BEAVER DH C2 no 2 30 IN RUBBER DUMAS KIT 306 Nov 25 2025 to PRESENT

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #60

Fri Jan 23 2026

Testing the Shims

     There are four small quarter moon tapered shims.    #1 is thinnest to #4  thickest.   Each shim is thicker at the top and thinner at the bottom,  on the same shim.

     There are also three large full size shims to test also.

     I should be able to measure the down thrust angle results from the pics.

Pic #1     1107     The fours small shims,   and three full size shims,  are ready for bench testing ....

Pic #2     1098     There is some downthrust already built-in ,   with no shims present.

Pic #3     1101     Small shim #1  is installed,  increasing the down thrust angle of the prop shaft.

Pic #4     1102     A second small  #2 shim is added to the first.    You can see the top thickness of the shim is increasing,  as the shim # gets higher.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #61

Sat Jan 24 2026

Testing the Shims

Pic #1     1104     And here are three shims stuffed in there  -   this is the max space allowed,  as this is all starting to pull the tenon nose block out of the fuse nose mortise  -  good thing that I had extended that nose block in the first place,  to get this much stacking of the shims.

Pic #2     1110     I plan on covering the bottom corners with tan esaki where the wood is thin.

Pic #3     1113     My setup.

Pic #4     1116     I used Studio Glue Stick,  but I don't think it worked too well.    I might try white glue on the other side.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2  30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER  DUMAS KIT 306

Reply #62

Sat Jan 24 2026

Testing the Shims

Pic #1    1117    The plan is to glue these tan tissue strips over the weak bottom corners of the full size shim.

Pic #2    1122    This is the result.  I just have to snip off the excess tissue.

Pic #3    1123    I decided to add more strips of esaki tissue to the other side also.    This time we are using white glue,  which worked better than the Studio Glue Stick.

Pic #4    1128    Pic of two beavers pinned onto my building board plan. 
On the left is Joe H's  (anyone know where Joe H is ?) blue Beaver  flown without wheels,  and on the right is Pete Fardell's award winning Beaver in red yellow and white.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #63

Sat Jan 24 2026

Testing the Shims

Pic #1     1130     We are gluing on reinforcing tissue strips on the other side also now,  with a different set up.    The "master" file folder cardboard ( 0.011" thick),  full size shim,  is sitting partly in,  and around,  the tenon of the noseblock.

Pic #2     1132     Here you can see the tan colored strips that were glued on,  and trimmed up,  and slightly sanded at the tight spots.   Now all three full size shims fit smoothly  onto the nose block.

Pic #3     1134     Here full size #1 is carefully slipped all the way onto the noseblock tenon.

Pic #4     1135     And here is the test fit of  #1  full size shim.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #64

Sat Jan 24 2026

Testing the Full Size Shims

Pic #1     1141     Full size #1 plus #2  shims together.

Pic #2     1145     Full size #1 and #2 and #3 shims together.

Pic #3     1147     Aerial side view of the downthrust from three maxed out shims.

     And that is it for the shims.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #65

Sun Jan 25 2026

Wing Mount

     Well,  here is a setback at a very difficult spot to fix up,  now that the fuse is all done.   In all of the handling and changing of motors, I heard a crack,  and I found it.   Part  B5.   The slanted roof headboard -slash-  Leading Edge Wing Stop/Rest,  now had a shear break at the left side corner.    This is actually a big deal,  and deserves a similar response ....

Pic #1     1150     Here is the crack on  B5,  just to the right of the near pilot's head.

Pic #2     1151     Another view of the crack.    I moved it out of its resting perfect fit for the pic.    I white glued it back in the exact place,  perfectly I think (the surface must be flush for the doubler).

Pic #3     1155     I made some photocopies of part B5.   I cut out a 'rough' file folder doubler,  from the cardboard,  and it is sitting in its spot just above the pilots' heads.   The bottom of the very outside legs,  will be extended down a bit further.
 
Pic #4     1158     Here is a side view of that  eleven thou thick cardboard doubler.   The final one will have that missing extension on the bottom right.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #66

Sun Jan 25 2026

Wing Mount

More progress.

