RE: Boomerang Sprint Build Thread!
 

Hi Joe,

The Sprint was my 1st Turbine as well and now I'm starting the Elan. I know $ doesn't grow on trees so I will address a few of your issues. The 1st thing you need to understand is in the Turbine world, you cannot be "penny wise and dollar foolish". Living in Chicago like you do, time is slowly running out for the flying season. If you don't plan to have it ready for this season, just kick back and do the ship right. The Sprint is one of the best designed ships out there, but, there are mods that need too be done. Read all the threads here for the Sprint and you will gain some great knowledge. That's what I did. OK. some of your questions I can help you with. !st, there is no hopper tank, just the UAT. As far as the Alum tape, you don't need it. With the proper allignment of the Turbine, I'm using a P-80, heat should not be a problem on the front of the stab. What I do recomend is to use BVM Heat Shield Paint in the Turbine area. As far as the BVM Smooth Stop, great brake valve but so is the Jet Tronics. Dreamworks, as you know, designed several LG packages for the Boomerang series. They all include everything you need. It's a great package and I have had great sucess and super support from Todd and Linda. As far as your 4" main wheels, the Sprint is not designed for them. You can see that by the wheel well covers. Although the instructions don't show it, there is a right and a left on those covers. You can get plenty of support from many people on this thread. Take advantage of it. It will same you many hours of problem solving and many dollars in the long run.

Have fun,

Doc...;)

RE: Boomerang Sprint Build Thread!
 

Hi Joe,

I just finished building my Sprint with the help of a professional builder. Not that the plane needed it, I'm the one who needed help ;-)

I don't quite understand your question on tires, so I'll try to answer with what I did with my "master's" help:


Is your first jet the KingCat? I believe it flies a lot easier than the Sprint... from all I've seen and heard.


In my build I made the booms and wings removable so I can carry them in the car, and I did glue the center wing to the fuselage so the retracts and flaps remain attached all the time. What I used was:
- Elevator - 36" extension
- Rudders - 24" extensions
- Aileron - 12" extensions
- Flaps - 24" extensions

These extensions above will get you to the connecting point on the center wing that connects to another extension set which goes into the receiver. I mounted my JR1221 up front on the radio tray, so I needed a set of 5 x 24" extensions that bring the signal from the receiver to the exit points on the center fuselage. The NWS servo is under the receiver, I didn't need an extension. The flap goes straight into the receiver through the 24" extension. A 12" extension will not reach the center wing exit point if you mount the receiver up front the radio tray.


This very loong thread has mostly builders who used BVM UAT or the UAT that Patricia sells. I didn't see anyone with a standard header tank. Turbines don't like air bubbles and simply stop if they find one. The UAT is cheap insurance against a dead stick landing. Use safety wire in the tank connections, internal and external, or fuel line clips.

I can't see why. Note that I used the included radio tray as a template to build my own radio tray since the original tray has a lot of useless holes. I used JetTronics but there was ample room for a BVM smooth stop or the UP valves that come with Todd's standard retracts sets.


Aircraft Spruce is where I got my tape.

I got Todd's De Luxe set and I don't regret it. The difference to the standards is just the JetTronics versus UP's valves. They both work, it's a matter of personal preference. The retracts are more expensive than the plane in this case, but I believe they will outlast the plane specially because you'll be bouncing a lot on your first landings. The landing speed is reasonably slow, but it's still fast enough to rip out cheap retracts and their mounting blocks.

Others may correct me if I'm wrong, but the ProLynx retracts that Todd sells will support any plane in the Sprint's weight range up to a 20 lb (9kg) plane. So you may reuse them in your 3rd plane.

Hope it helps. Good luck

Hermann

RE: Boomerang Sprint Build Thread!
 

Normally the last fuel line going to the turbine is 4mm festo tube, it there a fuel filter that fits this or is it just a case of heating up the tube and pushing onto a normal fuel filter nipple

RE: Boomerang Sprint Build Thread!
 

