600 UH-1N Twin Huey- ARF Bundle - Build and Impressions

[F106DeltaDart]

Looking forward to seeing it assembled - looking very good so far. I thought that you had set yourself a bit of a harsh target for completion - been there and got the tee-shirt. I once worked day and night for a week to get an ME109 finished for a club airshow and likewise, only had it out for non-flying display on the day. Promised myself that I would do my best never to repeat the exercise(much to the family's relief) ;)

Thanks Cyclone, it’s definitely been a rush to try to get it out (even for static) this weekend. I honestly think I’m maybe 50% through the build. I threw together the mechanics today, and will definitely need to completely redo them later. Also found a few issues with the servo linkage geometry that will require some rework. Anyways, after about 8 hrs of work today, here’s where it stands for static display:

[icepirate3]

Looks great! I really like the black on the rotor assy. I may do that myself. Looking forward to your write-up on the mechanics as mine are still in the box. If you don't mind, please post any tips you may have on the raised tail as there are some spacers in there that I have no clue where to put. I sure wish Roban would start including some sort of instructions on assembling and setting up their 600 mechanics.

[F106DeltaDart]

So, I brought the UH-1N and the rest of the scale heli fleet out to the TX Scale Championships today, and it was great! Excellent weather, great people, and some incredible aircraft! Now just to get this machine finished!

Looks great! I really like the black on the rotor assy. I may do that myself. Looking forward to your write-up on the mechanics as mine are still in the box. If you don't mind, please post any tips you may have on the raised tail as there are some spacers in there that I have no clue where to put. I sure wish Roban would start including some sort of instructions on assembling and setting up their 600 mechanics.

Will do Icepirate! I will post photos and a detailed write-up of the assembly of the mechanics. Waiting on a few parts to come in from Motion to continue work on the mechanics.

[Alpha]

Hi DeltaDart, I look forward to see your write-up of the mechanics and assembly. Your photos look good!

[F106DeltaDart]

Hi DeltaDart, I look forward to see your write-up of the mechanics and assembly. Your photos look good!

Thanks Alpha! Things have been pretty busy, so I am just getting to the mechanics again. First up was installing and shimming the metal gears for the torque tube. The kit includes some nicely machined metal gears to replace all of the bevel gears in the Chaos 600. For the tail pickup, I did change the gear arrangement up a bit. If you are sticking with stock (CW) rotor rotation, the following will not need to be changed, and can be ignored. However, I wanted CCW scale rotation on the main rotor. So, I pressed out the one-way bearing with an arbor press, and pressed it back in upside-down. However this also reverses your tail rotor direction. For highest efficiency (and scale) the innermost tail rotor blade should always rotate up, into the rotor wash. To make this happen I had to move the tail bevel gear from its stock position (above tail output bevel gear) to below the bevel gear. This was easily done by extending the flat spot on the shaft using a dremel cutting wheel.

The gear positions were then adjusted using the included shims. Gear mesh should be tight, with just a bit of backlash between the 2 bevel gears. The gears were the lubricated with synthetic grease. All metal to metal joints will require lubrication to reduce wear. Another item of note to those building this kit, is that sets of specs are included. The Chaos mechanics are wider than the Trex 600 ESP it was designed for, but the spacers allow them to be stretched to the larger size. These are the blocks shown on the inboard side of the tail shaft bearing blocks in my photos. Also of note, is that the builder will need to secure the bearings inside the tail bearing blocks with a retaining compound. Otherwise they are just floating in the blocks, and can easily be knocked out.

Finally, for the main shaft, the kit includes 2 sets of bearing blocks, but the frames have provisions for a third below the main shaft. Even though the stock 2 should be more than adequate for scale flying, I elected to add a third using Trex 600 spare parts: http://www.aligntrexstore.com/Bearin...1-_p_1556.html. More to come soon.

[echopoint]

How much does this guy weigh without batteries? Just curious! Looking great. Keep up the good work.

[F106DeltaDart]

How much does this guy weigh without batteries? Just curious! Looking great. Keep up the good work.

Echo, I'll throw what I have on the scale tonight. At this point, its hard to judge since the mechanics aren't completely finished, and I haven't tried to balance the airframe yet.

[echopoint]

Thank you. It doesn't need to be an exact figure. Just trying to figure out a ballpark weight.
Best wishes!

[F106DeltaDart]

Thank you. It doesn't need to be an exact figure. Just trying to figure out a ballpark weight.
Best wishes!

Sorry, didn't have a chance to grab it last night. Will try to get it tonight for you.

[F106DeltaDart]

Thank you. It doesn't need to be an exact figure. Just trying to figure out a ballpark weight.
Best wishes!

Right now, it’s weighing in at about 9.5 lbs. Thats all the airframe and electronics. I will likely still have to add a significant amount of nose ballast though, if my other Hueys have been any indication.

[echopoint]

Wow. That's actually lighter than I expected. I am assuming that is without batteries. Keep up the great work, and thanks for the info!

[F106DeltaDart]

Wow. That's actually lighter than I expected. I am assuming that is without batteries. Keep up the great work, and thanks for the info!

Yes, that is without battery. I'd assume another pound or so will be pretty close to the finished empty weight for the aircraft.

[F106DeltaDart]

Have been messing around with some 3D printed pilots for the Huey. Found the model on thingiverse, rescaled it, and it’s a perfect fit! Planning on printing another soon.

[icepirate3]

I have been thinking about printing that one as well. Did you have to enlarge or shrink him and how much? Thanks!

[F106DeltaDart]

I have been thinking about printing that one as well. Did you have to enlarge or shrink him and how much? Thanks!

Yes, I scaled him down to about 65% of his original size.

[icepirate3]

Thanks! I will get it printing on my next night off. Should be fun to paint.

[F106DeltaDart]

Just finished painting up my pilots today. Also added some decals for the unit patches and flags for some extra detail. Painting faces has never been my specialty, but I think them came out at least looking human this time LOL.

[F106DeltaDart]

A few more quick notes getting back to the mechanics. The stock bearing blocks for the lowered tail driveshaft have the bearings free floating, and they can easily pop out if not secured properly. Some loctite 641 was used to secure these to the blocks. I also noticed a slight geometry issue with the aileron bellcranks from the Chaos 600. The Chaos horns are offset from 90 deg. This offset works perfect for the Chaos frames, but Roban frames for the Huey are designed for 90 deg bellcranks. I ended up using some Trex 600 spare bellcranks to achieve correct linkage geometry.

[icepirate3]

Good to know!

[F106DeltaDart]

Finally got back into finishing up the mechanics this week. Just a few servo wires to secure and the tail will be all that’s left! I am using a brain2 FBL along with a Spektrum AR9030T and 3 sat rxs. One note is that I ended up spraying the top on the motor black using some high heat paint for grills. It is very visible from the top in the stock gold color and looks much more subtle when painted.

Also, while doing some research on the 36th RQS, I found out that they do training flights to get military dogs used to working in and around helicopters. Naturally, I couldn’t resist 3D printing a new member of the flight crew. Planning on putting a dog handler, pararescue specialist, and a crew chief in the back along with Rex. Stay tuned!