RE: How to Quiet a 50cc Gasser? Help!
[quote]ORIGINAL: Flyfast1 I have also tried a Zoar 22x10, which reduced the prop speed, but it was still too loud. [/quote] You need to reduce prop speed with more pitch or more blades, not diameter. It is tip speed that makes the noise and a bigger diameter prop at lower rpm will still be noisy. Try a 20x12 or a 3 blade and see what that does for you. Mark
Posted on: 9/9/2010 4:15 PM by Author "mmattockx" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=9991038

RE: Classic Pattern and the economy
[quote]ORIGINAL: dhal22 i'm thinking my Blue Angel build will cost a $1000 or more. the canopy and wing cores were $120 plus shipping, the wood was at least that much, spring air retracts $150, nib OS 61 ABC SF-P $250. i still need to buy the header and pipe ($100?). wheels, axles, fuel tank, engine mount, DEPS, cables, fibergass cloth, finishing materials, paint $150 or more depending on paint choice. 6 quality servos, another receiver and battery, the list is growing here. but like 8178 said classic pattern is cheaper than 2m pattern. [/quote] Thanks, David. I hadn't thought of buying everything from scratch to buid the plane, since there is always a bin of servos, old gear and accessories available after flying for a few years. If you buy top shelf everything and do it all from nothing, it sure adds up in a hurry. Paint will only be $150 if it is the first model you use those colors on, after the initial expense it goes quite a way. Unless your idea of paint is way more expensive than mine, which is very possible. I agree, no matter how expensive classic planes seem, 2M is way more so. A YS170 is somewhere around $700+ from what I gather... The rest sort of follows that. Mark
Posted on: 2/9/2009 12:44 AM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8455529

RE: Classic Pattern and the economy
[quote]ORIGINAL: grcourtney Not really my p-8 wuz about $1500 by the time I wuz done [/quote] Gary, What did you put in it to get up there? I'm not being a smart a$$, I really would like to know. Mark
Posted on: 2/5/2009 10:47 PM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8443746

RE: Cutting parts through plywood?
[quote]ORIGINAL: Chad Veich My first choice would be a scroll saw but, if not, then a band saw with about a 1/8" blade. [/quote] +1. A scroll saw is a great choice, with a small band saw second in my books. Use a fine tooth blade to minimize splintering and rough edges. If you really want to go first class, cut them slightly oversize and true the edges up with a belt or disc sander. Mark
Posted on: 1/28/2009 8:41 PM by Author "mmattockx" in the forum "Scratch Building, Aircraft Design, 3D/CAD"
http://www.rcuniverse.com/forum/fb.asp?m=8413549

RE: I need some canister education
Try lengthening the header a bit, maybe an inch and see if that helps. As the canister heats up, it will resonate at a higher frequency. I bet this shift is enough to make your engine act like the pipe is too short and lose rpm with the heavier prop loads. Be sure the higher rpm claims were not done with a full tuned pipe setup. They will make significantly more power than your canister will. Mark
Posted on: 1/23/2009 1:13 AM by Author "mmattockx" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=8390666

RE: Manufacturers cost?
[quote]ORIGINAL: Tired Old Man Then come back and talk about mark up and excessive profit. [/quote] I for one hope that DA are making a decent profit. Even "excessive" profit. They are in business to make money, it is not a charity. The people who are complaining of gouging have never ran a business as their bread and butter and do not get the long hours, stress and effort that go into it. Making a solid living should be a reasonable outcome of that effort. If they are willing to take the plunge and carry the risk, then more power to them. If you don't like it, don't support them. But don't complain about "excessive" profit until you have been on the other side of the table and know what you speak of. Mark
Posted on: 1/22/2009 12:44 AM by Author "mmattockx" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=8386630

RE: What Carb??
Good advice. I will check the schematics to be sure the models I am looking at have two needles. Edit - I am looking at a WT-416 model that has two needles and a 13.5mm venturi. It also looks to have the primer bulb on it, is that an issue for aircraft use? I can't see why, but you never know... Thanks, Mark
Posted on: 1/19/2009 1:47 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8376166

RE: What Carb??
Awesome! Thanks for the help, av8tor. Mark
Posted on: 1/19/2009 12:30 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8375891

RE: What Carb??
Great info, Ralph. I have a question on these numbers, though. Shopping through fleabay gives me similar numbers, but not quite the same. Is there another list or a more comprehensive one? I see numbers like WT-257, 364, 416b, 644. None of which are listed on the reference. Any ideas on where to find more info on these? Thanks, Mark
Posted on: 1/19/2009 12:19 AM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8374543

RE: Wanted - 46cc Poulan or 50cc Echo
[quote]ORIGINAL: av8tor1977 Be sure to tape over any engine openings so that no metal filings/dust get into the engine. AV8TOR [/quote] Good point. I would have anyway, but I have also worked on auto and bike engines with heads / carbs / valve covers off. It only takes once dropping a small piece into a deep hole to never forget the experience and make sure you always cover every opeing before working on it. Mark
Posted on: 1/18/2009 12:10 AM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8370762

