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[ISMrider]

Some Photos

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[kevin thomas]

ISMrider, on Jul 31 2004, 01:51 PM, said:

Some Photos
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[kevin thomas]

kevin thomas, on Jul 31 2004, 07:41 PM, said:

ISMrider, on Jul 31 2004, 01:51 PM, said:

Some Photos
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I just posted some photos of my first back yard rope tow above, still figuring out how this posting thing works. I plan to build a much longer to this winter (850 feet) verses the 120 foot tow that you see in the pic in the prevous post. Kevin

[kevin thomas]

[quote name='kevin thomas' date='Jul 31 2004, 07:46 PM']
[quote name='kevin thomas' date='Jul 31 2004, 07:41 PM'][quote name='ISMrider' date='Jul 31 2004, 01:51 PM']Some Photos
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I built the above rope tow for less than $150, the rope was more than half the cost it's 5/8 inch. I still don't understand how to do a long braid splice. Is it very difficult??? I ended up using electrical tape to hold a messy splice together. Any help would be appreciated. It had to retaped every day or so! The 120 foot tow runs at 300 feet per min and has a 10 foot vereticle.

[SkiBachelor]

Hey Kevin, welcome to the forum.

I wonder if this page can help you out with your splice?

http://skilifts.org/...pliceimages.htm

[ISMrider]

Kevin what did you use for a motor?

[crazyskier91]

I have been working on designing a ropetow (As soon as I get a place to put it), The system I used was a floating bullwheel attached to the counterweight at the bottom, with a motor coupled to a sort of table. Pictures the legs with beams connecting each of the four legs, put the motor on one side of it with the shaft running though your bullwheel and the same shaft held down on the other side with some sort of semi circle thing welded on. Basic and simple, I am building a mini version, out of K'Nex, which happens to be my onl building material. I was thinking of using either a 10 HP electric motor, or the 40 HP outboard from our old boat, that would be one ---- of a ride!

[kevin thomas]

[quote name='crazyskier91' date='Jul 31 2004, 09:23 PM']
I used a 1/3 HP 120 v electric motor that I got for 20 bucks! It could tow 2 kids at a time or one 180 pound adult, much more and it would slow down especially if the snow was sticky. I also has trouble with ice building up on the gripping pullies causing the rope to derail. I had to stop the to every 15 minutes or so to scrape the ice off with a screw driver, unless the snow was very dry then I didn't have the problem. I can probably figure some sort of pully scraper design next winter.

Kevin

[liftmech]

Alexvb222000, on Jul 31 2004, 10:07 AM, said:

No,

I'm talking about runing the wire for a 15 hp motor (electric).
I live about 1000' from the top of the slope (I actually live right next to the top so its a 1000' across to the top not up) I know that a wire just for that will be $$$ but then theres the lighting wire (maybe) and the snow guns wiring and that runs off of a 50 Amp 230 volt circuit alone. Also I need to power a pump that I have. So its a little more then just 1 wire (although I do want to run a main power supply cable out there and just have a 200 amp @ 230 volt box, and a 200 amp @ 115-120 volt box.)

I really have not even considered a safty wire yet.  Won't I have to run like a 230 @ (whatever the amprage of the 15 hp motor would be) wire across in order for someone to knock out the wire and shut off the motor?  How does this work? Like a shut off switch?

Thanks,
Alex
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Your 230 VAC power supply will be the most expensive to run. Power for the motor can be run on Romex wire, probably 12 to 14 gauge three-wire buried in conduit. Your safety circuit will be 12 volts DC, i.e. a car battery- it's much safer that way. You don't have to use a battery; you can hook up a battery charger to your 110 supply and run your controls from that.
I've got your electrical diagram mostly finished and it will be in your inbox soon.

[kevin thomas]

liftmech, on Jul 31 2004, 11:36 PM, said:

Alexvb222000, on Jul 31 2004, 10:07 AM, said:

No,

you really don't want to run electric for 1000 feet, that get very expenive, and you can run into safty issues and not sure if there are inspection requirement for that type of wiring.  Here in PA we had to run 600' of electric to our small shack at my business.  It cost over $2,000 to install and inspect!  Are the neighbors so close that a gas engine in the winter when their indows are closed would be a bother to them?  Have you asked their opinion?  Maybe they wouldn't mind.

