1:4 1928 RRG Professor

[ARUP]

I was hoping to lay the keel on the bottom but no such luck. Making the top and bottom formers has been taking more time than expected. Second pic shows some of the formers before install. The forward most ones required a lot of angled sanding. You can see what is required by looking at the plan's side view as shown in first pic. I did get servo rails and servos installed. I'm using Hitec HS-525-MG servos. The third pic show ply being added to bottom nose section so that a skid mount block can be added later.Again, the last two pics are a stereo pair!







Time for supper!

[ARUP]

Formers for the wing mount pylon structure were fabricated and let into the fuse 'box' structure. Paper patterns were drawn using the plans then fitted into the structure. The first former does not actually attach to the wing. It is for support of the others. It was made in halves using light ply. The second two formers were made from plywood. To fit each into the fuselage box a corresponding side diagonal had to be loosened one end to allow clearance for the former to be 'swung' into place. This wasn't hard work... just fiddly. You can see a wire piercing the pylon portion of the formers. This will be the wing retention pin. Tabs from the wing will hang down into the open pylon so that the wire can capture them. One end of the retention pin will be part of the headrest. At least this will eliminate some bolts! These strut braced birds have lots of nuts and bolts holding them together.









The two similar pics are a stereo pair. Cross your eyes to look at them and if you are binocular then a 3-D effect will occur rendering more detail!

[ARUP]

Kevin, I went back through your thread, too. Good luck with the remodel. I did my house a while back and did much of the work myself so I know firsthand what that can entail!

[ARUP]

TJ, I'm using the Hitec HS-625MG. I set it up so that the release is closed when the horn is toward the nose. When the transmitter release switch is thrown the servo will get a little time to 'ramp up' in torque before any real movement of the release pin occurs. The pin only has to travel about 7mm so an even lesser servo would probably be plenty!.

[Tango Juliet]

What servo do you use for the tow release?

[Melchizedek]

That is such a lovely structure Mike.
Regarding the WW, in the summer I was busy with gobs of overtime. When fall came I began remodeling my home.Hopefully I will get back to the WW in the new year.

[ARUP]

Now that the release hoop is in place it's time to get the release pin assembly fitted. A properly angled platform was built with 1/16" marine grade ply. A 1/4" ply plate was grooved to receive the release pin's guide tube. This plate was glued onto the platform. Next, the servo mount was fabricated. It can be accessed by reaching into the cockpit opening. I try to get this functioning smoothly before putting the external ply skin on the framework. All of these parts tie the nose structure together pretty well so there shouldn't be any problem with the release assembly letting go under less than perfect tow.







While the epoxy cures holding the servo in its mount some one piece ply fuselage formers with integrated pylons will get fabricated then let into the fuselage. Stay tuned!

[ARUP]

Thanks, Dion! So many projects so little time!

[ARUP]

TJ, I move along pretty good but get slowed down, too. This build has been 'brewing' in my brain for a couple of years so I pretty much have the virtual build done! Fleshing it out is fun! Have yours ready for Horizon 2018!

[ARUP]

Hi Bill! Thanks very much!

[Dion Dunn]

Very nice work Michael! Bill

I'll second that - impressive level of usual craftsmanship.

Michael - we need to dig out your frame jigs - I want to build a bike too.

[BStaley]

Very nice work Michael! Bill

[Tango Juliet]

Either you're really moving pretty quickly on this build, or I'm moving really slowly on mine. I fear the latter. Great work so far!

[ARUP]

The release has been getting attention! 3/32" music wire 'massaged' to the contour of the nose to make the hoop. The Dremel was used to roughen it up a bit so the epoxy can grab better then the forward portion painted. The second picture shows the parts 'dry fitted'. A ply plate was fitted into the nose. It has CF tow epoxied to its lower surface. The hoop was epoxied in place next and the CF tow was wrapped over the hoop's legs. Another ply plate fits between the hoop's legs to hold the CF as the epoxy cures. All of this, along with the CF laminated into the nose bows, should be plenty stout for towing duties.





In the first picture is the release pin partially completed. It will fit into the brass tube which will get let into some ply. The pin will be articulated. I hammered one end flat and drilled a hole to fit a link from the servo. This has been done on previous models and works very nice without binding.

[ARUP]

TJ and Kevin (Melkezedek), JimD contacted me to see about helping getting bigger pics put up. We're working on it! Can't make any promises, though.