161
Thread Starter
Hello All,
Thought I'd add this info. If any of you have purchased the Rufe short kit by Royal Farms you can purchase the cowl and canopy from Fiberglass Specialties. Cowl and canopy cost $55 and are part numbers: RL-8, RL-8-C. I just received an email from Craig @ Fiberglass Specialties saying that they are still available purchase and are still being made.
Thought I'd add this info. If any of you have purchased the Rufe short kit by Royal Farms you can purchase the cowl and canopy from Fiberglass Specialties. Cowl and canopy cost $55 and are part numbers: RL-8, RL-8-C. I just received an email from Craig @ Fiberglass Specialties saying that they are still available purchase and are still being made.
#162
Thread Starter
After the oil cooler louver assembly and screen backing (radiator) elements were finished, they were airbrushed with KlassKote aluminum and flat black and cemented in place. To represent the aluminum intake cover plate, a 1/64th ply pieces was cut to shape and the entire backside brushed w/ 30 min. epoxy to fuel proof it and then all edges were cemented in place with C/A. This was plenty strong enough and the remaining depth on the exterior was covered with carpenter's white glue and it too was edge cemented with C/A. Once the outer thickness which protruded beyond the surrounding pylon was sanded flush with everything, I decided to cut the intake porthole after everything gets resined, glassed, primed and sanded in order to keep all the sanding dust and slurry out of that inner area. It will get cut and plugged w/ wet tissue just before the final exterior color gets sprayed. Time to move on.
#163
Thread Starter
Gerry sent me this today. Apparently after ingesting too much balsa dust and CA fumes! LOL
Ted-O, I must be getting crispier in my old age. After re-reading my text in the last blog post, I mentioned using white glue on the exterior of the 1/64th ply cover where the porthole will be cut out but failed to mention the 1/16th balsa that was glued and sanded flush over that to make up the gap difference.............. not just glue, as printed in the text. Wicked DUHH.
Ted-O, I must be getting crispier in my old age. After re-reading my text in the last blog post, I mentioned using white glue on the exterior of the 1/64th ply cover where the porthole will be cut out but failed to mention the 1/16th balsa that was glued and sanded flush over that to make up the gap difference.............. not just glue, as printed in the text. Wicked DUHH.
#164
Thread Starter
With the main float getting its second coat of resin, it was dry sanded to an eggshell finish w/ 320 sandpaper and is ready for priming once it gets warm enough outside to do so. A water rudder control horn was fashioned out of 1/16th circuit board material and a corresponding slot was cut into the rudder from the trailing edge forward. The horn was cemented in place and a strip of 1/16th balsa fill glued in behind it and sanded flush. At this time, it was glassed & resined and fitted in place with a threaded inner brass tube that slides into an outer tube that's glued inside the rudder post hole. With a "Z" bend screwed into the Sullivan control cable, everything fit cleanly for a very smooth, easy side-to-side pivot. On to the tip floats.
#166
Thread Starter
PS: I told Gerry that he should leave the Rufe in bare wood, just glassed because his work is so pretty!
#167
Thread Starter
After making up a jig, all tip-float bulkheads were cemented in place and the "waist" planking was glued in place before planking the bottom in order to keep everything rigid and lined up.
Now everything you see here is going to be repeated on the other remaining tip-float and then both of them get an upright holding jig made before the topsides get planked. I've got a good mind to special order some contest ( read that as light ) balsa to plank the uppers since there's a LOT more bending and curving going on at this point.
Now everything you see here is going to be repeated on the other remaining tip-float and then both of them get an upright holding jig made before the topsides get planked. I've got a good mind to special order some contest ( read that as light ) balsa to plank the uppers since there's a LOT more bending and curving going on at this point.
#168
Thread Starter
Once both tip floats were bottom planked, an upright holding fixture
was constructed from EPP foam for the cradles and AZAK PVC for the base.
While waiting on a 1/8th" light balsa shipment to plank the topsides, all
end cap pieces were cut to shape, ready to be tack-cemented in place when
the topside planking gets finished.
was constructed from EPP foam for the cradles and AZAK PVC for the base.
While waiting on a 1/8th" light balsa shipment to plank the topsides, all
end cap pieces were cut to shape, ready to be tack-cemented in place when
the topside planking gets finished.
#169
Thread Starter
Once the left Rufe tip float was completely planked, nose and tail blocks were cut, rough shaped, weighed and quartered using the above and side view outlines as a guide to keep the whole
deal as even and symmetrical as possible. All blanks were mixed and matched for an even weight distribution for both tip floats. The four pieces of nose blocks were tack-glued in place and
sanded to a pretty close final shape, then popped off, hollowed out, final cemented in place and then fine sanded. The same procedure applied to the transom blocks and the whole deal fine sanded and ready for glass & resin. Now onto the right tip float to repeat the entire procedure, after which the wood fairings for the struts will be undertaken in the next installment.