     Good thing that I found this out now,  as I was always worried about that B5 part,  and how it would hold up in a hard landing.  I worked all day on this critical wing mount.   I photocopied a bunch of  B5  photocopies from the original laser cut balsa sheets photocopies.    Through several iterations,  I finally got some exact fitting templates.

     Part B5  needed further strengthening,  after re-gluing the shear break.   The plan was to white-glue onto the front of B5,   a  "doubler"  of  0.011"  thick file folder cardboard,  the same size as the B5 part.    It is a tight fit,  almost touching the back of the pilots heads.   In order to glue the cardboard doubler,  in its place and flat,  I went to the trouble to make two extra 1/16" thick balsa clamping plates,  to sandwich the B5 and the carboard doubler together,  while it dried.    Small clamps should hold it together.   I may put another doubler on the other side of B5 (the LE side),  after we see how the wing will accommodate the second doubler,  that will cause the narrowing of  0.011"  from LE to TE chord.

Pic #1     1161     Cutting out more doublers and taping them onto the file folder cardboard.   The revision is penciled in for the extended legs.     I cut it out wrong,  so I then highlighted the part outline yellow,  and cut it out on the correct lines ....

Pic #2     1163     Test fit of these small clamps,  on the doubler and B5 only.  Now we have to work on the balsa outside clamping plates (same shape as the doubler).

Pic #3     1167     This is the first rushed failed attempt at a  1/16"  balsa doubler clamping plate.    It broke in the same spot.

Pic #4     1169     Sitting on the big balsa block on the left,  are two finished  1/16"  balsa clamping plates,  cut out and sanded to size, and fitted on both sides (different) of the  B5  part.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2  30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER  DUMAS KIT 306

Reply #67

Sun Jan 25 2026

Wing Mount

More progress.  Ready to glue.

Pic #1    1171    Here is the final cardboard doubler.  It has the  1/16" sq center notch on top.  This notch is for a  1/16" sq balsa brace for the windshield,  extending down to the cowl from this notch.

Pic #2    1177    Completed parts.  Two 1/16"  balsa doubler clamping plates,  and one 11 thou cardboard doubler (has the side legs extended down) for the front of B5 .

Pic #3    1178    Big snowstorm blowing across eastern North America.  Bitter cold and blowing snow out here in the southern Great lakes region.  We are getting another  5 inches of snow on top of the last 5" dump that never melted.  My modelling buddies show up for food like clockwork -  there is about 40 or 50 of them. 

Pic #4    1179    One slice of bread per day for these House Sparrows.  Who knows what they eat during the snow like this .... 14 deg F  feels like minus 9 deg F,  winds 15 mph gusting to 22 mph        or
minus 10 deg C  feels like minus 23 deg C ,  winds 24 km/hr gusting to 36 km/hr

Good day for modelling ....   

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #68

Wed Jan 28 2026

Wing Mount

     I am at a a real critical stage with the wing mount to the fuselage in my 30"  Beaver.    The fuse sides' top rail  'saddle',  is not flush with the wing bottom -   there is a long sliver of light shining through the same on both sides  -  it needs a long thin strip of balsa  1/32" x 3/32",  tapered from the middle to a fine point on both end tips.    These will be glued directly on top of the two  3/32" sq side rails of the fuse saddle,  before adding the wing,  to fill the gap.   I also have to reinforce the slanted roof/headrest/wing leading edge stop B5,  that sits right above the pilots' heads.   I broke this B5 piece in a complete shear at the weak right corner bend (which I was able to glue back into its finger inter-locking place - I hope).   

     So and so forth,  I have been working on a "doubler" to glue on to the front face of B5,  to strengthen it up for the hard landings.   Well ,  I think I changed my mind about the cardboard doubler.     With the Beaver fully secured and not moving,  we tried a lot of test fitting of parts to reinforce the wing mount front LE stop,  and to get the wing to sit flat,  on the fuse top side rails.

     I think I will actually use the front 1/16" thick hard balsa clamping plate,  that is already the same shape as B5,  and use that plate as the "doubler" ,  since it fits so well,  barely,  above the pilot's heads.

Pic #1     1182     After securely blocking up the Landing Gear wire axles,  Mandrake and Bloodroot give the fuse the wiggle test.

