H-9 T-34 Mentor ARF.... [Archive]

therotund1

Sep 17, 2003, 10:07 PM

Progress report....

The wing is together. It fought me all the way. The center ribs didn't mate up too well so I sanded them. Both wing joiners fit well. Dihedral is correct. 2 hours invested including double checking the measurements on the wing bolts and aileron interior and exterior opening ribs. It has been mentioned at another site that this could be a problem soooo, measure twice, glue once! Mine is not off as reported.

Test fit into the fuselage presented a new problem. The wing wont seat at the rear. The wing has a flat segment where it meets the fuse in the front of the wing saddle. The corners at the top front of the wing are holding the wing back. I'll need to sand the forward opening about 1/16" at the upper corner. Not a major deal, just a little time.

A few notes about this plane. The covering is impeccable! The wing is fully sheeted too. It has an air of quality about it. I'm still happy.

hooter is a friend of mine, everyone say hello! (waits for "hello hooter") I'm happy to know his first post at RCGroups is a poke at me!:D

He too is an RCU refugee.

More tomorrow! Stay tuned....

Dave,
slow? I got passed by a turtle....

Paul Wilson

Sep 17, 2003, 10:26 PM

Glad to see you here Hooter, take some pics Dave if you can.
good Luck
Paul

therotund1

Sep 22, 2003, 12:36 PM

Is it tomorrow yet? The horizontal stab is curing as I type. The wing is in and bolted down. I missed a measurement.I found that the pre-drilled wing bolt hole on the port side was dead on, the starboard side however was off by 1/4" away from the centerline of the wing. I still like it!

I'll get some pics soon Paul.

Add 1-1/2 hours, total of 3-1/2 so far.... Stay tuned...

Dave,
my fingers are stuck to the keyboard...

therotund1

Sep 22, 2003, 04:25 PM

OK, all is proceeding.... The stab's are in and all of the control surfaces are CA'd and fully operational. Only 2 snags on the horizontal stab.

1) This plane has a single control rod to work two elevator halves. It has one of those typical U shaped rods as a joiner. The clevis attaches to a tang that goes straight down after the elevators are installed. This tang was too close to the port side of the planeso I bent it to the centerline of the fuse. Clevis room and interference with the rudder rod assembly is the concern. After the ele's are CA'd this would be very difficult to do so, check yours before hand.

2) They missed the vertical alignment of the outboard hinge slot on the port side elevator by enough to cause the ele half to noticably hang low. I stuck a spare hinge in the original slot, CA'd it, cut it off flush and broke out the Slot Machine. Presto! New slot!

All is well except I CA'd my sock to the floor!:eek:

I'm still happy with it. Now that it looks like a plane, it looks kinda' stubby. It's cute in a baby bulldog sorta way....

2-1/2 more hours. 5 total so far...

Dave,
stuck to the floor...

therotund1

Sep 24, 2003, 09:15 PM

SCREEEEECH!!!! Stopped! Reason below.

Update.
There is absolutely no fuelproofing done on this plane. No biggie right? Well it's set up for a 2 stroke with the muffler in the cowl so it has a hole in the firewall that the muffler goes in and dumps out on the bottom of the fuse in front of the wing. I made a balsa plate to block this hole off. With the retractable nose gear on this plane, of course there is a "bay" that it retracts into. This bay is also where the muffler ends up so I cant seal it off. Now the bad news. At the back of this bay, the fuel tank hangs out into the interior of the plane and for the life of me, I can't figure out how to seal it off without adding a ton of weight!

My quick fix was to mix up a lot of epoxy thinned with alky and microballoons and start painting! I know it'll get fuel residue in there but, that's all I can see to do to it at this point. Time will tell how well it stands up to it.

Nose gear is on but, the axles that came with the H-9 retracts are too small to fit the strut! I got replacements. I could have drilled them but, I don't trust myself without a drill press.

Time check... 2hours. Total time so far... 7 hours. Still happy but concerned.

OK the Screech part. The Funtana I ordered just as Horizon ran out 2 months ago arrived today! My wife has allowed me to put the T-34 on hold for a bit so I'll give the Mentor a break for a week or so. But, in the words of a certain Californian running for Governor,,, "I'll be back!"

The Dave-inator

;)

rc.hackmaster

Oct 09, 2003, 11:02 PM

hey i have a mentor and love it! i had the same issues as you have had, but the flight of the mentor is all worth it. it does drop the left tip at a stall. not a bad stall but totally managable. it flies straight and true. i installed spring airs and they work exceptionaly well. plenty of room for mods in the fuse. i am now adding electrotek nav lites and mars beacon and landing lites with remote on/off for landing lites. should look totally scale on landing. one thing to watch for is the main gear blocks poping loose after a hard landing. look for a deformation to the outboard side of the main gear. mine made a loud pop on a kinda rough landing. just food for thought on this plane. i still love this plane. btw the hangar9 1/7 scale ww2 pilot looks good in the cocpit and no trimming of the pilot is neccesarry at all. good luck with your t34. i will try to post a pic of mine after the lites are all installed. thanks, hack. btw i am glad that this site is still normal. i hate rcuniverse now.