Festo and JetCat both make an inline filter to fit 4mm tubing, Festo also make a fitting to convert 6mm Tygon to 4mm festo, have a look for your local Festo stockist on the Web, its supprising how much they do that the normal hobby shops don't carry on the shelves.

MIke

RE: Boomerang Sprint Build Thread!
 

An inline filter to fit the 4mm tube is interesting, you dont have a festo part no. ? I have found thing very difficult to find on some of the festo supplier websites.

The more I think about it your suggestion to fit a filter after the pump is a good one and I want to fit one on my wren powered boomerang

RE: Boomerang Sprint Build Thread!
 

If you are having trouble getting them, Als hobbies Jet Center have them on the Festo page may be easier and quicker too.

Mike

RE: Boomerang Sprint Build Thread!
 

thansk guys for your answers.

yes the KC is my 1st jet. i put 8 fligthts on it last year and 8 in one session this year. i know that i can get signed off on it but since that will be more difficult to string a few more days together to do that, and then if i didnt fly it again right away i would not feel comfortable with it, therefore the Sprint

the KingCat is a great flying plane but absolutely more difficult to land than the Sprint. and its 10K vice 4 to 5K for the Sprint. plus you can fix the Sprint vice order a new wing or boom on the KC. i love the KC but that will be next years plane.

thanks on the Smoothstop info. couldnt tell.

Doc, i will get this up in the air this year. i fly late in the year and early in the year. we have a 50x800 paved runway so we can fly pretty easiliy year round.

as for the wheel sizes, yes i know that 4" wont work, i was just referencing the INTAIRCO 4" wheels i have for my 3rd Jet,, a Comp-Arm Lightning with all of Todd's gear. i am very familiar with Todd's stuff. it wasnt trying to go cheap, just less expensive. if Alan says its ok on 3/16" wire struts, i figure he is the designer he would know.


as i am crunched for time (just this weekend and next to assemble0 i will probably go with Todd's gear. as for bounced landings, i think that since this plane lands at 1/2 the speed of the KingCat i don't think i will be really too worried about bounced landings. we'll see!!!

again, thanks for the input. i did read all 26 pages of posts on this thing. i think i have it planned out how to get it done.

RE: Boomerang Sprint Build Thread!
 

ok, one more question

i have a spare KingCat CF engine mounting plate. since some recommeded raising up the P-80 to center with a 3/8" spacer, i was wondering if i could use the CF plates as taht spacer. mounting the turbine to the CF then the CF to the plane.

thoughts?

RE: Boomerang Sprint Build Thread!
 

bit the bullet and just ordered the Dreamworks gear .. should all be there by friday. build time

RE: Boomerang Sprint Build Thread!
 

my friend this plane lands as slow as a trainer. only thing you dont want is to get behind the power curve on landing. this plane has a high wing loading like all jets so you will need to keep speed up until you made the runway. you cant just cut cut power on this plane and glide in. everyclick of throttle you you pull back you can watch the plane sink. flaps are very important on this plane. i land with full flaps and crow. the ground speed is very slow and the plane will stop dead with brakes at 50 feet on the paved runway..very easy plane to land..

RE: Boomerang Sprint Build Thread!
 

Hi,

I'm not familiar with that mount as use the JetCat mount. Your right about seeing the suggestion about the 3/8" shim. I added it but had to remove it so as not to burn the leading edge of the stab and the servo cover. After removing the shim, there have been no more heat issues.

Doc...

RE: Boomerang Sprint Build Thread!
 

Hi
Your Wreen has a filter build into back on top of the compresser,if you lock trough the fad guard you will see it.

all the best with your new toy:D

regards

Andreas

RE: Boomerang Sprint Build Thread!
 

HI Mojo,

We've been on the road for the last 4 weeks going to model meets and taking my grandson to Oshkosh, so I haven't been keeping up with the thread......

The cockpit detail was made up of cockpit kit parts from my distroyed BVM T-33 airframe. and I wraped a peice of cardboard, covered with black paper, over the instrument panel to change the shape.
the Pilot is a F-86 pilot doll that used to be available. I made my own instrument faces for the panel....

