Looks like I'm just dumb. Randy lists props on his website. Sorry guys.

Ok, i did the search thing, and im confident enough in the prop size. Randy Smith has been helping me via email in the pipe and header.
So my question is... Is it a bad idea to use a xoar or mejzlik prop? The props that everyone mentions sound great, but i don't know where to get them. I'm shooting for competing in advanced this season, so i probably couldn't tell the difference in prop types anyway. And i like wood props, is that a good idea to use a quality wood prop?

   I am pretty sure you would be able to tell! Presuming you have the same setup I run, you want a 12.5" 3-blade, and then adjust the pitch to get about 5.3 second laps with a launch RPM of about 10,000. It should 4-stroke throughout the flight under normal circumstances. For me, that's 3.75".

    Brett

Oh, and Steve. Yes a pipe. Randy is hooking it up! Told me what i need and he's got it in stock.

  Hi Dane ,
  What I recommend is set yours up as close to Brett's as you are able , his seem to work as well as any I've seen.  I'd say that plane will put quite a demand on the engine  . Good luck locating the proper propeller.
  John L.

Eliminator Props in the Vendor's section sells  copies of the Bolly 12 and 13" 4.24 pitch CF props. That would be a good place to start. 

Lol, i just emailed Steve H last night, "why didn't i think of that?". My last batch of 1/2A speed props came from Steve Wilk. Thanks for the reply

Thanks John. Steve H emailed me the articles last night. Also, i checked out the post from Brett's nats set up. I'll just be copying that.... Thanks Brett!

  Note that I have used a late Randy/Billy pipe on mine from the start, just like on my PA. Get the current model closest to the 51-60 "Slimline" pipe. Randy knows which one I am talking about.

     Brett

Just as an update, i got the pipe and header. I'll take the header into the shop tomorrow. I'll need to modify it slightly. The engine is rectangular in the mount area, this header is a diamond. I'll just square it off a little. I'll do it there in case i go too far and need to tig weld the joint again. I believe there's plenty of room to take off material.

Anyway, i want to get on this thing and get it in the air. It's actually really nice weather here.

Ok, opportunity for solution number 1:
The header is actually a significant difference in size. I would need to machine off a lot of material, and weld the left over gaps. Or, easier option is to make an aluminum spacer plate. Are there any engineering or metallurgical oppositions to a spacer plate?

Dane  The ones I have seen came with spacer plates, that is why I told you the short 1/2 inch  bolts  would not work

Randy

Oh, great. I guess i know see exactly what you're talking about. Then this is a very easy fix. I'll make a 3/16 spacer to clear the fins. That will be solved tomorrow. Thanks again Randy. This is going to be great

     Note that the screws are 5-40's, not 4-40's. 4-40's will thread in OK but strip out when you try to tighten it.

     The stub exhaust normally comes with it. Its 1/4" thick, about .518 x 1.21. Flatten and clean both mating surface, flatten and clean the facing part of the header, and clean the mating face on the engine. Then assemble it with Permatex "Ultra Copper" silicone (or the similar red high-temp silicone from 3M) and *nothing else*. DO NOT, repeat, DO NOT, use any separate gasket material of any type.

     Use a spigot in the #5 venturi, carefully counterboring the dribble hole for the head of the smallest SIG eyelet (1/16 OD of the barrel of the eyelet). Push it in until it sticks out about .025-.032" from the surface. Use a panty hose diffuser on the inlet.

    Brett

    Note that the screws are 5-40's, not 4-40's. 4-40's will thread in OK but strip out when you try to tighten it.

     The stub exhaust normally comes with it. Its 1/4" thick, about .518 x 1.21. Flatten and clean both mating surface, flatten and clean the facing part of the header, and clean the mating face on the engine. Then assemble it with Permatex "Ultra Copper" silicone (or the similar red high-temp silicone from 3M) and *nothing else*. DO NOT, repeat, DO NOT, use any separate gasket material of any type.

     Use a spigot in the #5 venturi, carefully counterboring the dribble hole for the head of the smallest SIG eyelet (1/16 OD of the barrel of the eyelet). Push it in until it sticks out about .025-.032" from the surface. Use a panty hose diffuser on the inlet.

    Brett

Thanks for the info Brett. Thanks especially for the measurements. That's pretty easy to copy. I'll check what's on the spigot situation. Rumor has it, this engine was flown in the nats already. It might have a good set up. I bought it sans header and prop nut

Ok, so with a little luck, i got the spacer made. I was have mucho problems with my "mill" set up. The chuck kept falling off everytime i advanced the table forward! Whatever, i got it. I'm measuring a 5-40 × 7/8 exhaust bolt. Does that sound about right?
Brett, did i pm you? My phone sometimes skips the send portion of pm's

Ok, so with a little luck, i got the spacer made. I was have mucho problems with my "mill" set up. The chuck kept falling off everytime i advanced the table forward! Whatever, i got it. I'm measuring a 5-40 × 7/8 exhaust bolt. Does that sound about right?
Brett, did i pm you? My phone sometimes skips the send portion of pm's

Dane
just screw in a 540 to both holes in the case, see how far it goes in, take that measurement, add the thickness of the spacer and header block, the subtract 1/16 inch
you may need  to trim a 1 inch bolt, or maybe not??

