Author Topic: One flip starts (Read 4287 times)

Tim Wescott · « **on:** December 30, 2013, 01:02:49 PM »

About two years ago, Richard Entwistle of the Fireballs taught me how to get consistent one-flip starts with OS engines. This has worked very well for me except for one contest, where I changed from 8% nitro to 15% nitro a couple of weeks before the contest and didn't realize that I needed to prime the engine over twice as much as I had been before.

Prime the engine by choking the venturi fully with your thumb
pull (don't flip) the engine through a set number of turns (the exact number is different for every engine, and changes a lot with fuel, and a bit with temperature. So far it's been between three and seven.)
Flip the engine a dozen times, to distribute the fuel throughout the engine
Put on your glow starter, signal the judges, give it one flip, and try not to stumble over your feet when you walk out to your handle

The key seems to be figuring out the exact amount to prime, and doing the dozen flips to get the whole engine uniformly primed rather than just having a pool of stuff in the crankcase.

My flying buddy, once I talked him into trying this, has had success with this basic method on an ST-51, except that he flips it while choked instead of pulling, because it's a ringed engine and seems to need a bit of speed to develop suction.

So -- do you achieve one-flip starts? What engine, fuel, and procedure do you use?

PaulGibeault · « **Reply #1 on:** December 30, 2013, 02:58:22 PM »

Hey Tim,

To achieve 1 flip hand starts on a 2 stroke you need 3 things:

1. Good glow from the battery to the plug.
Some glow drivers give a dull glow & this will start the engine eventually, but rarely on the first flip. I trouble shot one case when a fellow had a slick electronic driver that showed "all green" lights when attached. When the plug was removed from the engine & driver attached, the element glow was VERY DULL, even though the driver indicated all was good. Of course it wasn't! The engine popped & farted, but was a real pain to start. We switched to my own known 'Glo-Bee' starting battery & the first flip starts returned. The guy thought it was magic... Run down 'Ni-Starters' are bad for this, which is why many users keep a fresh charged one handy in their pocket if there's any doubt at all.

2. Good engine compression seal.
Even the odd new engine, or poorly broken in engine will not have a "good enough" piston seal to start first flip. They will start eventually & run OK, but not be first flipper. This is the hardest thing to describe & trouble shoot. Often only a really experienced modeller can determine this precisely... wish I could offer more on this item, but can't on the Internet... The good news is that more engines are made today with good sealing pistons than many years ago when it was more hit & miss.

3. A healthy prop flip!
A mushy or soft flip gives a marginal or dicey chance of a first flip. So if you need to wear a glove or finger guard to give the engine a good whack, well then that's what you need...

The above is the basis of what any first flip engine needs. There are secondary items such as you alluded to. They are:
- the fuel must not dirty or contaminated with water
- the tank must be mounted reasonably. Not too high or too low or too far aft which can cause too rich or too lean starting.
- tank, fuel lines & filter MUST HAVE NO LEAKS Any leaks & all starting bets are off.

All the above being said, you are correct in observing that the pilot needs to observe what a given engine is asking for. i.e. how much prime, how much choke, etc. People like Randy Smith have actually written out exact sequences for first flip starting of his PA engines. Brilliant! Still one of our guys was having trouble starting his PA stunter, claiming to have followed instructions. Fortunately, Randy himself graced our contest one day & walked this fellow through the sequence. First flip starts now.... So sometimes you can read all you like, but it's the actual DOING that teaches you.. We were quite impressed!

You've asked a great question Tim. I wish you the best of luck in your endevours.

Cheers, Paul

Steve Helmick · « **Reply #2 on:** December 30, 2013, 04:38:03 PM »

I showed Tim how to get a one-flip start with the Magnum XLS .36/Twister I gave him. Also showed him how to set the NV with a tachometer, which apparently went in one ear and out the other....

Steve

Tim Wescott · « **Reply #3 on:** December 30, 2013, 05:29:43 PM »

Steve: One flick with an electric starter doesn't count. Seeing it start without the glow igniter attached was interesting, though. And I use a tach all the time, now.

Paul: Hey, a team race guy would know a lot about one-flick starts, wouldn't he?

RknRusty · « **Reply #4 on:** December 30, 2013, 07:00:44 PM »

Good thread.
I'm fairly new to .25 and larger engines with hard tanks(as opposed to bladders), and my stunt mentor Wayne showed me this procedure, and what y'all have said is spot on. I expect it would have taken me some frustrating fooling around to figure this out. He kept insisting I ditch my silly homemade battery box with a clothespin electrode clip and buy a clip-on nicad igniter. But I resisted.

