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Cox Engine of The Month
Racing Mongoose
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Re: Racing Mongoose
fredvon4 wrote:The tank he is using is plumbed for Uniflo so yes there is a ram air effect from the Tee Dee venturi fast fill receptacle.
I love Colmans Mustard for domestic things like hot dogs or Reuben sandwiches. For my German sausages I prefer Händlmaier's Würstlsenf Mittelsharfer Senf!
I had my first Reuben sandwich at Bebe's deli in Chicago last week. It was excellent!
ian1954- Diamond Member
- Posts : 2688
Join date : 2011-11-16
Age : 69
Location : England
Re: Racing Mongoose
ian1954 wrote:I like the wings on this - I always find that being able to see through the covering to the ribs and construction adds something. The finish looks superb.
I would buy it to use the bottle but Colmans mustard tins make excellent tanks!
I like the use of the venturi for fast fill but does it double as an air scoop?
Thank you Ian. The finish is silk span applied with full strength dope then filled with dope/cornstarch/acetone sanding sealer then dc540 primer. The red is rustoleum painters touch. It went on thick and ran so I imediately wiped it off, waited two days and wet sanded the whole mess back down. Total PITA!
The mustard was dumped as it was only purchased for the bottle, I like a good Dijon. I do use Colman's in my crab cake recipe. I'll have to mix some up and try as a condiment.
How many tanks do you think I can get from the 16 ouncer!
The spicy Jim.
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
I'm going to take some of these home for tanks, they seem slightly thicker than the Colman's tins.
Last edited by JPvelo on Sun Nov 09, 2014 9:35 am; edited 1 time in total (Reason for editing : Spelling)
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
ian1954- Diamond Member
- Posts : 2688
Join date : 2011-11-16
Age : 69
Location : England
Re: Racing Mongoose
As requested here's video. It's doing 74mph on 60ft lines. I have no doubt it could break 80mph with a different prop but club rules require a top flite 9x6.
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Thanks for the video but as a combat guy who loves the Mathis Mongoose I kept waiting for the tail chase this plane can do...LOL.
Do the rules allow you to shape or modify the props or do you have to run them as delivered?
Sounds to me like the engine could be spun a little tighter
Also for a tad less drag make sure on your next build to sharpen the LE and the TE. The wing shape, as designed is intended to turn tight...for pure level flight you don't have to worry about a stall or mush in turns up or down so a less blunt LE should gain some speed. The TE being very sharp reduces parasitic drag
Do the rules allow you to shape or modify the props or do you have to run them as delivered?
Sounds to me like the engine could be spun a little tighter
Also for a tad less drag make sure on your next build to sharpen the LE and the TE. The wing shape, as designed is intended to turn tight...for pure level flight you don't have to worry about a stall or mush in turns up or down so a less blunt LE should gain some speed. The TE being very sharp reduces parasitic drag
fredvon4- Top Poster
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Posts : 4002
Join date : 2011-08-26
Age : 68
Location : Lampasas Texas
Re: Racing Mongoose
Fred,
Unfortunately no prop mods. I'm going to try and get the prop rule changed to something like "commercially available props costing less than $5.
Yes it's a bit rich, my thinking is that restarts will be faster with a cooler engine. Judging from our first race the guy with the fastest pits will win this thing. That being said I've seen a tank with the uniflow plumbing set so that the engine richens up the last 1/4 tank to help with the restart. I may try my hand at building one. I've never soldered anything in my life but it's time to try.
Jim
Unfortunately no prop mods. I'm going to try and get the prop rule changed to something like "commercially available props costing less than $5.
Yes it's a bit rich, my thinking is that restarts will be faster with a cooler engine. Judging from our first race the guy with the fastest pits will win this thing. That being said I've seen a tank with the uniflow plumbing set so that the engine richens up the last 1/4 tank to help with the restart. I may try my hand at building one. I've never soldered anything in my life but it's time to try.
