Doing repairs

[Erfolg]

I want to repair my Parkzone Stinson Reliant, the rudder being ripped from the fin.

I have removed the plastic film like Selotape, which re-enforced the EPO living/moulded hinge.

I have smoothed both edges down to a smooth, straight line.

Now I want to use hinges which are moulded, requiring a hole to be made.

At first it seems easy, just drill an appropriate hole, a bob of glue etc. and the job is done. Yet being made from EPO, it does not like a drilled hole, tending to tear, certainly not a quality hole.

I have thought of using a hot wire to melt a hole, but I am not sure that this would be great either.

Any experiences of what to do and not do?

[ericrw]

If you need to make an hole in EPO, strengthen it by putting a strip of plastic (such as a defunct credit card) on one side of the hole !

[john stones 1 - Moderator]

I think a sharpened piece of tube would be best for cutting holes in Erf, a drill would be too aggressive. Why not use the tape with the weave in ?

John

[Former Member]

[This posting has been removed]

[Braddock, VC]

If you have some of the contact glue "POR" put a small bead of glue all the way down the fin, similarly a small bead of glue down the rudder. Allow to set (about 15 mins) then lightly press them together.

The POR will have sufficient elasticity to act as a replacement living hinge. With care it is a repeatable repair as using a brand new scalpel trim off the old and replace with new.

[Chuck Plains]

My Max Thrust Riot had pin hinges in th rudder. 3 of them if my memory serves me. and probably glued in with POR type glue

Hmm, the foam won't be so obliging as balsa in keeping the pivots nicely lined up, so my recommendation, if you intend to use that type of hinge would be to just use a spike to make the hole. That will then close up as you withdraw it and provide a tight fit for the hinge 'plug'.

Braddock's suggestion is interesting, because POR sort of welds itself to this type of foam.

Hot glue also works well with Z foam too. As you would be glueing a very small area you could use low temperature glue to reduce the risk of melting the foam. You've probably seen the videos for making hot glue hinges, but that would be difficult with the profiled rudder/tail that I presume the Stinson has.

[Ady Hayward]

Hi Erfolg,

I would consider using the flat hinges C/A'd and pinned but remove the short hinge wire so each individual half can be fitted to the appropriate edge and when done the rudder can be joined using a long wire thus allowing the hinge wire to be removed when necessary to free the rudder for maintenance etc.

Adrian

Edited By Ady Hayward on 24/06/2014 05:48:56

[Biggles' Elder Brother - Moderator]

Why not just replace the tape hinge with new tape?

BEB

[Erfolg]

BEB

It was a moulded type hinge. The type where the EPO was thinned to a few thou, probably about 20.

Some how my dearest wife has manged to rip of the rudder and snap it in half. Of course I have been most reasonable, accidents that could happen to any one, although obviously this is not one of those, plain clumsy.

I have decided to put in the pin hinges, using the tube boring method, which I did last night, into the rudder part.

Since then in the cold light of day, I also found that at the same time, my darling wife, stupidly managed to damage the elevator. Which I am now dealing with. Hopefully I will have fixed this in the next half hour.

After that I will bore holes in the fin and insert the rudder.

As a belt and braces solution, I have some white silicon sealant, which i will use in conjunction with masking tape and a jointing tool, to make a secondary living hinge.

As I was repairing the elevator, I was thinking about a car advert, where a RC plane belonging to a young man, is crashed by a girl friend in revenge for closinghis closing her car door in a careless manner. Is this revenge, for something, could it be, surely not

Edited By Erfolg on 24/06/2014 13:58:24

Edited By Erfolg on 24/06/2014 13:59:17

Edited By Erfolg on 24/06/2014 14:01:59

[Vecchio Austriaco]

Carl, is "she" reading your posts? hope not - or you are in severe trouble.

Was impressed about your 2-post long report - so I could read you really enjoyed going to Greenacres. this is for sure compensating a little transport damage. And also be happy that your better half was accompanying you - not many ladies can be convinced to come.

To the repair itself: can you not slit it open with a sharp scalpel and use a thin cyano type strip hinge with foam proof cyano and a little bit of kick spray?

Regards

VA, still in house renovation mess

[Erfolg]

Gerhard, I am always in trouble, when I am not, I then worry how long it is until I have breathed incorrectly again.

I have now fixed the rudder, fin and tailplane issues.

Although I did put in pointed plate type hinges, I am not sure it was necessary, the silicon sealant seems to have worked really well. I think I first saw it on an open glider that is manufactured by a club member, who had one of his products using a similar technique although much better made. Most of his products rely on a living hinge made from Carbon Kevlar prepreg.

Anyway, I tried it out today, although my assembly has less movement than the original, it moves sufficiently that I can control the model whilst taking off etc.

Pity you did not go, as the event was much better this year, in that I felt confident enough to fly (although not eligible last year no "A". The one thing I was not used to, and no experience of, was the 90 degree cross wind. For my faster models. 2 off ( 3 flights) it was no issue, when landing. In the case of one of my slower models, I could see it drifting across the strip, to the rough stuff, my own fault. On my last model, it was muscled out of the way by a following glider tug, when i decided to go round, I realised that it was not an option, that would have not caused a caffufill, so again landed on the edge of the rough stuff. I am not complaining though, as it was really good fun.

Edited By Erfolg on 25/06/2014 20:16:39

Edited By Erfolg on 25/06/2014 20:17:03