Class I Cox Vintage Speed secrets...

I have a small stack of baby bee tanks I could experiment on. This is interesting if you are willing to share.
Phil

Yes! Please continue !!!!!!!!!!

What type of glue are you using? Looks like JB weld. I haven't had any luck with JB and Nitro.

Ron

That looks like Devcon to me. We used it in the engine room for emergency repairs when I was sailing.

http://www.itw-devcon.co.uk/index.php?/devcon_mro/epoxy_maintenance_repair_and_overhaul_systems/devcon_plastic_steel_putty_a/

Yes I am also interested Paul , Thanks for sharing you secrets !! Eric

Hi Paul.. Yes.. Thank You! Definitely COOL! I like the clean bends in your hard-tubes. Do you use something to support the inside of the tube(s) while bending? I have a set of the K & S "spring-coil type" (external) benders.. but for such a short length tube, I'm not sure how well they'd work.. or how tight a radius could be formed.

Hi Ron,

Five minute J-B Weld failed initially, but the current vent appears to be holding (so far) using 24 hr. J-B Weld Epoxy glue...

Cribbs74 wrote:What type of glue are you using? Looks like JB weld. I haven't had any luck with JB and Nitro. Ron

Hi Roger,

I use the fine Harry Higley tool to do all my bends using (soft) K&S tubing as shown in photos.





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roddie wrote:Hi Paul.. Yes.. Thank You! Definitely COOL! I like the clean bends in your hard-tubes.

OK guys, thanks for the kind words. Here is a bit more info on the making of my "Super Babe Bee".

Regarding the tank bowl, if you are using the G-Clip type reed retainer, it is wise to file or Dremel grind a small 'relief' at the top. This is done because some pistons (especially when loose in the ball-socket joint), will hammer away at the tank. This creates shed metal particles & worse slows down the engine. A relief here, ends the problem.
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2. With the previously described uniflow tank venting, I was able to drill out the tank venturi & backplate to .093". This size usually causes erratic running with the stock tank. I sneak up on the size using one size smaller drill bit so that the final cut is only a few thou. I'm hoping the final hole bore finish will be smoother than with just a single drill bit bored hole.
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3. Of course I prefer a hard anodized crankcase coupled with a Killer Bee crank. Although I use a true turning 'after-market' spinner, but the 'Original' Cox vintage spinner is your best bet in that department, for a smooth running high speed spinner. Some after-market spinners wobble a bit at high RPM, so keep an eye out for that.
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4. Of course, I will NEVER recommend grinding away in the cylinder ports, I will concede that the grinding shown here has not slowed anything down...


5. This particular engine seems to run very well with only two (.005) head shims. Since it's a speed engine rather than a racing engine, the occasional blown plug is acceptable. I would have like to have tried the Nelson/Galbreath head except that it may not be allowed under the "Vintage Class" rules, especially when the original Cox plugs are easily available.
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6. Most people don't realize that a speed model is only as good as its PROP! I started out with an APC 4.5D X 4P prop. I'm thinking that I need more pitch & so have modified a number of other higher pitched props. At this level, with nobody to compare notes with, it's all a matter of cut & try. Flight testing is something I do not have the luxury to do. So, we'll see how they work out at the next contest!
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This British Class I Vintage Speed project has been FUN! Other than props, I didn't have to really buy anything new & it certainly doesn't break the bank. I hope you find this of some interest & value.

Cheers, Paul a.k.a. Mr. Mouse

Superb post Paul.

I have used the high strength J&B weld for several years on many different small and large engines. With proper prep (scratched up and thoroughly de-greased) I never have had a failure of the stuff.

One question...looks like the metal tank back plate could be hogged out some; removing flash, nubs, and such to increase the total volume of fuel.

Is this prohibited or not desirable for your speed engines?

Hi Fred,
Thanks for the kind words. Removing the tanks inside flashing, nubs, etc. is useful for AMA Class I Mouse race, to increase range. I heard it could be worth another 2 laps, but can't substantiate that claim as I don't do it. I have managed to get in 33+ laps with the 8cc tank in AMA mouse race, if things are set right. With a wrong setting I'm often short on range & therefore such a mod could help. Initially, I was marginal in getting enough laps with the standard 4cc Babe Bee tank. I suspected perhaps due to fuel siphoning in flight. This appears to be true, as the uniflow tank now has lots of range even at a higher speed. When I mean lots, maybe that's a mis-nomer. I need to take off then get 12 timed laps on 35' lines for Vintage Speed. No problem at all now. Racing nor speed have any restrictions on modifications to the tank.

Cheers, Paul

fredvon4 wrote:Superb post Paul. One question...looks like the metal tank back plate could be hogged out some; removing flash, nubs, and such to increase the total volume of fuel. Is this prohibited or not desirable for your speed engines?

Thank you Paul.

This is excelent information.

Thank you for sharing with us. You are the expert!!

Theo

Hi Paul , Thanks for sharing the good stuff from experience , Where you opened up that cyl. porting was that a TD cly ? and is that possibly why you said you were fouling plugs could be from over fueling while running ?Just curious I know you know what ur doing to get those numbers and be the winner you are . Thanks Eric

Paul,

Thanks for leveling the playing field

The tips you provided apart from your guide sheet is what I was doing the last couple years for the tach race.

Are you going to compete this year?

Ron

Hi Eric,
You're very observant. Yes, that was a TeeDee cylinder I opened up the ports on. The glow plugs don't foul unless they're ingesting metal from somewhere. The plug elements can get mashed up & deformed from severe running conditions though, if that's what you mean?
Cheers, Paul

getback wrote:Hi Paul , Thanks for sharing the good stuff from experience , Where you opened up that cyl. porting was that a TD cly ? and is that possibly why you said you were fouling plugs could be from over fueling while running ?Just curious I know you know what ur doing to get those numbers and be the winner you are . Thanks Eric

Hi Ron,  I'm considering... Cheers, Paul

Cribbs74 wrote: Paul, Thanks for leveling the playing field Are you going to compete this year? Ron

Hope you do!