Then, Gene Martine was helping me practice one October day in Huntersville. He pooh poohed my battery pack after watching me flip 20 times, and handed me his nicad clip-on... vrooom! So I finally upgraded and never looked back. I've never seen a plug glow as brightly with my old dual D alkaline pack. My TT .25 takes 12 choke pulls and it roars to life on the first or second flip. My fp 35 on another plane only takes two choke pulls to light the fire. That may have something to do with my tanks.

Yet another word of wisdom from my mentor came when an RC guy was watching us one day and asked why not just use a starter motor. Wayne told him if it won't crank by flipping, then it has some other problem that needs to be addressed, or you'll never get the consistent engine runs you need for stunt flying.

Rusty

Tim Wescott · « **Reply #5 on:** December 30, 2013, 08:10:41 PM »

Using a starter is not manly
Using a starter mars the spinner, by leaving an ugly black ring. Even in an event without appearance points this will affect your flight score because you'll be staring at your spinner thinking "damn, I should never have let Steve get close to my plane with that starter" instead of paying attention to the wind direction. Polishing it out when you get home from the contest is a PITA, too.
and finally -- using a starter is not manly

Brett Buck · « **Reply #6 on:** December 30, 2013, 08:19:39 PM »

Quote from: Tim Wescott on December 30, 2013, 01:02:49 PM

About two years ago, Richard Entwistle of the Fireballs taught me how to get consistent one-flip starts with OS engines. This has worked very well for me except for one contest, where I changed from 8% nitro to 15% nitro a couple of weeks before the contest and didn't realize that I needed to prime the engine over twice as much as I had been before.

Prime the engine by choking the venturi fully with your thumb
pull (don't flip) the engine through a set number of turns (the exact number is different for every engine, and changes a lot with fuel, and a bit with temperature. So far it's been between three and seven.)
Flip the engine a dozen times, to distribute the fuel throughout the engine
Put on your glow starter, signal the judges, give it one flip, and try not to stumble over your feet when you walk out to your handle

The key seems to be figuring out the exact amount to prime, and doing the dozen flips to get the whole engine uniformly primed rather than just having a pool of stuff in the crankcase.

My flying buddy, once I talked him into trying this, has had success with this basic method on an ST-51, except that he flips it while choked instead of pulling, because it's a ringed engine and seems to need a bit of speed to develop suction.

So -- do you achieve one-flip starts? What engine, fuel, and procedure do you use?

Pretty much the same thing. Getting it choked and aerated properly is the key and it is very different from engine to engine.

The only thing I do differently is that I rarely flip the engine, always back-bump. That way, when it starts, your hand is not near the blade. Note that this is not actually flipping through backwards, it's just slinging it backwards up against compression. I am not willing to flip the bigs ones forward except under extreme circumstances. Little ones, or something like a Fox, maybe.

Other things that are pretty consistent - it takes more choking when it is cold than hot. For the PA, it needs a few pulls-through cold and usually nothing or one when hot. The RO-Jett takes much more, maybe 6+ cold or 3 hot. You can usually hear when it's right, it will sound vaguely sloshy when right.

Brett

Tim Wescott · « **Reply #7 on:** December 30, 2013, 10:35:59 PM »

Brett, if there's a NW Regionals in 2014 I'll have to come watch you start your engine.

I'll also bring some traffic cones or police tape to put up, to remind myself not to go traipsing through the Expert pits, across all the experts' lines. (blush).

Steve Helmick · « **Reply #8 on:** December 30, 2013, 10:48:20 PM »

Most of (the few of) us left in the NW that fly manly engines encourage the use of electric fingers, because we are not that keen on the sight of blood. Especially those who saw Mike stick his finger into a pencil sharpener at Eugene a few years ago. I liked starting the Magnum .36 with one flick of the pink finger. I haven't got the mojo working on the PA .51 or .46VF, tho, and it has me more than a little bit PO'd. If I can get it figured out, I'll gladly go to the back-flip or spinner-twist. CF props are kinda scary. I should give some to Tim.

Steve

Geoff Goodworth · « **Reply #9 on:** December 31, 2013, 12:10:18 AM »

I think that tanks play a role; also the age of the engine.

My TT25 with the LA 25 piston and liner was first set up on the test stand and run for two 2 oz sessions—about 10 minutes total. It has now done about 25 6–7 minute flights. The tank is a Brodak profile uniflow—the one with the pickup and uniflow tubes out the top and the model is a Ringmaster. Starting routine is two flips with the venturi closed, about six flips to get the fuel into the engine, connect the battery, flick once, remove battery and fly.

A similar routine with the LA 46 on a profile Shoestring with a Brodak deep profile uniflow tank. Again, the engine only had about 4 oz of fuel through it on the bench and it has now done about 15 7-minute flights.

