Official Dynam 1500mm B-26 Marauder Thread

[borntoolate]

Hey dude, do you put eleven hobby bearcat motors and 58a esc’s In your B26! You certainly have my attention now lol-what’s the Watts/amps figures like on the motors vs what the motors are rated as I notice the eleven hobby bearcat is a 3S plane? I only ask because I have been burnt following advice of others on RCG with this kind of mod and ended up melting my motor mount plate! Also, what’s this “Freewing retract mod” you speak of?? (My B26 is on order and due in the next few days so I’m all ears on decent and proven modifications). Thanks in advance!

I flew my Bearcats - 3 of them - all on 4S. Not to be a hot-rodder, I just have lots of 4S batteries. It has been awhile but I am sure I upgraded the ESC's in the Bearcats. I never had issues with the Bearcats. The motors were available and the motors/esc set-up in the stock B-26, in my opinion, is anemic. Had to fly at mostly full throttle during the flights.

As for the retract mods - I have almost always has trouble with Dynam retracts. I replaced the main retracts with Freewing MiG21 retracts. The nose gear retract was replaced with an FMS P-39 nose gear retract. The mains dropped right in, the nose required some modification. I also added oleos to the retracts.

The new motors give the plane the speed that it was lacking. And the retracts work every time!


Bob

[edwarda10pilot]

Hello everyone. I have just purchased the Dynam B26 and have a question regarding the location of the CG. The manual (if you can call it that) suggests that the CG is between 70 and 75mm aft of the leading edge of the wing at the root. Can some of you chime in on where you have located your CG and how the plane flies at that location? I am in the process of refinishing my plane in the colors and nose art for one of the planes my late uncle flew in World War II. As soon as Callie gets me the graphics, I will post some photos.

Thanks in advance for your input.

Ed

[Mad Baron]

I balanced my B26 at 70mm and it flies well for me.

[edwarda10pilot]

Mad Baron:

Thanks so much. I have mine balanced at 75 but will move it to 70.

Thanks,
Ed

[themudduck]

Mad Baron:

Thanks so much. I have mine balanced at 75 but will move it to 70.

Thanks,
Ed

There's been a long discussion on this thread about the balance point and a bunch of other things that need to be done - read through posts 20-30 (approx.). Of course you'll find lots of opinions here on the Squawk, but here are some tips and a short list of some of the things that you really need to check:
- If top hatch won't fit - move the magnets, the factory glued them in the wrong place (at least on the earlier planes)
- Check the mounts in the fuselage for the wing bolts - they can right pull out. Best to epoxy the mounts into the fuselage.
- Stock plane will need "up" elevator trim.... instead, raise the entire TE of the horizontal stab by 3mm using a shim - your plane will fly a lot better
- There are two weights in the tail (in the space where the tail guns go) - get rid of them
- Check the flap hinges, on many models they are loose (not glued on well)
- Use flaps for takeoff (1/2 position), landing (full position) every time
- Keep the control throw very low on the elevator. Too much elevator and this model will snap-roll in a heartbeat
- Keep the weight down. A 3600 battery works fine. Doing that along with removing the tail weights results in a lighter plane.

I replaced the racing-car tires on mine with skinnier foam wheels from Dubro, and I used a slightly large nose wheel to get the nose up (the real plane sat with the nose up).
I balanced mine between 55-60mm (measured from the LE of the wing where it meets the fuse, not the fillet. Flight testing shows that this is not nose-heavy. But there's been a lot of argument on that.

I made this video specifically to show off how nicely this model flies and how easy it is to make it snap-roll. This is with the forward balance point.
I didn't like the first landing very much, so I did a second flight on the video - second landing was a little bit better!

[Mad Baron]

It seems that each plane is different. Mine still has the tail weights and the 70mm cg works good for me. I also fly mine with a 3600.

