Author Topic: O.S. LA .40 for speed. (Read 18133 times)

john ohnimus · « **on:** October 06, 2015, 05:19:58 AM »

Any thoughts on this set up. Got the engine cheap, (got a stack of them now). Pan was $20 on the Bay, I thought it would be a good first model.

john ohnimus · « **Reply #1 on:** October 06, 2015, 05:20:41 AM »

Another pic

Dane Martin · « **Reply #2 on:** October 06, 2015, 07:23:39 AM »

That would be cool if it catches on. I've got lots of those engines!

Ken Burdick · « **Reply #3 on:** October 06, 2015, 09:36:31 AM »

You won't go real fast, but the LA will get you in the right direction. Save your pennies and get a Nelson. There are plenty of good K&B 6.5 cc sitting in drawers gathering dust that will give you a better run than the la. The NW B proto event was made around a beginners engine (LA .25) and it is a challenge to get them to run fast.
Another more exciting beginner event is F2D proto speed.
http://flyinglines.org/rules.f2dproto.html
The engines really scream and take off is more fun than you might think.

K

john ohnimus · « **Reply #4 on:** October 06, 2015, 12:48:56 PM »

Thanks for the advice Ken,

New to the whole speed thing, and I'm not sure what kind of activity there is on the East Coast, North Carolina in paticular. I have always been interested in the event and would like to ease into Speed slowly... I have been in contact with Marty (aka Speed Hippie) and he is going to make me up some bell cranks and I may have him do a tank for the big motor ship.

Tony O.

Tim Wescott · « **Reply #5 on:** October 06, 2015, 01:02:34 PM »

The LA line is (was, probably) OS's cheap sport engine. It's made to sell cheap, start easy, and last a long time. Making lots of power simply isn't on the list.

If you want power for the displacement, and you want a "cheap" off the shelf engine, an OS AX or FX engine, or one of the Magnums, is going to be far better in stock trim and probably has a lot more potential if you want to start modifying it.

Or, buy a purpose-designed engine!

C.T. Schaefer · « **Reply #6 on:** October 06, 2015, 04:45:33 PM »

Why not go with the LA. Should be a good trainer motor and you will be the first to see how fast it is. Admittedly, there are better motors (tons) but, what the heck. Do it and have fun. If you get the bug you can always upgrade!! TS

Motorman · « **Reply #7 on:** October 06, 2015, 10:28:23 PM »

When you lean out an LA engine all the way, it cooks the nickle plating off and galls the piston.

MM

john ohnimus · « **Reply #8 on:** October 07, 2015, 05:06:29 AM »

Yes I know that the LA is not a speed engine, and that it will be severely limited as to what it will do speed wise, but the whole point is to have a little fun and learn something along the way. So follow along, I accept all advice!!! I have some speed props on the way, I scored around 250+ on eBay from a former speed flier on the West Coast.

Ken Burdick · « **Reply #9 on:** October 07, 2015, 11:26:42 AM »

before we totally trash the la (I'm in line too) Sackett has been running 106 mph on a profile proto, 60 ft .024 lines on 10%.
I put mine on an F2D combat wing and ran around 110. These are not stock, but close enough to stretch the word. The LA 40 will make a good beginner engine and yes, have Marty the Fast Hippie, build you a tank. His work is beautiful.

For all you non believers, stay tuned to Flying Lines for some la 25 updates. We are slowly developing a well thought out blueprint for sluggo the motor.

Ken

john ohnimus · « **Reply #10 on:** October 08, 2015, 05:33:44 AM »

Ken,

Thanks for the support!!! I have read just about all of the articles on the Flying Lines site. Great work on the LA .25, in fact, that where I got the idea to use the LA .40. I'm sure I'm not the first, but it's what I have to mess around with. I also have a couple of .15 size pans to work on and a 1/2A pan from Cox.

Looking forward to adventures in Speed....

Tony O.

Ken Burdick · « **Reply #11 on:** October 08, 2015, 11:15:02 AM »

thanks Tony, I never know if people actually read the articles.

a suggestion if you want to learn to fly mono line. Build the slingshot or a good year ship, put one of Marty's offset external torque units on it, buy some .024 wire from MBS (60 ft long) when made up. Balance the model at 25-30% of the chord and be sure you have lots of up control. Put an LA .25 on the thing and you'll have a representative trainer that will fly around 100 mph. APC 7 x 7 will work well.

john ohnimus · « **Reply #12 on:** October 09, 2015, 04:57:35 AM »

Sure thing Ken,

I'm sure that will be a future project, I will definitely build a two line ship this winter, and I am thinking of a Perky speed plane too. One of the fellows here in Winston-Salem that I fly with has one.

Thanks again for the great articles!!

Fred Cronenwett · « **Reply #13 on:** October 09, 2015, 10:45:43 AM »

Ken,

If you are near the St Louis area we have a speed contest in the May each year, the date has not been set for 2016 due to some scheduling efforts with the FAI team. We had the entire FAI US team at our contest last year. Great opportunity to learn what the other pilots are doing

https://lafayetteesquadrillecl.wordpress.com/lafayette-esquadrille-cl/photographs/photographs-2015/speed-photographs-2015/

Fred

john ohnimus · « **Reply #14 on:** October 09, 2015, 10:55:24 AM »

Fred,

Don't know if you where aiming at Ken or me when you sent that post. I have been out to Buder Park some time ago with Ken Grasser for a Stunt Contest. I met Dan Mcentee, and Betty Fox that weekend. must have been 1996 or so. Had a great time, kinda soggy that year.

john ohnimus · « **Reply #15 on:** October 21, 2015, 01:17:40 PM »

Some progress on the engine... Cleaned off the exhaust port and need some guidance here, do I need to narrow the exhaust port opening at all?
I also made a spray nozzle (?) from a Super Tigre carb. I have my drill bit and taps on the way so hopefully I can get everything drilled up and see if this is gonna work!!

john ohnimus · « **Reply #16 on:** October 21, 2015, 01:18:16 PM »

Pic 2

john ohnimus · « **Reply #17 on:** October 24, 2015, 07:55:06 PM »

Assembled the engine and put it on a stand. Couldn't get it to run just right. Had a difficult time flipping it with a chicken stick. I now have an electric starter on the way. It did run briefly a couple of times but couldn't catch a good needle.

Dane Martin · « **Reply #18 on:** October 24, 2015, 08:24:10 PM »

Is there a way you can do a post or some pics on this thread of the clean up work you did on the head and jug? And did you just mill out the exhaust?

john ohnimus · « **Reply #19 on:** October 27, 2015, 07:09:42 AM »

Pic of tooling

john ohnimus · « **Reply #20 on:** October 27, 2015, 07:11:59 AM »

Another

john ohnimus · « **Reply #21 on:** October 27, 2015, 07:39:48 AM »

Dane,

I use pretty basic stuff here. The files were used to mill down the head and engine case. I just removed the tapered section of the fins. Enough to square the fins up hopefully saving some weight and helping out the cooling. The exhaust port was removed with the files as well. Nothing special here just took my time and worked it down. I would like to fill the front of the exhaust port just to direct all of the exhaust aft.
I used the reamer pictured to slightly enlarge the intake port and to remove the excess material at the bottom of the intake. I hope this doesn't alter the timing but allow a bigger gulp of air for the engine. (Thanks Ken).

Thanks for your interest and any comments or suggestions would be appreciated. I have an electric starter in the way and I hope to run this engine this weekend!!

Tony O

Dane Martin · « **Reply #22 on:** October 27, 2015, 07:51:29 AM »

Thats pretty sweet! Let us know how it runs. I gotta finish my SS21 plane but that looks fun and cheap enough to try!

bob whitney · « **Reply #23 on:** October 27, 2015, 09:05:14 AM »

if that is a standard OS remote ,needle you may have trouble getting a steady setting

Ken Burdick · « **Reply #24 on:** October 27, 2015, 10:19:29 AM »

what sort of tank are you running on the test stand? I'm certain that won't run on suction so a pressure tank is the ticket. If you are using a tin tank for pressure, be sure the pressure tap has a small dia , like .020. This helps when starting...lotsa.
You should be able to get a steady run no problem, if not.....then it's a problem that you must fix. The engine is basically stock except for the reaming to the venturi. If you are running pressure already and getting erratic settings, try an a.b. comparison using a venturi restrictor. You can put a better remote NVA into the engine for 10-20.00 For where you are with this engine, I would be surprised if it were the needle valve. Bob is right in that it's not the best, but you should be able to get a decent test run with it on a stock engine.

K

john ohnimus · « **Reply #25 on:** October 27, 2015, 01:47:24 PM »

The fuel tank sets about an inch or so above the needle on my test stand. And generally speaking for most engines .40 and larger there is no problems with this setup. How ever I have noticed that the smaller the engine the more sensitive it is on the needle with this tank. I have positive fuel flow and I am using a venturi that I fabbed up with a .187 hole. I will fool with it again this weekend and will try a tiger needle in it as well. I also have a K&B remote needle I may try.

Thanks again for all of the advice!!

Tony O

Ken Burdick · « **Reply #26 on:** October 27, 2015, 04:45:18 PM »

with .187 venturi, it should be a very steady run.

john ohnimus · « **Reply #27 on:** October 27, 2015, 05:01:28 PM »

Ken,

I should have the time to mess with it this weekend Ken. And give some details rpm and such. I have quite the collection of props now I managed to purchase around 300+ from a person off of eBay that belonged to the late Bill Nusz. I have some 7-10.5 Top Flite speed props and thought I might try to run it with one. Am I close or way out on the size?

Tony O

C.T. Schaefer · « **Reply #28 on:** October 28, 2015, 05:37:16 PM »

Hmmm, Interesting thread. First my comments: Please put a pressure fitting in the back plate and ditch the venturi. It will eliminate many problems for when you fly the plane and you will also learn much more about your motor that way. Next: Some info that may or may not be useful. I have been working with the Fox .35 and .36x motors. Myself and my pal Al have found that the APC 8x8 is a very good universal type prop for these motors. Not only do they work great, they are cheap, available and results are repeatable. They also make an 8x9. You will find that, for the most part, wood props are individuals. A number of years ago during my pylon racing phase I would buy a bag of Rev Up Props and run them all on the bench. Between all 12 props there was over 1000 rpm difference and this was typical. Just so you know. Using the APC 8x8 and running 10n x 29 castor fuel, the Fox .35 turns 14.4 on suction and the 36x 16.8 wide open on pressure. I hope some of this is useful to you.. TS

PS I attended the big Winston- Salem meet 3 times. Had a blast. Flew Formula .40 and other events.

john ohnimus · « **Reply #29 on:** October 29, 2015, 10:13:55 AM »

Thank you Mr. Schaefer for the comments and the advice.

I believe that a pressurized fuel system is the way to go, I am not sure where to install the pressure tap though. The venturi is installed for testing purposes until I get this combo dialed in. I do have some APC props in the lot of props I have, I will check and see if any are 8 x 8

Ken,

I have switched needle valves out and the K&B needle is now installed, had to fab up a bracket to make that work. Got my electric starter yesterday and should be ready for this weekend. See Pic's

john ohnimus · « **Reply #30 on:** October 29, 2015, 10:15:00 AM »

Pic #2

john ohnimus · « **Reply #31 on:** October 29, 2015, 10:15:50 AM »

Pic #3

Ken,

You can see the tank in this pic.. It is epoxied in place. I do have a plan to remove it. Any suggestions on a tank for this ride? Or send the measurements to Marty and have him make me up a pressure tank?