The Brodak 40 in an ARF Oriental is a bit different. The engine received the specified 20 approx 2 minute runs before installing it in the aeroplane and it has done about 20 flights of about 7 minutes. The tank is the Brodak all tubes forward uniflow specified in the build instructions. At the beginning, the engine must be upright. Then we choke the venturi and flip twice. We then flip 20 times, put the model on the ground right way up, connect the battery, flip once, remove the battery and go fly. I have to be careful because the Brodak 40 seems to flood easily.

Obviously, all the pistons and liners are fairly new and have not received much running in the total scheme of things. Also, all three engines sound different when they are ready to go. They sound/seem tight at the beginning and start to sound a bit wet and tend to flop more as they bounce off compression when they are ready to go.

Dave_Trible · « **Reply #10 on:** December 31, 2013, 07:20:14 AM »

Quote from: Tim Wescott on December 30, 2013, 08:10:41 PM

Using a starter is not manly
Using a starter mars the spinner, by leaving an ugly black ring. Even in an event without appearance points this will affect your flight score because you'll be staring at your spinner thinking "damn, I should never have let Steve get close to my plane with that starter" instead of paying attention to the wind direction. Polishing it out when you get home from the contest is a PITA, too.
and finally -- using a starter is not manly

And using a starter can bend the rod if the engine gets loaded up.

Dave

Duke.Johnson · « **Reply #11 on:** December 31, 2013, 09:13:45 AM »

Quote from: Tim Wescott on December 30, 2013, 10:35:59 PM

Brett, if there's a NW Regionals in 2014 I'll have to come watch you start your engine.

I'll also bring some traffic cones or police tape to put up, to remind myself not to go traipsing through the Expert pits, across all the experts' lines. (blush).

Check out Flying Lines. 2014 Regionals are look good for Salem.

steven yampolsky · « **Reply #12 on:** December 31, 2013, 09:51:59 AM »

A few thoughts:

1) Please learn the back-bump flip starts! They are safer!
2) If you flip the prop forward only, the fuel will be pushed into the cylinder and may have difficulty mixing with air. That is, the mixture will be too rich and may cause flooding. It is better to do a few flips backwards to move the fuel into the crankcase.
3) Most motors do not need a lot of fuel to start. A 2-4 flips while choking is enough for most engines. If your motor is not getting fuel after a few chokes, there is something wrong with your fuel system. Fix that instead.

Mike Scholtes · « **Reply #13 on:** December 31, 2013, 10:05:10 AM »

I almost always get one-flip starts on my Continental A-65:

1. Check for secure tiedown at tail, remove wing tiedowns, set wheel chocks
2. Throttle full open, magnetos double-checked to "off"
3. Pull prop through three for four times over compression till squishy sound in cylinders is heard
4. Double check throttle set to slightly above idle, mags on "both"
5. Grasp prop blade, kick right leg high, swing prop while kick leg back and pivoting and turning away from prop

Nearly always works. If not, wait 10 minutes and try again

Brett Buck · « **Reply #14 on:** December 31, 2013, 10:23:15 AM »

Quote from: Steven Yampolsky on December 31, 2013, 09:51:59 AM

A few thoughts:

1) Please learn the back-bump flip starts! They are safer!
2) If you flip the prop forward only, the fuel will be pushed into the cylinder and may have difficulty mixing with air. That is, the mixture will be too rich and may cause flooding. It is better to do a few flips backwards to move the fuel into the crankcase.
3) Most motors do not need a lot of fuel to start. A 2-4 flips while choking is enough for most engines. If your motor is not getting fuel after a few chokes, there is something wrong with your fuel system. Fix that instead.

If you flip forward, it definitely needs less choking. The back-bump blows some of it out the intake, so you need more for that. The advantage is that it will blow out more if you overdo it.

How much choking is required depends on the engine. Some engines take much more than 4 chokes cold.

BTW, you know you have done it right if it goes right to full blast on start. If it takes a while to spool up, you missed it by a bit. Fortunately back-bumping is pretty forgiving.

Brett

Tim Wescott · « **Reply #15 on:** December 31, 2013, 10:35:13 AM »

Quote from: Mike Scholtes on December 31, 2013, 10:05:10 AM

5. Grasp prop blade, kick right leg high, swing prop while kick leg back and pivoting and turning away from prop

So, in spite of Brett's advise to back-bump the big ones, you pull it through forward?

Oh, I hate these inconsistent answers

!

