jfetter

OK, #1, stick with standard bulkhead. As for cooling, I used their pics as a guide and didn't see extra holes. I also think the airflow around the bulkhead will be sufficient (not to discount your opnion, I fully intend to measure temp after first flight but my experience with outrunners to date is they don't generate a lot of heat since the moving "can" helps to dissapate).

#2, yes, glad you cleared this up, I'll likely ust buy a short peice of 12mm carbon tube.

#3, glad to hear you use this, who wants long slots?

#4 (commented on seperate post).

So to clarify the vibration dampening on the motor, you didn't use the 2-plate method they show for the pletty?

Thank again!

Jack

Malcolm H

Actually Jack the hinges being deeper at the bottom effectively angles the hinge line such that rudder gives up. In reality this effect is tiny. In the early days of pattern flying the hinge line was often angled markedly to try and counter the pitch down caused by rudder deflection on many designs to little effect. CG position and height of the stab being much more potent in this respect.

Malcolm

Malcolm H

No the Plett carbon mounting plate and rubbers are still in my spares box.

Malcolm

jfetter

Hmmm, I would have thought this pre-fab mounting hardware would have been used, I think it's nice they even considered us electrics when they built this kit.

I was able to get the motor mounted last night, I'm gonna' keep the vibration dampening system in place for now, at 1.5 ounces it's light, seems efficient (bending the motor back and forth) and who knows, might end up even liking it...

Jack

jbrown

My Feedback: (12)

Jack, et. al;

I also have an Impact with the AXI 5330-F / Jeti 90 setup. Everything your reading in these posts is absolutely correct.
I didn't use a soft mount; simply the CF firewall and rubber gromets - no vibration (prop balanced very carefully).
I opted to use a balsa crutch along with the foam one supplied. Paranoid about a fuse failure I guess.
IMHO, the rudder set up was the most agonizing. I opted to install the fin post in the fuse first, then the previously hinged rudder. So far so good. BUT, make sure you have enough rudder travel BEFORE you glue it all together.
The plane flies like a dream and am looking forward to flying it in competition this year.

Now the bad news, with 2-TP5300's, a battery tray and rudder servo tray that are admittedly over-kill, my plane weighs 11lbs 14 oz. Hope it never gets weighed! But the extra weight does not seem to adversely affect the flight quality no matter what speed the wind is blowing.

Best of luck, Jim

jfetter

Jim,

How does the AXI pull, powerful? What prop are you using (beleive it or not, MotoCalc shows an 18 x 8 as the ideal prop for my setup, logic says not big enough but MotoCalc has served me very well to date with predictions)? Also, I assume you are flying 10S, do you find you have as much power as you need/want? I did the math on your setup and (assuming you are running 10S), you'd have to shave 7 oz per pack from your setup (hard to do). You can accomplish this with 2 x EVO 5S 2500 packs but then your capacity is now half, not sure you can complete the pattern.

I am not a good enough pilot to compete now, I am building this one to learn to fly better and what the heck, it's an awesome looking plane! I expect mine to come in around 11.5 lbs, I should have the final weights by Monday after I install the electronics. I guess I'm lucky in that I get an awesome plane and I don't have to struggle with the weight.

If you had to do it again, would you still install the fin post the same way you did the first time? I can't help but think it is easier to do (your way) because you can absolutely get a solid glue joint this way (versus having to assume the joint is properly glued and worrying about getting epoxy on the hinges, etc)...

Jack

jbrown

My Feedback: (12)

Jack,

The AXI Pulls my overweight (LOL) Impact like a tractor, unlimited vertical. Are you aware the weight limit for competition pattern planes (2 meter planes) is 11 lbs? The good news is no one weighs them. At least not at local contests.

Yes, I'm using the TP 5300 packs in series (10S). I'm on the look out for lighter batteries, but my 5300's only give me 10-12 mins. of flight time now, not really enough to get a good practice session in.

