kris_pwnz

hello.
Could someone help we with some tips and suggestions of the winch building? Yea, i saw some plans and images and didnt understand what is the solenoid for? Like what it does and where can i get it. Can i make wooden drum?

RRW_SOAR

Get a used car ignition motor and couple it's shaft to a drum.

Selenoid is relay switch. With this switch you can turn on hi-current devices with a low current circuit, i.e., if you try to switch on a winch motor, your switch must be a very big one, installed close to the motor (cable resistence stuff). Instead of that, you can use a relay switc;, the low current side activates magnetically the high current part. Like starting a car, the key switch a small current circuit which activates a high current switch (aka the selenoid) under the hood.

Sure, I have a couple of photos that a mexican guy sent me, showing a wood drum he made. I need to dig my home computer to find them, if you're interested I can e-mail them to you.

jbrandon

Before we even go down this road let’s take a look at what happens during a winch launch.

There is a lot of stress on anything associated with the launch, the plane, the winch, the line and the battery. You will first take up line tension using the foot peddle, then let go of your precious sailplane and hopefully it will fly straight up the line to a reasonable altitude, from there you can look for that elusive lift.

To do this you need a power source, the battery, some way to control it, the foot switch-solenoid, the drum to hold the line. The foot switch is only a switch you operate with your foot, it energizes (applies power) the solenoid which connects the battery to the starter motor (because the foot switch could not handle the current, as high as 300 amps) – when that happens the line is drawn in and hopefully the plane goes up!

The winch must be very strong and I have seen winches built from wood but never a drum. I have destroyed very well made drums launching large, heavy sailplanes. There are a number of commercial winches available and are well worth the money. But if you have access to a welder, some angle iron, a drum, solenoid, line and some time you can make your own. I recently built a new winch for my use and you can check it out [link=http://www.theshope.net/winch]here[/link]. It is not the definitive answer, but will loft your 2-11 pound sail plane without breaking the plane or your bank. My cost was about $500 (including the battery) in total with me doing all the work but the drum. The drum is one of the hardest things to find.

You ask about the solenoid, it is just an electrified switch. Many winches us a 12V Ford starter motor from about 1960 and the solenoid comes from the same model year also. There are many other combinations you can use, it’s all what you have available and the size of your checkbook. These parts can be purchased from your local auto parts store.

Good luck!

kris_pwnz

Wow, the winch you have made looks cool. I have a welder and i could use my friends lathe to make the drum. i had a car winch somewhere in my garage, perhaps i could remove the drum and use it. Its pretty strong but there is a gearwheel attached to it. my friend will get me the starter motor (it's not ford). I could buy a battery(not new) and charge it.
Thanx for advices. My mail [email protected]

LadyPhoenix

JrBrandon,
Your winch looks well-made. Thanks for posting the "visuals" for us to check out. I've got all the other parts, and they're ready for assembly. My problem is finding the spool or drum for the line. Any suggestions on where I might look for one of these?
Before I get buried under demands that I do a "google search", I did...and still haven't found a place to get only parts.
Any help offered will be appreciated.
LP

Ol Ken

Mark Gervais in Montreal sells winch kits and parts. I have used them and the work very well. The machining is very good and the parts are strong.

http://www.mgertech.com/COMET-WINCHES.htm

jbrandon

LadyPhoenix: My drum was made by an individual I met on another [link=http://www.rcgroups.com/forums/forumdisplay.php?f=95]message board[/link]. You can go there and do a search for “winch drum” and when you find this guy you can PM him and ask if he would be interested in making one for you. I am reluctant to give his name or login name to protect his privacy. His workmanship is second to none but he is a little pricy, but you can get one in a very short amount of time and not have to wait until the “next run”, and oh yes, you can get one now. One of the problems with this type of equipment is there is very little demand for it so making and stocking these special parts is extremely expensive for the maker.

The drum suggested by thermalbum looks great and is a very good price, especially if it is Canadian dollars, I’d go for one if they are available. I’d email and ask before getting my hopes up! Ben there, done that!

One of the things Tim and my drum maker did that the Comet maker does not appear to do is use 3/8” side plates turned down to 1/4" on the outside rim. This gives the greatest strength where it is needed with low rotating mass on the outside of the drum. Every drum I have destroyed has failed where the sides met the inner drum. The first drum was welded and we broke the weld, the second had very thin (1/16”) side plates and we warped them, pulled out the connecting hardware and finally folded one over. When all the line gets wrapped onto the drum and you are still pulling on the line hard there is a tremendous amount of pressure in that area. Please, this is not a slam to the Comet winch, it is only an observation of the differences between ideas and more than likely the 1/4" sides are more than adequate for most launching.

You did not specify what type of launching you will be doing. If you launch for fun flying and not competition or contest work you can use a little lighter duty equipment. I built to launch large, heavy cross country sailplanes so I need a relatively strong winch, not in power but structural strength. I used a 12V motor and a 12V battery. My winch is also suitable for contest work without the fear of destroying light built airplanes on launch. I don’t do zoom launches but these large planes do put quite a lot of stress on the drum.

