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Pages: 1 | 2 | 3 | (show all) Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Dump trailer       02/25/06 02:45 PM Attachment Edit   Reply   I sold my old dump truck because I can't justify the expense of tag and insurance for no more than I use it, and it was awfully slow on the road. Since I need a dump often I thought I would build me a dump trailer. It seems like there is a lot of interest in dump trailers so I thought I would build it on this website as well as in my shop. I went yesterday and bought the steel. I got 6-20' sticks of 5" channel, 2-20' sticks of 2X2X1/4" angle - 4X8'X11gaflat metal, and 1 piece of 1/2"X4"X4" flat bar. Total cost was 642.00 I went on Wed. and bought the pump/valve/resivoir/motor, hitch and tongue jack. The cost for those was 497.00 I started this morning cutting the steel to length. The trailer will be 6' X 12' Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       02/25/06 02:47 PM Attachment Edit   Reply   Here I have the sub frame welded together sitting on the bucks It is just a 6' X 12' rectangle butt welded together Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       02/25/06 02:51 PM Attachment Edit   Reply   I always make an A-frame tongue because it stops the frame from racking. The tongue is made of 5" channel the same as the frame. Here is the tongue with the hitch and jack mounted Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       02/25/06 02:56 PM Attachment Edit   Reply   In this pic it shows how far the A-frame goes back under the front of the subframe, and how I terminate the A-frame. I also have the main frame welded together sitting on top of the subframe as it will be when it is finished. the main frame sticks back 1' behind the subframe Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       02/25/06 03:12 PM Attachment Edit   Reply   Here is a shot of the Pump. I got it at Northern, it's a 1800 psi, 1.6 gallon per minute pump with a 20' cord set. It will be power up, and gravity down. The cyl is a 4" 2 stage cyl that I have had for years. The first stage has a 24 " stroke, and the second stage is a 3" stroke with 28" of travel. I'm not sure why the 2 stages don't travel the same distance, but it realy doesn't matter to me anyway. I could have gotten a 4" X 24" cyl from Northern for 109.00, but the store closest to me doesn't stock it so I would have had to have them order it and no telling how long that would have taken. A 4"x 24" cyl would work good, but the 2 stage will give a steeper dump angle so that can't hurt, and like I said I already had it. Here is a pic of the pump and cyl Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       02/25/06 03:15 PM Edit   Reply   I'll keep you posted as I get more done, but that isn't bad for 5 hours work. Later, Nat Post Extras:       Pat Veteran Member Reged: 09/15/02 Posts: 4889 Loc: SouthCentral Oklahoma Re: Dump trailer [re: Nat]       02/25/06 11:22 PM Edit   Reply   Nat, I'll be looking forward to see this project develop. I thought I bought a dump truck. I agreed to the guy's price and told him I'd take it at his earliest convenience and then... So I guess I may be back to my thoughts of making a removable dump attachment to go on my 12,000 lb rated util trailer. It is dual axle with 4 wheel brakes. I was thinking of a side dump with a couple fold down jacks to support the side where you dump so as to not have all the load on the one side and stress the bearings, wheels, and tires. One friend suggested a belly dump but I don't think there is enough clearance to avoid putting too much stuff in the way of moving out with the trailer. Pat "I'm not from your planet, monkey boy!" Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       02/26/06 05:50 AM Edit   Reply   That looks pretty good, Nat. I have actually considered building a dump trailer a number of times. For small jobs, a six-foot wide trailer like that would be perfect. I could put a "wet kit" on my pickup pretty easy since both the main transmission and the transfer case have PTO doors on them. At one time I even thought about making a goose-neck dump trailer so I could completely jacknife it into small spaces with loads of sand and gravel. CJDave Post Extras:       kerosenedrvr New Member Reged: 12/04/05 Posts: 20 Re: Dump trailer [re: CJDave]       02/28/06 10:03 PM Edit   Reply   Nat, please continue to update your progress, and continue to include pics. I am very interested in your trailer but lack metal experience. A set of drawings would be great also. Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       03/01/06 06:13 PM Attachment Edit   Reply   I worked on the trailer today and have the cyl mounted. There will be a lot of stress when the cyl extends so I made a truss on the bed side of the cyl. I will also do something similar on the anchor end. This fuzzy pic shows the cyl in place. The anchor end is 11" lower than the live end. I'm no engineer and don't know how to figure the lift capacity, but just guessing from a bunch of years of this sort of stuff, I'm sure the lift will excede the trailer limit of 10,000 lbs. Later, Nat Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       03/01/06 06:23 PM Attachment Edit   Reply   I have the hinge done for the dump. The 5" channel subframe web isn't strong enough for the hinge so I had to put a sleeve in it. I have a piece of 1/2 x 4 plate that goes from the top of the mainframe extending down to the bottom of the subframe. I cut a hole in the 5" channel and capped the open side with a piece of 4'' X 4 1/2" X 3/8" plate and welded a piece of 2" ID DOM tube from the channel to the flat plate. I was going to use 1 1/4 shaft for the hinge pin, but decided to use some 2" that I had laying around. The 2" shaft wasn't long enough to extend thru and drill for a cotter key, so I welded a cap on one end and drilled and tapped a hole in the end and will bolt a piece of flat bar to keep the pin in place. It's hard to discribe what I'm talking about, but maybe this pic will Help. Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       03/01/06 06:26 PM Edit   Reply   I'm not5 used to this stuff and my shoulders are killing me so I'm going to do something different tomorrow. My axles and tires won't be in till Mom, anyway so it won't hold me up Post Extras:       GaryM Veteran Member Reged: 09/12/02 Posts: 1210 Loc: Warrenton, MO Re: Dump trailer [re: Nat]       03/02/06 08:37 AM Edit   Reply   Looking very nice Nat. Sounds as though your engineering it as you go along. I guess you have enough experience to do that. I know that I don't. Are the body sides going to be steel, or perhaps wood? Gary ---------------------------------------------- Hey! Aren't you supposed to be working? Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: GaryM]       03/03/06 06:37 PM Edit   Reply   Gary, it's simple: Bore Squared X .7854 X PSI X ELA=Torque. Load weight X ELA = Torque. If the first product is greater than the second, the trailer will dump. If not, then oh well. (ELA is effective lever arm) CJDave Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: CJDave]       03/04/06 06:44 AM Edit   Reply   CJDave, Help me out here a little. I always use the radius squared times pi times pressure per square in to give me the pounds of push. In my case with the 4" diameter of the first stage I'll have 20096 pounds of push, but I don't know how that relates to how much it will dump. The anchor end is 8'9" from the trailer hinge the "live end" is 6' from the hinge end and the anchor end is 11" lower than the "live end". What is the ELA, and where does the .7854 come in. Sounds like you know what you are talking about so it may be something I need to know in the future, Later, Nat Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       03/04/06 11:02 AM Edit   Reply   A guy on TBN sent me a link to this website http://www.baumhydraulics.com/cyl_calc_ang.htm From it it looks like I'll have 6877 lbs of lift at the "live end" of the cyl. That is about 6 ft from the hinge so should be more than I'll ever need. It is a neat site that may come in handy for someone Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       03/04/06 09:19 PM Edit   Reply   The ratio between the area of a square and the area of the inscribed circle is .7854. A Circle is .7854 of the same size square. So if you have a 4 X 4 post and throw it in a lathe and turn it into a round shape, the new area of the end of that post is 16 X .7854. What you need to know Nat is HOW HIGH above the pivot pin the live end cylinder trunion is. If you draw a line through the trunion pins of the cylinder, and then drop down and draw a parallel line which goes through the pivot pin of the dump bed, the distance between those parallel lines is the Effective Lever Arm that the cylinder has to work with when the dump is at the bottom. Then figure the load in pounds and the average distance from the pivot pin that the center of load is, and that distance is the Effective lever Arm of the load. So Load (pounds) times Effective lever Arm(inches), equals Torque Required. Then cylinder PSI times Area times Effective Lever Arm is the torque available. Hopefully the "available" is greater than the "required". CJDave Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: CJDave]       03/06/06 11:25 AM Edit   Reply   CJDave, I did the calculations you suggested and I come up with some weird numbers. I have 20106 as the (sq of the cyl X the psi ). From the live end of the cyl pin down to the hinge pin of the bed is 10", so 10 X 20106 =201060. The expected load is 6000 lbs so 6000 x 10 =60000. since 60000 is less than 201060 it will work. So if I