Tony O

Ken Burdick · « **Reply #32 on:** October 29, 2015, 11:41:28 AM »

Hey....things are looking good!
I would leave the tank as is until you fly it. When you get to it, try making a coffin tank that can be found many places and seems to me Bill W made a sizing chart that you should be able to get from Speed Times. It also has stab lock dollies that are very worthwhile building. The tank you made looks good. I built one similar to it for a D ship and it ran steady in the high 190's .....nitro days. If you can, ask Marty to sell you a tank....it will be perfect but no extra fuel so you start and go.
I use RTV for glue if the tank really needs to be secured that-a-way.....much-o easier-o to get out.
I agree with the above and start out with an APC 8x8 or around that size.
Your project looks pretty nice and you are approaching it systematically ....right on!

Ken

Ken Burdick · « **Reply #33 on:** October 29, 2015, 11:50:14 AM »

here is a picture of Dick Shannon's C speed ship. It has a coffin style tank but is a side winder so yours being an upright will change the orientation of the tank. It's hard to see the angle in the front of the tank, but it's there.

bob whitney · « **Reply #34 on:** October 29, 2015, 02:05:16 PM »

looks like u are going to have a pretty big hole in the side of the fuse for that needle valve

john ohnimus · « **Reply #35 on:** October 29, 2015, 05:08:14 PM »

Ran the engine tonight on the stand. Used a Rev-Up 8-8 Special Pro, Series 2 and saw 14,600, went to a Rev-Up 8-9N Speed Series 400 and saw 14,850 or so. The K&B needle worked great with good response. I could run it up to the wall and a little tighter and it would sag and lose. I also tried it without the venturi and briefly saw 15,200. So I think pressure will really bring the potential of the engine to light. Without the venturi I had no response from the needle. At one point I had it backed out and it was loose. Any ideas on what the max RPM I should be seeing might be ??
Ken,
I didn't install the tank in the pan. I bought it from eBay that way and was planning on replacing it. Or at least removing it and reinstalling it a little cleaner. Whoever the prior owner was kinda cooped it in with looks like liquid nails (?). It does seem like a well made tank and in good shape. Now... Which design to build......??

Thanks again for all of the input!!!!!!

C.T. Schaefer · « **Reply #36 on:** October 29, 2015, 05:20:56 PM »

You should be able to find a Fox or K&B pressure fitting. They are 4-40 and have the right sized hole in them. Drill and tap the center of the backplate. Boom.

When you get that done you can ditch the venturi and get some numbers more typical to what the motor will do. If you can find an APC 8x8 then others around the country/world will be able to relate to the #'s you are sharing. Bear in mind, I'm not suggesting the 8x8 is the best prop for your plane, that will only be learned from testing. It's really just a comparative tool. You are blazing new territory!!

C.T. Schaefer · « **Reply #37 on:** November 05, 2015, 06:46:52 AM »

John, Any word on the LA .40 testing? On another note. A Fox .35 speed plane might be fun. Speeds in the near 100ish area and a chance to fly it at Brodak next year!!

Ken Burdick · « **Reply #38 on:** November 05, 2015, 11:05:32 AM »

sounds about right re the needle without the venturi in. A pressure system will solve that. No worries on the pressure fitting
just be sure whatever you use has a very small hole. .010 is good. I use a piece of wire and make it sooty with a candle flame, stick it in the fitting and solder. Then twist and remove, you now have a nice small hole. This is important because a 1/16 hole or so, will pull fuel back into the engine while trying to start, the lil hole makes life much-o better-o.
There is a sure fire way to make an engine not run....put it in a cowling.

john ohnimus · « **Reply #39 on:** November 06, 2015, 05:26:48 AM »

Ken,

I like the idea for the restrictor in the pressure fitting. Still trying to figure out which plane to build aroung this setup...?

Ken Burdick · « **Reply #40 on:** November 06, 2015, 09:29:59 AM »

That's easy. Contact Marty and get his plans for the C speed model/ F-40. I'd spell it for you but would get it wrong. Here is a link to the article when he and I revamped C speed.

http://flyinglines.org/si.speed.html

"The Move" By Mike Hazel is a great flying airplane and simpler to build than some. It's held many records so it's tried and proven. Poke around speed times or google and I'm sure you'll find plans. Another wat to go would be to copy an old ama rat racer, I stopped flying them when they were inching close to 160 mph, so they are every bit as good as a speed ship.