#171
Thread Starter
At this stage of the Rufe tip-float build being finished, it was time to complete the struts. I started at the strut base by cementing the actual outline of the strut "cuffs", ( 4 duplicate halves of 1/64th ply ) to the ply upright stub at the top of the floats. Four pieces of balsa block were rough-shaped and fitted in place and sanded until I reached the oval shaped outline. 1/8th ply extensions were epoxied above the base stub and balsa side pieces, reinforced by 1/64th ply on the inside ( with a space to allow the wire strut to be sandwiched in ) were also epoxied in. A template was made of the strut cross-section and this outline was transferred to the tops of the cuffs and the ends of the strut "sandwich" and everything was evenly sanded to all specified outlines, guaranteeing uniform symmetry
#172
Thread Starter
Gerry has finally gotten back to his Rufe. Here's the latest.
Pic #5584: Cardboard template drawn up with pertinent datum lines for main float screw-down post, along with basswood strip running down centerline. I set this up on the main pontoon to
check if the "V" struts were dead center. If they were, the datum lines off the template would be taken verbatim and transferred to the wing bulding plans. As it turned out, the V-struts
weren't absolutely parralell to the pontoon centerline. The change was taken into account on the cardboard pattern and transferred to its desinated wing half.
# 5585: All parts, modified and otherwise, laid out on the main table, along with the wing sheeting already pre-joined.
#5586: Hybid wing construction in effect, pinned down where possible and cemented in place. Not seen here was the trailing edge sheeting that was glued in place to dry overnight.
At this point the original Royal instructions call for the assembly to be removed from building board and placed upside down to have other parts glued to it. Hope I don't lose the
wash-out. The instructions also call for the opposite wing to be framed up.
Pic #5584: Cardboard template drawn up with pertinent datum lines for main float screw-down post, along with basswood strip running down centerline. I set this up on the main pontoon to
check if the "V" struts were dead center. If they were, the datum lines off the template would be taken verbatim and transferred to the wing bulding plans. As it turned out, the V-struts
weren't absolutely parralell to the pontoon centerline. The change was taken into account on the cardboard pattern and transferred to its desinated wing half.
# 5585: All parts, modified and otherwise, laid out on the main table, along with the wing sheeting already pre-joined.
#5586: Hybid wing construction in effect, pinned down where possible and cemented in place. Not seen here was the trailing edge sheeting that was glued in place to dry overnight.
At this point the original Royal instructions call for the assembly to be removed from building board and placed upside down to have other parts glued to it. Hope I don't lose the
wash-out. The instructions also call for the opposite wing to be framed up.
#174
Thread Starter
After quite a few interruptions ( life getting in the way ), more progress on the wing began to take place in succeeding installations: My use of 1/64th ply on all trailing edges allows me to obtain a sharp but straight trailing edge without being fragile. It's all worth the added effort.
Photo 5588 - 89: Underside of wings showing flap bay and flap bay leading edge.
" " " " 90: Wing trailing edge w/ 1/64th ply and pre-drilled 3/8th sq. hardwood edge "set".
91: Ply edge epoxied in place on the pre-beveled underside edge w/ edge set hammer-pinned in place.
92: Ailerons cut free from the wing & placed upside down for ply edging and pinning.
93: Aileron bottom sheet in place w/ pinning edge hammered down. ( Note the kerfs in the outer edge of the hardwood pin-strip to better follow the outboard curve of the aileron.)
94: Both flap pieces cut to shape. ( 1/64th ply outer side and 1/16th balsa for inner .)
95: 30 min. epoxy applied to inside face of 1/64th ply w/ serrated credit card to evenly distribute the epoxy. Balsa side was added & both flaps placed under plate glass with a decent
amount of weight added to keep it dead flat while the epoxy dried overnight. ( More pics & text to follow.)
Photo 5588 - 89: Underside of wings showing flap bay and flap bay leading edge.
" " " " 90: Wing trailing edge w/ 1/64th ply and pre-drilled 3/8th sq. hardwood edge "set".
91: Ply edge epoxied in place on the pre-beveled underside edge w/ edge set hammer-pinned in place.
92: Ailerons cut free from the wing & placed upside down for ply edging and pinning.
93: Aileron bottom sheet in place w/ pinning edge hammered down. ( Note the kerfs in the outer edge of the hardwood pin-strip to better follow the outboard curve of the aileron.)
94: Both flap pieces cut to shape. ( 1/64th ply outer side and 1/16th balsa for inner .)
95: 30 min. epoxy applied to inside face of 1/64th ply w/ serrated credit card to evenly distribute the epoxy. Balsa side was added & both flaps placed under plate glass with a decent
amount of weight added to keep it dead flat while the epoxy dried overnight. ( More pics & text to follow.)