Prop is an APC 21x12. But I'm going to try a smaller diameter with more pitch as soon as I can, say a 20 (or 19) x 13-15. Just to compare, and see if the plane will penetrate better without increasing the speed too much.

Yes, I would install the rudder / fin post in exactly the same way. Like you say, it's a much better glue joint. After gluing the hinges into the fin post, I also hung the plane from the nose when the glue was drying. My theory was that the glue would puttle around the end of the hinges (inside the fin post) providing a little extra adhesion. And whatever you do, MAKE SURE YOU HAVE ENOUGH RUDDER TRAVEL BEFORE YOU GLUE THE RUDDER ON! Measuring from the tip of the fin (front) to the tip of the rudder counter-balance, I've got 1-5/8 in. travel (each way). This is BARELY enough travel to get in a reliable stall-turn. You should try to get 1-3/4 to 2 in. of travel if you can.

You do know about putting a little light-weight oil on the pivot point of the hinges, right? Just enough to keep any errant epoxy out of the hinge joint, and be careful you don't get any oil on the hinge posts as the epoxy won't stick.

Don't be afraid to try a pattern contest. The Sportsman class would be the starting point, and you'll get lots of help at a contest if needed. But you'll need to practice the sequence until your sick of it before going. Just jump in!!!

If I can help further, send a post or PM.
Jim

mups53

My Feedback: (41)

I'm running an AXI F3A on my Impact. We've found the 20 x 13 APC to work very well with the 5300 pack. Mike
We're tesing a Hextronic motor now that is showing real strong #'s for a price that will blow you away. Mike

jfetter

Wow, what a sad thread, of course entirely my fault! ;-)

It's been a long time since I've cleaned up my airplane room, I was in there the other day and as I was moving stuff around, I pulled out the Impact fuse (no more complete than the previous posts) from the closet and thought "man what a pretty plane!". So after cleaning up the room, I got all the Impact parts together, all the electronics, everything needed to finally finish this puppy and off we go!

I guess I should start out by saying I got quite busy at work last winter and slowly got more into work than R/C, it's a cyclical thing, I'm sure many others go through. In my case, the time needed to finish the Impact against my already scarce time to fly, had me put the thing away in favor of a Fliton Inspire 60 (e-powered) that was ready to go. Enough time lapsed that I really forgot about it (not entirely, it was always standing tall in the closet, mocking me at 30% completion) and moved onto a few other projects like a Align TRex 450 SE, a hanger 9 Sundowner (with the same Axi 5330/F3A, Jeti Spin 99, FlightPower 12S 5000 & Mejzlik 20 x 12 carbon prop I plan on using on the Impact) and finally an Align TRex 600. Well after cleaning up the hobby room and deciding enough with the wanna' be pattern planes I have, let's get serious and finish this thing!

So I started this past Saturday, I lost a little time when I ran out of Aeropoxy only to find out the manufacturer had some issues and have since halted shipping. After a little coaxing by my LHS guru, I switched over to BVM's new V-poxy which so far, has the same rock solid holding power as Aeropoxy (with half the drying time). In any case, I've been able to get the stab tubes lined up, drilled and glued, the addendum bulkhead glued, the addendum stiffener inside the fuse glued, the stab tubes sanded and fitted to the stabs, the stabs cut for the servo arms, the stabs reamed to slip a mini servo inside, the rudder notched and the 4 hinges glued along with the rudder horn, the rudder post glued in the fuse, the chin cowl pinned and finally, the canopy painted, fitted, pinned and latched (whew!).

