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KerrinRees - n/a
16-Apr-06, 08:49 PM
Hi,



Paraphrase a comment from Hoverchaps "Pillow blocks no good at top of drive system":



I have designed ours the same as srn4, the axial loading specs would imply no problem, what have I missed? is it the block or the bearing that causes concern?



Thanks,



Kerrin

jar2 - n/a
17-Apr-06, 08:20 AM
HI Kerrin,



I was tempted to reply to that comment as it's nonsense. The thrust load on hovercraft is pathetically small compared to the rated load of pillow block bearings.



The bearing housings can be either cast iron or pressed steel (much cheaper). The 25mm shaft cast housing can take a thrust load axial load of around 1800Kg and the pressed steel 600Kg - I haven't seen a hovercraft with that kind of thrust yet http://hovercraft.org.uk/images/icons/smiley_icons/icon_eek.gif If you use pressed steel then you need to take care to provide support for the housing as it does flex a bit under load (Either fit a tube between two housings or use the elliptical shaped flat type housing with the radial mount holes).

KerrinRees - n/a
17-Apr-06, 09:18 AM
Thanks John,



The nearest I could find to a definitive answer is the SKF site which gives max axial load as 20% of max radial, tons of headroom as you say.



Good luck,



Kerrin

Nick Long - n/a
17-Apr-06, 10:51 AM
Ordinary ball bearing races are very good for radial loads, but most will also take a large axial load. Tapered roller bearings are better for axial loads and that makes people forget that ball bearings will also work.



I would read the manufacturer's spec rather than the comments on the bulletin board.



Nick

andycollins - n/a
17-Apr-06, 04:13 PM
<table border="0" align="center" width="90%" cellpadding="3" cellspacing="1"><tr><td class="SmallText">Quote:</td></tr><tr><td class="quote">


I would read the manufacturer's spec rather than the comments on the bulletin board.
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Hmmm. Here speaketh the 4th most prolific poster http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif





Cheers.



Andy.

Nick Long - n/a
17-Apr-06, 06:14 PM
Hmmm. Here speaketh the 4th most prolific poster http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif






Now that's not fair; you tricked me into starting with a large count. And look at the people who have overtaken me since. (Come on Ewan, Tony, get to it.)



To paraphrase the Emperor Claudius: Isn't what a man says more important than how often he says it?



Nick

jon_curtis - n/a
19-Apr-06, 11:58 AM
tell that to that nutter atters!

richardevans - n/a
19-Apr-06, 01:12 PM
No way.



As my mum told me:

"It's not what you say, it's the way you say it".





Richard E.

Sean Atterbury - n/a
20-Apr-06, 06:31 AM
NUTTER ATTERS HERE, See I'm like Batman, chuck a signal into the air and whoom, there I am.... http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif



Sorry to dissapoint everyone but I have'nt had a chance to take the craft out lately, but I did take it off the trailer and drive it back on just for kicks.



Still contemplating my newest desaster, cant seem to find one that tops that last one.



BUT: I will not disapoint http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif



On the toppic,



Bearings work fine, If it's not broke, doen't fix it.

http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif