Rigging tension question

[davec]

I have been slowly chipping away on my Pfalz D.XII, and last week rigged the wings.  I used maxima 2 lb test fishing line, looped through small wire loops glued to the wing and albion alloy .5 mm tubing.  I paused last Sunday.  At that time, when I had attached the last few lines, I saw that a few of the ones I had placed first were now a little loose. I had some travel coming up, so planned to remove and replace the loose lines on my return.

I came back yesterday, to find everything was now appropriately taut.  I rechecked again this AM.  Still taut.  I run a dehumidifier in my workshop.  Humidity and temperature unchanged.

To the best of my knowledge, Santa's elves did not appear and fix my rigging in my absence.

My question is whether it is safe to leave things as is, or whether I should go ahead and replace the originally loose lines anyways.  Are they going to loosen up in the future?

thanks!

Dave

[davec]

I had an additional thought.  I used .005" fly tying wire for the wire loops.  I'm wondering if there were very small changes in shape of the wire loops that equalized the tension between the lines.  If this might be the case, then no need to replace the lines. I used the same wires on my EIII, and the rigging has not loosened in the 8 months since I finished it.

Dave

[lcarroll]

Dave,
   In my experience using (the same Maxima) mono line you can easily make small changes in the structure of your model with tension; usually it will distribute the pressure and thus the tension on the individual lines through the entire wing structure over time. To minimise problems I use a "side/side" sequence, installing a line or two on one side, then the identical twin on the other and so on. The method has served me very well with a few rare exceptions and then the loosening was so minor that a little heat snugged the offenders up nicely. I'd say if they are taut let the sleeping dog lie!
Cheers,
Lance

[eindecker]

I also believe that trying to fix a non-existent problem will only create new ones. The equalizing tension ( which should be only a whisper) as you go along is also a fine method.

If my model does not require actual structural rigging, I rely on EZ Line (or equivalent) to avoid the issue entirely.

[davec]

Many thanks to both of you.  I painted the rigging, and it still looks OK.  Enough other problems with the model (correction - things I learned and will do better next time) that I want to bring this one to the finish line and start on the next.

Now if I can only get the rest of the rigging and landing gear on without knocking the ailerons and stabilizers off again. . .  Next time definitely drilling some holes and reinforcing with brass rod.

I've had trouble threading ezline through the .5mm tubing, and haven't been happy trying to super glue it in place.

Thanks!

Dave

[Des]

WW1 aircraft models I constructed over 6 years ago and rigged with Maxima Chameleon 0.12mm line display no signs of sagging, all lines are still as taut as the day they were fitted. I always use the monofilament where structural strength is required otherwise I use Modelkasten 0.13mm elastic thread which is excellent, this thread paints as well as the monofilament. The secret when using monofilament is not to overtension the lines, this not only stresses the model but can cause eyelets to be pulled from the wings, it also puts too much tension on the mono. There is a very fine line between too much tension and not enough tension, practice will be the only way to determine the correct tension. Like Lance has said, I also use the side/side sequence, I fix one rigging line to one side of the model then do the corresponding line on the other side, this keeps everything in check. The mono and the Elastic line both go through the 0.5mm brass tube twice and CA does a superb job holding them in place, I prefer to use very runny CA as the capillary action will drag the glue inside the brass tube.

Des.

[Pgtaylorart]

Dave,

I also use the 2 lb monofilament to rig. I learned the technique from Des, Bo, and Bertyl. Learn from the best, as it were! What I have found is if you do end up with a slack line, don't cut it out and redo it. A little heat from a soldering iron carefully waved beneath the line will tighten it up nicely. Just be very careful not to touch any of the lines or you will be redoing them. Ask me how I know, lol.😁

George

[Des]

Good advice from George about the soldering iron, I have also heard from other modelers that the hot air from a hair dryer does a great job as well and reduces the risk of melting the mono with a soldering iron.

Des.

[davec]

George and Des - many thanks.  Will try heat if things loosen- so far the rigging continues to behave.  I hopefully still have a soldering iron someplace - got a resistance soldering setup for silver soldering a few years ago, and can't remember where I put my iron.  Fortunately, I never throw anything out.

Have a great holiday.

Dave