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Re: Californian

Posted: Sat Jan 07, 2017 12:38 am
by Tim H
A brief report before I go to Clayton Green in the morning. The Californian is almost finished, just some detailing to do. I'm happy with some of it, unhappy with some of it and really annoyed about the rest!

The biggest mess up is with the Reg and racing No's which are red. I don't think decals will stick to the awful looking silver finish so I made masks and sprayed. Total disaster! Red acrylic paint doesn't work over silver acrylic paint, and masking tape doesn't stick very well to it either. The photos are very kind but to the eye even the darkest bits of red are pale pink at best.

Hopefully it will fly well or it might get accidentally trodden on :oops: .

Re: Californian

Posted: Sat Jan 07, 2017 10:18 am
by staubkorb
Still an impressive job, Tim! I'm still kicking myself for not getting more info on Antonin Alfery's models in November when I spoke to him. What I hadn't fully realized was the real lack of time as a first time "competitor".

Did a (pre-requisite) "bed test" show promise? I have a feeling that you might be surprised about the potential...

Re: Californian

Posted: Sat Jan 07, 2017 5:50 pm
by Monz
Looks okay as a first foam build to me Tim! The second one will be much better ;)

Re: Californian

Posted: Sat Jan 07, 2017 10:33 pm
by g_kandylakis
I have to agree with Monique. I find it a very brave choice to use this material. Sure, different, but very unforgiving in finishing defect hiding.

I bet the next will be much better. It is only the first 20 that are difficult, by then you will have figured everything out ;)

George

Re: Californian

Posted: Sun Jan 08, 2017 10:17 pm
by Pete Fardell
It was good to see this little beauty in the flesh yesterday, Tim. I know the flight trimming didn't go all that well but this model, and your impressively short build time, has opened up a whole host of possibilities for me. I don't think I'm ready to go all foam yet, but I am now tempted to maybe do a foam fuselage with trad built wings before too long.
By the way, I meant to ask- did you feel it necessary wear a mask when dremelling all that blue dust out?

Re: Californian

Posted: Mon Jan 09, 2017 7:11 am
by rgroener
Tim, your little bird looks great not just o.k. for me. Especially for a first foam model!
If it wouldn't be foam, I would have to try one. ;)
Do you have any pics or movies from your trimming session?

Roman

Re: Californian

Posted: Sat Jan 14, 2017 12:29 am
by Tim H
I really should finish this build log off with a proper flight report as it's nearly a week since the meet at Clayton Green.
Truth is, it didn't fly at all. Pete is kind by describing it as "not going all that well". It was a complete failure. And the worst bit is that I have no idea what, if anything I can do. I am not a trimming expert at all; no background in aerodynamics or anything. My technique is mostly "give it a try and then try something else" and sometimes it works. I know enough to correct clear problems but this model didn't do anything I could analyse. Every launch was different and it never got anywhere near stable flight.
It would roll onto it's back, then dive left, then try to turn right, while jinking left every other moment. I just ended up frustrated. There is usually something that you know needs changing even if it means some workshop time rather than a quick adjustment at the field but I have no idea what to do here. I wonder if it needs a bigger fin, or a bigger tailplane ( I enlarged the scale one to about 20% of the wing area) but that is just guesses. I hope it doesn't need more noseweight as it now weighs a stonking 21.5g without rubber! Balance is at the front edge of the wing reg Nos. Every adjustment of side or down thrust just produced another weird "flight" pattern.

My inclination is to put it away in a box and forget about it. ("Me, built a Californian F1 racer? No No No, you have me confused with someone else sir!") You can't win them all I suppose. Please comment if you have any ideas because I'm out of them!

Some final comments on the use of foam. I didn't enjoy the process much but not because of the dust. I didn't bother with a mask Pete as my lungs have been so abused with different sorts of dust over the last thirty five years that I admit to a pretty poor (and not recommended) attitude to looking after myself V wearing uncomfortable PPE. I didn't enjoy the closeness to ruining something you get. The more you sand the flimsier the part gets until it is so delicate it feels impossible to hold it firmly enough to do the actual sanding. And this model was not thin and light enough! My two aims were speed and lightness and while I achieved the first, the second was nowhere near. I think that you need to be able to sand the rear of fuses to within paper thinness to achieve light enough weight.
Another thing I found was that although I had to make some slightly thicker wings so that they retained their shape properly, they still got damaged and bent during trimming. If my model was still too heavy with wings that vulnerable, I don't understand how Pete Smart and the other guys built light foam wings which were strong enough to hold two or more nacelles plus props and motors on his foam multis without being too heavy or collapsing under their own weight? I will ask him next time I see him because I really can't figure that out.

So my conclusion is, Where did I put that balsa? :D

Re: Californian

Posted: Sat Jan 14, 2017 2:48 pm
by Pete Fardell
Despite the trimming frustrations I still think it was worth doing because it's a good looking little beast, and does at least show how a metal skinned aircraft is much better represented by foam than stick and tissue.
I'd be inclined to try a larger tailplane before giving up and, although it goes against the grain, I'd give a healthy upboost to the dihedral too.