The_Widowmaker

Feb 10, 2004, 09:52 AM

I just got my T-34 Mentor. So far I am very impressed with the quality of this kit. I have test fitted the wing, canopy, control surfaces, etc..(see image) and everything seems to line up well. The wing appears to join together nicely and the mounting holes seem to be in line. The precut slits of for the control surface hinges are well centered so I dont have any high or low spots on my control surfaces. My only complaint so far is that the covering had guite a bit of wrinkling but these were easily removed.

Factor in the price of this kit and I think its a steal. You get the option of retracts, which I am going to install. I am also going with the Saito 72 4 stroke. Its going to be a few days before I can start constuction. I am picking up the electronics and engine next week and will start then. If I run into snags I will post but so far things look good.

Can anyone suggest a product for fuel proofing? I would think they make something specifically for that.

rc.hackmaster

Feb 11, 2004, 07:38 PM

hey dude looks good. wish mine was in one piece still. did my flaps and they worked great. looked so good in flight and slows down very nicely. but i had a battery go dead and she went in on the first flight after adding the flaps. big bummer. wing is shot but the fuse is not too bad, just the firewall popped out. i will get a new wing in a few weeks and rebuild. have fun with the mentor. you will love flying it. the hack.

daryl

Feb 12, 2004, 08:38 AM

email
sk_teo@tm.net.my

He got one aslo from World Models.

The_Widowmaker

Feb 13, 2004, 12:48 PM

Well I have completed the electronics installation with the exception of retracts which I will probably add later. I get the engine in a couple of days. The only issues I have run into are very minor. One is that the front tip of the rudder was a bit warped. This meant that when the rudder was straight, the tip did not line up with the vertical stab. I ended up cutting back some of the covering, putting a slit, flexing the tip in the direction it needed to go and then dropping some thin CA in the slit. When the CA dried it prevented the tip from flexing back so now its in line. Probaby was a better way but this was fast and it worked. Second is the front wheel. Directions call for two collars and the wheel. Problem here is that the axle was so short it does not accomodate all three. The outside colars locking screw is about half way on the tip of the axle. I don't feel safe with that so Im going to either find some narrow colars or grind these down a bit.

On a plus side, the manual calls for you to grind flat edges at certain measurements on the landing gear for the set screws but the gear in my kit already had these spots so there was no measuring or grinding.

In my opinion this is a quality kit. How it does in the air is yet to be seen. I have the option of setting my ailerons up on two channels (1 each), which will allow me to use them as flaperons. This is controlled by a knob on the radio that will let me set the flaperons to any percentage. Should I set it up this way or just go straight ailerons?

rc.hackmaster

Feb 14, 2004, 10:31 AM

dont do flaperons, i tried this also and i had a minor contact with the ground. it makes the mentor tipstall badly. not recomended. if you want to add flaps you will have to add them in the proper spot. not hard but it takes some time. the inner part of the wing is not solid but built up. i had to add some aileron stock to the inside of my flaps and then add some bracing to the wing where they attach. it looks really good with flaps deployed and slows down nice. try flying with just ailerons for now and maybee add flaps later. but please dont do flapperons you will kill the mentor. i even tried the airbrake function on my t6 radio and that doesnt work well either. i dont think that the wing is designed for those type of functions. but remember to get the proper aileron diferential. this helps the mentor roll properly. do whatever the manual says the adjustments are it flies very nice this way. good luck! the hack

The_Widowmaker

Feb 14, 2004, 11:04 AM

Originally posted by rc.hackmaster
dont do flaperons, i tried this also and i had a minor contact with the ground. it makes the mentor tipstall badly. not recomended. if you want to add flaps you will have to add them in the proper spot. not hard but it takes some time. the inner part of the wing is not solid but built up. i had to add some aileron stock to the inside of my flaps and then add some bracing to the wing where they attach. it looks really good with flaps deployed and slows down nice. try flying with just ailerons for now and maybee add flaps later. but please dont do flapperons you will kill the mentor. i even tried the airbrake function on my t6 radio and that doesnt work well either. i dont think that the wing is designed for those type of functions. but remember to get the proper aileron diferential. this helps the mentor roll properly. do whatever the manual says the adjustments are it flies very nice this way. good luck! the hack

