View Full Version : Gate assist - help

11-15-2004, 10:51 PM

As you can see my trailer has high sides. I've already done a search for pictures of a gate lift system but can only find them fore trailers with low sides. Anyone know of pictures of a gate lift system for a trailer like mine.

I could probably build my own system but don't know what the gate weighs - reckon I could weigh it in the down position with a bathroom scale?


kickin sum grass
11-15-2004, 10:54 PM
look at a trailer place. Some will have a large spring you put on the rod that goes thru the hinge. They don't work as good but better than nothing.
If I can find a pic I will post it.

11-15-2004, 10:58 PM
You could mount the lift system on the outside of the sides by welding in to the upright supports. Garage door springs work great inside of square tubing plus they come with the cables already attached. Use the "heaviest" springs you can find. Inside 2" square tubing a #160 spring will fit. With a full gate you will want to build two of the devices which can be done for less than $100.

PM me with an email address I can shoot a pic of my assist.

kickin sum grass
11-15-2004, 11:07 PM
Heres a drawing hope it makes sense.
When you let the gate down it winds it up and then unwinds as your are lifting up. Kinda like the springs that are used on a lot of discharge chutes but in larger scale.

11-16-2004, 03:13 AM
I think Jim's idea is the best, it's simple. But, here is what I was thinking....Now mind you, the top will not stick up that far, as a matter of fact, it will hardly be noticable. The same thing with the size of the pulleys - they will be small, and not stick out like it looks on this rather "crude" drawing. Run the cable over the top of the first pulley, down the back to the inside of the lower pulley, then out to the end of the gate (further than what the drawing depicts). This will give it more leverage to pull with. Actually, it would look rather neat and tidy done this way. The pulleys are held with C channel of square tubing. Or, you could fabricate your own brackets like I do for all the ones I build.
The one thing with Jim's design, is that you would run in to alignment issues at the back of the trailer - from the tube to the gate. You would have to run a long eyebolt out the SIDE of the gate, rather than the top, and it would have to stick out long enough so the cable wouldn't rub the back corner of your side.

11-16-2004, 06:42 AM
Runner may lack in his drawing abilities....lol, but his idea is great. That is pretty much the same as mine (with low rails) omitting the bottom pulley. You might even be able to omit that bottom pulley, but then the cable would be hanging out. I like Joe's idea better, with the bottom pulley. Other than the steel, you should be able to get most items at your local hardware store. Another, less popular route would be to use leaf springs. I have seen a few with these mounted underneath the trailer, upside down. I really like this idea because for one, it's out of sight and out of the way. Two, should it break I doubt that it would or could injury anybody.

Now that I think about Joe's drawing, I am not sure if that will work. I think with that second pulley down so low and the eyebolt mounted so high on the gate (in the vertical position) that bottom pulley would just act as a pivit point in which the spring would not extend out (when the gate was down) and not retract (when the gate went vertical). Does that make any sense? I am not sure the sping would stretch. Now, if the bottom pulley was closer to the top, closer to the eyebolt that is attatched gate when the gate is vertical, that would give good stretch to the spring. Then on the other hand, if it was that high up, why even have it there? One thing that I don't like to see is that much cable exposed. If it ever decided to break, that is a lot of cable to be "slung".

Personally, knowing it might be more work, I would go with the leaf spring idea that I mentioned earlier.

Let us know what you come up with. Also, please share some pics.

11-16-2004, 10:57 PM
You are certainly right about the possibility of that just pivoting. We would have to make sure that the bottom pulley is just high enough. I drew this based on the approx. height of a top rail if there was one. On the regular type lift, it does the same thing. When the gate first strts to come down, there is not alot of cable actually pulled. The way for us to know if it will function geometrically, would be to hark a place i=on the trailer wher we would have our bottom pulley. Then, while lowering the gate, hold a tape measure to a spot near the end of the gate. However much tape comes out during the arc, will tell us how much spring will be pulled. Not a whole lot of spring needs to be pulled, as we can alway start with some tension on it. This adjustment is made when we hook up the cable U-bolt clamps.

