Hobby King 1875mm B-17G Flying Fortress V2

[jetfool]

Dave you might make a 3d gear leg to get it scaled then have a local machinist turn the leg for oleo action from alum.. If you provide the drawing he should be able to turn the parts quickly and at a reasonable price. Add 3d parts like we did on our Corsairs

[F106DeltaDart]

Thanks, 106DD. I've repossted some and hopefully they will show ok now. Very weird.

While I have your attention, I haven't given up on finding some Flightline B-17 main landing gear, but I have to brace myself that that will not happen. Instead, although I HATE to use the round springy gear, I might have to do something along those lines.

I could just leave everything stock on this, and live with the fact that the airplane's stance is way too high. Another idea I have is possibly modifying the landing gear steel strut by opening up the servo and cutting about 1/4 inch off the strut so that I can lower it in the retract a bit. I'd rather get rid of the strut completely, but that might not be possible. I would still have the functioinal circular spring, but it would be closer to the retract and make the model's stance a bit lower.

I looked online for HK and wanted to order a replacement main gear retract where I could test this theory out, without endangering working gear that are installed. I mean, if they don't sell retracts, I can't take the chance of screwing up the ones that work if I can't get replacements. Maybe I missed the part on their online parts finder where you can order replacement gear for this airplane.

Do you have any thoughts on this, or some other way I can go with a different strut from a different model that I could put in this retract as a more scale replacement?

Thanks for any thoughts on this.

Cheers

Davegee

Dave, mods are looking good!

For the landing gear, I still think your best bet is to buy those FMS FW-190 74 deg retracts that I linked earlier and try those with the stock struts to get the stance right. It should significantly lower the stance, assuming everything will fit. The Freewing B-17 retracts would still be most scale option, but its a shot in the dark to find them.

As for struts, that's going to trial and error. You'll still need that bend from the retract, but maybe you could retrofit on a strut on the end after the coil spring. You would need a really short strut though. Maybe the mains from the eflite 64mm A-10 or the new Xfly F-22 main struts. Those are the shortest ones I can think of.

[davegee]

Dave, mods are looking good!

For the landing gear, I still think your best bet is to buy those FMS FW-190 74 deg retracts that I linked earlier and try those with the stock struts to get the stance right. It should significantly lower the stance, assuming everything will fit. The Freewing B-17 retracts would still be most scale option, but its a shot in the dark to find them.

As for struts, that's going to trial and error. You'll still need that bend from the retract, but maybe you could retrofit on a strut on the end after the coil spring. You would need a really short strut though. Maybe the mains from the eflite 64mm A-10 or the new Xfly F-22 main struts. Those are the shortest ones I can think of.

Great info, F106DD! I'll wade through it and see what I come up with. Appreciate your inputs, as always!

Cheers

davegee

[davegee]

Davegee,
Pictures have arrived. The mods look fantastic, you and Dan are doing a great job. It's nice to have a local friend that enjoys the same things.

Best Regards, Rex

Thanks, Rex. Dan has a better knack for the 3D designing than I do. I'm hopeful we'll come up with a good printed Cheyenne turret that will fit on with the existing fuselage where we removed the stock tail piece. We'll see...

Cheers

davegee

[davegee]

I took the HK B-17 out for some taxi tests, range tests, and some full power checks to be sure everything was running ok. Everything worked out fine except for the runups using the stock propellers. The first static runup went fine running it near full power for about 15 seconds when one of the propeller blades on the #4 motor departed the airplane and damaged the thin plastic cowl behind it. I did some more static tests indoors after replacing that propeller with some static runups of about 10-15 seconds. This time, when I powered down to a stop, one of the blades made a grinding noise. I discovered that the cheap plastic hub of the prop can come apart even though the propeller stayed on the motor. But that would have been a problem had I been doing a flight on it.

So, it looks to me like there are a couple of things at play: First, the quality of these props seems to be "garbage" to me, and are not trustworthy to put this plane in the air. I'm very disappointed in Hobby King for the difficult to follow website in finding replacement parts when needed. For instance, should I have to replace a common main gear retract servo and/or steel strut for the same, I did not find anywhere where important parts like those could be found to buy online.

Second, I did buy several Master Airscrew 3-bladed 8x6 inch propellers that I could use in place of the stock props from HK. But I don't understand how to attach them to this airplane. They do have some plastic molded bearings that come with each prop, but I don't see how they would attach to these stock propeller shafts of the HK model.

Any ideas or comments would be much appreciated. Other than this problem, the rest of the airplane went together well, and taxiis well on the street and has good turning radius with the new retractable tail wheel that I installed.

Davegee

[jetfool]

Sometimes when modeling problems arise, walking into our woods and screaming at the top of my lungs helps, most times it gives me a sore throat.

Hang in there Dan, you're doing a great job

[f4u ausie]

Dave I have bought 1 and 1 only HobbyKing plane... The mig 17. Camo... To b fair once in the air it was a trooper.


But to get it their. I replaced the ESC and 4 servos.
Was alot work.. the gear was great..
Dought will ever buy another... Unfortunately 4 U a must airframe was required.b17
I'm sure you with your knowledge and skills will do it justice for your. passed father in law.. looking forward to C pics Infront of that. mountain..

[F106DeltaDart]

Dave, I had to check how my Master Airscrew props are mounted. I just used 2 nuts on either side (torqued against each other to prevent slipping) and some washers in addition to the stock adapters for the smallest diameter. Has worked fine for 10 years now.

[F106DeltaDart]

More prop mounting pics from the RCG thread: https://www.rcgroups.com/forums/show...&postcount=334

[davegee]

Dave, I had to check how my Master Airscrew props are mounted. I just used 2 nuts on either side (torqued against each other to prevent slipping) and some washers in addition to the stock adapters for the smallest diameter. Has worked fine for 10 years now.

