no more metal bearings?

[ray schrauwen]

http://polygoncomposites.com/product...FcO1wAodYvYAYg

Interesting stuff. I need to read it more, just sharing.

[CraigP]

We have dabbled in ptfe and FG bearings in GP hydros. We found some concerns:

1) They are meant to be used in a “dry” environment. No greasing, but no water either.
2) They don’t like very high rpm shaft speed
3) Water is not a good lubricant, in fact, it’s abrasive. That’s why they use water in water jet cutting tech.

The dilution of lubricant by water, as is the case with unsealed struts, is a constraint that must be taken into account. That’s why soft metal bearings, such as the floating bearing, have worked so well.

I run a sealed strut, so I don’t have the water issue. But I don’t think this would be any better than the Teflon/lead bushings in my application. If you maintain proper lubrication and balance your blades, the bushing will have a very long life. That’s my two cents worth...

[rol243]

yes nothing wrong with the good old Lead Teflon Bushings, they are cheap and when they need replacing just pop them out and pop in some new ones. lubrication is the bushings friend.

[Fluid]

The problem with lead Teflon bushings is their cheap manufacture. They are not really “round” and they have a gap so they do not provide 360* support to the shaft. The film of Teflon is very thin and wears off easily when inserting and removing the cable. Because everyone lubes the bushing anyway, the loss of the Teflon coating is often missed. (Poured-lead bushings have been used for a century in full-scale boats but for model boats lead-on-steel at high rpm is not the best solution.). A higher quality, more robust Teflon bushing would be welcome. ‘Cheap’ loses its appeal if it has to be replaced often - and usually too late...


.

[Shooter]

Similar to what was mentioned above, the biggest problem I've had with lead teflon bushings is tolerances and variation from one vendor to another. They need to be accurate at both the OD (press fit) and ID (clearance fit). I still use them in all my struts, but finding parts that fit have been a challenge lately!

[ray schrauwen]

Thanks for the input guys. I guess I'll stick to Speedmaster for awhile.

[rol243]

when your running 3/16 inch shafts you need to be sure the strut bushing used is also 3/16 inch i.d. and not 5mm like many are sold as a 3/16 bushing but there really 5mm. genuine 3/16 inch lead teflon bushings can be obtained from Aeromarine suppliers. most of the 5mm bushings come from china etc.

[ray schrauwen]

Hate to say but the Chinese ones are terrible, at least ones I tried once. Some like in a TFL strut are better.

[Shooter]

when your running 3/16 inch shafts you need to be sure the strut bushing used is also 3/16 inch i.d. and not 5mm like many are sold as a 3/16 bushing but there really 5mm. genuine 3/16 inch lead teflon bushings can be obtained from Aeromarine suppliers. most of the 5mm bushings come from china etc.

Thanks, and good observation.

[rol243]

same goes for Flex Shafts, are you using a 5 mm or 3/16 shaft with the correct strut bushing i.d. many shafts are sold as a 3/16 or 1/4 inch o.d. size but there a metric size as in 5 mm or 6.5 mm.

[kfxguy]

Hate to say but the Chinese ones are terrible, at least ones I tried once. Some like in a TFL strut are better.

Tfl no Chinese?

[Shooter]

same goes for Flex Shafts, are you using a 5 mm or 3/16 shaft with the correct strut bushing i.d. many shafts are sold as a 3/16 or 1/4 inch o.d. size but there a metric size as in 5 mm or 6.5 mm.

Kinda stings, but it really brings some reality to all of this. As most of the world sees it, they are just toy boats, and it's 'close enough'.

[fweasel]

Tfl no Chinese?

Your English is improving

[kfxguy]

Your English is improving

Lol

[NativePaul]

New, but gaining popularity with racers in Europe are Ketron HPV bushings, Ketron HPV is a PEEK plastic impregnated with carbon for wear resistance, PTFE for friction reduction and graphite for lubrication.