11-16-2004, 11:57 PM
Hey tx-angler, I have a trailer like yours - only with 24 high sides. I'm not an engineer but something I've been thinking of doing is to make use of a vehicle's shock absorber. It's cheap enough. I just need a friend or somebody with a welding machine to help me make it work.
I would like to hear some input on this from the guys with the engineerical skills whether this will work or not.
Here's a drawing of how I invision it. It's installed on the back of the trailer. The one end of the shock is attached to a bracket welded to the frame and the other end to the gate. I think it's a lot simpler in design - and cheaper - than to rig pulleys, cables and springs?

11-17-2004, 12:09 AM
Raise your tailgate all the way up. Extend a line across the top of your fender back to the tailgate and make a mark there. Weld a piece of 2x2 tubing on the side of the tailgate, horizontal and even with that mark. You might have to extend the side of your tailgate out some.

The length of that tubing will be determined by putting the tailgate down, and again sighting across the top of the fender. That point will be the top of the tubing.

Next get two strong garage door springs, secure them in tandem and put a piece of plastic PCV pipe around them. Lay them across the top of your fender, secure the front with a strong eye bolt and tie the back of the spring assembly to the tubing on your tailgate. Adjust the stretch of the springs to match the weight of your tailgate.

I have mine on the curb side. It is simple, strong and very effective. By the way, this was Eric Elm's idea from his website, and for the past 5 years I have been thankful to him for it.

11-17-2004, 10:04 AM
I just took some pics of my assist. The enclosure is made of 2" square tubing and a 160 lb. garage door spring.

11-17-2004, 10:06 AM
Here is the pulley system. I just recently re-did this. The one before was just...the actual pulleys were brass and wore out quickly. A little rusty, but will see paint soon. You can see the u-bolts there....that spring is extended all the way. The brackets are made of a piece of the square tubing with one side cut out to make a c-channel. Since the pulleys were a little bigger than I wanted, I had to add material to the "c-channel". I just welded them together.

11-17-2004, 10:10 AM
And the last one. I took the eye-bolt and cut it so that it's not closed off all the way. This way I can pull on the cable and take it off my gate in the case I need to make adjustments to the u-bolt to add or lessen the tension.

11-17-2004, 10:11 AM
i dont have a assist. but couldnt you throw it on the inside of your trailer around where it usually goes only sideways instead. If it lines up with the mesh part you could fab a sideways support or a bolt with some washers. By the looks of them it would only sit a couple of inches inside the trailer.

11-17-2004, 10:16 AM
i dont have a assist. but couldnt you throw it on the inside of your trailer around where it usually goes only sideways instead. If it lines up with the mesh part you could fab a sideways support or a bolt with some washers. By the looks of them it would only sit a couple of inches inside the trailer.
You could, but you run the possibilty of bumping it with equipment....I would have given up 4" of the inside of my trailer. That's a big "con" and don't really see any "pros" in doing it that way.

scott's turf
11-17-2004, 11:27 AM
The larger the angle, where the cable meets the gate in the down position, the less force required to lift the gate. The draw back with this is that the springs may not have enough stretch. This is why on gagage door they use additional pulleys to cut the distance in half that the spring will travel or they use a tosion spring that is also used on most enclosed trailers. I personally don't know what is meant by a 160# spring. Is that the max load? Spring force is usually given as a constant such as 75 lbs/in.

pncservices, there are problems with that design. You are essentially using the air spring as a comression spring. Besides having a mounting point sticking out past the end of the trailer the design also restricts enough movement to even get the gate horizontal.

11-17-2004, 03:34 PM
Not to rain on your pasade, but I don't think the idea is going to work for the same purpose. First, the design is somewhat flawed, because according to the drawing, the bracket that sticks out of the back of the trailer would only allow the gate to drop to the point that the shock absorber would bottom out. The bracket and lower end of the shock absorber would have to be lowered. But what;s further than that, is the concept of how a shock absorber works. This would work great for keeping the gate from slamming down onto the ground, but it would give virtually no lifting power. That is When a shock absorber is compressed, it then releases. What it doesn't release, gives very little push resistance. Until it is stretched back out again, it has no push resistance power (unless compressed to an even lower amount). afterall, which is what you want. I hope this helps. Walker Talker's pic shows the most proficient and safe setup for this. Mine is the same way. Mine has PVC pipe for my encasement, however I do not recommend this. All that I have built after mine were done with 3" exhaust tubing. Steel is the only way to go. I have always meant to change mine, and never have. I really need to, though.
By the way, I love those fenders. Now, did you make your own bracket for your two cable-guide pulleys for the back of the trailer?

