jsesere

My Feedback: (38)

http://www.ebay.com/itm/Rare-custom-...item3a973923a5

Pond Skipper

Yea this is the one your selling why?
Item location:
Salem, Oregon, United States

jsesere

My Feedback: (38)

I need the $$$.

Pond Skipper

Understand, I have placed a bid 4 times still under someones max... should sell well.
I bet it hits 100+

Mr Cox

Why don't you just write that it is you who are selling it, straight away...?

aspeed

Then it wouldn't be a secret, would it? I remember when you could get the blank cylinders, a guy was making piped ones by brazing some tubing on the back where the exh. exits. I should have got a few, they needed honing after the ports were put in, as they were a bit undersized. I wonder if Bernie has any blank ones around?

Pond Skipper

There is a way to block one of the exhaust ports buy the double vented slit type cylinder plug the slits on one end with JB weld and cut out the slit on the other port side.
The thin slits should / may hold the JB weld. Degrease the cylinder / tape up the inside and press in the JB.
Perhaps a spring steel C clip wide enough to block the vents and snap around the cylinder. Could tap in some aluminum sheet stock and file smooth inside and out.

Mr Cox

What would that accomplish?

I assume that the custom single exhaust ones have a schneurle like design to the transfer channels and/or angled transfer ports like the .15 engine?

Pond Skipper

I have a MK II with three schnurle type transfer ports circlip type.

I have some old single port dual exhausts 1/2A cylinders could be used for a pipe just a matter of what you're willing to work with and do to make it happen. The only reason I would want a single exhaust is to retrofit a tuned pipe for the fun of use / sound and less goo on the plane.

aspeed

The piped schnurle one I was familiar with did go much better, but did not last long because of the high revs and heat. There was nothing else available then so you did what you could. The Norvel and BB CS came out shortly after that. I have thought of changing one too, but there is better stuff out now. For $30 I could get another AP .09 to carve up, and it already goes better than the TD .09 as an example. It is BB, ABC, throttled and muffled too if you need it. I made up an adapter for a pipe too. I see we are brainstorming at the same time.

Pond Skipper

Funny you should mention an .09.

A Medallion 09 cylinder showed up in the mail monday new old stock I had bought cheap as it only has one large transfer port / no boost flutes - but is a thick walled none SPI. Looking at it now best plan is to plug one exhaust port with a chunk of slightly over sized soft block of shaped aluminum to tap it in and hold in place with a 1/4in wide spring steel U shape clip with holes / bit of thick wall tube moon shaped to butt up flush to the cylinder wall and a bolt thru the tab holes and tube. From there I can go with a tuned pipe or header pipe. I have ran a RC 09 with a 6x2 pylon prop it screamed the engine ran two summers on a small fast plane never a problem and the piston rod / ball socket didn't need to be reset at the end of season two.

Here's a doodle

aspeed

Looks like an interesting project. I played a bit with the AP. Made a header for a pipe. Never used it but it goes good without it already. Also made some new stingers for the original muffler which is too restrictive. There is about a 4 mm exit hole, I made one that is 6mm. It is already ball bearing and very easy to work on because of the simple cutout ports. Turbo plug head too. Oh and $30. I would likely go to a 6-5 or 6-4 at the least. You want it to go forward and a 6-2 would hold it back I think. It would sound good though if things don't break.

Pond Skipper

Nice! I have a AP .09 Hornet too lol..Mine cost 31.95 free shipping new short of a torn box from ebay.
If you look at the box it says 15k with a 7x4 but with the APC 6.3 x 4 pylon prop 30% nitro should get it singing.

Pond Skipper

Yea the TD 09 was hauling arse the plane was undersized and light all balsa engine rpm was over the top and in dives it was a show stopper for its size bolting over the runway from out of no where scary passes for those taken off guard. Mathematically I still don't understand how it was so fast on a 2p.

Any ideas with the mods what sort of RPM you are getting?

