Build Log Hkm 1:2.5 Asw 28

[hkm-usa]

Rick,
I like the brake mod, very nice.

I used a much more substantial servo on the gear (360oz I think), If I take the gear doors of, I am convinced I could make my model do pushups.

there are a lot of details built into the model that I didn't notice until I got to build it. the gear doors for one, are a work of art by themselves. small things I had not thought of before like wing servo covers that match the bottom of the airfoil wing curve are another. everything else I have ever seen was just flat. just some nice small detailes..

Steve R,
each servo is individually adjustable through the transmitter. with 12 seperate inputs, I don't have to gang together any servos and mechanically match them

regards,
JL

[hkm-usa]

sorry steve, yes it does have rf filtering as well..

JL

[scalebldr]

Shots of elevator and rudder install. 11/11/06

Elevator
I used some flat aluminum plate and made a insert for the elevator control arm. Notice I have extended the clevis hole aft past the bottom of the arm.

Make a slot in the elevator to receive the arm, to the underside of the top surface. Then make a slot 90 degrees to each side of the first slot, inside the elevator, making a + shape. Fit the arm inside the slot, mark a line on the arm to show the amount you will be bonding, drill some holes in the part of the arm that will be bonded. This way you have a secure mounted arm.

The push rod is a carbon tube with allthred inside, with nuts at each end to
capture the rod. The rest is easy.

Rudder
I used 4mm aluminum fittings for the carbon rudder hinge and rudder control arm.

I cut off the top of the inserts to make clean looking fittings.
For the hinge, remove the flat section of the threaded control arm and cut a slot to receive a screwdriver, at the other end drill a hole to receive the hang rod.

Drill a hole in the bottom of the rudder in line with the rudders center line, for the insert. Install the insert with the hinge rod inside the insert, this will keep the rod straight, be careful don’t get CA on the rod or threads!.

Tape the rudder to center and mark the center of the control horn inline with the rudder fairings back edge. Install the insert by drilling an additional hole in the LE of the rudder to allow you to get epoxy to the inside of the rudder, and bond the insert.

Mounting the rudder servo is easy and in this case I used a left over aluminum servo mount with a plywood backer. Every one has there way of doing this. Just keep it clear of the retract arm.

One tip, I use masking tape on all serfaces when using epoxy, it keeps things tidy.

BFN, Rick

[Big Nuts 181]

That looks awsome Rick, nice to see some of the big guns showing everyone else how it all works also nice to be able to compare notes with you. Tell me just a point of interest, on your rudder pushrod I notice you use a full length pushrod ala Graupner as oposed to closed loop or a rear mounted rudder servo with a short pushrod, is there any particular reason?? and is there any wire up the inside of the pushrod to prevent the rods from expanding and contracting in the heat??

cheers Ross.

[crakob]

Hi there,
i'm also intersted in the 28. ( I will build in a AFT up and go )
http://www.klapptriebwerk.de/aft25en.htm.

Have you any ideas regarding the final weight ?

christian

[scalebldr]

Originally Posted by Big Nuts 181

That looks awsome Rick, nice to see some of the big guns showing everyone else how it all works also nice to be able to compare notes with you. Tell me just a point of interest, on your rudder pushrod I notice you use a full length pushrod ala Graupner as oposed to closed loop or a rear mounted rudder servo with a short pushrod, is there any particular reason?? and is there any wire up the inside of the pushrod to prevent the rods from expanding and contracting in the heat??

cheers Ross.

Hi BN 181, Thanks for your input. The model came with installed push rod tubes right and left. I used the kit parts because I did not want to add any additional weight in the tail, trying to keep things light. The glass push rod is light and very stiff. As for heat, I don't beleave it will be a problem, I always do field trim adjustments any way. Rick

[scalebldr]

Originally Posted by crakob

Hi there,
i'm also intersted in the 28. ( I will build in a AFT up and go )
http://www.klapptriebwerk.de/aft25en.htm.

Have you any ideas regarding the final weight ?

christian

Hi Christian, I see your using the Schambeck up and go, Very Nice! I am not sure about your all up weight because I don't know that units weight with lipo's and all. I beleave that unit is light and does not efect the C/G that bad. Keep us posted with install photos, we all would like to see your project as well. Where are you located? Rick

[SteveR]

Hi Rick,

Can you elaborate a bit more on how you setup the rudder. Did you cut off the flattened portion of the inner threaded piece, slot it and drill a hole in the other end to accept the rudder hinge pin?

TIA,

Steve

[crakob]

Hi Rick,
i guess there was a little misunderstanding.

I ment the aprox. weight of your plane. The weigt of the AFT25 is about 1.7kg. The 10S4P TP-Lipopack adds an other 1.6 kg.

I´v read, something about 17 kg for the plane as a Sailplane. Can you confirm that.
It than would be interesting to know, how much lead?(the heavy metall) youhad to place in the nose.

Christian

[scalebldr]

Originally Posted by SteveR

Hi Rick,

Can you elaborate a bit more on how you setup the rudder. Did you cut off the flattened portion of the inner threaded piece, slot it and drill a hole in the other end to accept the rudder hinge pin?

TIA,

Steve

Hi Steve, yes what is normaly the control arm that recives a clevis, was modafied as you discribe. This works for almost all rudder installs. Rick

[scalebldr]

Originally Posted by hkm-usa

sorry steve, yes it does have rf filtering as well..

JL

John, can you answer CRAKOB's question in this thred on the all up weight of the 28.
Rick

[hkm-usa]

CRAKOB, my 28 is 17.2kg. as far a weight in the nose, I have no clue. 2 brass rods, 1/2 inch in diameter, about a foot long, filled with solid lead.

JL

[Big Nuts 181]

are we there yet , are we there yet any word has the model flown yet????

[scalebldr]

Originally Posted by Big Nuts 181

are we there yet , are we there yet any word has the model flown yet????

No not yet, Work is getting in the way, having a bit of a slow down. Will be working on cocpit seat tray next, along with mounting wing servos. Rick

[crakob]

Originally Posted by SteveR

Rick, why stop at 7 meters when you can go straight to a 9 meter fully molded 9 meter ASW-28?! Check out this beauty spotted in Interlaken this summer. It was nothing less than spectacular!

Regards,

Steve

Hi, just for the record,
the TB-ASW28 ist not fully molded but nevertheless its an awsome ship.
Here ist the Homepage of the owner.
http://www.marcomani.ch/ASW28-18.htm

the video ist great

Last week i visited HKM and had a first hand look at the 28.
Realy perfect craftsmanship ! And it´s HUGE !

Sadly the upandgo from www.klapptriebwerk.de does not fit into the fuselage. The fuselage is too narrow. ( 500mm aft of the main wing joiner you´ve got to have 150mm clearance in height)