Thanks Hack.. thats just the kind of response I was looking for. I will definitely go with just ailerons for now. Picking up the Saito 72 today along with all the odds and ends, you know the stuff that tacks another $100 on to what you were expecting to spend in the first place :)

The_Widowmaker

Feb 14, 2004, 09:37 PM

I got my engine today. Got it mounted to the engine mounts but when I got ready to mount it to the firewall I found that they did not send blindnuts. Its held in place temp with a smaller screw and blindnut.
Three problems I have found. The steering arm on the front gear in the neutral position is going to hit the cowl. I will be able to turn left but since its already touching at neutral I wont be able to turn right. Since the gear already had a pre-flattened spot on the gear for the steering arm set screw I cannot reposition the arm. I would have to file another flat spot and it has to be at that same height. Im scared that would weaken the gear to much.

Second is the front of the engine mount nearest the landing gear blocks is all but touching the blocks. Its not quite there but you couldnt stick a penny between them. It is mounted as instructed and there is no more room move the engine assembly up. I dont need to notch the blocks because that would certainly weaken them.

Third is the muffler on the Saito looks like its going to require that I cut the cowling because it extends to far out. Again no room for moving the engine assembly because it would throw the shaft off center. I'm hoping they make a slightly bent threaded tube to replace the one in there. that would give me the clearance..

Thats it for now.

rc.hackmaster

Feb 15, 2004, 06:37 PM

first, shorten the steering arm a little and you will have to open the cowl a little, but i would reccomend retracts they look soooo cool. 2nd lightly carve away the gear blocks to get clearance, they are nice and hard wood. i have had a couple of hard landings and even when i crashed the wood is still together. 3rd, you have the newer style of muffler. try to get the older style, i think it comes with the 100 but not sure. check horizon for the other style and i will try to get a pic of my cowl, granted its ugly after the crash but it will give you an idea of what it should look like. btw i used a saito 65. little shorter and skinnier of a motor. the 72 is the large engine block the 65 is the medium size block. but youll have good performance with the 72 use a 13x7 or 8 apc prop. another thing is you will have to add a bunch of weight to the tail, the tail cone is perfect for this. i added about 1.5 ounces to my tail you might have to add 2 oz. just a guess but good luck and let me know how it balances out. good luck, hack.:D :D :D.

The_Widowmaker

Feb 17, 2004, 02:18 PM

Well I'm finally done. As I said before, overall its a great ARF Kit. Only missing parts were the blindnuts for mounting the engine mount. Manual stated 6/32 blindnuts. Luckily I took one of the bolts with me to Home Depot. I tested it on a 6/32 and it was to small. The size is actually 8/32.

I thought about getting an angled nipple to bring the exhaust pipe inside the cowling but even doing that I would have had to cut away cowling anyway because the exhause port on the head was not completely inside the cowling so I left it as it was and just cut away for the pipe as well. My steering arm problem was solved by shortening the arm as suggested by hack. I also installed a quick fuel port. Retracts will go in this weekend but its ready to fly as is after I set the CG.

As far as breaking in the Saito. Book says not to exceed 4,000 rpm. I have not way to guage this so whats the best way to ensure I do not exceed that? Also on the Saito 72, right under the crank there is a nipple. Is this just for drainage? I ran a piece of fuel tubing from there and out of the bottom of the cowling.

rc.hackmaster

Feb 17, 2004, 08:10 PM

good job on the cowling! looks good. now all you need is the hangar 9 1/7 scale ww2 pilot. he fits perfect and looks really good in the cocpit. the nipple is for excess crank pressure and drainage. what you did with the fuel tubing is correct. as for breaking in the saito just dont throttle it hard and let run a bit above idle just dont go too far above idle run a tank or 3 to get it broke in. and keep it rich,rich,rich! good job it looks good. you will love flying it. remember set it down easy with the factory gear. the tires are hard as rocks (get some robart wheels they look better and have some cusioning effect)it will bounce and you could break loose the landing gear blocks in the wings. if you hear a pop on a hard landing you have. also flare at the last second on landing it kinda likes to just keep flying if you flare early. good luck! hack.

The_Widowmaker

Feb 17, 2004, 09:44 PM

Originally posted by rc.hackmaster
good job on the cowling! looks good. now all you need is the hangar 9 1/7 scale ww2 pilot. he fits perfect and looks really good in the cocpit. the nipple is for excess crank pressure and drainage. what you did with the fuel tubing is correct. as for breaking in the saito just dont throttle it hard and let run a bit above idle just dont go too far above idle run a tank or 3 to get it broke in. and keep it rich,rich,rich! good job it looks good. you will love flying it. remember set it down easy with the factory gear. the tires are hard as rocks (get some robart wheels they look better and have some cusioning effect)it will bounce and you could break loose the landing gear blocks in the wings. if you hear a pop on a hard landing you have. also flare at the last second on landing it kinda likes to just keep flying if you flare early. good luck! hack.

