450 sport tail block issues

[challis349]

Hi all,

I've flown 3 packs through my 450 and on the start of the 4th noticed the vertical fin wasn't straight so landed and checked it out, I found the boom was loose, and no matter how tight I do the screws, it just won't tighten up, does any body else have this issue? Or anybody know of a solution, its causing obviously the belt tension to go, and the boom to twist very slightly, which is playing havoc on the rudder/tail

Cheers

[bigpops]

Assuming the threads aren't stripped, what about wrapping some tape round the boom? PTFE tape would do, or black insulation tape. Trim off any that's sticking out of the block. If the boom is twisting, maybe the rotation pin from the inside of the boom block has gone missing?

If the threads are stripped, then new hexagonal bolts are in order (45HT003).

Tarot also do a metal boom block, but I don't know if it's any better than the plastic one that ships on the sport.

[challis349]

Thanks for the reply, one of the threads has now stripped, but they are metal inserts which are replaceable between the 2 halves of the boom block, but this has only stripped whilst trying to stop the boom moving

[challis349]

Ok, so choices from hf....
1. Split the tail block and sand away some of the plastic, meaning for a tighter fit, but don't know if metal inserts will need shortening a touch.

2. Tape round the boom, although surely won't be massively strong.

3. A spare servo ARM bred up to tail block, which won't stop my slight twisting


Any more ideas people

[BiG-T]

Hi
Funny enough I have the same problem with my 450 sport noticed it today on the 3rd pack the boom twisting away from the tail rotor, it seems to be twisting from the front block all the bolts are tight. need to take the block apart and try a turn or two of insulation tape to see if that will stop it happening.

Tony

[heliboy]

buy a new boom block dude.

all the trouble ..just buy a new one.

[acwman]

Unfortunately it seems to be an inherent problem with the sport. I myself just ran the both halves of the boom block on some wet n dry paper to take away some material. Have not had any problems since.

[Hakiem]

it is normal to have a loose boom block. this happens because if you land so hard your boom block start to loosen up bit by bit. so what i did is just drill a small hole in the boom block. and insert one screw. then once you start to screw it, it will create a hole in the boom, since it is just aluminium. basically after doing this modification, you wont have that problem again. hope that help you. cheers.

[pDidd]

There should be a little plastic tab on the left side of the boom block looking from the rear to keep the fin vertical, Ive had a couple of them break off.

[amh]

I agree that this is a problem that most have with the sport. To get the belt tension correct the plastic tab is not slotted in the boom.

I went for the cheapo option with tape round the boom. Loosen the boom block mounts off completely and pull the block apart and with the boom taped up push it in and then tighten it all up, you'll be surprised at how sturdy that can get it.

But you may want to consider changing the cheesium screws before doing this or they will round off very easily.

[challis349]

Lol, already changed the Damn screws, they were a right bugger, will tape boom and fly again lol

[heliboy]

Just to resurface this issue,last Tuesday night after flying one pack and the tail blowing out on several inverts i landed and noticed the belt has come loose as in the boom had slipped.so after tightening it did the same.So i now have the servo tail servo arm butted up against the boom block.However now i need to buy and extended tail rod OR buy another tail servo mount and butt that up against the boom block and then it cannot move..

[mickwilliams36]

This is definitely a common problem on the 450 Sport as I've had exactly the same trouble with mine. The boom kept on slipping into the boom block, loosening the belt. After I wrapped a couple of layers of sellotape around the boom the problem never came back.
I've since fitted a S9257 onto the tail. Now the increased size of the servo (used to be a Savox SH0257MG) means the servo support arm is hard up against the boom block and it's as solid as a rock.

Cheers,

[heliboy]

This is definitely a common problem on the 450 Sport as I've had exactly the same trouble with mine. The boom kept on slipping into the boom block, loosening the belt. After I wrapped a couple of layers of sellotape around the boom the problem never came back.
I've since fitted a S9257 onto the tail. Now the increased size of the servo (used to be a Savox SH0257MG) means the servo support arm is hard up against the boom block and it's as solid as a rock.

Cheers,

Yes Mick i share the sentiment.I run a ds520 so theres a gap.But the extra tail servo support will do it..

[nitromad]

i had this problem also i just got the metal one and make steel inserts and used steel blots not shifted since