MJD

My Feedback: (1)

Never knew people got so serious about hot rodding .020's, but hey, when there's big money at stake nobody likes to lose. What's next, $10 3x3.25 scimitar blade CF speed props?

I'm really glad those 1/2A props worked out.

hllywdb

Yeah, vibration is a killer. That's why Harleys have such a large top motor mount. Watch an FLH (rubber mount) HD next to a soft tail (hard mount) HD and the FLH motor looks like it's vibrating out of the bike while the softail looks smooth as glass. It's just transfering the vibration to the frame. It's why the softail goes through batterys faster, they break plates. Transfering these vibrations to be absorbed by our airframes probably isn't the best long term for the glue joints or electronics, but we usually break them before then anyway

I used to live about 20 miles up the road in Palm Bay. Dave Platt calls that home. We had a huge subdivision go bust right after they cleared the whole thing, the size of a small city, paved roads and all, just no houses. He bought a lot just so he could go out and fly FF there. At the same time Bob Violet lived across the street from me when he was first starting his jet business. The world gets small sometimes.

If I had an 020 freak move next door you'll see a new thread on a GLH with a polished carbon fiber flat bottom wing with a laminar AC back around 60%.

aspeed

Last winter I was looking at some real estate in Fanny Bay. I think it was around there. I heard about that other big subdivision. Weird place. You can take ATV's and stuff there because no one lives there, but there are still cops to give speeding tickets.

hllywdb

Yeah, Bombadier built a plant there. They dug out a lake for testing wave runners, so the big mountain of dirt left over is a big playground for dirt bikes and atvs. I used to run out there all the time. Got great mud bogs too. Since the roads were so long and straight, they used run drug smuggling planes in at night. They would line both sides of the road with those big citronella candles for runway lights. So the cops put in a bunch of speed bumps on all the main roads. Hate to be the first guy to find them durring a landing.

MJD those props cost me $3 a piece. To say that I'm pleased with them is an understatement.

aspeed

The Russian stuff is a good value. Their motors too. Chinese is cheap and sometimes a good value. I think the props are a bit too small for an .049, as well as the F2D props they make for a .15. I almost blew up a .15 using one of them. Great props for the money though, and perfect for a .10. Very well made, and 'sometimes' take a good crash.

hllywdb

Their props are made for motors with names like Fora, Profi, Cyclone, and Nelson. So the concept of "normal opperating rpm" is slightly different than for a sport motor.

aspeed

I put the F2D prop on an AP .15 and it went 24,900 rpm, but the rod got sloppy after one run. I have been using it for a little combat putterer on a 7-5 prop since. My ASP .15 blue head motor went went 25,700 with the same prop. I think the Fora is closer to 30,000. I haven't checked, it is too cold to adjust needle valves now. I made a new head for the ASP for the Turbo plug and it matches my Fora on a 7-5. Can't say if it will hold together near 30,000 with the little fiberglass prop though. The Fora is a lot lighter too. I guess I will have to order a few .049 fiberglass props too for the little Fora. I have to find a field to play with no muffler too.

hllywdb

There is no way I would stand anywhere near an AP or ASP 15 going over 20K!

I moved the CG forward quite a bit and reduced the throws, so I may give it a whirl again tomorrow if the weather is good. I've also got a Jr Falcon with a 061 and a 40" Kadet style stick built with a Medallion 09 with throttle sleeve that just need to run a bit so they don't gum up. When the hanger starts getting full I almost need a spreadsheet to keep track of the rotation schedule to keep things running good. Next trip up to the club I have a 1970 fabric covered H-Ray with a 1968 OS 30 that needs to be run too. Got to remember to bring some 25% castor fuel for it too.

MJD

My Feedback: (1)

The F2D engines typically run 30-33k, the props are in the 6x4, 6.3x4, range. Not much load for a sport .15!

The first run on my Profi .061 on a FG 1/2A combat prop was around 34k, on the rich side. Nothing for those little engines.

DeviousDave

I remember when I raced Sp400 pylon at the NATs, people (who usually had no plans to race) would light up the forums about how it was intended to be a beginner's class, not one with composite airframes, 2 flight motors, and hard to find batteries.

I always put those costs far behind the gas it took to make the 6 hour dive to Muncie. I appreciate a guy that looks at the rules for what they don't say and does what he has to in order to be competitive.

I sure wish 1/2A Pylon could make a comeback with modern airframes that were sized appropriately..

aspeed

1/2A pylon seemed pretty popular in the 1980's. I was just going through some old magazines and found a few plans. 1/4 midget .15 size looked pretty serious, and would likely work on windier days. Some guys east of Toronto had some club races with Sig Scamps, and later with a coroplast one design delta that was popular for a while too. It used a .15 to .25. I heard info that the .15's would get around quicker, and the LA .15 was pretty competitive. 1/2A would likely have to be limited to Norvels or everyone would need a Fora or something that costs too much for kids or noncommiting type people. There are a few on one of these forums that use a Surestart and a one design pylon plane (Pole Dancer)for club racing.