Thanks so much, F106DD. I was thinking that I would need to go to the hardware store and get some nuts and washers to make it work. I'll look into that. I'll start working on balancing the MAS prop, rounding the tips as you have, and making sure they are BALANCED!

I have to admit that before this test runup with the stock props, I did not balance them before, and that could very possibly be the cause of my problems during runup. If so, that's on me. Going forward, I will balance every one of the props that go on this airplane. I'm guessing that in the test where one of the stock prop blades departed the airplane while doing a static runup must have Really been out of balance! But hopefully this will work out. The plane is pretty much ready to go, although I'm still a bit tail heavy and need to put a little weight in the nose to get it in the 85mm-110mm range, aft of the forward leading edge of the wing.

Cheers

davegee

[davegee]

Dave I have bought 1 and 1 only HobbyKing plane... The mig 17. Camo... To b fair once in the air it was a trooper.


But to get it their. I replaced the ESC and 4 servos.
Was alot work.. the gear was great..
Dought will ever buy another... Unfortunately 4 U a must airframe was required.b17
I'm sure you with your knowledge and skills will do it justice for your. passed father in law.. looking forward to C pics Infront of that. mountain..

Good point, Craig, and I agree with you. There is MASSIVE difference between folks like Motion RC, E Flite, and HobbyKing. If they still had the Flightline B-17, no queestion I would not even have considered the HK B-17. I don't see getting another HK product in my future. But I hope to get this plane flying ok someday,maybe even this winter on a calm day inbetween snowstorms! We'll see....

Davegee

[F106DeltaDart]

Its a shame that HK hasn't upped their parts and CS support. They've released some fantastic models. The new PBY and Avios Spitfire are very nicely done and great flyers.

[jetfool]

Motion RC is my go-to store for foam scale models, FMS 2nd. They provide good friendly service and have parts for most of their models from years ago.
Rex

[Evan D]

I've spend many thousands at HK over the distant past. I love the EFXracer/EFXtra and have bought at least 16 of them for us to pylon race here. My Mig 17 has been great. I did replace most of the hardware but otherwise it still operates great and fly's even better. That said I don't buy much from them anymore, most because they don't have things to buy.

Motion is also my go to. I don't use the word hate much, I highly dislike HH, more their attitude than anything else. If I buy from them it's usually through Amazon. Currently I have a couple Apprentices. a TimberX and a V1200. No one makes better than those specific planes so it had to be HH. Also I use a Spek TX, have for the last 7 or 8 and love them and their service. Their receivers are too expensive though.

[Aros]

Dave, I had to check how my Master Airscrew props are mounted. I just used 2 nuts on either side (torqued against each other to prevent slipping) and some washers in addition to the stock adapters for the smallest diameter. Has worked fine for 10 years now.

I was just coming on here to say that's how I did mine too and they worked great. Those stock props are laughable at best. I remember those! I think you could blow on them and they would move backward.

[davegee]

I was just coming on here to say that's how I did mine too and they worked great. Those stock props are laughable at best. I remember those! I think you could blow on them and they would move backward.

Thanks, Aros. I think I'll just remove the thought of those very flimsy, oversized props from HK, and finish up balancing and finishing rounding the tips to look more scale. They being much smaller than the stock props, they look stouter, too. I will probably ccontinue with static runups with the MAS props next week.

davegee

[davegee]

Thanks, Aros. I think I'll just remove the thought of those very flimsy, oversized props from HK, and finish up balancing and finishing rounding the tips to look more scale. They being much smaller than the stock props, they look stouter, too. I will probably ccontinue with static runups with the MAS props next week.

davegee

I am working on the MAS propellers. Did round the prop blades and now have them in paint for the tips and I also repainted the props matte black after sanding on them a bit and removing the MAS decals painted on each blade. I painted the blade tips white, and then will paint them yellow to get a better look.

Did a runup with one of the blades on the number 1 engine. Difference with the MAS versus HK was like night and day! They are very strong amd I ran it up to full power a few times momentarily indoors and they were solid as a rock. I will still balance them tomorrow just to be sure, but I think these MAS props, besides being much more scale and a ton stronger, should do the trick.

I'll attach a couple pics of the test engine (#1) without the cowling that was damaged in the runup the other day when the HK prop came apart during a test runup.

[davegee]

I got all the MAS blades painted, balanced, and installed on my plane today. They seem to run much better than the stock blades and I will stay with the MAS blades. They're also more scale so that is a good thing, too.

Will continue to learn the important parts of this airplane and do more taxi and runup tests when the winds are calmed down and the street is clear of snow or ice. There are some smaller details to do like pitot tubes and other things like that. Eventually, I'll take it out to the field for some taxi and runup checks, etc., and eventually try to get the maiden flight completed, whenever that works out.

The plane balances near the aft recommended CG position of 110mm behind the leading edge of the wing at the wing root. That shold work out ok, hopefully.

One thing I haven't done yet is figure out how to get this in my truck safely and drive out to the field! I think it will fit, barely, if I take the wing apart from the fuse and pack it in the truck somehow.. I'll figure something out.

Cheers

davegee

[Aros]

Nice work as usual davegee. I remember mine fondly. Lots of great sorties with her. Here's a maiden video from years ago on a snowy day. Thought you might enjoy.

[jetfool]

Yea PROGRESS. Looking good Dave. I am looking at trailers because I can't get enough planes for a day's flying in my truck. Club members have several 10-12' long trailers and they don't have to dissemble them. Might be an option for you
Best Regards,Rex