Let us know what you decide.

Ken

Al Ferraro · « **Reply #41 on:** November 08, 2015, 08:24:51 AM »

This is what I use in the pressure line between the engine and the tank. You just insert it inside the line, they are great for tight areas.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXET36&P=7

Chad Hill · « **Reply #42 on:** November 10, 2015, 06:06:04 PM »

I recently picked up an OS 35 AX. Any suggestions for a venturi size? I'm really thinking about trying it for combat, but that motor doesn't seem to have made its way into those circles yet. Anybody have anything to say about it here? Thanks.

Ken Burdick · « **Reply #43 on:** November 10, 2015, 07:44:55 PM »

Too slow for Fast, too fast for slow. It should be fine for speed limit combat. You might also use an LA .25 for speed limit.
I suspect the engine is made for sport / stunt as the RPM rating is 16k.

Fly clean.

K

Motorman · « **Reply #44 on:** December 08, 2015, 10:50:04 PM »

Did the LA40 ever fly?

MM

Ken Burdick · « **Reply #45 on:** December 09, 2015, 10:47:06 AM »

Ditto, inquiring minds and all that.....we are just 6 months from record setting speed contests.

Tim Wescott · « **Reply #46 on:** December 09, 2015, 11:49:10 AM »

These may be interesting. They're written for the 25LA, but will probably mostly apply:

http://flyinglines.org/kb.la25rework.html
http://flyinglines.org/advanced%20rework.htm
http://flyinglines.org/kb.frankenstein.html
http://flyinglines.org/kb.darkside.html

Ken Burdick · « **Reply #47 on:** December 10, 2015, 10:00:58 AM »

the articles were written as the individual project progressed so you get benefit of frustrations along the way and how they were overcome.
Just got the piston and liner sets back from chroming (on the way) so I can now eliminate the crummy nickel plating they come with. This engine has been an unusual challenge.

K

john ohnimus · « **Reply #48 on:** December 14, 2015, 04:53:32 AM »

I have put the project on the back burner until I get the Noblarf finished or at least to the point where I am putting some color on it. I still have a couple of weeks to go yet. I did manage to construct a start box for the speed ships. Turned out nice. I hope the little Kavan starter has enough omph!!

Ken Burdick · « **Reply #49 on:** December 14, 2015, 09:30:51 AM »

it should turn it over well enough. I hand start my D ship. Have you seen how combat fliers start a Nelson .36? Small prime and a backwards slap (not flip through) It will bounce off compression and start. ......much less work than fiddling with a starter but less safe.

K

Tim Wescott · « **Reply #50 on:** December 14, 2015, 11:47:49 AM »

Quote from: john ohnimus on December 14, 2015, 04:53:32 AM

I hope the little Kavan starter has enough omph!!

This is a "well, duh" thing if you've used starters before, but it came as a surprise to me when I first saw it. And you're a CL guy, so maybe you've always averted your gaze when those newfangled starter thingies were taken out.

Turn the engine backwards against compression, then wield the starter -- by the time it gets on compression again it'll have a fair bit of momentum to carry it over, and the engine will spin (but maybe not start -- that depends on you). It takes a lot less effort for the starter when you do that.

john ohnimus · « **Reply #51 on:** December 14, 2015, 01:19:40 PM »

I've observed the technique on numerous occasions. Just a little leery hand starting those little sharp props!!!

Tim Wescott · « **Reply #52 on:** December 14, 2015, 06:07:33 PM »

Quote from: john ohnimus on December 14, 2015, 01:19:40 PM

I've observed the technique on numerous occasions. Just a little leery hand starting those little sharp props!!!

Wearing a nice thick glove will vastly increase your chances of having all the pieces to give to the surgeon.

john ohnimus · « **Reply #53 on:** December 14, 2015, 06:10:09 PM »

I already have "26" reasons from a previous encounter with an APC to careful.