stillQ500

140 MPH with a TT 40 ??? Hmmmmmmm, Almost sounds like a stretch but I'll Bite.
At the risk of sounding stupid, If you can get a Q40 to fly 140 MPH with a sport engine (Iassume itwas stock) , why are we spending upwards of $400.00 per engine,just to go a little faster? Was it with a stock muffler orare youusing a pipe. what prop are you using? The Q40 props or something else. Is anyone racing Q40with this set-up?
This should stir a Hornets nest .

Guy Anderson

daven

My Feedback: (1)

Guy,

its not a little faster, its a lot faster.

Q40's are over 190 now and 140 does sound like a little bit of a stretch also. Maybe wind or dive aided....?

sahartman21

As I mentioned earlier, I am building these primarily as a step up until my landing skills improve. I am building four 422 models and intend to race them.

Where the Thunder Tiger 40 powered option shines is for a club that already flies the 424 class racer. You have an engine, prop, and tank already. They will fly on the same fields as the 424 class. Why not build your skills with these models.

Concerning 140 mph, I understand that this was what the radar said. It was not my model. It was flying against a 428 powered Q-500.

They are noticeably faster than the 424 model but not as fast as the 428 class. The exact speed is not relative. The main item is if you are having fun.

Again - I love my 422 class model. I just need a stepping stone to improve my landing skills. These models fit my needs.

DonStegall

My Feedback: (1)

Back in 2001 or 2002 I had a number of the Kangke F3D-30 planes set up with different engines. This airframe was very close to a Q-40 in size. A 402 square inch wing that was 1 3/16" at the root and the fuselage is 4.75" by 2.75". Just a little under the Q-40 size. But effectively the same drag profile.

I put a TT Pro 40 in one of them. I ran a lot of different props. With a 9x6 it was noticably faster than a 424 plane. With a 9x7 it was still faster. I ran the 7.4x8.25 pylon prop and it was a lot faster. I also ran the APC 8x8 and 8x9. You gain top-end speed at the cost of acceleration as expected.

I didn't have a radar gun to check them. But the speed was as fast as a Quickie with a Quickie JETT with a RED JETT carb on it. The carb slows a Quickie down to about 140-150.

When I came up with the idea for Club 40 in 2005, my vision was Club 40, AMA 424, and Q-40 Sport all using the TT Pro 40. Starting with lower building and pilot skills and increasing with each step.

In 2006, myself, Duane Gall, and some others got Dub Jett to make beam mounts for the TT Pro 40 that allow the TT to be switched with the 422 engines. This was so that older Q-40 airframes could be used in Q-40 Sport. Plus new planes could be built with the intention of moving from Q-40 Sport up to 422.

Duane Gall fitted a Polecat with a TT Pro 40 using one of the mounts and found the same thing I did with the speeds.

In the AMA 425 proposal, composite airframes were not ruled out. There are too many older Q-40 planes that could be put to use in Q-40 Sport to rule them out.

But Q-40 Sport is less demanding on airframes and building is making a comeback with MANY people building Seekers and other planes for 424. Now some are building Q-40 Sport planes as well.

gsimclair

Don,

How is it that you have all this technical data in place on all these different planes and set up. amazing that someone at their last showing at the NATS, they were a complete disaster.  How did your last NATS go, did you even complete.  The NATS are coming soon, show up and lets us all know how it's done.  But we all know that is not going to happen cause you will find a reason not to, thats OK, we all know your a fraud and can't fly anything but Club40.  Which is OK, but don't claim to be able to do anything else if your not willing to bring it.

G

luv to race

My Feedback: (1)

sahartman and Don....

1.  Is “this” particular plane in this build thread going to see a 422 engine in the front of it?   

2.  Are you sure the wing is going to hold up to the loads at 180-200mph?  No sure 1/16” skins and the lack of a serious spar will hold that wing from folding? just curious...

3. And with no carbon in the nose of the fuse.  What are the thoughts on the front end holding up to the vibration and power?

Thanks,

Randy

DonStegall

My Feedback: (1)

Randy,

I'm now putting carbon fiber in the nose of all of my Q-40 planes. Scott has talked to a number of people and found that this was a concern for them. I have not increased the price of the kits.

As I have talked to Scott some about this plane while he is building it, I will answer the other questions.

"This plane" is not going to see a 422 engine. It is being built purely for a TT Pro 40 engine and Q-40 Sport.

To build a wing for 422, you would need a serious spar and probably 3/32" skins. So far, everyone who has bought Stinger kits has planned on using either a TT Pro 40 or a sport engine in their plane. If I get anyone wanting cores for 3/32" skins, I will make templates.

DonStegall

My Feedback: (1)

On to the building.

gsimclair

Bring it to the NATS if you can, but I am sure when I say you WONT.

I have flown this and flown that . BLAH BLAH   just another internet racer that can't get out of the basement to see the light.