Jim
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Jim, I run these engines balls to the wall and they restart immediately.I If your not getting quick enough restarts due to overheating I would look into opening that venturi which I would be doing anyhow unless they have a restriction on size. Seeing you had that one made, what did the maker base his size from? That engines isn't available as a control line engine. Modern engines are not like old iron. If your engine doesn't want to cooperate, dowse the engine with water or use a soaked wet rag when you pit and immediately grab the head. We do it all the time with engines and they immediately restart. I personally use fuel but then again, fires can happen. Our last racing contest is this Sunday Nov 16. We have Fox sport race and clown both sportsman and fast. Ken
Ken Cook- Top Poster
- Posts : 5476
Join date : 2012-03-27
Location : pennsylvania
Re: Racing Mongoose
Ken,
I've not tried a practice pit yet. Four of us are getting together next Friday to practice, I will run it balks out and see what happens.
The venturi internal diameter is the same as an L.A. .25. Rules allow for unmodified .25s only, that's why we went with the L.A. .25 sized venturi.
I'll try and get video of a practice race.
Jim
I've not tried a practice pit yet. Four of us are getting together next Friday to practice, I will run it balks out and see what happens.
The venturi internal diameter is the same as an L.A. .25. Rules allow for unmodified .25s only, that's why we went with the L.A. .25 sized venturi.
I'll try and get video of a practice race.
Jim
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
What confuses me here and it's more than likely the rules that I'm dealing with over here is the fact your running plain bushed engines against BB engines. Venturi size will give you a bit more power, but it will also cool the engine a bit more. More fuel equates to more power. The term modified would be questionable to me at least in this event. You already modified the engine by making your own venturi due to it not coming stock with one. A larger venturi may give you a slight power edge, but it's also going to make your fuel economy go down. You need to find a balance between prop and venturi and lap times to suit the event. Most LA .25's I believe used a .265" venturi opening on the .25's. However, I have had some larger as much as .273". They have variables and I certainly wouldn't feel that opening your venturi wouldn't be constituted as cheating. Ken
Ken Cook- Top Poster
- Posts : 5476
Join date : 2012-03-27
Location : pennsylvania
Re: Racing Mongoose
Ken,
It's a new event and the engine choice rules seem a little loose. At the meeting Tuesday a long time and very well respected club member said my engine wasn't legal. We reviewed the rules and it's ok. That will change if the BB .25 guys start creaming the fox guys, and rightly so. My understanding is that the Brodak .25 is the hot engine for SSR. I will get one if the rule changes. I also have a new Fox .35 that is super tight but I don't want to abuse it on a race plane .
Jim
It's a new event and the engine choice rules seem a little loose. At the meeting Tuesday a long time and very well respected club member said my engine wasn't legal. We reviewed the rules and it's ok. That will change if the BB .25 guys start creaming the fox guys, and rightly so. My understanding is that the Brodak .25 is the hot engine for SSR. I will get one if the rule changes. I also have a new Fox .35 that is super tight but I don't want to abuse it on a race plane .
Jim
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
I have never understood why you just can't have a .25 class and open it up to mods. Seems to me that you could really have a good competition that way.
Anyway, the Mongoose is smokin' Jim! I hope you win with it!
Have you considered walking with the plane? All the speed stuff I have watched, the guys in the center walk around as opposed to standing still. Not sure if it helps anything, but they all do it.
Ron
Anyway, the Mongoose is smokin' Jim! I hope you win with it!
Have you considered walking with the plane? All the speed stuff I have watched, the guys in the center walk around as opposed to standing still. Not sure if it helps anything, but they all do it.
Ron
Cribbs74- Moderator
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Posts : 11895
Join date : 2011-10-24
Age : 50
Location : Tuttle, OK
Re: Racing Mongoose
It's not pretty but I broke down and built my own race tank. It performs flawlessly, even rpm till the very end and 37 lap runs. And yes, the tank started life as a Colman's mustard tin!
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Looks good to me Jim! Good job!
Cribbs74- Moderator
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Posts : 11895
Join date : 2011-10-24
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Re: Racing Mongoose
Awesome Jim! I was hoping you'd give soldering-up a tank a try.. and it ended up being a success! I'm sure you'll build more if you like it as much as I did, after the first time.
That's a cool class.. even with the red tape involved. They'll settle on something soon enough.. and you'll have something that works.. I'm sure.
That's a cool class.. even with the red tape involved. They'll settle on something soon enough.. and you'll have something that works.. I'm sure.