Gautreaux's LNG
11-17-2004, 03:40 PM
Trimmertrap makes a spring assist that may bolt to your trailer. Check it out. Saw one at GIE.

11-17-2004, 04:47 PM
The one that Trimmertrap makes is just crazy. I can't even believe they are marketing such a piece of junk. This thing is a joke, as it is nothing but an accident waiting to happen. I don't think I've ever seen anything quite so dangerous that was actually marketed in our industry.

11-17-2004, 06:10 PM
how about sticking on the outside of the trailer where it normally would go and stick a eye bolt going out to the side like the picture up a few posts. If you have something in the way you can add a pulley at the end of your trailer.

John Gamba
11-17-2004, 07:30 PM
Heres a drawing hope it makes sense.
When you let the gate down it winds it up and then unwinds as your are lifting up. Kinda like the springs that are used on a lot of discharge chutes but in larger scale.

This is what i had on a high sided trailer like yours. It works best half way up to close. It did help alot and was easy to do.


11-17-2004, 07:38 PM
I saw a trailer at an expo that had this, and I think that this is the best setup yet. The one there lifted real easy all the way up, though. My question would be How would you ever **** the spring enough to put tension on it before the gate is installed. When the gate is installed, it is installed in the "up" position, so the spring is most laxed. But to even put just a LITTLE tension on this spring takes a great deal of torsion force. There must be a tool or something they use for these type of springs for doors and such. For instance, the ramp doors on enclosed trailers use this type of spring on the cable spool.

all ferris
11-17-2004, 08:05 PM
I did about the same thing as walker talker only different. I have my springs in 10 feet of gavanized pipe that is closed off at both ends with a washer so if the spring or cable breaks it won't shoot out of the tube. I tried the same thing as walker talker but found that it didn't have enough pull so where walker talker has an eye bolt on his tailgate I have an additional pully. I also used 2 springs connected end to end in the pipe then the cable goes from the spring to the pully on the gate and back to the spring housing where it is bolted down. This doubles the lifting force doing it this way rather than just having the cable going from the spring to the gate. I have had this for 3 years now and have only broken the cable once (LOOK OUT!).

11-17-2004, 09:07 PM
I don't have a way to take a picture of it but my trailer has one of the best systems I have ever seen for raising the gates. I have a two piece gate and in the middle of each gate down at the bottom is a leaf spring assembly that extends about two feet back under the trailer. When you pull the pin to let the gate down it will fall about half way down and then you can step on it to press it down to the ground. When raising the gate the leaf spring works so well that I can take my foot and pull up on the side of the gate and it easily raises up to the point that I can grab it with my hand and pin it closed. A local company that builds them uses this method and it works great. Makes people think that you have strong legs but it takes very little effort and you never have to worry about cables breaking.

11-18-2004, 02:59 AM
Now, did you make your own bracket for your two cable-guide pulleys for the back of the trailer?Yes, I took a piece of the square tubing and cut one side off....to make a c-channel. I had some flat metal around and welded it to the sides. I didn't anticipate this, but had to do it because the center of the top pulley set too high. The pulley's are meant for a window that I found at the hardware store. All-in-all, I think I have around $60 in both my assists.

Carolina Cutter
11-18-2004, 03:02 AM
Do you guys still pin your gates with this system??

11-18-2004, 03:34 AM
This is sort of how I did mine, too. I just used all flat stock and built a rectangular frame with it. I then drilled the holes for the pins and used pulleys from a block&tackle setup I bout from Home Depot (about 5 bucks, I think). The reason I used these things for the pulleys was that the oulleys are one piece, unlike those for garage door hardware that are split. I didn't want it wearing and splitting eventually. I'll try to get some pics on here of it.

Yes, you still have to pin the gate. It doesn't hold it shut. I mean it does to a degree, but a little push and the gate falls right down. It IS nice being able to lift your gate with one finger, though. Although, I just use my big toe under the end of the gate, lift my foot a bit, and the gate comes right up to me. You get spoiled with it after awhile.