G

Left_Turn

Talk about getting off subject here, Shheeeeeesh.
Scott, you're doing a great job with the building and I can't wait to see it fly.
As far as the 140 claim. That would be mine !! Yes it was on a down wind run coming at Pylon#2 with a 15 to 18 MPH tail wind.
The engine is a VERYold and tired TT40 with the stock muffler and a new style carb. that doesnt turn alot of ground RPMbut seems to unload very well. In fact the engine hasNo pinch and "free wheels" when you are landing. I need a new piston and liner.
Ihave probably 80+ flights on Stinger and its a ton of fun,

Left_Turn

Ihope Scott doesn't mind me intruding on his build thread. Igot my fuse from Duane Gall , its identical in shape as Don's except that mine didn't have the verticle stabilizer as part of the mold. Duane sent me the Tail feathers from one he had crashed and I just transplanted it onto the fuse. Ishot the fuse with Rustoleom paint because it was the closest match to the yellow monokote on the wings. My wing was actually made from a set of "proud bird" cores , For my spar, Iused a "yard Stick" on edge that was trimmed down and epoxied in the cores then sheeted with 3/32 on top and 1/16 on the bottom and glassed in the center section. Iam using a 6oz. sullivan clunk tank and standard size servos. flying weight is 3 Lbs. /15 oz.

PylonDave

Keep these build threads coming Scott and Don!!! I look forward to reading them everyday!!!



As for Gsimclair, Get a life Dude!!! Your being an anonomus jerk!!! unlike Scott and Don you are not doing anything productive here! Go Away!!

sahartman21

My Stinger will be flown with a Thunder Tiger Pro 40.

It has 1/16" sheeting on top and bottom. There are also carbon fiber strips to reinforce the wing. It also has a carbon fiber vertical sheer (spar) on top of the wing.

My AJ-2 has similar construction and has held up fine with a Q-40 short stroke motor.

I wouldn't put a long stroke Q-40 in a Stinger without carbon in the fuselage. Newer fuselages will come with carbon.

No - I am not ready for the Nats yet, but maybe next year.

luv to race

My Feedback: (1)

If it will hold up to the short stroke engine, I'd think it would be okay with the long stroke.  There isn't too much difference in speed, maybe 5-8mph tops.

The only reason I brought up the my wing question...  Was I've seen 2 foam/balsa wings buckle under compression (many years ago of course). Both wings had a 3/16 wide plywood spar on it's edge, about 20" long layed down in the wing like you did your carbon thing.  And carbon laminent under the skins along the spar line, all the way out to the tops.  Both wings failed on the edge of where that spar ended, out by where the ailerons are.  And both wings had 3/32 top sheeting, and 1/6" bottom.   It could of been a bad build job, who knows?  more of an observation..

looks good sir..

RB 

sahartman21

Its time to get back to building.

I suggest running an engine kill for either the Q-40 engine or Thunder Tiger Pro 40. The logic behind this decision is based that the Q-40 is nominally flown without a throttle. It is all or nothing.

So my models are set up with an engine kill regardless of the engine. This way both type of models land the same way.

sahartman21

It is getting late so I chose to glue some parts in place and go to bed.

The landing gear block can be glued in with epoxy or Shoe Goo. The later is actually more durable and that is what I used.

The area behind the wing is very easy to get to with this model. Some Velcro was glued behind the wing should I choose to install the battery there.

sahartman21

I have used a variety of servos in my models.

For the true Q-40 application the following Futaba servos work well with a 5 cell pack:

Aileron - S3002

Elevator- S9650

Engine Kill and rudder - S3102



For the Thunder Tiger powered version the following JR Sport servos work fine - MN48

If you MonoKote the model it will be light enough that full size servos will work fine.

If you fiberglass and paint the wing, the lighter mini servos are a better choice.

sahartman21

This morning the servo tray was cut out and installed.

The tray is made from 1/8" thick plywood and it was glued in place using Shoo Goo.

6/30/09 Comment - I ended up adding tail weight to get the model to balance. You should locate the servos as far back in the radio compartment as you can. Possibly locate the rudder and elevator servos in the far rear. Then locate the engine servo in front of the 2 servos.

sahartman21

The kit contains a pre-slotted horizontal tail surface.

Some 1/64" thick plywood was traced and installed at the leading and trailing edge.

Thin CA glue was used to hold it in place.

Edges were sanded flush with medium sandpaper.

sahartman21

A Dremel tool and cut off wheel were used to cut the slot for the horizontal tail surface and shorten the tail skid.

sahartman21

Rough shape the tail surfaces with a sharp knife.

Next use some 60 grit sandpaper to continue to shape.

Test the fit in the slot at the tail.

sahartman21

The aileron servo will be mounted similar to that of my AJ-2. It will be on the top of the wing.

Drill 3/8" diameter holes for dowel rods pieces.

The servo will be mounted to the dowel using servo screws.

sahartman21

Tape the landing gear in place.

Drill, tap, and countersink the model for the 1/4" x 20 nylon bolts.

sahartman21

Here is what the model looks like with the wing and tail installed.

Next will be the tail hinges, fiberglassing the tail, and painting.

I can hear the engine roaring already.

sahartman21

Temporarily attach the plans over the tail surface. Use some pins to mark the hinge line and cut lines.

Remove the plans and mark the hinge line on top and bottom of the wing.