Belt conversion for MA Whiplash

[OldGasser]

Hi all of you,

I think I found a belt-solution, so we can lay the bevel-problem to rest:

1) Remove the 15x21x4 bearings from the front and tailcase.
2) if needed, grind off the bearing-seat with a file at the top and the bottom (tailcase) and left and right (front case) to give the belt some more room.
3) install the pulley and the belt. Flatten the shaft a bit for the setscrew.
4) use a second collar instead of the bevel to keep the shaft in place.
4) use the tailcase to tighten the belt. Can put some loctite medium on the tail-boom to avoid slipping.

Materials, from sdp-si.com:
- 2 pulleys A 6A 3M10DF09506, flanges with hub, bore size: 6 mm,
pitch diameter: 16.2 mm, for belt width 9,5 mm
- 2 collars A 7X 2M116060, steel, bore size 6mm,
- 1 belt A 6R A 6R 3M345080, belt width 8 mm, grooves 345, pitch length 1752,6 mm

Total cost approx 50,-- USD. Crash cost basically zero.
All stock parts widely available, no headache about replacements.

Some remarks:
1) As for the belt you may want to consider 343 grooves or 9,5 mm belt-width. You do the measuring & math.
2) Fiberglass cords are not ideal with small pulley-diameters and high speeds.
If you find a 345 grooves Polyurethan with Polyester-cords, please let me know.

Should be workable, what do you think?

Kind regards
George

P.S. If the solution is good, can we make this topic sticky for future reference af MA whippy owners?

[fastflyer20]

Good idea, now for someone to build it and see how it works.

The MA boom is 22mm, some of the belt drive helis I am familiar with use larger diameter booms when running belts.

The tail would need to be grounded to prevent static discharge issues.
Not hard to do, but necessary

[flyul1]

Good afternoon George, Sounds like a good idea. I like my Furion 6 belt drive.

Thanks

[OldGasser]

Hi Tom,

The RJX gasser has a 22 mm tailboom too. It uses a 6mm S3M belt which is longer than the belt needed for Whiplash. No issues so far.

Could convert the Whippy to an 800 with the RJX tail-boom.
Though, the pulles have a 5mm bore whit a pin and are not suitable to be adapted to the 6mm Whippy-shaft. Would have to get other ones.

Grounding is advisable when using carbon-booms. With aluminium-booms they are basically already grounded via the boom.

The XT format is the only one I found that has small enough pulles and a belt-lenght
suitable for the Whipplash boom. Most belts for formats with small pulles are either to short or have nothing in the 1740-1750 mm range.

If I only scrap out the bearing-seat of the tailset at the bottom and at the top I can always go back to TT. So nothing lost here. But I do not think I will.

Belts are cheaper, lower maintainance, low crash-cost plus faster crash-repair and even a small earth-contact with the tail-blades does no harm.
IMO TT is just a fashion and some money-making on the replacement parts.

Kind regards
George

[Dkindleysides]

I am interested in a set of gears

[OldGasser]

Hi together,

Got the parts from sdp-si.com. The whole construction leaves the belt quite close to the walls of the tube. So smaller pulleys than the 2 pulleys A 6A 3M10DF09506 are advisable.

OR:
Since I am using the RJX tailboom anyway I will get myself a belt-conversion for the RJX gasser. RJX has 5mm-shafts, so the shaft for the frontdrive will have to be adapted. I will be using a 5mm shaft, put an other tail-pulley (the RJX front pulley has a rectangular hole) on it and use a piece of 5mm/6mm tube to make it fit the 6mm bearings. This should do.

Kind regards
George