[edwarda10pilot]

Thanks guys. I have done some of the things suggested above but will check the wing bolts. Mine did not have any weights in the tail section. I currently have mine balanced at 70 with a 4000 mah battery. I did end up regluing all of the flap hinges as they were either poorly glued or not at all. I replaced the nose and main wheels with some Robart "scale" treaded tires. I also refinished the plane and added some weathering. Will show photos shortly.
Thanks again,
Ed

[edwarda10pilot]

I just finished painting and weathering the Dynam B-26.The story behind this plane, Frances Joan, is that it was the plane one of my uncles (Luis) was flying when he was shot down and lost in a bombing mission over Ovierto, Italy in January 1944. He was on his 36th mission and had he completed one more he would have rotated home. My uncle (pilot/aircraft commander), his co pilot, navigator and bombardier were all lost in the crash. Only the tail gunner and the turret gunner managed to bail out. My dad, two of his older brothers (Luis and Al) and his younger brother William all served in World war II. Luis flew the b-26, Al flew the B-29. My dad and his younger brother were in pilot training in 1944 when the Army Air Corps decided they had enough pilots so my dad was transferred to the infantry where he served with Patton in Europe in 1944 and 45.

For the paint I used Tamiya Olive Drab for the top and sky/blue/gray for the bottom. For the weathering I wanted to simulate the paint peeling off of the plane and exposing the bare aluminum so I used a plumbers acid brush dipped in Tamiya aluminum and just stippled it all over the plane. Once the silver was on the plane I used a tissue to smudge the silver in a direction that looked "right". For the rest of the weathering I use artist pastel chalk. I used pink to simulate the av gas flowing back from the gas caps on the top of the wing and I used the gray, black and brown to simulate oil, grease and wear and tear on the plane. Once I had applied the pastel chalk I then used a tissue to spread the chalk in the direction of airflow for the grease and exhaust stains. I used the black to simulate the corrosion on the plane. I applied the black to the tops and bottom of the wings and tails and spread the chalk aft (in the direction of air flow) and for the fuse and vertical tail I spread the black vertically as it would have flowed down those surfaces while sitting in the elements while on the ground. Once all of this was done I sprayed the entire plane with Tamiya flat clear. I replaced the stock wheels and tires with similar size Robart scale wheels/tires.

Ed

[Mrdronenut]

Hey y'all!!! I just ordered my B-26 from Grayson Hobby. It will be here the 1st of the week. Thanks to all for you're input through out the thread.(HEY BOB!)LOL

[Mrdronenut]

Got it in. It was "as expected". Strange thing tho.......... I got a 5s,4500mah battery,and none of my Dynam planes......not one.......stock everything, would let me set the throttle. Flight surfaces,retracts,everything works. But the motor. It just beeps twice.
Ok all you airplane guru's,figure this out. I can put in a 3s,4s,2s,activates great. 5s.......beep beep..........beep beep........beep beep.

[xviper]

Those ESCs were only meant for 2s - 4s.

[Hardway]

Those ESCs were only meant for 2s - 4s.

Roger that!!! There is the problem...….. Glad they beeped and didn't smoke!!! ;):Cool:

[xviper]

Roger that!!! There is the problem...….. Glad they beeped and didn't smoke!!! ;):Cool:

For sure. I'm a bit surprised that Dynam ESCs would have such "smarts" built in. I've smoked better branded ESCs with just the accepted battery in them.

[Mrdronenut]

Thanks y'all. I worked on that plane for hours,called BTL and TIA. Then I put in a 4s. All good

[Builda]

OK so as everyone knows with every brand of Foamy every so often someone gets a “less than perfect” airframe. This week I had the pleasure of finding mine amongst my many boxed up planes awaiting build-unfortunately it was my B26 ????. It had a few minor things with the fuse where it needs more glue on stuff, but it also had a rather serious mismatch problem with one of the engine nacelle’s, due in part to a badly moulded (I believe) center wing section. I’ve spoken to a number of people on the internet with this plane and it seems I did indeed just get the one bad one???? So yesterday I made a start to try to remove the VERY well glued on engine nacelle-after about an hour with some alcohol (to soften the glue) and some steel rulers, and a scalpel I was able to separate the nacelle without major damage????. Since it’s too windy to fly over the next few days I’m going to slowly chip away at this job I think-I still have planes I wanna maiden this summer so it’s gonna be a slow project for those days I’m in the mood to work on it and I can’t fly for whatever reason. I’ve already sent a message to Dynam with photos and have requested replacement foam parts for the center section so I’ll see what comes of that next week before I get too deep into repairing this. Meanwhile though I will continue to remove the leftover glue on the parts so if I do end up restoring this one, I can do so without leftover glue being a nuisance. I really didn’t want another major project after my last Dynam plane turned into one (by choice), and here we have another????♂️.