Re: Racing Mongoose
Nice Job Jim , Looks ant ever thing if it works and serves the purpose that's good enough , I like the way you have it plumed as best I can tell, I don't think there is no way it cant work with the outlet on the bottom . I have a question , why did you decide to put the pressure line on the bottom as well / instead of the top? Eric
getback- Top Poster
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Posts : 10138
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Location : julian , NC
Re: Racing Mongoose
Eric,
I put the pressure line next to the feed so it acts as a uniflow. I saw the idea on this thread over at Stunthanger:
http://stunthanger.com/smf/index.php/topic,25610.0.html
Jim
I put the pressure line next to the feed so it acts as a uniflow. I saw the idea on this thread over at Stunthanger:
http://stunthanger.com/smf/index.php/topic,25610.0.html
Jim
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Today's lesson:
Always always ALWAYS check to make sure lines aren't reversed before launching!
Always always ALWAYS check to make sure lines aren't reversed before launching!
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Oh dear!
It looks like the spinner and the propeller took a battering but is the engine OK?
It looks like the spinner and the propeller took a battering but is the engine OK?
ian1954- Diamond Member
- Posts : 2688
Join date : 2011-11-16
Age : 69
Location : England
Re: Racing Mongoose
Jim, that's horrible. One way to stop that from happening again is to use colored heat shrink tubing on your line sets and leadouts and handle. Anyone in control line has visited that destructive path. Ken
Ken Cook- Top Poster
- Posts : 5476
Join date : 2012-03-27
Location : pennsylvania
Re: Racing Mongoose
Ken,
Great idea on the heat shrink. I think most of us on the forum have learned that the most painful lessons are also the most valuable. I will check control direction on every preflight from now on.
Ian,
The crankshaft is bent and a mounting lug was broken:
I already have a new engine on order . The plan is to put the already broken in piston and liner in the new engine and mount it on this model:
https://www.coxengineforum.com/t7618-racing-super-clown-build#95939
Great idea on the heat shrink. I think most of us on the forum have learned that the most painful lessons are also the most valuable. I will check control direction on every preflight from now on.
Ian,
The crankshaft is bent and a mounting lug was broken:
I already have a new engine on order . The plan is to put the already broken in piston and liner in the new engine and mount it on this model:
https://www.coxengineforum.com/t7618-racing-super-clown-build#95939
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Boom!!
Dang Jim, you made a mess of that thing. Welcome to the busted crank club
The Clown should make a great racer. Small, light weight and thin airfoil. Can you modify the plane?
If you can add a streamlined nacelle that would look sweet and sleek!
Ron
Dang Jim, you made a mess of that thing. Welcome to the busted crank club
The Clown should make a great racer. Small, light weight and thin airfoil. Can you modify the plane?
If you can add a streamlined nacelle that would look sweet and sleek!
Ron
Cribbs74- Moderator
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Posts : 11895
Join date : 2011-10-24
Age : 50
Location : Tuttle, OK
Re: Racing Mongoose
Sorry Jim.. not sure if you're into naming your models.. but if it were me; in memorial of the Mongoose, I'd name the new model "Tears of a Clown".. but that's just me being me. Good luck with the new build.
Re: Racing Mongoose
Ron,
The model can be modified to "add strength for racing". I plan on adding a 1/8 hard balsa inboard tripleler and an additional nacelle to fair the 1 3/4 spinner into the fuselage. I will also sheet the leading edge back to the spar and go with a single wheel landing gear.
Jim
The model can be modified to "add strength for racing". I plan on adding a 1/8 hard balsa inboard tripleler and an additional nacelle to fair the 1 3/4 spinner into the fuselage. I will also sheet the leading edge back to the spar and go with a single wheel landing gear.
Jim
JPvelo- Diamond Member
- Posts : 1972
Join date : 2011-12-02
Age : 56
Location : Colorado
Re: Racing Mongoose
Sorry to see Jim
Looks like the plane hit the deck really hard. Glad you got a new engine on the way.
Theo
Looks like the plane hit the deck really hard. Glad you got a new engine on the way.
Theo
Theo Kleynhans- Gold Member
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Join date : 2013-12-30
Age : 42
Location : South Africa
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