Thanks Hack. I have already hit a snag and I'm not quite sure what to do. I got a 2 1/4 inch spinner but the flange on the Saito 72 is larger than the area it should mate up to in the spinner backplate. Am I going to have to go with a larger diameter spinner to get it to mate up properly? Thats going to take away from the look of the plane if the spinner is larger than front of the cowling. Hope you have some advise for me on this one. Its not going work using the spinner I have.

Also on setting the CG... when I'm setting it to the recommended point, do I have the tank empty or full?

rc.hackmaster

Feb 18, 2004, 04:27 PM

first, cg always empty tank. if you do it full as you get to empty your cg moves back and the plane gets more and more unstable. allways do the cg with an empty tank. with a full tank its going to be nose heavy and thats ok. show me a pic of the spinner backplate ant the flange on the saito. ...are you talking about the 2 knurled surfaces where the drive flange and the spinner mate together at? i will be here later tonight. its 2:30 in seattle. i will be on after 9pm. hack.

The_Widowmaker

Feb 18, 2004, 08:39 PM

Originally posted by rc.hackmaster
first, cg always empty tank. if you do it full as you get to empty your cg moves back and the plane gets more and more unstable. allways do the cg with an empty tank. with a full tank its going to be nose heavy and thats ok. show me a pic of the spinner backplate ant the flange on the saito. ...are you talking about the 2 knurled surfaces where the drive flange and the spinner mate together at? i will be here later tonight. its 2:30 in seattle. i will be on after 9pm. hack.

I got the CG set late this afternoon so I didn't get to take it up. Spent most of the day driving because the nearest hobby store is about 100 miles round trip. I was able to get by with 1/4 ounce weight in the tail. I moved my battery pack behind the servo box and its secured nicely. That kept me from adding even more weight.

Yes the knurled surface (couldn't think of that before) is what Im talking about. Thats the reason I drove to the hobby store. I found one that works. The backplate for the first one is knurled and there is a raised ring around the knurled area. That ring was the problem because the flange on the Saito was larger. I found one that does not have the raised ring and was able to stay at 2 1/4 inch.

So now its just a matter of taking that first flight. I plan on tomorrow if its not to windy. I also picked up a tachometer so I can set the engine correctly. Off the top of your head, how far off is the break in setting of 2 1/2 turns, from being the optimal setting.... 1/2 turn, 1/4 turn ??? Just an approximate.

Again thanks for all of your help.

rc.hackmaster

Feb 18, 2004, 11:21 PM

approxamately 2 turns or so. since you have a tach user that for your final needle setting. set the max rpms for about 9500 to 10000 rpms. no more than 10 grand. it will do about 12 grand but play the safe side since its new. i set mine for 9500 with a 13x8 prop great pull. if you can weigh your plane. it should fall around the 6 1/2 to 7 lb mark. the 72 should pull stumps! in a 7 pounder it should fly really nice. btw on first take off ease into the throttle and get it rolling good then stab the throttle, wait for a little speed then just pull back and it will climb nice. also keep the elevator on low rate and the ailerons on high. the elevator on high rate will make the mentor snaproll if you give too much elevator in a tight loop. it does fly well on low rate. set high rate just a little more than low rate. although i never flew it on high rate after the first snaps. scares the s**t out of you! yikes! try to fly it scale with combined rudder and aileron it looks killer and very scale. stalls are fair and i dont remember if it tips a wing or not. but get lots of altitude and then try it. and dont slow down too much till you are ready to touch down, it does land kinda fast but not too bad. do you have a grass or paved runway? we have a canvas over dirt with grass on each side. 200' long or short should i say. the guys at our feild say (and so do i) if you can land at our feild you can fly anywhere. our feild is called nimitz feild. i call it an aircraft carrier cause its so short but i love flying there. hope all the info i have given you helps. where are you flying at (state)? good luck on the maiden flight! happy landings...hack

The_Widowmaker

Feb 19, 2004, 08:07 AM

Originally posted by rc.hackmaster
If you can weigh your plane. it should fall around the 6 1/2 to 7 lb mark. the 72 should pull stumps! in a 7 pounder it should fly really nice. Where are you flying at (state)? good luck on the maiden flight! happy landings...hack

Im in Vicksburg Mississippi. Im driving about 10 minutes to Edwards where there is a long grass strip used by crop dusters. Its at least 1/4 mile long. The only way I could weigh it was to weigh myself on a scale then hold the plane. Difference was 7 pounds.

Your information has been a great help. Thanks.

