Date: Thu, 26 Jan 1995 18:49:41 -1000 From: james@george.ankeny.ia.us (James Shoemaker) Message-Id: <791182181james.james@george.ankeny.ia.us> Organization: Organization for creative time-wasting Subject: Re: Weighting down yer buggy In article johnsen@eskimo.com (Brian Johnsen) writes: > While attending the Oregon Kitemaking Retreat, late in the evening, >some of the buggiers were telling lies, some half-truths and bemoaning >the fact that they need more weight in the nether regions in order to >keep the buggy in contact with the ground. > > Several solutions were kicked around, like carrying tanks of water or >strapping on diving weights or trading posteriors with someone else >who was only using it to hold down the sofa. > > This has all been percolating in the back of my mind until today >when I remembered how those big 4wd logging skidders are weighted. >All four of those huge tractor tires are filled with calcium before >being mounted to the wheel. > > This method could probably be used in buggies that use the wide >wheelbarrow tires. Just fill the tire 3/4 with sand before mounting >and inflating the tube. This may help with puncture resistance as well. > I have never seen Sand/Cancium tire weighting, but I have dealt with Fluid filled tractor tires (check with your local farm supply store). I would think sand could shift and cause a nasty wobble/bounce at speed. Fluid naturally balances itself. ------------------------------------------------------------------------------- James Shoemaker james@george.ankeny.ia.us One man's Windows are another man's walls... ------------------------------------------------------------------------------- = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Thu, 26 Jan 1995 15:34:00 -1000 From: johnsen@eskimo.com (Brian Johnsen) Message-Id: Organization: Cap'n Puget's Roadside Tako Stand Subject: Weighting down yer buggy While attending the Oregon Kitemaking Retreat, late in the evening, some of the buggiers were telling lies, some half-truths and bemoaning the fact that they need more weight in the nether regions in order to keep the buggy in contact with the ground. Several solutions were kicked around, like carrying tanks of water or strapping on diving weights or trading posteriors with someone else who was only using it to hold down the sofa. This has all been percolating in the back of my mind until today when I remembered how those big 4wd logging skidders are weighted. All four of those huge tractor tires are filled with calcium before being mounted to the wheel. This method could probably be used in buggies that use the wide wheelbarrow tires. Just fill the tire 3/4 with sand before mounting and inflating the tube. This may help with puncture resistance as well. Fundamentally yrs; -- Homemaker, Stoned On Beer, Bites Fifty-Three Personages Police Round Up Usual Suspects -- -- O= '|\ Brian Johnsen johnsen@eskimo.com Seattle, Washington USA = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Fri, 27 Jan 1995 08:56:43 -1000 From: Adrian Pierorazio Message-Id: Organization: Queen's University, Kingston Subject: Re: Weighting down yer buggy There's a problem with the weighting of your wheels compared to simply weighting your butt (or buggy). The problem is the mass moment of inertia of the wheels could increase drastically not to mention the possible instability incurred by partially filling your tires with some medium whether it be liquid or powder (weight shifting could cause some serious wobble at speed). For the non-technically trained out there the mass moment of inertia is like the rotational version of mass--objects with high MMI's are proportionally harder to start and stop than those with lower MMI's. This means that you may experience a drastic reduction in your starting acceleration (during which your arms will get very sore) and will coast for a lot longer when the pull of your kite is reduced (this is when you either over-run your kite or plow into someone/something that probably wouldn't appreciate it). Even more interesting is if you fill your tires with water--the water will gain momentum as you're rolling and when you stop, it will continue whirling for a while inside the tire. This may be enough to start the buggy rolling again if you stop applying the brakes too early. There are, IMHO, a few ways to improve your traction on a buggy: 1) Put weight as far away from the centreline of your buggy as possible (this will increase the rotational inertia of your buggy making it harder to start it rolling) 2) Angle your rear tires so that the tops are slanted towards the centreline of the buggy. This will give you better 'bite' on the inside and prevent you from sliding as much (skinny tires will have more of an effect than fat ones) This will change the wear pattern on your tires but, so long as you rotate them regularly, this may actually improve the life of your rubber. 3) If possible, lengthen your rear axle. The longer the lever arm between your downwind tire (pivot point) and you (the weight to be lifted), the harder the kite has to pull to flip you--therefore you can get more pull without flipping. 4) Treads/spikes, etc will improve grip of the buggy but this may lead to *more* flips than without (same as point 2). 5) Lowering the point that the kite's pull is applied (i.e. your hands) again reduces the lever arm the kite can use to pull you over compared to the righting moment of you at a distance of approximately 1/2 your rear axle meaning you can use more kite pull without flipping. Disclaimer: I don't buggy 'cuz I can't afford it and I prefer low to no wind flying in general but, I have done a significant amount of work in engineering dynamics and I may (or may not) have some valid ideas about how to improve buggies. I do not advocate the modification of a pre-built buggy by untrained personnel as this may incur significant safety risks. The preceeding ideas were random babblings and have not been analysed in any depth. Please do not take them as the official recommendations of an engineer of any sort (<--this is to cover my ass and practicing licence if one of you kills yourself implementing one of my ideas). Tight Lines and Upright Buggies, Adrian +-------------------------------+---------------------------------------+ | Adrian Pierorazio | | | Research Assistant | **** | | Queen's University | THIS | | Mechanical Engineering | SPACE | | Kingston, Ontario | FOR | | K7L 3N6 | RENT | | CANADA | | +-------------------------------+---------------------------------------+ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Fri, 27 Jan 1995 11:18:03 -1000 From: andrew@tug.com (Andrew Beattie) Message-Id: Organization: /usr/lib/news/organisation Subject: Re: Weighting down yer buggy In article johnsen@eskimo.com (Brian Johnsen) writes: > While attending the Oregon Kitemaking Retreat, late in the evening, >some of the buggiers were telling lies, some half-truths and bemoaning >the fact that they need more weight in the nether regions in order to >keep the buggy in contact with the ground. They were pulling your leg. The heavier the buggy is, the more difficult it is to make the buggy accelerate as quickly as the pilot, and hence the more often you leave it behind. Too much weight and you find yourself first standing on the pegs, then leaving the buggy behind. We're looking at spun alloy wheels and trying to find tyres with fewer plys to get the weight *down* (to say nothing of the guys who go round scrounginf bits of titanium pipe...) Andrew -- Read the Kite FAQ's: ftp.hawaii.edu:/pub/rec/kites/faq o /\ Kite Jumping: For sale: Prototype Keelless Rowlands Flowform. 2.3m^2 |_ \/ If you want 2.3m^2, Spectra Bridle, Flo-Yellow Carrington Fabric, US$80 (_\ to fly, use a >>Kite Fliers Site: http://www.kfs.org/kites<< andrew@tug.com Hangglider = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Sat, 28 Jan 1995 05:30:41 -1000 From: rlhaas@pylon.com (Robin Haas) Message-Id: <3gdnv1$5qv@earth.com> Organization: The Pipeline Subject: Re: Weighting down yer buggy johnsen@eskimo.com (Brian Johnsen) wrote: > > While attending the Oregon Kitemaking Retreat, late >in the evening, some of the buggiers were telling >lies, some half-truths and bemoaning the fact that >they need more weight in the nether regions in order to > keep the buggy in contact with the ground. > > Several solutions were kicked around, like carrying >tanks of water or strapping on diving weights or >trading posteriors with someone else who was only >using it to hold down the sofa. Hey, I walked into a room late at night while attending the conferance. It sure looked like the kind of group that would be standing around telling lies to me. Anyhow, when I walked in someone said, "There's one now." Could it have been my posterior they were referring to? Further investigation into this matter is needed!! Robin Haas = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Sat, 28 Jan 1995 00:15:35 -1000 From: crowell@teleport.com (Carl Crowell) Message-Id: Organization: Kites By Carl Crowell Subject: Re: Weighting down yer buggy johnsen@eskimo.com (Brian Johnsen) writes: > This method could probably be used in buggies that use the wide >wheelbarrow tires. Just fill the tire 3/4 with sand before mounting >and inflating the tube. This may help with puncture resistance as well. Yer wheels will act screwy at higher speeds, try clipping a lead bar under the rear axel. an easy way to add BIG KGs to the lowest most stable point. carl ___________________________________________________ email: crowell@kite.com FTP: ftp.teleport.com/pub/users/crowell WWW: http://www.teleport.com/~crowell Kites By Carl Crowell - O.S.F.M. World Headquarters = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Tue, 31 Jan 1995 09:36:59 -1000 From: andrew@tug.com (Andrew Beattie) Message-Id: Organization: /usr/lib/news/organisation Subject: Re: Weighting down yer buggy Adrian Pierorazio writes: >There are, IMHO, a few ways to improve your traction on a buggy: > 2) Angle your rear tires so that the tops are slanted towards > the centreline of the buggy. This will give you better > 'bite' on the inside and prevent you from sliding as much > (skinny tires will have more of an effect than fat ones) It also slows you down due to tyre-scrub. I dispute the assertion that it provides more grip and request experemental proof. Land-yachts tilt the wheels so that they are vertical when on 2-wheels Wheel chairs tilt the wheels to more comfortably fit more wheel under the arm-pit (and perhaps to increase track) > 3) If possible, lengthen your rear axle. Yes. However this makes it more difficult to get it on 2 wheels then you *want* to... So you must decide: more speed or more fun... > 4) Treads/spikes, etc will improve grip of the buggy but > this may lead to *more* flips than without (same as > point 2). Yep. Tread makes a significant difference. I've seen the tyre wear away a hollow in Philip McConnochie's arm - I think I'll pass on spikes :-) >I do not advocate the modification of a pre-built buggy >by untrained personnel as this may incur significant safety risks. Come the revolution, the lawyers will be first against the wall. If you've got an idea, try it out, learn, share, learn more! Andrw -- Read the Kite FAQ's: ftp.hawaii.edu:/pub/rec/kites/faq o /\ Kite Jumping: For sale: Prototype Keelless Rowlands Flowform. 2.3m^2 |_ \/ If you want 2.3m^2, Spectra Bridle, Flo-Yellow Carrington Fabric, US$80 (_\ to fly, use a >>Kite Fliers Site: http://www.kfs.org/kites<< andrew@tug.com Hangglider = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Wed, 1 Feb 1995 17:47:37 -1000 From: johnsen@eskimo.com (Brian Johnsen) Message-Id: Organization: Tethered Airfoil R&D Pty. Ltd. (C) (R) (TM) CD CASS Subject: Re: Weighting down yer buggy In article <3gdnv1$5qv@earth.com>, Robin Haas wrote: >johnsen@eskimo.com (Brian Johnsen) wrote: >> While attending the Oregon Kitemaking Retreat, late >>in the evening, some of the buggiers were telling > >Hey, I walked into a room late at night while attending the >conferance. It sure looked like the kind of group that would >be standing around telling lies to me. Anyhow, when I walked >in someone said, "There's one now." I'm pretty sure I wasn't involved in that one, as we were outside at the time in the dark & personally, I was thinking seriously of going to get a heavier coat. However there was much whooping and hollering occuring which was too interesting. I've got a cold now. -- Bolivian Cosmetologists Discover Lost Constellation Of Capitol Hill -- --Brian Johnsen johnsen@eskimo.com Seattle, Washington USA = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =