Fingertip prop balancer

[john66]

Hi Chaps

Just bought a Fingertip prop balancer cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290430124017

I think I get the idea with a two blade and am under the impression that its better to add weight to a lighter blade than remove from a heavier, any thoughts?

Also can I use this for balancing 3 blades? I intend to try them out on my spit for more scale MKII looks, I have ordered 2 x 3 blade GWS props 1 x 9x5 & 1x 8x4 and want to dip/paint the tips so figured could balance with that.

If suitable for 3 blades any tips would be appreciated.

Thanks, John

[ginginho]

May 19, 2010 12:09:41 GMT 1 @john66 said:

Hi Chaps

Just bought a Fingertip prop balancer cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=290430124017

I think I get the idea with a two blade and am under the impression that its better to add weight to a lighter blade than remove from a heavier, any thoughts?

Also can I use this for balancing 3 blades? I intend to try them out on my spit for more scale MKII looks, I have ordered 2 x 3 blade GWS props 1 x 9x5 & 1x 8x4 and want to dip/paint the tips so figured could balance with that.

If suitable for 3 blades any tips would be appreciated.

Thanks, John

It'll be interesting to see what size the bar is, as the wording suggests it's for IC primarily. A lot just use a bit of CA (superglue) or nail varnish on the back of the lighter blade, which seems to be successful enough unless it's wildly out of balance.
With a 3 blade, you'll either get one that's heavier (hangs below) than the other two, or one that's a lot lighter (ends up on top after each spin). In the first case, you could add a small amount to the two others, in the second case, add some weight to that one. Simples! ;D

Clean off any moulding cr@p all over the prop before trying to balance it.

[john66]

May 19, 2010 12:56:35 GMT 1 ginginho said:

It'll be interesting to see what size the bar is, as the wording suggests it's for IC primarily. [/quote]

Dammm dunno why that didnt sink in, does that mean no good for electric? Thanks for the 3 blade balancing tips.

John

[ginginho]

May 19, 2010 13:34:46 GMT 1 @john66 said:

May 19, 2010 12:56:35 GMT 1 ginginho said:

It'll be interesting to see what size the bar is, as the wording suggests it's for IC primarily.

Dammm dunno why that didnt sink in, does that mean no good for electric?

Only if it's too big. Fingers crossed!

[flydiver]

I've go 2 similar looking ones. Both have a 4mm shaft so too big for the 3mm hole props. I just use a small nail I lopped off the head and spun it in a drill to file the ends to a point. A bit of tape to make a snug fit in the hole and it works OK.

If you have a suitable bench vise you can mount a couple of strong magnets in the jaws at the same height and turn it into a magnetic balancer.

[john66]

May 19, 2010 15:02:27 GMT 1 flydiver said:

I've go 2 similar looking ones. Both have a 4mm shaft so too big for the 3mm hole props. I just use a small nail I lopped off the head and spun it in a drill to file the ends to a point. A bit of tape to make a snug fit in the hole and it works OK.

If you have a suitable bench vise you can mount a couple of strong magnets in the jaws at the same height and turn it into a magnetic balancer.

The motor I have has a 4mm shaft, does that mean I should be ok?

John

[ginginho]

May 19, 2010 15:02:27 GMT 1 flydiver said:

I've go 2 similar looking ones. Both have a 4mm shaft so too big for the 3mm hole props. I just use a small nail I lopped off the head and spun it in a drill to file the ends to a point. A bit of tape to make a snug fit in the hole and it works OK.

If you have a suitable bench vise you can mount a couple of strong magnets in the jaws at the same height and turn it into a magnetic balancer.

There ya go John, should be ok for most things. Your XYH's have a 4mm shaft I think. I do the magnet trick with a drill bit, it get's em close enough.

[skivit48]

If the hole on your prop is also 4mm you should be fine. Not sure about what to do if it isn't.

I would think you could drill out your prop holes to 4mm but it would need to be centered exactly and probably best done with a drill press than by hand.


I just ordered the same type of balancer from Headsuprc. The shaft on this one is 3mm so I should be ok. Except the cub prop shaft is 4mm, and I will have to drill out the propeller hub to make it fit.

Uh-oh now I am getting confused.
Any suggestions?


Another noob who isn't even close to knowing it all here.

[ginginho]

May 19, 2010 16:35:29 GMT 1 skivit48 said:

If the hole on your prop is also 4mm you should be fine. Not sure about what to do if it isn't.

I would think you could drill out your prop holes to 4mm but it would need to be centered exactly and probably best done with a drill press than by hand.


I just ordered the same type of balancer from Headsuprc. The shaft on this one is 3mm so I should be ok. Except the cub prop shaft is 4mm, and I will have to drill out the propeller hub to make it fit.

Uh-oh now I am getting confused.
Any suggestions?


Another noob who isn't even close to knowing it all here.

Most (but not all) non-stock props come with adaptor rings allowing them to fit to a variety of shafts that are smaller than the hole in the prop hub. If the hole in the prop is too small for your shaft then you are correct, you need to drill it. A press is the best way, and find some way of mounting it so that the hub is flat to the bed, as the blades often interfere with this. I use a large-ish nut (18mm outside diameter roughly, from some plumbing stuff I had laying around) as this raises the whole prop off the drill bed without touching the blades and keeps the hub level to the press bed.

[john66]

Thanks for your replies chaps.

John

[flydiver]

Drill press - disagree. They are too aggressive and if you don't line things up PERFECTLY you will drill a really nice off center hole.
Hand reamers are just that > hand. Slow, tedious sequential removal of material to make it the size you want.

I've got a really nice BIG drill press. I don't use it for that anymore.

[ginginho]

May 19, 2010 18:20:56 GMT 1 flydiver said:

Drill press - disagree. They are too aggressive and if you don't line things up PERFECTLY you will drill a really nice off center hole.
Hand reamers are just that > hand. Slow, tedious sequential removal of material to make it the size you want.

I've got a really nice BIG drill press. I don't use it for that anymore.

Good point Fly, and worth noting if anyone is thinking of attempting this.
I am ever-so careful lining it up and ensure that the bit is cutting on the full circumference of the original hole before gently plunging through. I guess the technique is OK as I've not messed one up in a long time (I started by practicing on broken props until I got a process that worked), although I don't think I've had to do one for many months now...My landings must be improving. ;D

EDIT: I've read in quite a few places that APC props actually have the hole off-centre by intention, allowing the centreing of the prop on the shaft using one of the reducer rings. I don't have any real APC's (only clones and these are not like that) to verify this.

[john66]

Balancer & 3 blade props turned up 10 min ago. The balancer has a 3mm spindle and uses the two cones to slide up and fill the reccess. Even on the electric props with no adapter rings inserted the spindle is way too small its dia is only 3mm. With correct adapters it fits snugly but freely on the balancer. ;D

Thanks again for the input on balancing.

John

[ginginho]

John,
I think you are supposed to use the cones to "pinch" the prop between them, ensuring that it is centred but not actually touching the shaft. You can then spin the whole lot between the end points, use magnets as Fly suggested for a near frictionless setup. If you have some and a big enough vice, place one magnet on one vice jaw and open it up further than is required to install another on the other jaw and the balancer inbetween. You then hold the shaft to one magnet with the length pointing to the other, and (slowly) wind the jaws together until the shaft is attracted to the other magnet but not touching, but floating a few mms off it (held by the magnetic force). There is only one friction area for the whole balancer, being the one point of the shaft that is touching the first magnet.

(Question to self, why do I always type magent when I mean to type magnet?)


Hopefully the tool is well balanced so the only weight differential is the prop blades themselves.

[john66]

May 20, 2010 13:28:26 GMT 1 ginginho said:

John,
I think you are supposed to use the cones to "pinch" the prop between them, ensuring that it is centred but not actually touching the shaft. You can then spin the whole lot between the end points, use magnets as Fly suggested for a near frictionless setup. If you have some and a big enough vice, place one magnet on one vice jaw and open it up further than is required to install another on the other jaw and the balancer inbetween. You then hold the shaft to one magnet with the length pointing to the other, and (slowly) wind the jaws together until the shaft is attracted to the other magnet but not touching, but floating a few mms off it (held by the magnetic force). There is only one friction area for the whole balancer, being the one point of the shaft that is touching the first magnet.

(Question to self, why do I always type magent when I mean to type magnet?)


Hopefully the tool is well balanced so the only weight differential is the prop blades themselves.

Ok I think I get what you are saying, I guess it would be better to use the prop adapter for a 3mm shaft then to balance it then switch to the 4mm for my shaft afterwards? Unfortunately I dont have a vice nor magnets or magents if you prefer? . I use a bench sized B&D workmate (no legs) as my vice at the mo, though a proper vice is on the shopping list.

Thanks again ginginho.

John