I think Jack Sheeks used to fly all his models while in clear in case he had to cut back into the model for any reason. I would say just make sure all cracks are filled, nothing for fuel or exhaust to creep into, and keep the flights to a minimum. They as soon as you finish the last test flight, start cleaning with soap and water!!. Maybe alternate that with Prepsol or similar product. Then when finished, CLEAN IT Again!! Good luck with it!
   Type at you later,
    Dan McEntee

Thanks, Dan and Tim. Yes,I need to verify fuel tank size aganst run tme. Might need to reconstruct front end for larger tank.

Will mix denatured with methanol for a cleaner.

Dave…

If you have denatured on hand I'd suggest you use that, and don't mess with mixing it.  As near as I can tell, 99% isopropyl is about as good as the stove fuel I use at removing castor oil residue -- I just use the stove fuel because it's cheaper.

on 1.5 oz of 10%  on an oversized Shark 15  my KC .061 runs for 8 min ,06 sec  with a 5.5-2 APC

   Hey RAD!! Over sized Skark .15 or undersized . If it's reduced, what wingspan?  I think I reduced the plans at one time but have to dig them out.
  Type at you later,
    Dan McEntee

Gents

Will do, Tim!

The little uniflow tank I made to fit the Pinto space carries just under an ounce. Seems skimpy to me, thus my intent to fly before finishing the model. I too anticipate 50-feet lines of 20# Spectra for test flight. The 061 Big Mig can turn the 5x3 prop at 20K on 15%. Yikes!

Dave Mo…

     Plumb up your tank so it will be able to run on standard venting and uniflow. , with and without pressure, just to make it easy for you to switch around while you are testing. On the Doodle Bug Brothers model I have a .061 on, it had worked best running on standard venting with no pressure, so far. Model size, weight and how draggy it is will dictate how you run the engine. While I was researching mine, some guys said to run them balls out and high RPM and at that setting it won't use a lot of fuel and some said less that an ounce, around 3/4 ounce I think. I'm on really long lines on this airplane, and the engine seems happiest with the APC 5.5-2.5 but lap time are too fast when it's at full lean, so I have dialed it back to the 18,000 range , if I'm remembering correctly. Yours is a full fuselage model, so depending ion what it weighs, it will be a different animal and you may need to run that high RPM mode. Head gasket count, and even different types of glow plugs will affect the run. I'm back with the standard Norvel/NV button head/glow plug, but got one of the Kamteknic heads for Nelson style plugs to try and even tried Cix glow heads, which fit fine and would work well if you needed or wanted to lower compression. There is a lot you can do with these engines, you just have to run them like they like to be run, and not even try to run it like an OS or other "typical" C/L engine. They do not like a lot of prop load and a Cox product engine has more torque and will pull more prop than the Norvel .061, but won't run the same RPM. The three bladed props like were used on a lot of Cox plastic RTF models are useless on a Norvel!! It's been fun and interesting working with these things to see what they like and don't like and I'm just starting to get them figured out, I think!!
  Keep us posted on progress,
   Dan McEntee

Any suggestions or cautions? It’s a Pinto / Norvel Big Mig combo with silkspan. Nitrate underneath and butyrate top coat now. Need to fly it before making it pretty.

Thanks.

Dave Mo…

  Usually the model is painted before you fly it. Good luck getting any paint to stick if you do go ahead with flying it before finishing it.

Paint?  Who needs paint?

Some good thoughts here. My .061 Big Mig is stock (i.e., BBTU) and hope to leave it that way. Will put the pinch on an APC 5.5 x 2.5, Dan, in order to keep the R’s up.

So I have come to agree with youse guys who discourage painting after flight. The real problem then is the minuscule fuel tank. Bench runs seem to eat up way too much juice. Think I’ll solder up another tank about double size and then enlarge the fuselage front to accommodate it. I’ve heard these Pintos can run tail heavy anyway.

Thanks all.

Dave Mo…

   I finally got a chance to fly my Doodlebog/.061 combo this week a couple of times to continue my development process. My engine set up is the same, at stock plug with one (I think) head gasket, APC 5.5 X 2.5 and I went from 45 ft lines to 47. This let me up the RPM to the 20,000 to 21,000 rpm range and if needed I think it will go more, but I'm still around 4.5 sec lap time and would like to get closer to 5 sec just for my comfort. I went to a standard vent set up on the tank and tried muffler pressure again. I'm liking this arrangement so far. It never ran this good on pressure before , but I wasn't getting close to 20,000 rpm before either. At this needle setting I'm running over 8 minutes on 10& nitro fuel SIG Champion mix if 50/50 Klotz and castor at 20% total oil. Tank capacity is approximately 1.5 ounces and now I can short tank it a bit. Next flying session will be with 1 1/4 ounces. If I were you, I would test fly the tank you have, just to get a good base line on what the performance is, and you can adjust from there. If you are at 1 0nce capacity now, 2 ounces will not be necessary. Keep running the engine on the bench or in the air , as I think both the piston/cylinder fit and the crank shaft/main bearing fit need a fair amount of run in, and your mileage will get better.  I got feed back from several guys that only use 10% nitro also. 15% if it's really hot or higher in altitude. You just have to figure these things out, run them the way they need to be run. It's like I learned running four strokes. Forget everything else that you know about running model engines!!  These are a different animal!
  Type at you later,
  Dan  McEntee

if you fly it and don't like it the paint job might suffer. If you paint it first at least you'll like it for a good paint job.

if you fly it and don't like it the paint job might suffer. If you paint it first at least you'll like it for a good paint job.

If you fly it and don't like it then you can fix it and like it.  A good finish will take as long as building the plane. There is a very simple way to keep glow fuel off of the plane - don't use any!  I have never done this but you could iron on some SLC over the place exhaust hides.  Who knows, that slightly heavy jewel might just be a winner with MonoKote or end up Mrs Piggie if you loaded on the glassy finish.

Ken