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 on: Yesterday at 06:27:25 AM 
Started by Miguel Poduje - Last post by Bob Reeves
Here are a couple photos of the nose of the Ringmaster I sometimes fly in Old Time. Have a couple other profiles set up the same way and they all work well. Hays tank on muffler pressure, bent tubes epoxied behind engine to carry fuel and pressure lines from one side to the other. Clean, neat and it works..

 on: Yesterday at 06:16:07 AM 
Started by Larry Wong - Last post by Bill Smith
fly great don't they

 on: Yesterday at 06:09:35 AM 
Started by Jim Kraft - Last post by Bob Reeves
I liked Bob Hunt's article on the reverse wingover. I have never been able to do a good reverse wingover, mainly hitting the inverted pull out without it ending up 5 feet too high or in one case at Brodak's 6" below ground level.

 on: Yesterday at 05:21:24 AM 
Started by Mike Griffin - Last post by John Park
I've used dope and balsa dust for fillets plenty of times, and it works well for me: my preference is for non-shrinking dope, or  sanding sealer.  In the old days when planking was a common technique (before we learned how to mould sheet to a curve), I was so rotten at it that I invariably had to use the old trick of squeezing cement into the gaps and immediately sanding over them.  This created its own cement/balsa dust filler, and turned a terrible job into a half-way acceptable one.
On a lighter note, AeroModeller once asked for suggestions as to uses for balsa dust: they received one that read simply: 'Head filler for combat modellers'...!
Happy Christmas to one and all.


 on: Yesterday at 04:57:28 AM 
Started by Brent Williams - Last post by rich gorrill
This being my first full season since re-treading back into the sport 1 1/2 yrs. ago I entered 2 contests, came in 3rd. in beginner, in our contest, my engine decided to call it quits during the contest or I think I could have placed higher. {there's no crying in control line stunt}. 2nd was a speed limit combat event also run by our club. I came in dead last, got my first and only cut and a Sportsman plaque.  My biggest accomplishment was absorbing all the knowledge the member's of "The Philly Fliers" are willing to share with me. As most know we have some great fliers and builder's in our club and they are all more than willing to help me or anyone with their wealth of knowledge.   I completed my first full pattern late in the year it was a little sloppy to say the least but I got it done.  We'll see what next year brings, to me flying is like golf, my other passion, you go out and try to get a little better each time out, do the best you can and just have a good time with your buddies.


 on: Yesterday at 02:40:32 AM 
Started by Mike Griffin - Last post by Curare
Most of my building is done with PVA, (and if you look around there's some good info on using PVA and aliphatics). I have noticed a couple of things that are probably worth mentioning as an addition to John Craig's points.

When building built up structures like an stab, elevator or flap, the lure is to use Cyano's to hold the ribs in place. If you do, and you have massive splashes of CA everywhere, you can hang your hat on the fact that the PVA will not stick to those CA'd areas. Best to flat sand whatever you've built to remove the excess CA and expose as much pourous material to the pva if you're planning on sheeting whatever you've built.

PVA works great on foam, it doesn't attack it but it will seep into between the beads. The temptation is to slather it on, but you'll add weight for not much gain. Also, when gluing things like leading edge stock to a foam core, make sure that you're clean and tidy with your application. PVA while soft, doesn't sand like balsa, and you can end up with a 'rubbery' section that won't sand. It's like trying to sand foam rubber. Tight joints and no excess minimise this.

I'm not a fan of laminating stuff with PVA. Especially doublers in fuselages. Because PVA is an air-dry glue, you'll have the edges dry, and the core will stay wet for a long time (same with sigment too). Also because it's not fuel proof, you're running the risk of a delamination later on in the aircraft's life.

Oh, that acutally brings me to a final point (I know most of this is common knowledge, but someone may find interest in it). The best thing about using PVA's is it's flexibility. I once built a 3m (114") saiplane, using mostly CA. On a blustery day, we were winching it, and lowe and behold I broke the mainspar. The plane didn't just break, it EXPLODED, as all the brittle CA joints were shocked so much they just broke. I lost the entire wing between the wing joiner at the centre and the polyhedral break! I firmly beleive that if the wing had been built with PVA I may have got more back that just the wing tips.

 on: Yesterday at 02:26:01 AM 
Started by Mike Griffin - Last post by Curare
I have to admit, I've never been a fan of the dope and balsa dust trick as a filler. The main reason being that the balsa dust I collect is probably crap.

The place where it collects in enough quantity to make this worthwhile is around my old drememl scroll saw. It's not an ideal medium as it's full of ply dust, sometimes maple dust and carbon fibre dust and whatever else I've been using the sanding wheel for.

It usually ends up and inconsistent glob, which doesn't sand the same as the rest of the model.

Like most of the guys on here, I prefer not to fill, by taking care of the model with pillows, and blankets on the workebench after I've started to final shape. Inevitably you'll get some dings, and if you're like me (a spaz) you'll make more than your fair share. Some can be removed with a simple lick, others will get the water and iron treatment. I still ahve to try that vinegar technique though!

The only thing that gets filler on my planes is fillets. The rest is generally made from balsa. (even fillets sometimes!)

 on: Yesterday at 02:18:24 AM 
Started by Brent Williams - Last post by Curare
I scored a 2nd in the State F2B titles, but that was more because everyone who was a contender above me either crashed out, or had massive problems.

The gap between first and second was CAVERNOUS, but I have a medal, so that makes me smile.

 on: Yesterday at 02:14:21 AM 
Started by Curare - Last post by Curare
Igor thanks for that, I now believe that what I experienced was not caused by what I thought it was initially. As you rightly say, it's trying to subtract myth from fact. I have in my F3A career seen many myths busted, and new ones to spring into play. It's very easy to see an effect, and misdiagnose a cause. One such thing is spiral slipstream. Some guys were running different decalage on left and right elevator halves to 'compensate'. I don't neccesarily think that they'd found THE cure, but they'd found A cure. What the actual problem was may not have been spiral slipstream, or maybe it was, I don't know!

Thanks for all your input gents, even if the fix is simple, I like to think that knowledge of whats causing the issue should lead to better fixes later on. As the old saying goes, if all you have is a hammer, every problem looks like a nail.

 on: Yesterday at 02:13:06 AM 
Started by LCVS - Last post by LCVS
You started this discussion just so you could show that picture.  Very good, Luis.

Not really Howard, but it certainly fit the bill just right, doesn't it???  Layingdown

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