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Rob

Gonna build another semi trailer:

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Some of you may remember the old trailer I'd acquired back in about 2010 or so. It's 42' long, single drop with hydraulic ramps on the back. All this works well and with the suspension, (Hutch 7700) adjusted as it should be, tracks perfectly straight behind a truck. Haven't seen another with my own eyes that pulls as straight really. I did cut the old neck off this trailer back in 2012 and replaced everything except the outer rails along with all new brakes and hardware. Trouble is the thing is originally from New Hampshire and is quite rusty wherever it can be although functionally it is fine.

Through the years I've been able to acquire everything needed, (suspension wise) on the inexpensive side, (staying with Hutch spring) through closeouts, dead stock, auctions, etc. to replace this trailer so going to build a new one very similar except three feet longer and 8'6" wide. I currently have 28' flat lower deck, 10' upper deck, and 4' dovetail to which the hydraulic actuated ramps attach. I'm going to lengthen the new trailer lower deck to 30', and the dovetail to 5' to lessen the "breakover" angle from the approach to the flat deck. The 10' front deck is fine as I don't run anything with a sliding 5th wheel nor plan to.  Both my B-67, and the B-61 pull this fine as do my R models. I don't really require tandem axles on the pulling units so moving to single drive air rides as I come across them so the neck length is adequate. The "breakover" mentioned is the transition from the dovetail to the flat of the trailer deck. It is still just a bit steep for automobiles but fine for trucks.

Haven't run across a set of axles yet but will probably purchase them new. Have spent a lot, and wasted a lot of time looking at rusty trailers past their service life and not too many out there in the 45' range any longer so going to build my own. Don't want a 48', or 53' trailer as too long to jockey around easily for me. Buddy at the heavy truck parts dealer I usually work with sells both Rockwell-American, and Pro-Par trailer axles. Really have no experience with either brand but both are offered in the 22.5k range I'm looking at.

Pictures will come along the way as the project starts later this spring.

 

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Remember we are like kids, and like to see pictures.   

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mehhhh. it can't be no worse than the 4 track train wreck between my ears!!   :o

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rob     what do you do with the r model wash wagon?

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Nuthin. It still looks just like the photo. Still use it from time to time filling swimming pools and water wells for cattle but that's about it. Likes to have some heat in the exhaust with 5300 gallons in the water tank.....

Does a great job blowing smoke rings under power along with darkening out the sun under full engine load as it runs very well.

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I had not considered air powered ramps at all. Your setup looks interesting for certain. Also looks as if they depend upon gravity to lay down? If you could send some detailed photos I'd really be interested in the concept. Just last week I rebuilt the hydraulic pump in my trailer and the ramps function just as they should. There was a solenoid cartridge that went bad and with that replaced all is fine again. Supposed to be nice today so I'll shoot a video of them operating.

I didn't realize there was a limit on total upload space so I've been going back and deleting older photos as they were not resized down and I ran out of space.

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I can certainly take some detailed photos for you. (when snow is gone and warms up a little:D)

It is a simple system. Your are right , gravity puts ramps down. As you can imagine , they can come down fast . I release air slowly so they don't come down to fast. 

 

 

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It would be easy to dampen the downward fall and thus slow their decent with either an air valve such as a flipper, or a couple of electric solenoid valves. You would need to wye the supply line in/out so one valve was open on the inflation cycle to raise the ramps, (other line blocked) and reverse on the decent. The air line which is open for the ramps to fold down would have a restriction orifice in the line to control decent rate. I'm assuming your raise rate is satisfactory or this could be worked with also. A restriction orifice in your existing line would do the same both ways and would probably impact the ramp raising rate.

I like pneumatic controls as well as hydraulic motion if the system is designed proper. Both have their advantages, and disadvantages.

I've got a bit of time in both systems.....  

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you could probably control the rate of decent by reducing down the exhaust port. use reducer fittings till you get down to a small enough size that they come down nice and easy. 

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I reinstalled my freshly rebuilt pump and hav

11 hours ago, Rob said:

I had not considered air powered ramps at all. Your setup looks interesting for certain. Also looks as if they depend upon gravity to lay down? If you could send some detailed photos I'd really be interested in the concept. Just last week I rebuilt the hydraulic pump in my trailer and the ramps function just as they should. There was a solenoid cartridge that went bad and with that replaced all is fine again. Supposed to be nice today so I'll shoot a video of them operating.

I didn't realize there was a limit on total upload space so I've been going back and deleting older photos as they were not resized down and I ran out of space.

Here is a quick video I shot this afternoon.

 

 

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I like the airbag  idea.     

Rob, how long of stroke cylinders are on your ramps.     Scrapper buddies get gradalls in to scrap pretty often, and they have 2 cylinders on the front axle to level the truck.        I think they are only 8" stroke, and prob not long enough though.   

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They are 24" stroke tie rod cylinders. Really nothing special and most any farm type store has the type. These are 3.5" bore.

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I thought they looked alot longer.   I can get the 8" for basically free, so I was hoping.  

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Thanks. These were less than $325.00 delivered for the pair as I caught them on sale at Bailey Hydraulics. I have hoses and fittings in the shop to make everything new.

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Here some pics for you Rob.