My next step is to glue the completed rudder/hinges to the rudder post, make 2 servo mounts for the stabs, drill the stabs, mount the tail wheel and the back half is done! I expect to then mount the wing servos (still puzzled how a 24" duct-taped screwdriver will feel), sand the rear wing pins, drill and tap the wings for the nylon bolts, mount the gear and finish the chin cowl mounting. I expect if I keep at it, I can be done by the weekend for a maiden next Wednesday (December 19 if all goes well). I still have to come up with a decent way to mount the batteries, I want something quick and well engineered, not an after-thought like some of my e-planes. I also plan on using an arming switch, I've had great luck with them, nothing like sitting on the flight line patiently while others fiddle with their idle speed and mix only to arm the plane in 2 seconds and taxi out ;-)

Some things I didn't do that were recommended, 2 things come to mind. First, I didn't use incidence adjusters on the wings or stabs, mostly because I couldn't locate any, that and the fact my flying skills wouldn't likely notice. Second, I used aeropoxy exclusively for all glue joints rather than epoxy with micro balloons as recommended. I am not worried about weight because I never plan on competing with this plane and if I do, I'd likely change out the LiPo capacity to cut weight but also because I want the glue joints to not be the part that fails. The only exception was on the addendum fuselage stiffener which was difficult to glue conventionally so I used epoxy and waited until it was hot and allowed it to run into position all the way down the inside of the fuse.

One final note, I mentined before that I built a Hanger 9 Sundowner recently using the same setup as I plan on using with the Impact, if anyone is curious, here are the bench numbers for the powerplant;

Components:

Axi 5330/F3A
Jeti Spin 99
2 x 6S2P EVO 5000 20C
Mejzlik 20 x 12E Carbon

Bench tests with a whattmeter and RPM check;

3,650 Watts (315+ watts/lb. for the Impact!)
81 Amps
7,110 RPM

I really have the bug to get this Impact built, I am dying to fly it!

jfetter

I've been able to get the back-end wrapped up. I glued the rudder post in the fuse with V-poxy, I didn't clamp it tight because the fuse seemed to be in the correct place, maybe 1/8" of space around the post for a good bead of glue. I got the rudder glued in as well after the post cured, cut out the rudder pull-pull wires and mounted some nice exit guides, fabricated and mounted a rudder servo tray with room for the RX, routed and pre-fastened the servo wires in place, mounted the CF landing gear, getting close to being done, I'd say I'm near 85% or so.

The remaining steps are fairly easy, mount the wing servos, sand the wing pins down a tad for easier fitting of the wings, finish the chin cowl mounts, re-mount the motor (removed while I made dust), mount the ESC and come up with a good battery mount after setting CG. So far it's been a fair amount of work, I won't lie, I would have preferred this stuff was all completed like most ARF's today. I suspect they billed this as "set it the way you want it" or maybe this early generation of composite planes simply didn't warrant them doing this much as it would take them the same 40+ hours it has taken me, not sure but I know in the end I saved $$$ so I suppose that's not a bad thing.

Mistakes, there is one and looking back I don't know how I would have avoided it the first time since the manul is little help and no pictures are there to clarify. I mounted the rudder hinge pins a little too far forward of the correct pivot point. What I mean by that is looking at it now, the pivot point should be inside the radius of the rudder, I glued the pins so the pivot point was at the edge of the radius, making the rudder need to be mounted a little futher back (more gap) then it could have been to have proper clearance. This is a minor cosmetic issue and I doubt it will have any impact (no pun intended) on the flying characteristics but still, it would have been nice to see an image in the plans with a dotted line signifying the hing pivot point. I could easily cut the pins, drill them out and re-attach, just not in the mood after it all came out so well (with the exceptin of the position of the hinges).

Here's the latest pics...

Jack

jfetter

Almost done now! I've been able to get the AXI 5330/F3A motor and other electronics completed, I opted to use 2 VHVBec's (Very High Voltage) in parallel with the JR 2.4GHz RX. I've been using BEC's exclusively the past year and a half the only issue here was finding ones that could handle 12S, which these new VHVBec's from Dimension Engineering can handle. I mounted the Jeti Spin 99 on 3/4" standoffs to give it ample airflow, this should do a good job of keeping it as cool as possible. The chin cowl and canopy have been mounted, I have to say I found this the most tedious of all the little things that were not completed out-of-the-box, lining up the carbon pins and the sleeves plus sanding them really isn't a job that I found remotely enjoyable. Any future composite plane I buy needs to have this stuff completed already! I aso painted the canopy, I decided to try fish-net stockings to give it a scaled appearance, I think it came out pretty nice, I completed it with a faded shadow border to give it better 3 dimensional qualities.

