Official Dynam 1500mm B-26 Marauder Thread

[rifleman_btx]

Tomcats are a Dynam product name

[quitcherbitchen]

Well, one little problem---When I rebuilt the 26 with the new fuse, I kinda glued the tail section on----Can't shim! Any suggestions???

Bob I would strongly suggest that you not try bending the tail. The shim changes the incidence which is the angle of attack for the horizontal stab. Bending or warping the stab may not give you the result you want because the AOA (angle of attack) remains the same for the leading edge. I would suggest what Ryan suggested and just put in more up trim. Dial down the elevator throw to the nearest hole on the servo too.

[rifleman_btx]

Yes, you only need 1/2 inch of throw on the elevator. Anymore you lose the plane really quick from over control.

[CFIT rob]

Bob,Mine flys great with about 2mm up elevator and a heavy China hobbyline 4000mah 40c, one tail weight and a cg of 55 to 60mm. Moving my battery back just 1/4 inch from my marks it starts to drag the tail and make me pucker. Make sure your battery isnt moving aft on take off. I fly half throttle (ish)straight and level then boost it to 3/4 ish when im banking. Warping the stab is not necessary.

[Mad Baron]

I boxed mine up last night because of the retract issues and getting tired of looking at on my workbench. I have been in touch with MRC about the problems and hopefully a solution can be found. The retracts when extended or reacted I might have one or two work or not at all and the retracts keep resetting like when the plane is powered up.

[rifleman_btx]

Dang that sounds sound the y harness is bad. Because a mechanical problem or anything internal doesn't seem like it would totally reset like that.

[Mad Baron]

Motion sent me a new 3 way harness for the retracts. What puzzles me is when I plug in each retract separately they work just fine and I am using a full charged admiral 4000 4s to test them with

[rifleman_btx]

Ah ESC problem? Could you be getting brown outs in the receiver where the BEC isn't supplying the power it's supposed to for all the retracts to operate together? Do you have a separate BEC to test that, or possibly, if you have a spare ESC to test either way?

[Mad Baron]

I will try your suggestion on using a separate bec tonight I really would like to get this plane in the air soon because it's turning in to a hangar queen

[rifleman_btx]

Yes it's a great flying plane, I hope that gets it done

[Mad Baron]

Well I tried to connect a BEC to my receiver I am using a Gavin Rx and it has no port to connect a BEC I tried to use an open aux channel but the servos went crazy when I turned on the BEC. I double checked the connections from the Rx to the servos and the retracts started to work as advertised I am thinking it might have been a loose or bad connection.

[rifleman_btx]

Oh wow. Does this mean a trip to fly tomorrow?

[Mad Baron]

Unfortunately no. I have to work tomorrow hopefully this upcoming Wednesday or Thursday!

[rifleman_btx]

SWEET!

[quitcherbitchen]

Here are the bulkheads I made to make a Bomb Bay just in case anyone is interested in copying me. You might have to adjust for my imperfections. I noticed that my bomb bay wasn't completely centered. Not a problem.

[rifleman_btx]

Very nice! I like that

[warbirdbob]

Hey Guys---Thanks for all your advice!! I finally got a half decent flight out of the "Beast" yesterday (I think I'll make that the nose art name!) . I agree, I had too much throw in the elevator, and the up trim seemed to work. I see what you mean by the shim being the answer, but I think I can compensate for that. Yes, I'll move the servo rod to the horn to the bottom(top) hole. The take off is very squirrely but after achieving altitude and a bit of speed, it seemed to settle down. I was flying with both weights in the tail, and will remove one for the next try. Still broke a prop on landing, but will get more and keep trying until one of us doesn't survive!!!!

[DonRhone]

Regarding the shim to adjust the elevator.

Do the later production runs of the Dynam B26 also require the shim adjustment?

I would have thought that once that was the elevator angle was noticed that Dynam would have fixed the problem and only those with the first production runs would be required to shim the elevator.

[themudduck]

Regarding the shim to adjust the elevator.

Do the later production runs of the Dynam B26 also require the shim adjustment?

I would have thought that once that was the elevator angle was noticed that Dynam would have fixed the problem and only those with the first production runs would be required to shim the elevator.

...gets on soap box to bloviate:)

Actually these models are produced using steel injection molds which are extremely expensive. That's where all the investment is... once that mold is produced it's done. The mold can't be changed. The only way to fix it is to produce an entire new fuselage mold (actually two, since there's two halves) and that's just not going to happen because of the huge expense.

In rare cases you'll see them discontinue a product and then release a new version, but don't hold your breath for that to happen with the B26 - my feeling is that its not going to have multiple production runs. More likely, after some time on the market it will just go away and they'll move on to the next model. Sorry - that's a lot of "gloom and doom" from me but I have to say on the positive side, the "shim modification" is quick and super-easy and totally fixes the problem, so that's a very good thing.

...steps off soap box, goes back to work

[warbirdbob]

Was able to lift the back of the hoz. stab. to give it a little adjustment. Maybe enough to help the problem. We'll see---------