It's just a rectangle made from square tubing , sitting in a channel. Has 2 push rods (I will call them ) connected to the bottom of the ramps. 

I have the air spring # in the shop if you like . Its just a firestone air bag.  And if you would like some measurements, I can get them for you. 

I can't seem to download a video directly. If your really interested I can download something to youtube for you to see. 

5ae2426e15c1c_Image2.jpg.cd0b79386d9abcc25b3acac8e63879a7.jpg

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And I have to include a pic of my truck …………………Just because I like it so much.

5ae242bf20370_Image7.jpg.bd714e99a96997e3bc08c9b1246d0459.jpg

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If it wouldn't be too much trouble I'd like to see a video of the operation. It looks ruggedly mechanical but air bags output a lot of force so easy to envision it working. Best keep it greased as that's a lot of sliding action going on. The ramps ever bind on you? Doesn't look like there is much gap between their hinge pins and the rotating sleeve of the ramp(s). I assume both ramps go up or down at the same time?

That's a nice looking R model . I like the spokes. What's in it for drivetrain? I see it's an "Econodyne" series.

Rob

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Its no problem getting some video for you Rob.  I will get it for you later today. 

You mentioned the small gap between the hinge pins and the rotating sleeves. When I got the trailer the ramps didn't work very well.

The hinge pins were sloppy and things would just bind up .  I find the less play there is , the more energy goes to raising the ramps . 

I've never had any trouble since i tightened things up. 

To your point of greasing the slide. I actually don't grease it . You will notice no deck boards above it. That way I can wash it regularly. The grease just attracts a lot of dust and crap.  

For the video I put a bit of lubricant on it. So you can see how easily it can move. With no lubricant you need to give it a little help. (equivalent to lifting 20 or 30 pounds). The reason I like to" help"it ,  you will see that when the ramps go up . They go fast. If someone was close to them, they could easily get hurt . It actually works really good because the ramps come off the ground. I clean all the dirt off the ramps , then give them a bit of help , then they stand up nicely. 

My R688st has a 350 4V with an 8LL trans and 4:42 rears . I'm the second owner. Its the original paint on it. 

      

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1 hour ago, 85snowdog said:

Its no problem getting some video for you Rob.  I will get it for you later today. 

You mentioned the small gap between the hinge pins and the rotating sleeves. When I got the trailer the ramps didn't work very well.

The hinge pins were sloppy and things would just bind up .  I find the less play there is , the more energy goes to raising the ramps . 

I've never had any trouble since i tightened things up. 

To your point of greasing the slide. I actually don't grease it . You will notice no deck boards above it. That way I can wash it regularly. The grease just attracts a lot of dust and crap.  

For the video I put a bit of lubricant on it. So you can see how easily it can move. With no lubricant you need to give it a little help. (equivalent to lifting 20 or 30 pounds). The reason I like to" help"it ,  you will see that when the ramps go up . They go fast. If someone was close to them, they could easily get hurt . It actually works really good because the ramps come off the ground. I clean all the dirt off the ramps , then give them a bit of help , then they stand up nicely. 

My R688st has a 350 4V with an 8LL trans and 4:42 rears . I'm the second owner. Its the original paint on it. 

      

Seen a lot of trailers where the ramps were set up like that with grease zerks that didn't get attention. Eventually the grease goes away, the shafts wear, and things bind. Surprised the weldment the airbag bears against doesn't have either nylon slide pads or grease to lessen the friction. However your ramps are not that long so the effort required would be less than I was originally thinking.

I was wondering about the speed at which they actuated. All kinds of ways to control that as mentioned earlier. The hydraulic ramps on mine are very linear in operation and consistently operate as my short video showed.

Been thinking more and more as I clean on the shop, (which is dangerous in itself) and my trailer needs extended three feet so thinking that's what I'm going to do rather than replace it. It's served me well and all bearings, brakes, two drums, air lines etc. are new last fall so may as well extend it's tenure of service.

My ramp hinge pins are a piece of schedule 120 pipe welded solid and the ramps part are schedule 80 pipe. There was about a 1/8" gap between the two, but that has worn larger over time from the friction of the ramps rotating through their arc during deployment and raising. Several years of use has taken it's toll and they rattle terrible going down the road from the clearances.  

Appreciate your help and time.

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49 minutes ago, 85snowdog said:

 my problem is I have too many projects , and too little time .

 

Sorry but I find that very hard to believe.....  (As I look in the mirror too)

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Thanks for taking the time to make and upload the video. They do operate quickly and my luck would have something destroyed on short order. Pretty simple design staying with a single cantilever style. I'd have to restrict the free flow air but my level of comfort isn't there as yours would be having experience.

I was out to the shop starting to measure mine up and make a material list today. Got the ramps and back five feet of the trailer figured out and rough designed. Going to have a 40' flat and 5' beaver tail plus the ramps. My main beams are looking to be weakening and many of the xmembers are rotting under the boards down the center of the trailer. Looks like I'd be  better just building a new one and scrapping this frame as I'll reuse the axles and springs. I have all new hangers and hardware for the suspension.

I liked that blue R model in the background. Looks like you folks have a pretty good interest in old Mack Trucks too.

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