Tim Wiltse-RCU

Not many people know that Cox made some .09 or .15's with "normal"wrist pin piston/rods. If I remember right it was one of the larger Madallions.

LAter,
Tim

D Bronk

So many Men ,all in a BOX....Ya`all need to think outside the box.. ..I just boyught some things from Select hobbies.One item is an 0.020" cylinder with exhaust throttle,,that piston,slides,right thru the cylinder.I heard some of the Surestarts have been like that too.I`m guessing there`s no taper on those sets form that to happen..Here`s a "new Box"to think about..Check the Pics ..This works , real SLICK Man..I had to ask Larry D. how it came apart .I never seen a rod and piston put together like this before either.I would say this set-u would not be that hard to make ,and no retainer Clips or Grooves to Cut .Nothing to hang up in the transfer ports ,no matter, where they are located[8D].

Tim Wiltse-RCU

Dave,

The VA's piston is like that too I believe.

Later,
Tim

D Bronk

I think, it`s a nifty little set-up.

Larry Driskill

Yes, it is a pretty niffty setup, but tends to not allow enough/as much oil to reach the pin.

On some VAs I cut a small channel vertically thru the carrier threads up to the pin to try and allow a bit better lubrication.

Rick W

My Feedback: (20)

Larry,

Do you have a picture of the VA piston and rod that you could post. Also what would be the best material to use for the piston and retainer with a cox cylinder. This is something I could find time to do on a weekend.

DBRONK, Thanks for the pictures, now that I'm out of the box I can see clearly....

Thanks,

Rick

rainedave

My Feedback: (1)

I'm a little unclear about that setup. Could you put a shim inside the piston to cause the retainer to not screw in as far, thus increasing the stroke/compression? Or would that completely throw off the port/piston timing?

combatpigg

My Feedback: (3)

Very astute and observant, RD.[8D] Yes. You CAN change the compression that way. The other way to change the compression is to forget to tighten the carrier/piston threads, [maybe drip on some Loktite to keep things where they belong]. This is a nifty arrangement, but heavier than a swaged wrist pin. Credit for this idea probably goes to my neighbor down the road, Dirty Dan Rutherford [the original designer of the VA]. You wanna talk about outside of the box, talk to Dan ?

Larry Driskill

Yep Pigg, I'll bet you are correct as Dan's MKI VA had the arrangement and it migrated to the MKII.

Did Dan ever even acknowledge that there are boxes? Too bad he has gone over the the white shoe, highly refined CL Stunt crowd and doesn't grace us much anymore.

D Bronk

..Your Welcome Rick,.Good thing, it was only a little Box,and not ,a fenced in Cage ..There`s too many good Men, around here ,that will try to help you escape.. ..Rick, I posted a solution, to your Piston Material,in a Thread ,that Larry just Started.It`s called,
??something?? Rick..LOL

..CP.Does your neighbour, visit here at all??Sounds like, he would be good to chat with too.

ptulmer

My Feedback: (5)

I'm betting Tim is planning on letting someone else do the work and he pays per piece. It's a big decision to invest in a pile of parts and he wants feedback about what would sell in our tiny little niche. Well, Tim, here's my thoughts:

Drum rotor conversions that require that I only provide a surestart...[sm=thumbs_up.gif] Less than twenty bucks...[sm=thumbs_up.gif] More than forty...[sm=thumbs_down.gif]

Small 1" or 1 1/4" aluminum spinners less than twenty bucks [sm=thumbs_up.gif], More than twenty [sm=thumbs_down.gif]

Turbo (or Nelson heads), well there's one already available for the Nelsons, so price is set at ten bucks or less. Can you make one better than the Galbreath? One that's easier to remove or lighter? If so, yes!

.02 Engine? If it's a DR or conversion like planned for the .049, sure. Matter-of-fact, a DR conversion for the PeeWee might even sell like hotcakes!


Please note that I'm talking about marketability, not what's behind the scenes. Just what I'd expect as a consumer. Opinions will surely differ.

D Bronk

..Oh,if that`s the case!! If he wants me, to buy some stuff,and I would .Then, I want ENGINE Kits, that I put together myself..Sizes Ranging from 0.010" ,to 0.074".They should be High Quality parts.Copies of Norvels/AME Cross Breed? Foras?Miniature Nelson, or Jett.Ceramic coated Cylinders ,Tefloned Pistons.They have to be priced,well,lets just say, I don`t mind paying accordingly, for what I get..A Nice price/deal, for the whole familyof kits at the same time of purchase(0.010",0.020",0.049",0.061"+an 0.074"{Family})..Oh and don`t forget my, inline twin ,I mentioned earlier in the thread,Tim..These engines ,Must have a throttle,and use,common turbo plugs,that can be had everywhere..Lastly, I want these for Christmas time.Get Cracking ,I need to buy myself a Christmas Present.Okay, 1 more thing,A top quality line of Propellors,including some Weirdo sizes, so we don`t have to ,"Butcher" props anymore, just to find something that works..