Incidentally mine only had one large weight in the tail-it too had come unstuck and was loose in the box so six million dollar question is “does it need it”?? Also has anyone put an incidence meter on this plane to check the AOA of the Hori stab to see if it’s out of level??

I’m staying clear of RCG as too many idiots on there with conflicting opinions-I’ve found this forum to be considerably better for advice. Was really looking forward to getting and flying this plane-I’m just glad I never had to pay full price to get it to NZ or I would be REALLY hacked off being almost $400usd out of pocket (friend is a Dynam Agent so I get good prices and usually decent planes too).

If anyone has any repair tips/advice I’m all ears ok-see the pics for the issue with the Nacelle (now removed) and the moulding imperfection in the wing section on that side.

[xviper]

Builda, although what I see from your pictures, you may have gotten a worse than usual for Dynam, which is expected to have such issues. Rather than you getting "one bad one", I think it's more like some people get "one good one". It's Dynam afterall, and the price reflects a lower tier product line. My center wing section has never sat flush with the top of the fuse. Some people will shave this and that to make it flush but knowing that I bought a Dynam, I'm not fussed about it. The plane does fly adequately well enough. As for that weight, there are two back in the tail cone section. Many people have discovered at least one and sometimes both weights have come loose. Some leave one or both out and some have even gone in there and dug them out. They go as far back as you can get them. I gloop a pile of hot glue and shove it back there as far as my hemostats will reach. Does it need it? Well, that depends on what size battery you use and how far back you can secure it and whether or not you can balance the plane properly like that.
I can't offer much in the way of hints or tricks to repair your plane but it seems to me that you're on your way to getting it done pretty good on your own.
I've owned several Dynam planes, some worse than others but all of them have some sort of deficiency in terms of quality of foam, fitment and electrical issues (eg, retract that don't work when the temps get below ~60F, motor that stutter and ESCs that need to be reset, poor gluing). However, for the price, I've been very happy with Dynam and due to the price point, helped me move along in this hobby.

[Builda]

Builda, although what I see from your pictures, you may have gotten a worse than usual for Dynam, which is expected to have such issues. Rather than you getting "one bad one", I think it's more like some people get "one good one". It's Dynam afterall, and the price reflects a lower tier product line. My center wing section has never sat flush with the top of the fuse. Some people will shave this and that to make it flush but knowing that I bought a Dynam, I'm not fussed about it. The plane does fly adequately well enough. As for that weight, there are two back in the tail cone section. Many people have discovered at least one and sometimes both weights have come loose. Some leave one or both out and some have even gone in there and dug them out. They go as far back as you can get them. I gloop a pile of hot glue and shove it back there as far as my hemostats will reach. Does it need it? Well, that depends on what size battery you use and how far back you can secure it and whether or not you can balance the plane properly like that.
I can't offer much in the way of hints or tricks to repair your plane but it seems to me that you're on your way to getting it done pretty good on your own.
I've owned several Dynam planes, some worse than others but all of them have some sort of deficiency in terms of quality of foam, fitment and electrical issues (eg, retract that don't work when the temps get below ~60F, motor that stutter and ESCs that need to be reset, poor gluing). However, for the price, I've been very happy with Dynam and due to the price point, helped me move along in this hobby.