Years ago I knew a guy that was an industrial arts teacher (Metal Shop) at a local high school and he was able to make several things for me. All he requested is that I supply all materials up front so he would not use any of the schools property.

[link=http://www.superskeg.com/]Tim McCann[/link] also makes a very nice drum but he is a busy man and does not always have them in stock. And he also states he does not sell individual parts, only kits and I think his site states he has no kits in stock. I did manage to get one of his turnarounds and am very impressed with his work.

Since the message I have completely rebuilt my [link=http://www.theshope.net/retriever/]winch [/link] to get it into two pieces, battery and winch, as my back just cannot handle the weight of the winch and the battery in one lift anymore. I copied Tim’s design and the winch is very compact and can be easily lifted with one hand. The gallery is for a retriever build but the last picture will give you an idea of the size compared to the D31 battery. I am currently building a cart to hold all the “stuff” needed so I can get it to the launch point in one trip.

PM me if you have any questions.

mgermca

Good day gentlemen.

Interesting thread.

With respect to spool construction we have found 1/4" 6061-T6 straight endplates to be entirely adequate for the job for which the Comets are designed - full pedal capable zoom launching at contest level of 3-3.5m molded composite sailpanes using 190 lb braided nylon winch line. About a dozen units in the field currently with no failures to date.

Wooden spools are possible, probably should be used for very light models whose launches will require only light line tension. I would recommend high quality plywood for the endplates and using strong and numerous fasteners to tie it all together (endplate to endplate) through the spool center, jbrandon is right, the pressures created by the cord wound onto the drum are enourmous and anyone who has flown sailplanes off of winches has at one time or another seen warped spool endplates.

Certainly the tapered thickness endplates are a bit stronger but trust me, they are a whole lot more work to make and are therefore not cheap.


regards!

Mark

LadyPhoenix

JRB & TmB,
Thanks for the prompt replies! Wow--I believe I've hit the RC Jackpot with this site!!
At the risk of sounding really cheap, I think I'm going to try building one out of wood, first. That way, if it works, I'll still have money left over for ice cream!!
Forgive my oversight in not mentioning what plane I'm interested in launching. It's a Great Planes "Spirit 100." So far, I've been pretty successful with the hi-start, rubber launcher. I heard about something new, and curiosity has gotten the better of me, I'm afraid!
Again, thanks for the ideas and the info. If my "woodie" doesn't work, I'll at least have a new direction to strike out in!
LadyPhoenix

jbrandon

No need to apologize for being cheap! I am too, that’s why I make my own stuff. You know, anyone can buy something but not many can make anything.

I also have a Spirit 100 for my mess around plane. No I am not being snobbish but I have just returned to the hobby and needed something to get into the air quickly and I refuse to buy RTF or even ARF planes. I prefer to build from scratch, not even kits, plans and a stack of wood and sometimes not even plans.

The intention of my winch is for cross country and the planes are large and heavy and you have to able to put them out and take them down very quickly. In fact I just figured out how to mount my winch on the 2” square trailer receiver so now all I have to do is run the turnaround out to launch.

Many years ago one of the clubs in Southern California I belonged to had 6 winches made from wood and they always worked just fine. The only problem I ever saw was if something came loose and not fixed immediately it would cause the wood in that area to get eaten away and then it was very hard to repair, usually a rebuild of the box. Many flyers would come out to the field for a contest and really get perturbed by the wooden box winches and would joke about the club members being old, and not able to “get with it”. But the driving force behind the club were older, retired, savvy guys but they always came through. None of the younger guys ever contributed much of anything but criticism, never ran for office, never stepped up and purchased winch line or even ice cream – and yes I was one of the younger guys then.

By trade I am a cabinet/furniture maker so wood is my medium but for durability I used metal for my winch and retriever. It also gave me the excuse to buy a welder and some other metal working tools I’ve always wanted but never could justify the expense! With metal you can build more compact and much stronger. But I do not believe you can get by with a wood drum. I’ve seen it tried and they will not hold up even with light duty. There is so much force on the side plates during launch that the wood will crack and break up and this could really be dangerous. In my last post I mentioned the 1/16” side plates that folded and that was not a pretty sight, we lost the airplane. The Comet drum really looks like a good deal to me, good price but I did not check to see it was Canadian dollars or US or if they are in stock and available for shipment. Like mgermca stated, the 1/4" sides are probably more than adequate for all but the fool heated.

Good luck and keep us posted on your progress. Pictures are always nice too.

whulbert

My friend has a home made winch and it does work but at todays prices I am going to drop $720 in the mail and get a little big winch and a wal mart battery. Warren

whulbert

My little big winch came in the mail today and it is a piece of art work. Get one. wo