subtract 60000 from 201060 and then devide by 11 I get 12823. Is that how much it should dump? Thanks, Nat Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       03/06/06 03:30 PM Edit   Reply   Well, it's do-over time. I gave it a dry run today, by hooking up the hyd. hose and running jumper cables from my truck. My cyl. is to big. I run out of the 2 1/2 gal resavior before it is half way up. I had just measured the ram on my 2 stage cyl, and it was 4". That was fine , except the piston is actually 5". So I don't have enough volume of fluid to use that big of a cyl. It is cheaper to get another cyl, so I ordered it from Northern today. I'll also have to re do the mounts because the cyl I have has a welded end and the cyl. I'm getting is clevis mount. Not a big problem, but stil would rather it worked right the first time., Later, Nat Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       03/07/06 03:11 AM Edit   Reply   Actually, the Effective lever Arm for the load may be more than 10". Remember that you use the center of load times the distance that the center point of the load is from the bed hinge pin. What was the "divide by eleven".....I didn't get that step. Also, be sure that when you measure the height of the cylinder live trunion above the bed hinge that the two lines are parallel to each other, not level with the earth. The one line goes through both cylinder pins and that gives you the starting point, then the lower line is parallel to that. CJDave Post Extras:       stumpfield Member Reged: 12/27/05 Posts: 31 Loc: usa Re: Dump trailer [re: Nat]       03/07/06 09:17 AM Edit   Reply   What type of welder is best for a novice welder wanting to building a trailer. I'm curious what welder (brand/model) do you use in this project? I want to get a welder. My 1st project will be building a trailer. Thanks. Post Extras:       egon Veteran Member Reged: 09/12/02 Posts: 3011 Loc: Nova Scotia,Canada Re: Dump trailer [re: stumpfield]       03/07/06 10:24 AM Edit   Reply   Please do us all a favor and get some practice welding before you make a trailer and take it on the road. Egon Post Extras:       stumpfield Member Reged: 12/27/05 Posts: 31 Loc: usa Re: Dump trailer [re: egon]       03/07/06 03:27 PM Edit   Reply   Thank you for the advice Egon. I own a little lincoln handymig for many years and have welded a lot of stuff. Since it's a 110v light duty welder, I want to get a bigger one to take on the trailer project. Don't worry, I'll include a sign behind the trailer "made by stumpfield" so you'll know it's me. Post Extras:       egon Veteran Member Reged: 09/12/02 Posts: 3011 Loc: Nova Scotia,Canada Re: Dump trailer [re: stumpfield]       03/08/06 05:12 AM Edit   Reply   stumpfield: Opp's; foot in mouth has struck me again. Seems to be a fairly common occurence. Soon outside weather will be here and I can go outside rather than make attempts at missinformation! Egon Post Extras:       Pat Veteran Member Reged: 09/15/02 Posts: 4889 Loc: SouthCentral Oklahoma Re: Dump trailer [re: egon]       03/08/06 05:47 PM Edit   Reply   Regardng welders and weldors... This weldor uses two arc welders. I have a 120 volt MIG which has abilitiy to use shielding gas but I just use InnerShield (flux cored wire) that is god for up to 1/4 inch on mild steel with multi-pass techniques. I also have an AC/DC stick welder for heavier stuff. Both are Lincoln brand, both were bought new, both are getting old (like me) and neither has ever had a single problem of any kind that I didn't precipitate through my stupidity. Neither has ever had any repairs and they just keep on working and seem to thrive on abuse. If I were to build a trailer (I don't do light duty trailers) I'd use the MIG for tacking and fitting and any light duty areas of construction and get to the serious work with the stick machine. If you buy a larger stronger MIG that woild replace the stick welder but wold probably cost considerably more than the pair like I have. STICK TO A MAJOR NAME BRAND Lincoln, Hobart, etc. Not Harbot Freight or Home depot, JC Whitney or... Pat "I'm not from your planet, monkey boy!" Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Pat]       03/08/06 09:09 PM Edit   Reply   I'm not exactly sure how I would utilize a "little" mig welder. Multiple passes don't seem to work for me on thick material the few times I have tried it with one of the 120V "little" MIGs. Stick electrode is good for jobs where the MIG will not reach, or where the material is particularly cruddy. I don't have a DC stick machine right now, only a crank-front tombstone Lincoln, so I weld just about everything with the more robust MillerMatic 35....a 1977 model MIG which has been a superb machine once I threw the Miller gun in the trash and got a TWECO. CJDave Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: CJDave]       03/14/06 05:59 