hllywdb

My old club in the 80's used the Sig Super Sport and we put 20's on them. The rule was you could have ball bearings or schnuerle porting, but not both. I think the kits were $8.99 back then and a spare foam wing was $4. It wasn't super fast but it was cheap enough that no one got mad after a mid-air. Had a lot of fun. 1/2a was fun club racing with GLH's or Sig Hummers. As long as everyone agreed on a motor, say a TD and we all ran the same. I realy miss the old ACE and Sig kits with foam wings. It made it cheap and simple to do a lot of club stuff with. In most of todays clubs you would have to go electric to get any participation but even a leekie GLH event would be fun. I seriously doubt I could get any takers for a 020 GLH pylon event. Not sure how you would mark them to tell them apart anyway at that size and speed. I have a hard time tracking my own in a 100 acre field. Put up 3 more and I'd have to build them 6 at a time just to finish the day.

hllywdb

OK, some more to report. Sorry, no video yet. This morning the wind died down to under 10mph (from the 20-25 we had this week). As noted earlier, I moved the cg forward to where someone not so deranged might put it. I also moved all the linkages to the innermost holes on the control arms. I set up the first flight with the stock cox prop to get things trimmed out. It was MUCH easier to fly, even enjoyable. The next flight was with the cut down prop and I went a tad rich just in case. A little more trimming then went for a hot flight. Now this plane is fun to fly.

Had some difficulties with air bubbles in the line. These are so suceptable to vibration and don't like it a bit. I may have to switch to through bolts instead of screws. On the same note, lightening the pistons makes the vibration much worse. They are not like the 049, it may be that the crank just doesn't have enough mass to deal with the slight bit of inbalance caused from lightening the pistons. Both pistons I tried lightening gave the same results, more vibration. So for now I am going to work on a more solid mounting and may try fine tuning the prop. I will try and get some video when I get a chance, will probably try and get some more flight time in tomorrow as it's a lot of fun to fly. In it's present configuration, I am looking forwrd to making an attempt to pass the 70mph mark, but will definately need some of Bob's modifications to get into the 26-27k range.

skaliwag

My Feedback: (1)

Can you Dremel a little off the Counter Weight? (I'm not a Motor Head so don't laugh).

hllywdb

Technically yes, but you would really want to drill small holes in it to remove wieght. The problem, at least for me, it creating an apperatus delicate enough to see when you were balanced. Not to mention the problem of the crank pin being on the end of the crank, so even if you supported it from the center of each end, you can't rotate it. And I am not willing to bet that Cox got the holes dead center either. Especially in the later years.

combatpigg

My Feedback: (3)

I've had good results taking material from the counter weight of larger engines. It's hit and miss sort of like tuning a pipe.
Bubbles in the line must be solved before the engine gets fried, that's for sure. In theory an engine with a lighter piston has the potential to run smoother than the heavier piston ever could and it takes who knows how much strain off the crank and rod.
Looking at this positively, you've removed enough material from the piston to make a difference and now the divot you take from the crank is child's play compared to working on the piston.

hllywdb

Got a chance to get a small video this morning. I was by myself so pardon the HD Hero fishbowl look. I added a thin layer to the firewall and bolted the motor all the way through. That solved the air bubble issues.

http://www.youtube.com/watch?v=ciwrgHfknXE

combatpigg

My Feedback: (3)

That's totally awesome..!!
It sounded so happy with the fuel system upgrades and prop.
I hope it lasts you for a long time because it is quite a novelty item.

straitnickel

WOW!, GLH is no joke.

hllywdb

Thanks CP. This is a good benchmark for what can be done with just a plain jane TD and the right prop. Next I am going to run a modified TD on it with a bladder. Right now it's a blast to fly for a little plane, but you know how it is when you KNOW you are leaving too much speed still left on the table. I am also going to replace the servos, the 6g chineese ones are glitchy. The double loop in the video was meant to be a single but the elevator servo stuck for a second. So I kind of eased off and kept it out in nice easy circuts until it landed. I am leaning toward the Futaba 3111's or 3114's. Anyone have any input? The 3114's have a good amount of torque too.

I figure there is still at least another 10mph to be had as the launch is still way too strong.

combatpigg

My Feedback: (3)

What do you figure the inflight rpm was..?
Whatever it was, the engine never hicupped or seemed to vary much in rpm after the intial unloading. It sounded right in the sweet spot.
Yes, it had a bulletlike launch, I'll bet it will do vertical launches.

hllywdb

I had shaved the prop just a bit more. Slightly thinner and more taper to the end, but still kept it at 4". I was getting just over 21k on the ground. While I had the engine off to setup the bolt throughs I sealed the case to tank with rtv and put in a new backplate gasket. I've been using the tiny fuel line from texas timers which stays on the tank better.

You can see it's a tough little bugger to keep track of once it's going, especially on a dark day, keeps me on my toes. The bigger GLH, even at 100 is much easier to stay on top of. But she flies nice and it was around 10mph wind today. Enough that I didn't want to fight the wee stick that I brought so I never put it up. Plus I was having too much fun with the glh Never thought I would enjoy 020's.

MJD

My Feedback: (1)

I lost track, what prop are you running on it there? That is a solid engine run and great performance. Nicely done.

combatpigg

My Feedback: (3)

MJD.......The Russian .049 combat prop you recommended [if I am keeping this thread straight]..?
I do not think it is possible to make the prop blades too thin before you see diminishing returns. Keep thinning them out till you can see light passing through them.

hllywdb

Yes its a cf combat prop from the Ukraine. Its a 2.75 pitch. CP these are already see through at .045 . I have taken the profile down much thinner. I'll have to post a picture.