RE: Wanted - 46cc Poulan or 50cc Echo
Thanks, Av8tor. I will probably cut it off outside for the time being and keep the internal cut as a backup plan. I am going to use a small cutoff wheel and go slow, there is no way I will get it hot enough to hurt the seal unless I am completely incompetent. There, that should guarantee Murphy tries to come calling.[:D] Mark
Posted on: 1/17/2009 2:29 AM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8367648

RE: Wanted - 46cc Poulan or 50cc Echo
Got the Poulan 46cc short block in hand now. It sure is light without the extra bits, just over 35oz bare on my scale. I will now be ordering the conversion parts and an R/C Excel ignition from Brillelli Customs. Then I need a Walbro 201 carb and I am set... If anybody has one sitting around and wants to sell it, PM me with details. On the conversion, do you just cut off the crank extension that projects backwards? Looks like 5 minutes with a Dremel will have that cleaned up. Anything else that needs cutting off or modifying before I put the Brillelli parts on? Thanks, Mark
Posted on: 1/17/2009 12:59 AM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8367534

Early 90's MAN with Muffler Article?
As the title says, I am looking for an early 90's Model Airplane News that had an article on constructing homebuilt mufflers. I think it was in 92 or 93 and I believe the issue had a German aircraft on the cover, maybe an Me-109. The author was european and the article had details on the theory of acoustics and practical advice and details for homebuilt mufflers and mini-pipes similar to mousse can pipes. Any help or info would be great. A scan would fantastic. Thanks, Mark
Posted on: 1/11/2009 11:46 AM by Author "mmattockx" in the forum "Kit Building"
http://www.rcuniverse.com/forum/fb.asp?m=8345284

RE: Sheeting/gluing foam wings
The foam wing Bible: http://www.mackrc.net/patternwings2/index.htm Mark
Posted on: 1/10/2009 1:40 PM by Author "mmattockx" in the forum "Kit Building"
http://www.rcuniverse.com/forum/fb.asp?m=8342231

RE: Sig King Kobra Question?
[quote]ORIGINAL: Free Bird Tony, That engine comes with a tuned muffler and a 2-blade (12 or 13 inch) would be way to go. That engine likes to rev up. FB [/quote] Are you sure about that? All the other AX models are lower rpm torque engines. Mark
Posted on: 1/9/2009 3:58 PM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8338968

RE: Sig King Kobra Question?
A 3 blade prop is somewhat less efficient than a 2 blade, but efficiency is never very high on our list with the power loadings we run. You can overcome any efficiency losses by simply adding another click or two of throttle. The 3 blade 13x8 will make almost exactly the same static thrust as a 2 blade 14x6, but the thrust will not drop off as fast with increasing airspeed. Mark
Posted on: 1/9/2009 11:44 AM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8338202

RE: Plans for Rare bear or others
Well, Strega is a 'Stang. You could simply get some P51 plans in the scale of your choice and then clip the wings and alter the turtledeck to match pictures. Google Strega and you will find lots of pics for detail info. Mark
Posted on: 1/9/2009 10:47 AM by Author "mmattockx" in the forum "Scratch Building, Aircraft Design, 3D/CAD"
http://www.rcuniverse.com/forum/fb.asp?m=8338008

RE: Sig King Kobra Question?
[quote]ORIGINAL: bigedmustafa Don't forget to consider 3-blade props if you run a little short on ground clearance. Master Airscrew offers 12x8 and 13x8 3-blade props that should be a good match with the .75 AX [/quote] Good point. A 3 blade 12x8 will be about 80% of the load of an APC 14x6 and a 13x8 3 blade will be about 109% of the load. There are lots of ways to skin this cat without the 14" prop to contend with. Mark
Posted on: 1/9/2009 10:44 AM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8338001

RE: Sig King Kobra Question?
[quote]ORIGINAL: Tony Gag Jr. I thought a 12" or 13" prop was too small for the 75AX. I don't own one but I am just going off the stuff I have read about the 75AX. [/quote] Well, I used to fly a CG Ultimate bipe with a ST90 and APC 13x8 prop. I doubt a 75AX is going to turn more prop than that ST90 did. Prop load is also dependent on pitch, don't assume all props are only 6" pitch like the 3D guys want. Old style pattern planes like speed, which takes a smaller prop with more pitch. Just for reference, using a 14x6 as a baseline (I don't think you would run a 14x8 on any 75), a 13x8 is 96% of the load, and a 12x10 is 86% of the load. Not a huge reduction in load and much easier to get gear to fit with. I bet you would like a 12x9 or 10 on that combo. It won't hurt that 75 to let it rev a bit with a lighter prop load and there is always the left stick to work with, too.[;)][:D] Mark
Posted on: 1/9/2009 1:08 AM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8337115

RE: Wanted - 46cc Poulan or 50cc Echo
Gentlemen, I have bought a 46cc Poulan short block to be used for my project, just waiting for shipping now. I will update with any progress and results as I go. Thanks for the help and guidance. Mark
Posted on: 1/8/2009 10:30 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8336589