Well, nothing more to do but mount the wheel pants, wing servos and fashion a battery tray. I am leaning towards using 2 carbon rods in the fuse and make the battery tray so it slides in past the forward tube, drops down and "hooks" that tube when pulled backwards again. This would make an easy in-out solution as all you'd have to do to fasten it would be pull it back and velcro to the rear tube, this should prove interesting and quick if it works. I have a Mejzlik 20 x 12E CF prop, I'll mount it after I get everything else completed and do a run-up with numbers posted.

Getting excited!

Jack

jfetter

Finished!

I can't believe it, it seems like this one took forever (I am not used to spending 60 - 70 hours on a plane) but it's done! I am very releived and very, very happy, I've been looking at this thing in it's various parts piles for almost a year, time to fly!

I was able to get the servos mounted much easier than I thought, the wings proved to need only a trivial amount of trickery to get the servos installed, not as bad as I originally thought. I also glued 2 carbon tubes in the fuse to support the batteries, I was able to fashion a battery tray from 1/4 birch ply with lightening holes. I used some wood to form a "U" that hooks over the front carbon tube and then some wood in the rear with a very slight curve cut into it so it snaps into place, very effective. The battery tray is designed to hold 2 of the EVO 5000 6S2P 20/30/50C packs and by being long, it can be adapted to almost anything. An arming switch was mounted just above the right wing, I am a huge fan of these things and any plane that doesn't have one should, easy to arm right on the flight line. What else, canopy front nylon bolt was installed, it really does add just the right amount of pull down when you push the canpoy forward, I came close to omitting it but I am glad I didn't, should be virtually impossible to yank the canopy off in flight.

The wheel pants were a pleasure to work with, for once someone includes parts that are proper for the size wheel that should be used, no cutting! They were quite easy to fit and only needed holes drilled on one side (prettier install), I used DuBro 2 1/2 low bounce wheels since my landings are sometimes a tad harder than the proverbial butterfly landing on a leaf scenario. Those of you concerned about weight here we go, the AUW is 11 pounds 8 ounces. My completed Impact came in more than 11 pounds yes BUT remember I am running this on 12S with second generation EVO packs, turns out if I swap out the 2 EVO 5000 6S2P packs (at 28 oz. each) with 2 EVO Lite 5350 6S packs (at 21.5 oz. each), I would have an AUW of 171 ounces (or 10.625 pounds) which would keep me under 11 pounds by some 5 ounces. Truth is I likely will never compete but a flying friend has been bugging me to try so perhaps I might, never know but glad to know I can swap out the packs and make weight.

The next step is the maiden on Wednesday (12/19/07), I plan on having my local instructor test it like I do with all my planes, probably mental but I've been doing it so long it wouldn't feel right any other way. I'll certainly post results after the flight, everything I've read has me almost giddy with anticipation. I'm going to use the new JR 9303 2.4GHz, I also have a Spektrum DX7 so I'm used to the 2.4GHz systems but the 9303 really is a dream to program. Setting up dual ailerons and dual elevators couldn't be easier, once setup the radio even changes the names so when using sub trim you can tell what your adjusting. The Impact manual talks about adding 10% aileron differential (negative) to account for the top hinging, that too was a breeze to setup with the 9303 (it has aileron differential right in the setup, doesn't need flapperons either, just dual aileron and/or the flapperon configuration). Well, nothing left but to fly...

Jack

jfetter

What can I say, it flies as well as it looks! It took me a little while (3 flights) to get comfortable with the power, at 12S it has plenty of reserve and you can comfortably fly at a few clicks above 1/2 throttle. Lines are straight and true and it really reacts nice to control movements. Like others have noted there is a slight pull to the canopy on edge but easily corrected, I have a little more up trim then I'd like, still playing around with CG but so far it flies like it's on rails.

