Sandringham Repair

[piker]

Alright.  As ugly as it is at this point, I'll take pictures as I go along for documentation purposes.  As long as you promise not to judge 

[Papa]

Yes Robert, lot's of pictures, remember Simon only reads the comics.

Or as my grandson calls them Graphic Novels.

LOL

Jack.

[piker]

O.K.  Simon keeps telling me to stop yapping so much and post more pictures, so here ya go.

[sihinch]

Way to go, Piker!  And thanks for posting.

So do you use tape to hold the pieces together whilst you glue them?  Does that work?  What type of tape is it - the blue one?

[piker]

Well, I wanted to describe what the pictures were all about, but... well, YOU know   

O.K.  Since you asked...

The early stages of putting all the bits of foam back together consisted of gluing in the chunks missing from the lower section of the internal fuselage.  Eventually I got to a point where I could bring the two sides, that were split apart along the keel, together and most recently I've been adding the major chunks to fill in the top of the nose section.  The other pictures show a couple of splits at the tail end brought back together.  So, initially I was applying the 5 minute epoxy and holding the bits of foam in place until it stabilized.  But now that the shape is coming back together, I'm able to glue and tape around the structure as you can see.

I'm using the blue painters tape, the one intended for delicate surfaces.  It has a much finer texture than regular blue or standard masking tape, and I happen to have it in my shop.  It doesn't stick to the epoxy, so removal is easy.  I know Michael described taping over epoxied seams as a way to flatten any excess epoxy to help create a nicer surface, especially in foamies that will not be sanded and glassed. 

The red tape you can see is normally used for sealing the vapour barrier in house construction.  It's quite strong and has a very strong adhesive.  The adhesive can stay attached to the work surface, so I certainly wouldn't use it on anything delicate.

[Andy Hoffer]

Great inspiration for members of Foam Busters Anonymous!

Andy

[piker]

The major bits are back together, but nothing more yet.  However, this is a fairly major milestone as the plane has taken shape again and the rest is simple structural stabilization and filling, sanding, and fiberglass work.  The tricky part of a repair like this is getting the major structure back in shape with reasonable alignment.

Last night I reattached the outer portion of the wing.  This, as with the fuselage rebuild was a little stressful as there's the risk of rebuilding it crocked.  I think it's pretty good, so I assembled the plane to review the overall alignment before I move on.

Next step is to repair the rest of the minor breaks and fill the rest of the missing bits in the fuselage (specifically on the port side near the cockpit).  Then, I can give it a rough sanding to knock off the rough, high points, then filling, etc.

BTW, if you look at the picture of the right side of the forward fuselage, you can see the regularly spaced slices where the spinning prop contacted the nose during the crash   

 

[piker]

What caused the crash? Saw this model fly in the past and it seemed very well behaved.
Field a bit too tight, and you let it get too slow on the turn to final?
Perhaps you could add some flaps in the rebuild to help slow it down for landing?

Pat MacKenzie

Hey!  I realized the never answered your question, Pat.  It's simple.  I screwed up and stalled as I was trying to bring it in slow for landing.

I had actually decided to never flying the Sandy from land anymore because it's really hard on the hull and the tip floats, and we've been doing a lot more float flying lately, so there was really no need.  The planes weighs 16 lbs and to land nicely on the rigid hull the plane needs to be greased in.  I had planned on approaching from the south, so I could get a nice, low, straight run in and not risk over shooting the landing strip, and the winds were from the south but quite gentle.  Then Glenn (yes it's Glenn's fault) said I was crazy to do that, so I approached from the north.  I guess I just slowed it down too much, expecting it to float in nicely, when it just rolled out of the sky.  I MAY have ben able to power up and get the heck outs there, but I was automatically in minimizing the damage mode and let it drop I n with power off.  If I had powered up and it still went in, the damage would have ben more extensive. 

Re. flaps:  I had actually built the wing with scale "Gouge" flaps that are similar to Fowler flaps, but run on a track system to extend rearward over a gradual arc.  The result was that they increased wing area initially, then introduced increased chamber as they rotated downward.  I never came up with an adequate and reliable way to set-up the track system, so In the end I just glued them on and filled the seams in an efforts to get the dang plane finished.  I've never really regretted eliminating the flaps as the plane performs well without them... well, until that day    Actually, it would have been fine if I had just kept the speed up a bit.  Pilot error for sure. 

[Michael]

The repair is really looking good; I'm happy to see it looking like an airplane again.

The front view show shows that it's very symmetrical.

As always, well done!

[piker]

Thanks!   

There is an indent on the right side as a result of the crumpling of the nose.  That's why the left side is also pretty smashed up.  The ugly scar on the right side it the result of my having to cut the glue joint open and space it apart by 1/8" to get the side reasonable flat, and the nose aligned.  The remaining indent will have to be fixed with filler.

[piker]

Just a little bit of work done last night... I reattached the motors as three of them were hanging by the wires.  I also ran each one up to check if the ESCs were still good, if any of the wiring (power and ESC control) was damaged or if any of the prop shafts were bend.  All checked out just fine.

And at lunch today I went to Plastics World, for the first time... (why didn't I know about this place before?) to get some fresh epoxy, fiberglass, and micro balloons.  I'm now all ready for the filling and patch glassing of Sandy.

[Papa]

See! God favours the just.

Moving right along and looking good.

Jack.

[sihinch]

Tell us more about Plastic World

[Michael]

http://plasticworld.ca/

Jack and I purchased fiber-cloth there.

[Andy Hoffer]

I've shopped there several times for glass cloth and East System epoxy resin.  Last time I was there they did not have 1/2-ounce cloth, so call before you go to make sure they have what you need. 

Andy