Longer boom options and torque tube

[trillian]

I wanted to be able to try longer blades on my RMJ Raptor and looked into getting a longer boom and this is what I found:

First of all, there's the proper Raptor long boom for the E700 that comes with a longer tail control rod. However, I was not seeing a torque tube to go with it. I heard you can use the G4/E720 TT but everywhere I looked they were out of stock.

In any case I ordered the longer boom but unfortunately it arrived bent, no doubt due to something very heavy being dumped on it in transit.

I then discovered that the Blitz Avro boom will fit, it's exactly the right diameter and is about 6mm longer than the Raptor 'longer' boom. It just requires drilling a new hole at the tail end and cutting slots in the front end as well as a hole for the pin. I happened to have a spare Avro boom already so I used it rather than wait for a replacement for the item I received damaged.

Then on to the torque tube. If you can turn down the Raptor TT end pieces slightly you can use an Easton Arrow shaft (and you can get the shafts up to 32 inches which is longer than you need). But I discovered that the Trex 700 DFC TT will fit, the ends are slightly different but they fit perfectly on the Raptor. The TT comes with two bearings so all you have to do is fit the Raptor plastic holders on them. I didn't want to take apart my other TT but I had some spare Trex rubber TT holders and they're a bit smaller to fit the Trex boom but all it takes is a bit of loom tape or bicycle grip tape or similar to add a little outer diameter to them so they fit snug inside the Raptor boom.

Anyway, some of this may be common knowledge but as I had not seen anything prior about the Trex TT fitting the Raptor I thought it's worth mentioning.

I will say, as I didn't try to fit the actual Raptor longer boom I'm not 100% sure if the Trex DFC TT isn't too long but I think, given that the Avro boom is only about 6mm longer, it should work. It just may require having the Raptor long boom ever so slightly pulled out, which would mean re-drilling the hole for the pin screw but that's really no biggie and may not even be needed.

I can say for certain though that the Avro boom fits and easily allows running 720mm mains and 110 tails. I still have 105s on the tail and haven't flown it yet so if the tail is fine I'll leave it as-is.

[Si Goodchild]

Does that mean you've solved the spares issue for E720 owners who prang their tail boom?

Si G

[trillian]

Does that mean you've solved the spares issue for E720 owners who prang their tail boom?

Si G

The E720 boom is a larger diameter (3.4mm larger), so the Avro boom would need something added to the outside at each end to fit snugly. I think the Logo Xtreme boom will fit, just would need to be cut down to the right length.

[trillian]

Just to add a little detail: I took off the tail to double check the slack in the torque tube and there's about 3mm of slack with the Avro boom.

This means that with the Raptor 'long' boom the Align TT will be ever so slightly long, but there are two ways to overcome that, 1st by running the Raptor boom out slightly in the front, just drill a new hole for the pin a few mm in front of the existing one so you can pin it in place. The 2nd way would be to shave a bit off the TT ends as you have a good 13 or so mm of splines so it's not going to hurt trimming off a few mm on each end (or just one end to make the other end easier to fit, so maybe leave it at the front and then chop some off at the tail side).

[Guest]

Custom Carbon boom, E720 TT, Synergy carbon pushrod with custom carbon tail servo bracket. Swings 711's, 105 tails, 4.71 tail ratio. Here is an inverted auto hang time is superb. Rtf weight 5.3kg less fuel.

https://youtu.be/ZwTFtxa5Jpk

MJ

[trillian]

Looks good! Mine is a little heavier at 5.47kg but I have the pullstart attached and heavy main blades at the moment. It doesn't feel heavy in the air though and that's what counts.

---- just thought of something--- is that weight of 5.3kg without a canopy? I weighed mine with the canopy and the canopy weighs about 188 grams, but my tank is completely dry.

The Century Predator I had was great for autos, I'm not sure why. It was a bit heavier and still had a flybar and I flew it with Radix 710s and it was so easy to auto.

Speaking of tail pushrods, the ones that come with the Trex 700 are so nice, it started me thinking about looking into adapting one for the Raptor but for now the regular steel rod does the job well enough.