 | | Re: drawbridge
|
|
(...) I used a single motor, with all cables being passed above the top of the span to get to the far side (4 cables). One trick that I would do if I was building another one is to make the cable drums easier to adjust to one another, since they (...) (21 years ago, 30-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Vertical lift spans (was: Re: drawbridge
|
|
Not sure where to chime in, so I'll jump in here. Regarding the lifting of vertical lift spans: I've built many of these over the years and my latest version (yet to be published on the internet) takes advantage of an engineering survey done on one (...) (21 years ago, 30-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) I believe your are right Steven, if two identical motors were connected in an identical way they would run at the same speed provided they had identical loads. But nothing in this physical world is identical and that is why stepper motors and (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) Yes, roger that. I get it :-) I can easily write a sheet to do that. Actually, I have one! But it's geared towards an arched bridge with suspended deck. I'll get these sheets to the public soon! -TJ (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) well since i was basing my theory of working with stereos and lights on my car, you have the uperhand...lol (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
That might very well almost hold true (I am no expert) if your motors were hooked up like: [power]--------[moto...---[motor] (parallel circuit) But I have mine hooked up like: [motor]--------[powe...---[motor] (parallel circuits) I assume one motor (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: Lego track cleaner
|
|
I uploaded the page - it is originally made my Joe Davenport. I was looking for it, and he sent me the pictures lately as he does not have a homepage anymore. (URL) this one too (URL) Jensen <sonnich@hot.ee> wrote in message (...) (21 years ago, 29-Apr-03, to lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) the length of the wire has nothing to do with the speed. the problem is that one motor, the first one on the line, is getting most of the power. the motor at 9v, 12v or 115v that doesn't mean thats the exact amount of power that it uses, it (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) I've thought of a simpler way of describing my system. Basically you have a rope stretched between two towers. If you pull the rope the span goes up, release it and the span goes down. The wire is connected to the lift span at both ends via (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) my description was not that good. here is how the diagonals are on my bridge: / | \ | \ | \ | \ | / | / | / | / | \ and the diagonals in the spreadsheet: / | \ | / | \ | / | \ | / | \ | / | \ (hope my ascii art turns out ok) so only 2 of the (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) I don't follow. It appears your diagonals go in both directions, mirrored about the center of the bridge: (URL) did you mean that your diagonals go from top right to bottom left (looking at the right-half of a span), and the diags on my (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) Ok, here's my idea for a solution for a vertically lifting bridge. All you need is one winch connected to one lifting line. You also need one control line(running off the same motor but geared down 2:1). The lifting line goes up the first (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) i'm using eudora to read and send to the news group. that is probably what my problem is. ¤º°`°º¤ø,¸¸,ø¤º°`°º¤...¤øø¤º°`°º¤ Bob Kojima ko@fial.com (URL) Incorporated Telecom Monitoring Solutions 4343 SW Corbett Ave Portland, OR 97201 (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) your spreadsheet is awesome. it worked great for calculating the length and heights. the only small problem was that the diagonal braces on my bridge all go in one direction, which your spreadsheet does not model. so your spreadsheet could (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) the rails on the lift span are not connected to the rest of the rails. there is a separate power connector run to the rails on the lift span. since the rails are not connected, there slopes on the sides to help keep the rails aligned when the (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) Thanks for the tip, I guess we'll cross that off our "to try" list! JohnG, GMLTC (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
Chain: been there done that, it wasn't a pretty sight... Lego chain is not strong enough for the weight and forces a lifting mechnism will put on it. I tried chain on my lift bridge before eventually moving on the string. I bought over $120 worth of (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
In lugnet.technic, Christopher Masi writes: <snip> (...) The GMLTC tried that on our previous layout. We had a motor mounted in the span, geared down to technic 8-tooth gears on each corner. The gears would engage this piece: (URL) (1x20 gear rack) (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) In my view one of the simpler ways is to shaft connect the two motors if you can... You can hide it if you have the sort of lift bridge that has an upper connection between the two towers. It may not always work though. (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
| |
| | Re: drawbridge
|
|
(...) That is a nice bridge, but I was chiming in to comment on syncronization... Has anyone tried using a single motor, and putting the motor in the span? I know it isn't prototypical, but if the motor was in the span, and the string/chain was (...) (21 years ago, 29-Apr-03, to lugnet.technic, lugnet.trains)
|