Pond Skipper

Found this from you:

F2D combat prop. It measured 6.2" x 5" pitch on my guage, and said Alex on it. (recall this rpm)?
I think the 7-4 MA prop was around 16,900

A pre grad mech engineering students did a paper on this engine full analysis.

http://www.me.umn.edu/~wkdurfee/publ...0SETC-0095.pdf

Note at 154g / 5.434 oz this sucker is a porker in relation to the TD .09 RC at 3.92oz
The AP .09 sleeve is thick at 3mm its a .15 in size engine. You did good to open the sleeve up for better flow.
MyTD 15 with prop and throttle sleeve 154g / 5.43oz

They found peak power during dyno tests at 10.5k aprox 100w.( nitro use % unknown)

Mr Cox

Wow, that's a really great testreport!
I'm really surprised by the results though, maximum power around 10500rpm and no point in going over 12000rpm, that just doesn't sound right for a modern ABC engine.
Perhaps they used the stock muffler or something, but it does show what you get compared to what the manufacturer promises in their performance data...

aspeed

Sorry for getting off topic. Just looking at my notes here. The AP .09 15,200 rpm on a 7-4 MA 10% fuel. No muffler 16,900 and an opened up muffler 16,100. With the new head I made, it went 18,200 the way it came off the lathe, without further experimenting. I tried a 7-5 prop to compare to the similar AP .15 and it was 12,800 with no muffler. For a comparison, my LA .10 was 17,500 with no muffler, and the TD .09 was 16,400 with no muffler, so they are quite similar. I did not cut the slots in the cyl, that is stock. The .15 is similar, but they are machined right through. The .15 is really just a bored out .09 and the sleeve is thinner, so they just machined all the material. There are no ports to match up on the casting, kind of a bonus I think. I use my .15 as a control line platform, so the idle isn't important. I don't think they idle real well. Great cheap motors for thrashing around though. I crash full speed upside down and just laugh, brush the dirt off, and go again. I haven't used the .09 yet, just on the test stand. I don't think I would rev it much over 20,000 rpm as I did with the .15 because the big rod end got pretty sloppy on a short 25,000 run with the combat prop. The piston was heavier, which may have made a difference in wear.

Jim Thomerson

The 1/2A CL speed guys made schnuerle ported engines out of blank TD 049 Cylinders. The late Gene Hemple showed me some. He also had the piped engine with which at one time he held the 1/2A CL speed record. I have a Zaic yearbook which has a TD 049 with a Spacehopper reed backplate added. A Babe Bee crankcase was modified to fit over the cylinder and provide pipe attachment.

Pond Skipper

Thank you Jim = )

Link:
http://www.rcuniverse.com/forum/1-2-...eed-speed.html

Post 99 / 4-4.75" prop.

35% nitro
The first run had the engine running at about 25.3K rpms and was recorded after a heavy dive, smoothly leveling out before the beginning of our runway. The file showed that the airplane was flying at 114 mph!!!!!!.
I then ran the second through. This run was admittedly recorded while the airplane was diving (shallow) at the recorder instead of level flight. The engine was turning just over 26k, and the recorded speed was 121mph ......

Half A Tuned Pipe




FYI

http://www.thebuildingboard.com/2011_05_01_archive.html

aspeed

The motor I was talking about may have come from the pile that Gene Hemple had. It likely held the record here in Canada for a while in 1/2A control line speed. I believe it was over 100 mph. I know we were making pipes. I think his was brass shim stock and I tried one out of aluminum unsuccessfully. I just came across it about a month ago. The rules for line size and length have changed, so the records would not apply any more. I had a couple too in the 1/2A speed and Proto. Now there is just profile proto.

Jim Thomerson

The TD 15 was prone to the cylinder breaking at the exhaust ports and was soon replaced by the "Mark I" 15 which had a thicker liner.

Pond Skipper

Thats true Jim they also redid the TD .15 with a thickwall cylinder

Here is mine: very rare with a throttle sleeve 2.5mm and cylinder about 5mm I have the Mark II its the same thickness.

Pond Skipper

I had to find a way to throttle the MK II so used this cox slide exhaust

vertical grimmace

My Feedback: (1)

Once I got my TD's close to 24,000, they did not last long. Seemed to be happiest around 22,000. I still have a couple I sed for CL combat. Fun little engines!

Pond Skipper

yes power to weight, small in size and brings back memories all the good ones at least lol..