The_Widowmaker

Feb 19, 2004, 11:10 AM

All time getting ready and I was going to fly today. Broke in the engine as specified by the instructions. Started it up today from 2 1/2 turns open. Positioned the tach and started to turn in. The engine reached 8100(ish) rpm and would not exceed that. I went in a bit more slowly and it would then sputter and die, apparently starving for fuel. I called hobbytown and I am waiting on a call from them. I don't know what they are going to want to do but I certainly hope this does not turn into me waiting for the engine to come back from the manufacturer.

rc.hackmaster

Feb 19, 2004, 09:56 PM

what prop are you using? if it has a lot of pitch you wont get alot of r's. mine on a 13x8 gets just over 9 grand. more pitch=less rpm's and more speed. try using a 13x6 and read the tuning section in the manual. you should get a nice smoke trail with a blue sky background . btw my engine is only a 65. try setting it for the 8000 mark and try flying. it should fly fine. the 72 is a torker you dont really need alot of rpm's. our feild manager told me once that alot of guys try to squeeze as much as they can out of a 4 stroke thinking in 2 stroke. it just doesnt work like that. its all about torque. thats why i like 4stroke power big prop and low rpms. as long as you have the idle mixture set properly you shouln't dead stick. just in case you do the mentor does glide pretty well. and be easy on the new engine for at least a gallon of fuel. what fuel? i hope you use at least 15%. if you want alot of power try using 30% heli fuel, it'll run killer and have gobs of power. but dont try till you go thru a gallon first or regular fuel. more nitro will kill it quicker. let me know what happens. hack.

The_Widowmaker

Feb 19, 2004, 10:35 PM

Originally posted by rc.hackmaster
what prop are you using? if it has a lot of pitch you wont get alot of r's. mine on a 13x8 gets just over 9 grand. more pitch=less rpm's and more speed. try using a 13x6 and read the tuning section in the manual. you should get a nice smoke trail with a blue sky background . btw my engine is only a 65. try setting it for the 8000 mark and try flying. it should fly fine. the 72 is a torker you dont really need alot of rpm's. our feild manager told me once that alot of guys try to squeeze as much as they can out of a 4 stroke thinking in 2 stroke. it just doesnt work like that. its all about torque. thats why i like 4stroke power big prop and low rpms. as long as you have the idle mixture set properly you shouln't dead stick. just in case you do the mentor does glide pretty well. and be easy on the new engine for at least a gallon of fuel. what fuel? i hope you use at least 15%. if you want alot of power try using 30% heli fuel, it'll run killer and have gobs of power. but dont try till you go thru a gallon first or regular fuel. more nitro will kill it quicker. let me know what happens. hack.

I'm using a 13x8 prop. I wish the book was more specific about setting the rpm or gave some forumula to figure out rpm for what prop you are using. I was looking for around 9,500 to 10,000 so when I could only hit 8500 I was a bit concerned. I dont use need for tach if I dont know what max rpm to expect in the first place.

When you say 2 turns, are you saying that from 2 1/2 I should be able to turn in approximately 2 turns? I hope thats not the case because from what I could tell the engine stops showing any improvement on rpm after I turn in about 1/2 turn, which would be equal to two turns open.

I think I made a mistake getting the four stroke. 2 strokes are so much easier to set by ear and like I said, what use is the tach if I dont have a base rpm to start from for the prop I'm using? Im taking it back to hobby town tomorrow so they can check it out. Besides the 8000 rpm issue, I found that after setting the needle to where I thought was optimal from listening, the engine does not maintain a steady tone. You can hear the tone raise and lower in short subtle surges. Now I have to wonder if the engine has been damaged because I was going by the books instructions and trying to reach a higher rpm.

rc.hackmaster

Feb 24, 2004, 07:02 PM

dont give up on the 4 stroke yet. i talked to a couple of guys at the club who are 4 strokers. set for about 8500 to 9000 rpms on the ground it will go to the max rpm in flight, on the ground you are getting static thrust, in flight there isnt much resistance from the air. so the engine doesnt work as hard, and it will achive the max rpm for the needle setting. but dont set too lean or youll detonate the engine and that will do nothing good to the engine. allways set rich. ok i just read the saito manual and they have the peak rpms wrong for static tuning. open top mixture screw 2 1/2 turns and start. warm up and then check max rpms, try to set it for 8500 to 9000 rpms. you may need to open (richen)the top end a little or you may need to close (lean) the top end to achive proper rpm range. if you hear some loud popping or banging at max rpms in flight such as in a dive on a fly by, then your a little lean on the top end. it should sound clean and be pretty quiet. sorry if i didnt answer your question the first time. your engine should be ok , just try retuning and set for the rpm range i gave you and it should run great. be patient and give the engine a chance. i also have 2 strokes, they are good for sport planes but you cant beat the 4 stroke sound in a scale plane, its just an awesome thing to see and hear. if you want to try to call me for better explanation pm me. the hack....