Pic #2     1186     Here we are making  0.011" thick cardboard doublers,  in the shape of  part  B5.   Also two balsa  1/16"   clamping plates are also made.

Pic #3     1189     Here are some final good pieces to check.   Two cardboard doublers for the rear of B5,   and one cardboard doubler for the front of  B5.

Pic #4     1192     Here we are just using the front and back  1/16" balsa clamping plates,  alone,  to see the fit.

Lastwoodsman
Richard

[gravitywell]

Those nose shim ideas are really cool.  Will have to try that on the next radial build.

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #70

Wed Jan 28 2026

Thanks Glen.

Wing Mount

More progress.

Pic #1     1197    The wing now sits too high,  when adding the rear  1/16" clamping plate.    This would be a good way of increasing the angle of attack.

Pic #2     1209     Two thin strips for the tops of the fuse side wing saddle,  are sitting on the sheeted center section.    One side is flat,  and it gets glued  down onto the  3/32" sq of the fuse side wall top rail.    A taper from the middle to the edge points,  has been sanded in.   Hopefully,  this will glue more contact surface with the wing bottom,  instead of just the Leading Edge and Trailing edge being glued.

Pic #3     1212     Here we are testing the gluing setup for those two balsa strips on the left.   I'm trying to insure that it is glued all the way.

Pic #4     1218     I just stuck some weight onto some balsa cross pieces.   All glued up now and weighted down with just the right amount of coin weights.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #71

Sun Feb 1 2026

Wing Mount

More progress.

     Well,  those thin balsa strips glued up well.    I did a lot of test fitting to see if the wing sits flat on all four sides' gluing surfaces.    I did do a touch of sanding,  and now it seems to contact all four sides.

     I  have decided on gluing the front 1/16" balsa clamping plate to the front of B5,  and I will also glue on a  0.011"  file folder cardboard 'doubler' to the back of B5.

     They now seem to fit just right.    See Pic #4  1126

Pic #1     1221     This pic shows the thin (barely visible)  eleven thou cardboard doubler,  between B5 and the Center Section Leading Edge.

Pic #2     1220  snip     Here is the close up of the tight fit.

Pic #3     1224    And here is the rear view.

Pic #4     1226     Overview of fit with wing.

Lastwoodsman
Richard

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #72

Sun Feb 1 2026

Wing Mount

More progress.

Pic #1     1227     The side wing saddle strips on top,  give a tighter fit to the wing bottom.

Pic #2     1229     You can still see a little bit of light,  but it is a lot less than it was.

Pic #3     1232     A little bit of coins'  weight,   actually holds down the test fit flush all around.

Pic #4     1235     The front  1/16"  B5 doubler is sanded and fitted into place.

Lastwoodsman
Richard

[Marc Guerriero]

Looks like you got the downthrust built in. Nice!

[Lastwoodsman]

BEAVER DH C2   30 INCH RUBBER POWERED  FREE FLIGHT PARK FLYER   DUMAS KIT 306

Reply #74

Sun Feb 1 2026

Wing Mount

More progress.

     Thanks Ekram!    Those three full size shims are not glued in place -  they are just stacked together to show the maximum downthrust available.    I also have four little quarter moon replaceable partial shims of different sizes to experiment with,  before finalizing with a full size shim,  but none of them need to be glued in place,  as I have the rubber motor under constant tension at rest,  holding the nose plug in tight,  at all times.

     I will start trimming tosses with no shims,  as I already have a slight built-in down thrust into the nose cowl,  and I think I have a slight increase of angle of incidence in the wing mount.    The original horizontal thrust line Datum of this model is straight down the fuse from the prop shaft,  with no built-in downthrust at all.

Pic #1     1236     Test fit with the rear  1/16"  Clamping plate.   Checking the clothes pins'  positioning.

Holes For The Wing Tie Downs

Pic #2     1239     I chased out four holes for the  1/16"  aluminum tubes that hold the tie-down elastics.

Pic #3     1241     The two alum tubes are in place on the fuse.

Pic #4     1242     I think I found the limits,  of my ancient digital camera closeups.

Lastwoodsman
Richard