Randy

Why don't you call Dub Jett and get the right part and the right screws?

Just asking,

Tim

Is there an RPM i should be shooting for on the ground? Or is it an experiment with your set up kinda situation?

I don't have a RO-Jett .61, but I'd suggest setting the pipe length at whatever Randy's chart suggests for the exhaust timing it has...which I believe is up around 145*.  Then, I'd borrow a CF prop or two from your locals and start launching at 10k to 10.5k.  Using a prop you can't replace or isn't potentially the best prop for the combo isn't very productive, IMO.

Always get a reading on launch rpm every flight, so you know where to go from there. Be sure the engine is fully warmed up, because if it isn't, you don't really have a baseline. The engine will lean out as it heats up...about the time you get the handle strapped on. Don't run the pipe shorter than suggested...tends to burn down the engine, I think. I've heard PW say that a couple times, not speaking to me, however. Brian Eather makes really nice stunt props, and is pretty quick to get them to your door.

Email Brett if you need good prop advise. I would guess wrong, no doubt, but I've had very good results on the .46VF and PA .51 with the 12 x 3.75 undercambered 3 bladers (full 12" for the .51, 11.5" for the VF), so I'd probably try a 13" version and pitch it to 4" and maybe pitch up the last 2" to 4.5" or so. My experience indicates that the U/C props work better on overweight models...or maybe for overweight pilots?  YMMV~  Steve

Ok, i was lean, and it broke early in every maneuver. I really am taking this advice and applying it. I don't have the correct props, i just wanted to fly today. I'm gonna fly again in the morning. I'll change the prop and tach it before flight.

Steve, you are spot on about inquiring on pipe length. Randy and i had many conversations about that stuff. I started at 18.75 inches length

Whoops, just caught that. Typo.
Thanks Randy

According to the charts, i would be in the 18.5 - 19.5 range, right?

 Please set it up per this post:

http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=232053&mesg_id=232053

    with the suggestions above. This is not an experiment or a new development, this setup is far and away the best stunt engine I have ever run or tried and has proven absolutely bulletproof over the last 13 years or so. The only issue is to get a prop that works with this system, but given the desired 10,000 rpm launch revs, the fact that it runs in a 4 stroke all the time, and has to fly at 5.25-5.4 laps, that should narrow it down to ONLY the prop. 5" appears to be *far* too much pitch. I am running 3.75" and the same system will work with 3.6 to 4.2 depending on the air density. 3.75 to 3.9 is the middle of the range. The second airplane flew better with 3.9, the current airplane does better with 3.75, even on hot days in Muncie.

   The pipe length should be 17.5".

    Brett

   

Hi Dane

to follow  Brett's suggestion, you will need to get the same Eather props, or clones, or it will not work, if you run more pitch as you stated you will need to run a longer pipe length, as I suggested, if not it will not be running and getting the pipe benefits, so first thing is you should try to get props, and a pitch gauge, I hope you have someone close who can help with the pitching of the props
let me know if you need help with anything

Randy

   It will work with other props.  What you need to find a prop with similar load characteristics that provides the necessary speed, which is why you start with a known proven system and adjust the prop around it, not go off on a tangent with speculative systems.

     Brett

  

to follow  Brett's suggestion, you will need to get the same Eather props, or clones, "

hence the reason, i wrote the above  in my post , he will need props that he can work pitch on, that are very similar to the ones you use

The yellow mark is the first baffle  measure from there to the glow plug

Randy

Ok, i got the pipe length set to 17.5". I read through Brett's article. I believe I'm set up the same. As long as i can prop it to get the same load and speed i should be done ! I'm heading out to the field now. I have my tach with me this time!

what pitch are you using now?  try one with about 1/2 pitch less.
Also are you in a 4 cycle at that speed? or a 2 cycle?
You should try the setup launching the plane in the fastest 4 cycle it will run in on the ground, this should be a solid 4 in the air, check laptimes  then

Randy

I'd like to see you trying a 12-4 or 13-4 APC as an interim sort of deal. I haven't laid hands on the 13-4, but I believe it's a much wider blade. Don't automatically think the "dagger" 12-4 won't work for stunt...they do work on some engines. Apparently, blade area isn't as important as once believed. Steve

Hey Pete! I believe what you're talking about has been covered. The way the engine and pipe are set up now, the engine runs great. My airspeed is just too fast. I will attribute this to me setting everything up according to Bretts SSW post, except the correct prop. If I'm going to set it up the way he did, i also have to use his prop. Which, by the way, has been ordered and will be taken care of.

Steve, i like what your saying. I really need to practise with a plane i know works well before this contest on the 24th-25th. The fact that i have to order props and wait puts this plane out for me. I'll get it going for the next one though. As soon as props come in, I'll update you and let you know what's up.
 Also, I'm thinking I'll just have to order that pitch gauge from the UK i told you about. Puts me farther out on this project