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-   -   Proud Bird Construction Thread (https://www.rcuniverse.com/forum/q-40-racing-155/8385036-proud-bird-construction-thread.html)

sahartman21 07-18-2009 06:24 PM

RE: Proud Bird Construction Thread
 
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Drill holes for the engine kill.

This is a piece of music wire that is pulled tight to shutoff the fuel supply. The tubing is compressed between the music wire and the engine mount.

sahartman21 07-18-2009 06:31 PM

RE: Proud Bird Construction Thread
 
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Install the firewall and other parts back inside the fuselage.

Tape the spinner to the fuselage so that parts don't move while gluing.

Cut some fiberglass cloth into small pieces.

Mix about 1/2 ounce of 30 minute epoxy and glue the back side of the firewall. Apply the cloth and mix. Move the epoxy covered fiberglass pieces to the glue joint and work in as needed.

Once the firewall is properly epoxied move parts out of the way to let dry.

sahartman21 07-18-2009 10:52 PM

RE: Proud Bird Construction Thread
 
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This model has functional cooling vents behind the cylinder head.

The vents are opened with a Dremel tool.

A piece of cardboard is fiberglassed in place.

sahartman21 07-18-2009 10:59 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
Apply some epoxy to the front of the firewall.

Add some fiberglass cloth pieces to the surface and spread the mix to the firewall/fuselage joint.

Reinstall the motor mount and apply 6 -32 bolts to the front of the mount.

Apply some epoxy/fiberglass mixture over the bolts to hold the mount in place

sahartman21 07-19-2009 08:45 PM

RE: Proud Bird Construction Thread
 
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My LS Jett is installed similarly.

I chose to install a motor mount with needle valve assembly.

Temporarily install firewall, motor mount, motor, plywood spacer, and spinner.

Tap the firewall forward until it is against the motor mount.

Tack the motor mount to the firewall with CA.

Remove the spinner and motor.

Use a long drill bit to drill the holes for the bolts.




sahartman21 07-19-2009 08:52 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
Drill the holes larger for the blind nuts and install them.

Temporarily install the motor mount and locate the engine kill. It is located in a different location due to the use of the motor mount with needle valve assembly.

Once you are satisfied with the engine kill reinstall the parts.

Install a 1/64" plywood spacer between the spinner cowl. Tape them to the fuselage to allow for a straight installation.

Apply about 0.4 ounces of epoxy to the firewall and apply pieces of cut up fiberglass cloth. Mix the cloth and glue as needed and work to the outside edges.


fizzwater2 07-19-2009 10:19 PM

RE: Proud Bird Construction Thread
 
Scott - are you using a thin spacer between the back of the spinner and front of the fuse when you tape things together? that way when you pull it out, you end up with a nice even small space between the spinner and the fuse.

I thought I saw a small ply ring in there, but didn't see it mentioned in any of your pictures / posts. Just wondering, that's what I remember doing when putting firewalls in glass fuselage planes.


sahartman21 07-19-2009 11:06 PM

RE: Proud Bird Construction Thread
 
Yes,

There is a plywood spacer between the spinner and the cowl.

How's the racer coming?

fizzwater2 07-20-2009 07:08 AM

RE: Proud Bird Construction Thread
 
I haven't even cut out the 1/4" balsa parts for the new tail surfaces yet. Spent this weekend running around to farmers markets, etc, with my wife. Had some great fresh corn, peaches, and green beans, though! :)


sahartman21 07-20-2009 09:37 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
Make an air tunnel out of cardboard and glue it in place. Reinforce it with fiberglass cloth.

Mix up some epoxy and chopped fiberglass cloth. Apply this mix to the joint between the firewall and the fuselage side. Apply a thin layer of epoxy over the firewall and install the motor mount.

Test fit the motor and adjust parts as needed. Remove the motor and install 6 x 32 screws in the front holes of the mount.

Apply some epoxy and chopped fiberglass cloth over the screws and shape as needed. Allow to dry.

twitte1 07-21-2009 06:46 AM

RE: Proud Bird Construction Thread
 
Scott,

Are the 6x32 screws attached to something? Or are they used as extension on the mount and the epoxy/glass pieces gooped around the screws to hold them to the fuse side?