The_Widowmaker

Feb 24, 2004, 09:11 PM

You information is always helpful and welcome. I took the engine back to hobbytown and the owner took it to an older experienced club member that is known for his knowledge of 4 strokes. He got it running correctly and said the valves were not correct from the factory. They say its running very smooth. Im going to pick it up in the next couple of days. Weather is bad so there is no real hurry. Of course I got a new spinner. Went from black plastic to aluminum. Had to get an adapter to make it work so its going to add more weight to the front so that means more weight to the back to balance it out. After a few flights and I am comfortable with it, Im going to get the retracts.

Paul Wilson

Feb 24, 2004, 10:25 PM

Hi Widowmaker,
perhaps I should have jumped in a little earlier, I didn't see the way the thread had gone until today.
Even if I knew the kind of fuel you were using and content plus the prop size and where you were running the engine and how you mounted it and what tank you had and where the tank was and what type of tubing and etc. etc. then it would still be difficult to tell you what rpms to expect. I am not trying to be funny just to point out the many things that peak rpm depends on, the manufacturers cannot give an exact number withoput taking the chance of having people burn their engine out or being so conservative as to make some combinations unusable. I will go out on a limb and say with a 13x8 on 15% fuel you can expect about a 9400 peak from others (not mine)experiences, you would back off about 300 and run at 9100 if that is right. Having said that. I did my buddies and I think we had it about there (8900-9200) with 15% wildcat here in Florida.
To be honest I wouldn't think of trying to set a four stroke by ear without a lot of experience, I don't, definitely not for top performance and longevity. The tach is the only way to go. The difference in sound between a few hundred rpms is less easy to hear with the 4c.
The thing is that you tune a 4c the same as a 2c. Warm up the engine set rich, open throttle wide and close the needle gradually letting the engine settle between turns until you find the peak rpm, then back off a couple of hundred rpm. Then you set the bottom end. The only difference with the 4c is that you use the tach to determine peak rpm's and not your ear ( it doesn't hurt to use the tach with a 2c either as it is more accurate).
I will say this, the first 4c I had was a saito 56, it was new to me and I had help tuning it from many experienced flyers. It was very inconsistent and unreliable. I found that I had let so many people mess with it that really had just a little more knowlege than I did and that was foolish. I called Saito and asked how to get the needles back to the factory settings and followed the instructions using a tach. Everything went great, it still had a few problems so I took the cowl off and noticed some bubbles coming in with the fuel, I balanced the prop as someone told me it could be vibration but no luck. Then I did some research and checked the length of the clunk in my tank, it was not touching the back but was close, maybe 1/4 inch, I took another 1/2 inch off and my bubble problems ended. Did a final tune by the book and the engine ran like a top all the way to 4 inches underground some time later when my ego overtook my flying skills. Since that time I have only bought one 2c, all my glow planes have 4c engines, (ys or Saito) and I couldn't be happier.
If you cannot get a fairly constant rpm after balancing your prop then check your fuel feed, tank position and muffler pressure.
Look for bubbles in your fuel line etc. Check your valves as if you have run it a little fast and you have a little fuel through it it will be ready for its first adjustment.
If you like I will post a complete run down of tuning the Saito including the bottom end, use the tach is the best advice I can give, the fuel economy,sound and flying character for a warbird I am sure will make you a 4c convert.
good luck
Paul
whoops, typed this while you weere posting the last one, glad you are sorted out.

The_Widowmaker

Mar 22, 2004, 09:54 PM

Believe it or not I took the mentor up for the first time yesterday and two more times today. I was waiting on my AMA and joined the local club. I give this ARF two thumbs up on flight. Its stable and looks very good in flight. The retracts really touch it off. The Saito seems to be running ok. In the process of waiting on my AMA I got the H9 Funtana S40 ARF and another Saito 72 and a flight pack. I took it up yesterday and today as well. Roll rate from hell even with the aileron throw 1" less than suggested. This ARF was alot easier to get ready since the wing is in one piece. The covering was perfect. Its also very stable and floats in for landings. The mentor does very well at low speeds but weighing almost twice as much it does not come in as slow.

Thanks for everyones help and input.

Lots of plane pics at http://www.pbase.com/rz22g

Ice

Mar 26, 2004, 03:28 PM

I have one and getting ready to maiden her out this weekend.. cg is from root AGAINST fuselage not typical leading edge.. please confirm...
Nickel

The_Widowmaker

Mar 26, 2004, 10:01 PM

Originally posted by Ice
I have one and getting ready to maiden her out this weekend.. cg is from root AGAINST fuselage not typical leading edge.. please confirm...
Nickel

I attached the wing and measured from the leading edge of the wing right against both side of the fuselage. Thats the way I took the instructions to mean. Either way it worked out great. Very stable even at low speed. Its a joy to land.