I now have 78 flights on my Sprint........................and loving it!!!!!! Thank you Alan

Paul

RE: Boomerang Sprint Build Thread!
 

Hello Paul, sounds like a fine program to me... I have been to Sun & Fun many times but not yet to Oshkosh, hopefully in the near future... Well compliments again on your fine looking bird and Super looking cockpit work... Alan & Patricia are super people, I was fortunate to spend 3 days with them at JetPower 2007, we had a Blast...Good Fun...
OK Happy Flying and I hope to enjoy a Sprint soon as well...
Take Care
Mojo

RE: Boomerang Sprint Build Thread!
 

Can you guys please post some AUW figures for your Sprint? I'd like to compare to mine. Especially interested in hearing from anyone with a P80 setup.

RE: Boomerang Sprint Build Thread!
 

What is the best type of servo to use for the nose gear steering? I am thinking that an HS-625mg would be a good choice but do I need metal gears? I would appreciate any insight gained from experience.

RE: Boomerang Sprint Build Thread!
 

If you are using closed loop steering, don't use a digital unless you leave the cables slack, as it will constantly hunt for center and will just use power, leaving the cables slack does not seem to matter if you are using a trailing link leg it self centers and steers in a straight line by itself this also puts less strain on the servo gears so metal is not rearly needed. I use whatever Analog standard servo I have to hand, never had a problem yet. Oh yes I fly from a very bumpy sheep poo infested grass pasture, so my UC tends to take a beating.

Mike

RE: Boomerang Sprint Build Thread!
 

My Sprints weight is 18 # 4 OZ. with a P-70 for power.......because the P-70 is stingy with it's fuel I usually only cary 96 ounces for a flight of 8 min...........with plenty left for a go around, or waiting to land. The 96 ounces weighs 5 # 2 ounces so take off weight is 23 # 6 oz.

I have the Tank graduated at 32, 64, & 96 ounces so I can keep better track of the amount of fuel I'm using.

This combination works just fine, as will the P-80, I'm sure.

Paul

RE: Boomerang Sprint Build Thread!
 

i get 13 minute flights with the p70 with fue to spare. thats not to bad.. i am using the j tech split tank.. i think the p80 is a little more thirsty..

RE: Boomerang Sprint Build Thread!
 

No Kidding! I use nearly my full 3.8L in around 10mins. I am power hungry though[:@]. Will weigh mine this weekend, interested to know where I'm at

RE: Boomerang Sprint Build Thread!
 

P-70 + left stick in the ON position = 6 min till UAT is dry.

RE: Boomerang Sprint Build Thread!
 

you must be flying wide open alot. i do that to . i was giving a conservative time amount. no fun flying these things slow though is it.hahaha

RE: Boomerang Sprint Build Thread!
 

I just ran into this problem when trying to install the Dreamworks Pro-Link nose gear in my Sprint. In order for the gear to fully retract, it must sit at the front edge of the landing gear mounting blocks (see picture #1 below). Apparently this was the original design. My Sprint, however, has a bulkhead at the end of the mounting rails which will not allow me to install the nose gear as shown. Has anyone else run into this problem? My solution would be to trim the bulkhead (see picture #2) to allow the gear to be installed but I am wondering if this would weaken the structural integrity of the nose gear mount.

RE: Boomerang Sprint Build Thread!
 

my left stick has two positions, Land and FUN!!! :D


jblloyd, you can trim that area if necessary, the forces from landing are toward the fuselage there not away from it.

RE: Boomerang Sprint Build Thread!
 

IMO the easiest solution would be to move the gear towards the nose and mount it on a 1/4" ply packer or whatever is needed to allow the steering arm to sit down beyond the packer, you then have the perfect bulkhead to guide the steering cables through, the extra positive incidence will only help on take off and should not make any difference on landing.

Interesting disscusion on fuel consumption, I had a P80 in my Elan and would use nearly all of my available 2.5L in a 7 min flight, since installing a P120 I can fly for 9 mins and still have some left in the main tank.

Mike