RE: Sig King Kobra Question?
[quote]ORIGINAL: Tony Gag Jr. Thanks. My biggest concern is the ground clearance since the 75AX swings a 14" prop. Tony [/quote] I think you will find the KK much more enjoyable with a higher pitched 13" or even 12" prop. It is not a 3D model and likes to fly fairly fast, not hang on the prop. Try an APC 12x8, 9, 10 and the 13x8 to see how you like those first. Mark
Posted on: 1/8/2009 10:26 PM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8336567

RE: Calling all Aerodynamicists !
[quote]ORIGINAL: grotto2 I would think the angle of dihedral would remain the same, thus the ratio of span to tip displacement would remain constant. [/quote] This would be my choice. Dihedral is an angle, not a linear dimension. They specify it as a distance under the wingtip, just because it is the easiest way to measure it. To be truly accurate, use the angle of the centerline of the airfoil and then calculate the distance under the tip for your reduced version. Mark
Posted on: 1/7/2009 12:13 PM by Author "mmattockx" in the forum "Classic RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8329738

RE: RCGF Engines
[quote]ORIGINAL: cmoulder I have done a bit of electric, and field recharging is a huge issue at the two fields where I fly. No commercial power supply available, and I have learned the hard way that if you charge a couple of 4500 mah batteries off your car batteries - and do it a couple of times - you'd better make sure you've got a buddy available for a jump start! Imagine the batteries for a 30-40% plane!![X(] [/quote] The electric pattern guys carry generators for this reason. Cheap flying, huh? Mark
Posted on: 1/7/2009 12:40 AM by Author "mmattockx" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=8328304

RE: Wanted - 46cc Poulan or 50cc Echo
Gentlemen, I have a lead on a Poulan 46cc short block. Price is very good (IMO), the engine is bare with no ignition or carb. Looking at Brillelli's site, they offer a prop adapter for $30, a carb mount for $30 and a hall sensor mount for $6. In addition, I would need an R/C Excel ignition box and carb. This seems more like what I was looking for and a reasonable deal to me. First, am I missing anything? Second, to find a seller for the ignition should I just search on R/C Excel in this forum or what? Last, where do I find a carb and what size is considered optimal on the 46? Thanks, Mark
Posted on: 1/4/2009 10:36 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8319716

RE: Wanted - 46cc Poulan or 50cc Echo
[quote]ORIGINAL: scott h i know in canada poulan pro 46cc,s could be bought at princess auto stores for 99 dollars. my freinds here tell me the echos are great engines . scott [/quote] That was mentioned to me in another thread. I haven't been in that end of Calgary for over a month, so I have not had a chance to take a look yet. Thanks for the reminder. Mark
Posted on: 1/4/2009 7:49 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8318964

RE: Wanted - 46cc Poulan or 50cc Echo
[quote]ORIGINAL: captinjohn I would really consider this deal! $98.1018" Gas Chainsaw ( At Menards) Capt,n [/quote] Thanks for the leads, guys. The only problem is I am in Canada and either I can't get stuff shipped or the shipping costs are prohibitive. That is much of why I am looking locally. Something like this looks good, but with shipping and exchange it is a $200 saw by the time I get it... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=110333646679&fromMakeTrack=true&ssPageName=VIP:Watchlink:middle:us Mark
Posted on: 1/4/2009 6:04 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8318481

RE: Wanted - 46cc Poulan or 50cc Echo
Thanks for the reply. I have been looking for those, I have called numerous small engine places locally here and none of them keep a junk pile or have used stuff like what I am looking for. It is like looking for a needle in a haystack at the moment, very frustrating. I have seen where I can buy new Echo shortblocks, but they cost as much as a new chainsaw and my goal is to not pay $350 for an engine. If I wanted to do that at this point, I could just go buy a new engine and not have to worry about converting it. At the moment there isn't even much in the way of used Brillelli or BME engines to chose from that I can find. Good thing it's a long winter and I can't fly for a while yet. Mark
Posted on: 1/3/2009 5:25 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8314118

Wanted - 46cc Poulan or 50cc Echo
I am looking for an unconverted 46cc Poulan or 50cc Echo to do my own conversion on. I have looked on the RCU classifieds, watched local used ads, checked Ebay and called local small engine repair places with no luck. I am not looking for a new engine, but one to convert myself for a relatively economical gas engine that has beam type mounts. Any leads, help very appreciated. PM me if you have one sitting that you want to move out of your shop. Thanks, Mark
Posted on: 1/3/2009 2:33 PM by Author "mmattockx" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=8313558

RE: 80" profile plans?
I believe OMP will sell plans only for their kits. I know I got a 79" Yak 54 short kit from Mike after they discontinued it. Mark
Posted on: 1/3/2009 2:26 PM by Author "mmattockx" in the forum "Scratch Building, Aircraft Design, 3D/CAD"
http://www.rcuniverse.com/forum/fb.asp?m=8313538

RE: What should I do?
Only one thing to do - get rid of her! 18 years or not, she has crossed a line that should never be crossed. You might want to wait until the company has gone before you let he know that it's all over.[:D] Mark (Another single guy who can laugh with impunity..[X(])
Posted on: 12/31/2008 7:48 PM by Author "mmattockx" in the forum "RC Pattern Flying"
http://www.rcuniverse.com/forum/fb.asp?m=8303689