Ice

Mar 29, 2004, 10:49 AM

thats what I did, thank you sir

denday76

Aug 11, 2004, 03:21 PM

Can I put a 4 stroke 90 on a t-34 mentor? the largest it calls for is a .72.
hangar 9 .40-.46 size arf.

Ice

Aug 11, 2004, 03:49 PM

It will be hard to fit in the cowling my 72 does and it has enough guts..otherwise sure

NOSInjected00GT

Jun 06, 2005, 12:49 PM

how does this airplane fly? is it more aerobatic than a basic trainer?

Ice

Jun 06, 2005, 01:32 PM

if you consider aerobatic as is real airplanes. Yes very much so... I dont consider 3d or 4d flying airplanes... maybe cause I am a pilot.

I highly recommend her as great fun for any occasion.

av8r4aa

Jun 10, 2005, 10:34 PM

I have the Hangar 9 T-34 arf.
I did a few mods but not much.
I drilled out the retracts and installed a larger wire. (mains only)

I had a old set of wheel well liners painted them and glued them in.
While doing gear I made a set of outer gear doors, just some scrap plastic.
.
As for the wing I do not like those servos hanging out in the breeze.
I purchased some servo covers from Hobby Lobby made them flush and painted those also, much cleaner look on the underside.
For the noise maker I had a trusty OS 46 SF engine plopped it in and a Graupner 11X6 2 blade prop. perfect fit and power.

I did not like the plastic wing walk and the glare shield so I removed it and painted it flat black
Decals looked too skinney to me changed them out for a set I had for another plane.
The rest of the plane was mostly box stock as per the instructions.

As for flying it does it all fast slow and everything else in between.
You do need to get the plane slowed up to land wants to come in fast.
I slow it down early and get that slightly nose high look for landing.
I would build another one if I needed to.
I haveoinly flown it on a paved surface, grass is unknown
Two thumbs up here

Wren

Jun 21, 2005, 09:27 PM

For fuelproofing, I like to use Aerogloss / Dope. It's meant more for silk covering etc, but as long as you get the fuel-proof kind it works pretty good on all the woods you would normally use thinned epoxy on. Plus you can get your innards to match your plane's exterior. Or for the T-34, I used gray on the wheel wells and all visible wood near the firewall. Makes it look like real internal metal!

My issue though is the fuel tank on the Hangar 9 Mentor. It barely fits, and even with thin foam, it's so tight in there I have to think that it's going to vibrate right through the compressed foam and foam up the fuel. What have others done about this? The only way it goes in is if I make sure the fuel cap goes into the large center hole in the firewall. Then the back just clears the instrument panel's wall. So there's really not a lot of options for giving it more room short of buying a different tank. Eeek. I can make the firewall hole bigger and maybe sand the panel at the back of the tank but that's about it. Otherwise, I'll just run a few tanks of fuel through it and see if I can spot any fuel problems. I really want to fly this bird this weekend!

Ice

Jun 22, 2005, 10:40 AM

I put vib supression on the motor mount.. not an issue now

db4962

Jul 14, 2005, 02:16 PM

Any updates on the T-34? I was considering getting the ARF version. Also didn't know if one brand of .46 size engine would be better for this bird than another. I would like to get a 4-stroke, but that is a little cost-prohibitive right now.

RDD

Oct 23, 2005, 06:49 PM

Hi Guys,

Can anybody tell me which color of Ultracote the Yellow is on this plane (Hangar 9, t-34 ARF version)? I have to do a little "patching" on mine (due to an unplanned corn field incident), and their website (horizon hobby) lists 3 different shades of yellow. I have to mail order it, since my locality is hobby shop challenged, and I can't seem to tell which color shade it is. I apologize if this has been addressed, but my searching has led me nowhere, and I'm sure some of you guys will know. Thanks in advance for any help.

Ron

Ice

Oct 24, 2005, 11:13 AM

Its in the manual in the back

RDD

Oct 24, 2005, 11:33 AM

I don't have the original manual. But, I downloaded it from the website and I just didn't see it in there. Am I just missing it?