Mike Scholtes · « **Reply #16 on:** December 31, 2013, 02:29:49 PM »

Right, plus no electric starter on the spinner. I forgot to add "don't wrap your fingers around the prop trailing edge when giving it the "starting" pull-through. Place palms firmly on face of prop, not around it." Prop cuts from a metal Sensenich are SO annoying.

Tim Wescott · « **Reply #17 on:** December 31, 2013, 02:34:21 PM »

Quote from: Mike Scholtes on December 31, 2013, 02:29:49 PM

Right, plus no electric starter on the spinner. I forgot to add "don't wrap your fingers around the prop trailing edge when giving it the "starting" pull-through. Place palms firmly on face of prop, not around it." Prop cuts from a metal Sensenich are SO annoying.

I was wondering how you avoided serious injury in the case of backfire. I guess that's it.

Matt Colan · « **Reply #18 on:** December 31, 2013, 05:37:23 PM »

I use a piece of pipe coupler to start all my engines except the big RO-Jett's I have. I still use a chicken stick. for one flip starts I generally choke it 3-4 times, flip it once or twice choked, then flip it a couple more times until I hear that wet sound I like to hear. Put the battery on and most of the time I get 1 flip starts flipping it backwards.

Brian Hampton · « **Reply #19 on:** December 31, 2013, 07:41:59 PM »

The point about plug heat is worth mentioning again. I use a power panel but because plugs can vary considerably as far as power needed I always check a new plug first before fitting it to the engine. Turn the power right down, hook up the plug then slowly wind up the power until it glows a reasonably bright orange then check where the needle is on the panel. Other than that the rest is just getting to know exactly what a particular engine likes to have as a prime for a one flick start. Priming means getting a small amount of fuel up into the crankcase and then getting just the right amount into the cylinder as well. For me this varies from my Enya 61RE which requires considerable priming before it begins to feel slightly loose and "wet" sounding to my Irvine 40RLS which needs very little and very precise priming because a fraction too wet and it'll try to take my finger off. With zero nitro I usually get a one or two flick start just about every time.

The only engine I could never figure out was one of my 40VF's which flat refused to hand start (or generally not even fire) on the first start of the day and needed the electric finger. After that, an easy one flick start for the rest of the day.

Derek Barry · « **Reply #20 on:** January 03, 2014, 11:58:11 AM »

I run mostly PA engines (exclusively for competition) and I have a pretty good success rate with one flip starts. Like Brett, I do not flip it but rather sling it back onto compression.

1) I cover the venturi and flip (not pull) the prop through 3-4 times. (again Brett is right, less in the summer more in the winter)

2) On my final flip I uncover the venturi half way through to pull air and fuel into the cylinder.

3) 2-3 full flips through and 1-2 back flips to aerate.

4) put battery on.

5) Spinner flip backwards

6) Go Fly.

This works for almost every engine I have tried. When I started playing around with RC I use to make bets with the other guys that I could start their engine with one flip, I never lost. My Saito 125 will start exactly the same. One spinner flip backwards. That really blows the RC guys away.

Derek

Jim Kraft · « **Reply #21 on:** January 03, 2014, 08:22:35 PM »

Back when I was flying R/C pattern it was pretty common to snap the spinner backwords to start. I was flying a YS 60 short stroke from about 86 to 94, and after a choke or two it would almost always start that way. Also, most were running some form of APC type props, and nobody wanted to slice their finger on those.

Gerald Arana · « **Reply #22 on:** January 26, 2014, 05:52:07 PM »

All this about priming and flipping is good stuff, except: Be extremely careful when flipping (priming) a high compression engine on a "HOT" day. It can start without the glow starter being on the plug!

How do I know this? Because it happened to my a few summers ago in Woodland with my Strega/ Enya 7033 powered ship.

There I was ready for an official flight, two or three chokes on venture and several (I don't remember how many 4 or 5 maybe) flips and WAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA she was running. Damn good thing I didn't have my finger in the arc of the prop. Luckily only my pride was hurt.

Jerry

Daniel_Munro · « **Reply #23 on:** February 03, 2014, 01:05:45 PM »

Having only recently started flying control line again after a 10 year break I've realised most of my engines are just about worn out. I've only one that starts and runs nice. An old OS .20fp on a peacemaker. I choke the engine and turn over 5 turns then flick the prop over 6 turns. Turn on glow and 9 out of 10 times one decent whack and she starts first time. Current tank setup being a simple wedge tank with a feed and a vent/filler on muffler pressure gives a nice 4/2 break. The peacemaker I built when I was 16 flies well and can do the pattern but is not the best setup for clean tidy aerobatics. Need a bigger plane, but at least it's got me flying again.

Author Topic: One flip starts (Read 4287 times)

steven yampolsky