Hey dude, cheers for your input. I’ve got a number of Dynam birds and I concur, we buy them knowing that we will likely need to sort out a motor, or retracts, or maybe some paint issues (that’s how my Waco mods started-paint issues), my hellcat needed a power upgrade and retract upgrade, I’ve still got 4 Dynam planes I have yet to build, and unlike my FMS Tigercat (which is better than perfect out the box), I’ve always had to do something to a Dynam-but never have I had a n issue like this with the moulded parts! The last time I had an EPO plane with a moulded part is due like this it was actually a Horizon hobby plane! (Parkzone Trojan). The canopy would not fit the fuselage due to the bad moulding, so it’s not just Dynam that have the moulding problems. That out the way, I’ll better assess it over the next few days because as nice as it would be if Dynam replace the parts, I REALLY don’t want to have to rebuild an entire wing section.

the other issues with the plane I expected...cause it’s a Dynam-the hatch doesn’t fit flush, the plastic covers on the guns either side of the Fuselage are falling off, and the other one was the rear machine guns-it looks like someone forgot to put them in before they glued up the fuselage then tried to force them in through the hole in the fuselage-breaking both of the guns in the process!! That’s actually a good thing because I will fill this hole now and to be honest I think those guns would be a nuisance catching on things in the car all the time. So yea, it had its fair share of typical Dynam issues (and I’m yet to test the retracts I might add) but the nacelle was just too much to leave it as it was-I really didn’t want to pull it to pieces but it just wasn’t something I could live with.

ill have another look for weight in the tail but the fuse is pretty light now with everything removed-I’ll try to get this lump of steel glued back in as far back as possible.

my other Dynam birds I have awaiting build are an Me262 (I’m going 12 blade FMS conversion on this and full retract upgrade), an BF110 (needs ESC cooling sorted out the box same as Me262) a hawker tempest (will need the same power upgrade as my hellcat and probably retracts), and a hawker hurricane (which I may just sell online cause I have enough to do with the rest). I’m half tempted today to build my “La Patrona” Tigercat just to give me a morale boost but I think it will have the opposite effect! Lol!

[xviper]

I also have the FMS Ticat. When you build it, you will quickly see how it WILL put the B-26 to shame but then, the Ticat is in a whole other price point ball park. The Ticat's retracts are things of beauty and you will marvel at how they work. You should find very little, if anything, needed when putting the F7F together. It flies so much better and with a lot more authority. Having said this, you should also find that BOTH planes will land like they were on auto-pilot.

[themudduck]

I guess I will chime in - there's LOTS of info earlier in this thread about the weights, balance, stab incidence, and so on. And some conflicting opinions as well.
I would certainly recommend going through the earlier posts, when we were going through initial impressions and flight testing.
I went through all of the fixing with the bad construction and bad fit and hatches and so on

(check the wing attachment points in the fuse)

, but I really like the way my B26 turned out. Its a really nice-flying unique model and has a great look.

I did these things:

- used a smaller battery and no tail weights. Result is a lighter plane (less wing loading). I can fly well over 12 minutes using a 3600.
- balanced it a little further forward than most in this forum (I did a lot of flight testing). Tail-heavy B26 is a BIG BIG no-no. "The Widowmaker" will get you if you don't pay attention.
- shimmed the stab TE up several mm. This helped a lot with overall flying characteristics
- cut down the control throw on the elevator in particular.
- replaced the race-car wheels with Robart wheels - and I installed a slightly larger nose wheel to raise the nose, this gives the model a slight positive (and prototypical) AOA while on the ground.
- I always take off with half-flaps and land with full flaps. Without the flaps, the model will snap in a heartbeat at lower speeds.

Sadly, I left the toy pilots in the office. but I repainted them and gave the pilot a mustache and flying wings!

[Mrdronenut]

Thanks MD. I've not yet had an opportunity to maiden mine,along with 3 other planes due to health issues,and very windy conditions. Let me throw in before I forget(66yr old brain) that I've got the P-61. My advise.....get one. Mine has all the problems stated in the other forums,.gaps,big gaps,gaps....oh,glue everywhere,really really weak booms,did I mention gaps? That being said,it's an awesome looking plane. I'll maiden it this week,along with my B-26,which is ready for deployment.