Kevin




I'm talking about runing the wire for a 15 hp motor (electric).
I live about 1000' from the top of the slope (I actually live right next to the top so

Thanks,
Alex
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Your 230 VAC power supply will be the most expensive to run. Power for the motor can be run on Romex wire, probably 12 to 14 gauge three-wire buried in conduit. Your safety circuit will be 12 volts DC, i.e. a car battery- it's much safer that way. You don't have to use a battery; you can hook up a battery charger to your 110 supply and run your controls from that.
I've got your electrical diagram mostly finished and it will be in your inbox soon.
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[liftmech]

[quote name='kevin thomas' date='Jul 31 2004, 06:39 PM']
[quote name='crazyskier91' date='Jul 31 2004, 09:23 PM']
... I also has trouble with ice building up on the gripping pullies causing the rope to derail. I had to stop the to every 15 minutes or so to scrape the ice off with a screw driver, unless the snow was very dry then I didn't have the problem. I can probably figure some sort of pully scraper design next winter.

Kevin
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Cut a piece of 1/4" steel plate to the shape of the pulley groove and mount it so that it just misses rubbing on the pulley. That should scrape out ice and snow. We don't need them in Colorado, but in Washington we used them on rope tow pulleys and chairlift bullwheels alike.

[iceberg210]

Look at Granger or at Northern Tool and Hydralic for gear boxes cable etc.

[liftmech]

Grainger is a great place for that, and they'd also have a lot of your electrical needs. Good call, Erik.

[Alexvb222000]

ok,

I'm haveing trouble finding all the things that I need for this tow. I need a little help on finding a way to run a three phase 15 hp motor off of Single phase power (a cheap way). I know that a lot of resorts use a VFD (found out about it on eng-tips.com) ~I also have no clue how to find one of theses things or what VFD even stands for~. A lot of reasons they use them are becase the enable a SOFT start to the tow, Revearse (incase someone gets caught in the lift ~not good!~), and it enables a variable speed control.

I talked with a guy that has done mutiple rope tows (electrical engineer) and he said that this was the best route to take and that I would need at least a 30 hp VFD to run a 3 phase motor.

Now I couls do all this, But since I have not spent a dime on the motor portion yet I could also look for a Single Phase 15 hp motor (which are extreamly rare I guess because I can not find one at all).

So If you can help, of course, PLEASE DO SO.

Thanks,
Alex

[crazyskier91]

I would recoomend you use a phase converter. Check E-Bay, a guy was selling one. I think that would just mean the motor starts and stops.

[Bill]

Yeah to go from single to three you would need a phase converter. Have you looked into how much power the thing will consume and how much it will cost to operate it?

[Alexvb222000]

Well the cost to operate it is not an issue to me (only about $2.00 an hour I think, If that). And I think that they (meaning over all) only use about 60-100 amps @ 230 volt at the most. I Don't know for sure because I don't have a motor picked out yet.

And I'll look up the converters but I think that they are as expensive as the motor it's self!

The cheapest one I found was a Baldor, it is $719 (new), But it was a 10hp. Its seems as though I may need to go a little lower for the Hp because of cost. (can't find one for less then $1200) That is also because I was looking for new motors.

A 3 phase motor is actually cheaper then a Single phase motor! There are less moveing parts in a 3 phase from what I read. Although there cheaper, its only by a few hundred dollers and the cost of buying a converter off-sets the "cheapness".

[liftmech]

3-phase motors are also smoother overall because there is less time between the 'peaks' of the AC sine wave than with only one phase. VFDs are great for ski lifts, but their cost makes them attractive only as part of a multimillion dollar installation like a chairlift.

[Patrick Sullivan]

I always had a fantasy of using an old snowmobile...keep the sled's drive system and regear the dropcase and detune the clutch. Plenty of power. a 340 should do the trick...about only 20-30 hp there. No gearshifting to worry about like most of the ones made of old Fords & chevys...as for a safety system just run an ext. cord across 2 wood posts and have it grounded right to the stator plate ground which will kill the motor. and just have a kill switch or the traditional Big Red Button to kill it. As far as energy, a Polaris 340 I know for a fact can run for a day and a half at 1/2 throttle fed by a 7.6 gallon tank. No need to worry about 50:1 mixed gas either...most sleds made after 1978 were oil injected. And if you want it quieter just stuff some ceramic muffler pack in the silencer end of the pipe.

But if you have the money to buy & run what will most likely be a 220v 3 phase motor, then go for it. I'd look at a Granger catalog in the HVAC section. Some of the motors for the 20 ton units might be big enough..but if it was me I'd go gasoline...or diesel....Briggs & Stratton makes diesel/kerosene powered motors.

[Patrick Sullivan]

I'd also keep the fuel tank outside the back of the shed. If you can find a liquid cooled motor all the more better, get the heat exchangers that go to the motor, and mount those outside in boxes covered with snow. It could run forever like that.

Like I said the centrifugal clutch on the motor (Primary) and the centripital clutch(secondary) are a good thing to have. If you take it to a snowmobile repair shop or a dealer, tell them to have it calibrated for as much torque as possible.

As far as throttle control, modify a gear selector off of a mountain bike for speed control. At idle the rope won't move unless you have it clutched that way.