bluehrnt

Did you find the specs on the OS engine with the larger prop on their website or do you have some cool contraption in your shop? Thanks for the info. I am kind of slow when it comes to specs so simple things like a bigger prop never entered my mind as a serious fix. I suppose i should measure to make sure it wont drag on the ground.

Thanks again

Cybertom

The OS engine specifications are available on their website. Once I had the specs I simply entered them into my ThrustHP calculator. This FREE and excellent little program will tell you how much static thrust an engine will make at a particular RPM with a particular prop. It's pretty darn accurate. More than accurate enough to make purchasing or design decisions.

As far as dragging on the ground I'm running a 24x12 Zinger on my 1/4th Flair PT-17 Stearman and It has plenty of ground clearance. I have posted these links to videos of my Stearman in other threads. I will add them here so you can easily see how BIG a 24x12 prop is on a 1/4h scale Bipe. I don't think you will have any problems with a 22 inch prop on a 1/4th WACO.

The links below no longer work -Moderator...
[link=http://www.cmac.org/phot/videos/pt17_stearman/PT17_1stFlight.wmv]PT-17 1st Flight Video[/link]

[link=http://www.cmac.org/phot/videos/pt17_stearman/BigPlaneFly.wmv]PT-17 BIG Plane Fly-in Video[/link]

Meesh

My Feedback: (135)

Henry,

I'm fllying an Aeroworks Stearman (77" span) that weighs 21 lbs with a Saito 325 5 cylinder and it has plenty of power. The Magnum 400 Radial has a little more power than the Saito and should work fine. You can get it from www.bonparhobby.com in Canada for about $859.00 (US$). I had one and it was very nice looking but sold it before I ran it.

Bob

chasrb

I just received my Microsens Glow7 onboard glow today, what a nice piece of workmanship! It has the leads all cut and set for the ST710 so all I have to do is connect them to the glow plugs, receiver adn battery and I am good to go! That is the good part, the bad part is I will not be using the well crafted glow driver wire set that was shipped with the engine.

chasrb

I have a question on the intake on the Seidel or any radial with the carb behind the cowl. If I build the scale intake for my stearman and have it connected to the carb, will it draw enough air to adequately supply the engine? I think it will, but was looking for other thought on it.

Cybertom

That's sounds simple but it's not that easy to get it to work. You may find that the engine runs lean or rich depending on RPM. It would probably be enough to have it shoot air in the general direction.

Remember to consider the air flow around the engine for cooling. Whatever the surface area is of your air intake is for cooling, you will need about 3-times that much for the air to flow out.

Cybertom

Chasrb,

I just watched an outstanding video of the Seidel ST770 engine running on a test stand with Seidel himself at the controls. I then saw a 20lb Nieuport 17 fly around like a bat out of hell with that engine bolted to it. It was almost ridiculous to watch.

Seidel claims that the engine can turn a 24x8 prop at 6,000 rpm. That's 33.80 pounds of static thrust according to Thrust HP. This was using straight Methanol without any Nitro and about 8% oil.

The new version of the engine you purchased is supposed to be even more powerful than the ST770. You will have no issues getting your Stearman off the ground with your new radial. That engine ROCKS!!!

If everyone wants I could make a short MPEG video of the tape I saw and get a link posted here.

chasrb

Wow, where did you see the vid? Is it available to watch? I can not wait to fire my 710 up!


On the intake issue, my initial thoughts were to build the scale intake and have it approx 1/4 to 1/2 inch away from the intake of the carb. I agree after more thought that the engine may not be as "tunable" if there were an attached carb intake. I can only experiment and then report.

Cybertom

Another RCUniverse member sent it to me on VHS tape.

PS,
I have the day off tomorrow and I am shipping out your stuff.

chasrb

Thanks for the decals.

Do you have a way to transfer the vid so we can all see it?

I mic'd the prop shaft on the 710 and used a thread gage on it. It is 10mmx 1mm. I am surprised that neither Paul or Phil have responded to my request for the prop dimensions or for the detail on the 710. I hope this is not the harbinger of support to come!

Cybertom

I will capture the video on my computer and make a short MPEG video of it. I can probably get it posted on my clubs website and then make a link to it here. This is also another member here who has my videos posted on his website. One way or the other I can get it up here. I'll see if I can capture it tonight.

chasrb

Tom, I think Martin posted a pic of a Stearman that the builder also had built the radial engine as well, I think I may have found a better picture of it so now we have the names of those folks.

Here is the pic:

Cybertom

SEIDEL RADIAL VIDEO

Here it is!!! Another member sent me a video of a Seidel ST770 engine running on a test stand started by Wolfgang Seidel himself. It flys a 17.5lb Neuport 17 like a bat out of hell! I dumped the video to my computer and created a short highlights video. Enjoy!!!

This is a link to the Corsair Model Aircraft Club website. It's one of the best out there so check it out. You can find the Seidel Radial engine video and others on the PHOTOS page:

[link=http://www.cmac.org/home/home.shtml]C.M.A.C. Corsair Model Aircraft Club[/link]


This is a link directly to the Seidel Radial Engine Video:
[link=http://www.cmac.org/phot/videos/seidel/seidel.wmv]Seidel Radial Engine Video[/link]

chasrb

Wow, I can't wait to get mine started let alone on an airframe!!! Sounds like he did not use a collector on the engine. Also he mentinoed Nick a few times, I would gues that is Nick Zirolli?

Thanks Tom !

Cybertom

No, I don't think it's Nick Ziroli. This video is to old for that. I'm guessing the video is around 10-years old.

Reg Hinnant

My Feedback: (9)

9 cyl Seidel for sale on Ebay
http://cgi.ebay.com/SEIDEL-9-CYLINDE...QQcmdZViewItem

alpal

I am new to these forums.
As I read these posts, the last was posted 7/12/2005. Am I right?
I have a 1/5th scale FW190 from Germany Sistmodellbaum. It is awsome in detail and really would merit a radial.
Try as I might, I see very few radial engines around. All the talk of Seidel motors and even Technopower ....I don't see them advertised.
Is this forum still alive?

chasrb

Alpal, the forum is just sleeping right now, getting into the last quarters of the year and too much left to do and that leaves less time for the forum and talking about the planes and engines.

The only place you will really see any radials is in the OS, Saito, RCS, Moki type lines. They will mostly be the three and five cyl setups. The 7 and 9 and even 14 and up are more boutique in nature and you will have to look for them to find them. In this forum and some others in the Radial engine thread, you will fine the names and contact numbers for the 7 and up cyl engines. Myself, I own a Seidel ST710 and it is as beautiful as it is scale in appearance. If you get one you’ll see what I mean!

Without a doubt there is sticker shock when you look at this level of engine design, but when you get down to it its on par with the Jet engines that are out. The price is worth the pride and feel you’ll get when the airframe is complete the engine is mounted up and then, the first time you flip it over as one unit and send it into the sky…Just ask Cybertom…look at the videos/links he has placed on the forum. There is nothing like it…

chasrb

Hey guys do me a favor and go to my website I am building for the Stearman and other things Radial and multi-cyl. it onlyhas one video on it but I want to have a test to see if it'll work for others. The site is [link]http://www.olivemoon.com[/link]. Yes I know not much for an airplane site, but I have had this for a long time and did nothing with it, until the Stearman kit entered my life...


Thanks

AS OF 1-1-07, THIS SITE HAS NOTHING ON IT BUT A SET-UP PAGE

Cybertom

The video works. Olive Moon?

chasrb

I know the name is a bit "different" I came up with it after watching the moon rise while staying at The Drake Hotel in Chicago and enjoyig a really good martini with olives

Thanks tom, btw what are you up to lately?

Kmot

My Feedback: (24)

That's really funny! What type engine is that on there?

chasrb

It is a horz 4 cyl probably a 3W, I have more of these wild guys I'll post later now I know the video works on the site.


Thanks

Cybertom

Busy remodeling the house so I can dedicate next year to lots of airplane stuff.

chasrb

I was going to run some thoughts by you Tom concerning the modding of the landing gear structure, but I'll do that on teh PT17 thread...