KidEpoxy

Inline Twin made from Surestarts?
Would be nice to get a DoubleThrow Crank & Rods for the surestart bashers, to side draft intake inline twins with the reeds replaced by some rotor between the cases.... so many degrees of front ported intake, closed a bit, so many degrees of rearward intake, closed a bit.

Or a Case Tapping service, to get the 2-56 corner holes done thru for folks without mills/drillpresses that want to mount stuff to the front of the case... you know, altenator / waterpump / blower / smog air injector ... or maybe a gear drive.

Tim Wiltse-RCU

Well guys as most of you know I already own a small lathe and milling machine. I am looking hard at options for a CNC mill most likely just 3 axis for now maybe 4 axis...just not sure. I have lots of irons on the fire and just wanted to see what you other consumers are needing or wanting. For what it's worth I hope/plan to have a usable DR(drum this time) conversion for the Sure Start or any of the Cox .049 reedies in the next couple of months or less. The only "catch" so far is that the user will need to file/grind/mill a few thou of an inch off the rod. I just don't know how that would work out for everyone. Other than that it will be a straight up bolt on and run. Maybe another option would be to have people send me their engines and I do the 5 minutes worth of work here in my shop. Well that project is first on my list.

LAter,
Tim

D Bronk

Need a test subject?I`ve got a new, never ran ,Sure Start.Send the part, and instructions, and, I`ll follow them to the letter ,we`ll see how a Consumer install goes..Send 2 of them ,and, I`ll convert a tanked Babe Bee too.All in the Name of research, and ,to make the world a better place,of Course..

ptulmer

My Feedback: (5)

Tim, if you can show it being done with average shop tools, that should be more than enough. If you can show it done with a dremel, Cox could sell more surestarts.

Tim Wiltse-RCU

Here is a look at the bare backplate minus carb and drum.

LAter,
Tim

skaliwag

My Feedback: (1)

Did the RR-1 have a longer crank pin?

Tim Wiltse-RCU

Yes and no skaliwag. It had alittle stub added to the end of the crankpin that was a smaller diameter. In a perfect world I would like to include a new crank that has a drilled pin with a pressed in stud to drive the drum for the conversion kit but drilling the pins is a major PITA!

LAter,
Tim

skaliwag

My Feedback: (1)

Yes I agrree about drilling the crank pin to put in another extention pin. I have toyed with the idea of doing it to Pee Wee's.

D Bronk

....OHHHhhhhhh!!![X(] That`s Purdy..I`ll buy, serial #1,+#2.. Got more Pics ,of ,The Set-up and how it works????I promise ,Not to put it into production..

Tim Wiltse-RCU

NEVER EVER drill your PeeWee Medic!!!!!


Later,
Tim

D Bronk

He Said, PEE-WEE,not, PEE-PEE..LOL

D Bronk

quote:

ORIGINAL: D Bronk

For the Cox engines..I would Chuck, all those Ball jointed ,Rod, and, piston Setups ,away, and make Rods ,and piston sets ,with a wristpin.You could Chop, the Castor oil content, in the Fuel, way down.Then,next project, Make a Rotary Disc (intake)Styled after a ROTAX engine ,probably an inline Twin(one in front of the other) ,with side carb, and ,side exhaust with a dual Header,and, twin Tuned pipes.





quote:

ORIGINAL: skaliwag

Dave... If you had this dream engine would you perhaps be making an R/C Model Snow Mobile?

..Here`s that Rotary valve, twin engine that I would like to see.Steve ,I`ve got a full scale R/C race sled,I operate the throttle ,with my right thumb.But it would be cool, to have something ,that, operated from a transmitter..With a prop on the engine,it would make nice power for a plane..Rotax Claimed, that this style engine, could ,produce as much as 20% more power ,than an egual displacement engine running REED Valves.Oh Yeah it has HEMI Heads Very cool ,how that is done too.I think ,the Ultra-light aircraft guys, are, useing these Rotary Valve ,Style, engines with a gear drive, to Fly there planes..A few pics ,maybe, they will Seed some more ideas.Tim ,Shrink one down ,and ,I`ll buy, Serial # 1