Ron

Ice

Oct 24, 2005, 12:21 PM

Wing Span: 57.25 in (1454 mm)
Overall Length: 45 in (1146 mm)
Wing Area: 555 sq in (35.8 dm²)
Flying Weight: 6 - 7 lb (2.7 - 3.2 kg)
Engine Size: .40 - .46 2-stroke, .56 - .82 4-stroke
Radio: 4 channels
Servos: 5 (6 w/ retracts)
Trim Scheme Colors: HANU884 Cub Yellow, HANU874 Black

RDD

Oct 24, 2005, 02:50 PM

Thaaank You!!

gosmondson

Apr 09, 2007, 02:51 PM

Just got a newer (white/red) T-34 from H9. So far I love everything about the plane.. The H9 retract install was very easy (a little sanding, line things up and call it good). I am still waiting on getting a powerplant for this guy, I was thinking of going with the SAITO .82GK. Anyone have any experience with this setup?

rz22g

Apr 09, 2007, 04:34 PM

gosmondson

Apr 10, 2007, 11:38 AM

This plane to me had the most realistic flight feeling of any plane I have owned. My only complaint would be with the front retract if you are landing on a grass field. Eventually my front gear would twist when landing and the wire would bend slightly. I could straighten but it would do it again, getting worse each time.

I was thinking about trying a 2 1/2" wheel up front to help for this, as my primary field is grass. It fits but barely and it would be very easy to bind up..

What about using like a robostrut or something? There are a few posts showing people having a strut up front to help with shock, and it gives a nice scale look too...

Dora Nine

Apr 14, 2007, 07:59 AM

I've had good luck with the kit supplied struts. PLenty of take-off's and landings with them. The only change I made was the main struts. I removed them from the units and then use my dremel to cut a notch to match the one supplied. I then use a fair amount of RED lock-tite to hold the strut and set screws in place. Since then, I haven't looked back. Mine is powered by a Magnum 46 with an 11X7 prop. It's quiet and damn fast.

Sir Barf

Apr 03, 2008, 08:33 AM

Hi
Just bought the new version (white/red). Im not sure if I´m going for an electric or an fuel engine on this bird. I have an OS 70 II that might fit but what about electric engines in this one ?? Has anyone tried electrify this bird, what kind of electric set up is used ??
Is the OS 70 too heavy (do I have to add lead at the tail) ?? What fuel engine is the most suitable (no lead attach to the nose or tail) ?

Does the new version have the same high speed landing as the old (yellow) one ?

Are

Dora Nine

Apr 04, 2008, 04:15 AM

Instead of adding lead, think of using a bigger battery, why carry dead weight when you could carry extra power for servos, etc.

tmulder

Apr 05, 2008, 03:09 AM

I built the new red and white one and love the way it flys. I have a Saito .82 with a MAS 3 blade 12X8 with a TruTurn spinner. I started with a 13X8 2 blade but with the 3 blade it looks more scale and the .82 satio works really well with this prop on PowerMaster YS 20/20 fuel at about 9500 RPM.

I enclosed the front wheel well to keep out the goo and used 1/32 ply to build a A frame type enclosure. I also made the Flap modification detailed at the following RCU link: http://www.rcuniverse.com/forum/m_1893157/anchors_1893157/mpage_1/key_t%252D34+flaps/anchor/tm.htm#1893157.

The plane came it at 6 lbs 14 oz and I had to add 7oz of weight in the tail cone to balance. I used the stock retracts and they work fine a pavement.

This is a really fun plane to fly and always gathers attention at teh field.

Dora Nine

Apr 07, 2008, 01:56 AM

tmulder: Any pics?

tmulder

Apr 14, 2008, 11:18 PM

Here are a few pitures of my T-34 with the flap modification

Mchone, Jake

Apr 22, 2008, 10:17 AM

How did you do your flaps!?

I wnat flaps on mine and cant believe it came w/o the option, but a retract option!

Also, why the color scheme change? I like the yellow better :(

tmulder

May 20, 2008, 03:45 AM

Jake,

Here is the info on the flaps. They were pretty easy to do.
http://www.rcuniverse.com/forum/m_1893157/anchors_1893157/mpage_1/key_t%252D34+flaps/anchor/tm.htm#1893157

Tom

stallwart

Aug 10, 2008, 09:41 PM

Here's my just completed older version of the H-9 Mentor. Maidened Saturday and what a surprise----no trim adjustment needed!---even the engine mixture stayed the same as when I broke it in on the test stand back in April!

Dora Nine

Aug 11, 2008, 07:04 AM

Nice job! The cowl looks really good. Glad you like it, just keep up the speed on landing, she'll stall and go into a spin.

stallwart

Aug 11, 2008, 09:19 PM

Thanks D9. Yes, I read many threads about this plane that advised landing with a bit of speed and power. Actually, this rascal floated in nicely just a few clicks above idle, even in a crosswind. Heck, I haven't even bounced it on landing yet---a mainstay with my flying.

The main thing is it tracks better than any of the 20 or 25 planes I've owned or flown and although not a true aerobat, it does pretty much everything except hover----well, I can't hover anything anyway.

If the newer version, according to Horizon Hobby, has improved flight characteristics, I might have to have one of those too, although I sure like the "school bus" trainer scheme more.