Trey

sahartman21 07-21-2009 12:47 PM

RE: Proud Bird Construction Thread
 
A pair of 6 x 32 by 5/8" screws are screwed into the front of the mount.

A mix of fiberglass and epoxy is dabbed onto the screws and provides additional support for the motor.

daven 07-21-2009 03:32 PM

RE: Proud Bird Construction Thread
 
Sahartman, et al.

The 6/32's in the front have been used for some time to tie the front of the motor mount to the fuse (thus lessening vibration).

In the last couple of years many racers have gone to either 1/8" aircraft ply, or G10 cut into the shape of a "C" that bolts to the front of the motor mount and connects under the motor to the whole bottom of the fuse. If this doesn't make sense, I can take a picture. Doing it this way gives you more contact to the fuse, and actually uses a little less glue than the blobs of epoxy/chopped carbon/glass/and Cab-O-Sil that we use to use.

sahartman21 07-21-2009 09:03 PM

RE: Proud Bird Construction Thread
 
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Here are a couple more photographs showing the installation using the motor mount with rear needle valve.

sahartman21 07-25-2009 08:16 PM

RE: Proud Bird Construction Thread
 
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I vacuum bagged another wing today.

It was done in one piece the same as shown earlier in this thread. The T pins are temporarily used to hold parts in place until the tape is applied. The pins are removed prior to putting it in the vacuum bag.

I'm working on two Proud Birds at the same time to be more efficient during the building.

sahartman21 07-31-2009 08:51 PM

RE: Proud Bird Construction Thread
 
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Work continued on the wings the past couple days.

The leading edge was glued on and shaped.

The landing gear blocks were added. The aluminum landing gear is taped in place as a frame of reference to make sure the landing gear block is glued on straight.

Wing tips were glued on. They were temporarily held in place using masking tape.


P. Johnson 07-31-2009 09:55 PM

RE: Proud Bird Construction Thread
 
Great Job Scott, Did you happen to install two ribs to attach the landing gear blocks to ?

sahartman21 08-01-2009 11:52 AM

RE: Proud Bird Construction Thread
 
The wing has a 1/8" thick plywood dihedral brace and has riblets to provide support for the landing gear block.

I added a couple pictures in the earlier posts.

P. Johnson 08-01-2009 12:47 PM

RE: Proud Bird Construction Thread
 
Awwww..Now I see them, good job

sahartman21 08-01-2009 06:44 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
The wing tips were roughed out using a razor saw and pocket knife.

Then sand them with some 60 grit sandpaper to get them to shape.

Continue to sand until they are roughly the same size and shape.

sahartman21 08-01-2009 06:47 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
Shape the trailing edge with a razor plane and sand paper.

Continue to shape the trailing edge until the 2 ounce glass cloth shows.

Then shape the leading edge and contour of the wing to fit the wing saddle.

Continue to sand the wing to a smooth surface.

sahartman21 08-01-2009 06:50 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
Cut some widths of 2 ounce fiberglass cloth to 14", 6", and 3". Tack these to the wing center section with 3M 77.

Mix up about 1/2 ounce of Skin It epoxy. Apply to the fiberglass and squeegee off the excess epoxy.

Sit out of the way to dry.

The other wing was done the same way.

sahartman21 08-04-2009 10:02 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
The horizontal stabilizer is made from a sheet of 1/4" thick balsa.

The parts were glued together and then slotted with a slotting tool. That is made from a hobby blade between a couple pieces of 1/8" ply.

After slotted add some strips of 1/64" thick plywood. They are glued in place with thin CA glue.

sahartman21 08-05-2009 09:46 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
The tail surfaces are shaped with a sharp knife first.

Follow with a razor plane and then coarse sandpaper.

The surface is relatively thin compared to sport aircraft.

sahartman21 08-05-2009 09:49 PM

RE: Proud Bird Construction Thread
 
1 Attachment(s)
Cut the hole in the fiberglass flaring to fit the tail surface. I used a Dremel tool and cut off disk.

This will have to be done by trial and error.


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