My overal impression is this is a winner, paying only $650 for a $1,500 pattern plane that is a few years old was a bargain, the only drawback is the amount of work required to complete it. After taking a look around at current models, most are 90% ready to go, with wing tubes, alignment pins and such all pre-drilled and mounted. Though this may seem a small detail, spending 70 hours of time you may not have can be expensive if it comes at the expense of something else you could be (or need to be) doing, the bargain is in the eye of the beholder so to speak.

Would I do it again, yes, if nothing else to make it 100% perfect and this time mount incidence adjusters on the stabs per Malcolm's recommendation. The work really gets tedious, especially fitting the carbon pins in the carbn tubes but in the end it's worth it. This plane will go a long way in helping transition my flying skills from intermediate into pattern competition, hopefully it will last years and give me hundreds of flights...

Jack

rcinstructor

Hi, Jack. Just found this thread. You might mention the smoke systems you been using lately. Guys the smoke system makes wonderful dence smoke for 12 seconds (as good as an ICE) and $300. a flight. I have flown Jacks plane and I'll just call it a 2.4gasim.

jfetter

If I bring another smoked ESC in the house my Wife is going to start to wonder! On the positive side Jeti is taking back the smoked Spin 99 no questions asked ;-)

Jack

rcinstructor

Jfetter- I'm glad you mentioned that. I am amazed at just how sensitive women are to the smell of glow fuel, burnt-wireing, and epoxy. All of these I barely notice but my can smell these sents before I get home...... maybe they just detect spent money.

jfetter

Just remember a little rule I live by. All planes cost $100, all of them. Some of them (when you want the same plane in 2 different color schems) are even sold during "2-for-1" sales when you really didn't want the other one but it was free...

;-)

Jack

Bill Carder

My Feedback: (1)

Has anyone built an Impact with a YS 160 with the new Hatori short pipe? I would like to see some pictures if anyone has them.[hr]

jfetter

I'm all electric but I think if you check, you will find at least a few build threads for the Impact, you may find what you're looking for...

Jack

67685

Hi Bill,

My Impact is equipped with 160DZ and hattori short pipe.

Sorry, i have no picture, the plane is stored until summer-season ... Anyway, the installation is straight forward; just add a bulkhead in front of the landing gear to block off the pipe tunnel.

Kjell Olav

Flying Kiwi

Here is mine. It uses the Hattori mounts as supplied sitting on the landing gear mount. Hope this helps

Brian

Bill Carder

My Feedback: (1)

Thanks for the replys, the pictures were just what I was looking for, wasn't sure how far back the pipe would go. Looks like it fits great to the gear plate.

Jeff Boyd 2

Hi Jack . . FINALLY got mine up and running and thought I'd post a few pics . .

Instead of the gussett down the fuse I added 4 strands of Carbon Tow from the wing to the fin post. Made it really stiff. I still fitted the tail formers (after the Carbon Tow) so we'll see how it goes.

Flies great. Just trimming now then ready for competition . . [8D]

Cheers,

Jeff

jfetter

Looks nice! I like the paint!

I do see some differences though, I didn't expect anything would be different though. I see you have moved the rudder linkage but even the rudder itself looks different?

Jack

Jeff Boyd 2

Yes, there are differences . .

After tirelessly reading thread after thread, I decided on some changes. The main changes being:

1/ Made a new balsa rudder and fin post with 'V' shape hinge edge on rudder and fin.
2/ Changed the shape of the rudder and removed the counter-balance. (heard this improves things)
3/ Moved the pull-pull linkages up to roughly the centre of the rudder.
4/ Carbon Tow to strenghten and stiffen the sides of the fuse between the wing and fin post. Four of the strands run start at the wing tube.
5/ Wing adjusters with the rudder servo tray bracing the fuse.
6/ Bolly undercart and pants

JB