PM Attachment Edit   Reply   Well, I mounted the pump temp. and hooked the jumper cables to my truck battery. It takes 27 secs to go from all the way down to all the way up. The dump angle is 50 degrees so stuff should slide out pretty well. This pic shows it in the dumped position with it sitting on it's own wheels. I worked on it 3 hrs today and have the pump permantly mounted and the rest of the cross members in. Only a few of the X-members are in on this pic, because it made it easier to mount the pump and battery box without them being in the way. I should get 3-4 hours on it tommorow and except for the sideboards it should be nearly finished. I'll post some pics tommorow. Later, Nat Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       03/14/06 08:27 PM Edit   Reply   You will no doubt be wanting to box those two pieces of channel that the ram connects to. As you know, channel has no resistance to rotation, so the ram will wind them up once it has a big load to push against. A skip-welded piece added on is all it would take to make them a square, and a super twist-resister. CJDave Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: CJDave]       03/15/06 07:17 AM Edit   Reply   CJDave, it's kind of hard to tell in the pic, but on the bottom cyl anchor the is a piece of 1" X 3" X 5" bar that is face welded to the channel seen in the pic. What isn't seen is that the 3" diminision is welded to the chanell and the 4" is welded to a tube that extends from it under the channel to the next channel abd that there are 2 pcs 3" channel that extend from it out at an angle and connect to the place where the tongue meets the front frame. I'm not worried about it twisting that channel as it's load will be straight down. The one place I'm not positive about is the top channel. I have a simular lug face welded to the channel and a piece of 4 X 3/8 flat bar welded on top and connected to the angle in front of it. That should stop it from twisting since it will be welded to the underside of the steel floor. My thoughts are that with the combination of the channel/lug/flatbar to angle andall being held in place by being welded to the floor it should, REPEAT, should stay, but I'm thinking a couple diagonal braces from the back of the channel out to the side rails is cheap insurance. What do you think? Later, Nat Post Extras:       twstanley Gold Member Reged: 09/27/02 Posts: 260 Loc: NE of Kansas City, Missouri Re: Dump trailer [re: Nat]       03/15/06 08:54 AM Edit   Reply   Nat, after reading CJDave's suggestions, your idea about putting the angle pieces leading from the back of the upper cylinder mount was what I thought I would do in your situation. I would think that would stiffen up that channel nicely, and put in the rotation stop as well. Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: twstanley]       03/15/06 01:42 PM Attachment Edit   Reply   I went out to the shop and took some more pics as more progress has been made. This shows how I have the anchor end cyl mount made. I have a piece of 5" chanel across the subframe on the bottom side at the back of the tongue and another 30" farther back, both are under the subframe. I then ran 2 pieces of 3" chanel from where the tongue crosses the front of the subframe back to the botton of the first 5" chanel. I then ran a piece of 5" chanel flat under these from where the 3" chanel connects to 4" past the rearward chanel. This is where the anchor for the cyl fits. In order for this mount to move it has to push the mount back, and that is stopped by the 3" chanel. The 5" chanel is welded under the subframe and just welding it isn't enough so I made these brackets to give me more welding surface. They weld inside the subframe and weld vertically to the cross chanel. I hope this pic shows what I mean. later, Nat Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: Nat]       03/15/06 01:48 PM Attachment Edit   Reply   The live end anchor is shown in this pic. It is a 5"chanel welded across the main frame. I welded the mounting lug to the chanel and then welded a 4 X 3/8" flatbar from the chanel connecting the lug, the 5" chanel and the next forward cross member. Then the floor will be welded to all of this. In order for it to move it would have to bend the 4 X 3/8 plateand the 5" chanel and the 2X2 cross member and shear the welds where the floor is welded down. By welding it to the floor I actually am making a beam that is 12 foot high as the floor is welded to each and every cross member. I hope this pic show it more clear. Later, Nat Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       03/16/06 05:25 AM Edit   Reply   A small piece of flat bar welded to the back side of that live end channel and extending over to the next crossmember is all it would take to stop rotation. Weld the flat bar with the flat side vertical of course. It would sort of be like the heavy piece that the cylinder attaches to was stuck clear through the channel and welded to the next crossmember. CJDave Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       03/16/06 05:32 AM Edit   Reply   One flat bar on edge right where that battery is would perfectly bridge between the two channels and stop rotation. CJDave Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: CJDave]       03/16/06 06:44 AM Edit   Reply   Dave I welded 2 pieces of 3X 2"angle extending out from the back of the "live end"at an angle going under the next cross member and connecting to the outside frame rails. Now I know it won't rotate and it can't push the chanel back. Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Nat]       03/16/06 07:19 PM Edit   Reply   Yeah, .... I'm visualizing that......it'll definitely do what needs to be done CJDave Post Extras:       Pat Veteran Member Reged: 09/15/02 Posts: 4889 Loc: SouthCentral Oklahoma Re: Dump trailer [re: CJDave]       03/17/06 04:01 PM Edit   Reply   Say, Nat & Dave (et al), What do y'all think of the idea of making a dump box to be added when required as an accessory to my 12,000 LB gross weight all steel util trailer? I would want all the hydraulics built into the dump box so it was not with the trailer when the box was removed. This will take up a little bit of the available volume but I think I will be weight limited not volume limited since I don't forsee hauling low density cargo. The tare on my trailer is a tad under 2000 so with the weight of the dump box added to the mix I should be able to safely dump a payload of at least about 8000 LBS or a bit more. If I dump over the back (originally considered a side dump) I could install some jacks in the back to stabilize it and prevent too much negative tongue weight. I should think a "socket" (depression) to retain the lower end of the dump cylinder should work fine with no permanent connection to the cylinder at the bottom end since the rig would be power up and gravity down. With the "ignition" switch of my Dodge/Cummins pick up in the run position a solenoid connects the paralleled 12 volt starting batts with the 220 amp 12 volt batt I have in the form of 2 each 6 volt golf cart batts mounted in the service body. These can be tapped to provide the "juice" to run an electricallyl powered hydraulic pump. Every time you "run" the truck it charges the golf cart batts or if you leave it running you tap into the capacity of the two starting batts as well so powering the pump should not be a problem. Alternator is rated well over 100 amps. I think this should be feasible but have no direct experience and NEED some reassuring consultation. Pat "I'm not from your planet, monkey boy!" Post Extras:       egon Veteran Member Reged: 09/12/02 Posts: 3011 Loc: Nova Scotia,Canada Re: Dump trailer [re: Pat]       03/17/06 04:55 PM Edit   Reply   Entirely feasable. Just a skid you winch on and off that contains the ram and box. At 8000 pounds and asumming granular material I'd just put a big inverted v in the middle of the box and have opening side plates with a manual latch. Wouldn't require all that extra equipment. The 8000 pounds would translate to approximately three yards of granular material so room isn't a problem. Egon Post Extras:       Nat Gold Member Reged: 12/14/04 Posts: 282 Loc: Lexington NC Re: Dump trailer [re: egon]       03/17/06 07:24 PM Edit   Reply   Pat, that sounds like the in bed dumps that are made for pickups. A friend of mine had one that went in the bed of a truck and would dump 4000 lbs. It had a pump/valve/res/motor hooked to a scissor hoist. I didn't know he was getting rid of it or I would have bought it. He sold it for 500.00 This unit just slide in the back of a truck, and you could make one that slide on a trailer just as well. You could make some brackets that would allow you to bolt it in and remove them to take it out. I would think it would be the same as building a trailer except no tires/wheels/axles to buy and no tongue. Don't you have a loader on your tractor? Just lift the front and back the trailer under it and let the front down and drive the tractor around to the back and lift and push. I have a 5" bore 2 stage dump cyl that you can have, I'll be out that way week after next, Let me know. BTW it is to much for an electric pump unless you build an aux. resevior. I put it on the trailer I'm building and it would run out of hyd fluid just as the second stage was starting. BTW I got it done today except painting and putting the side boards on. I'm going to do that tommorow, I'll take some action pics then. Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Pat]       03/18/06 11:25 AM Edit   Reply   That's a great idea. How about this twist. You make a removable "patch" in the rear area of the trailer deck that the material can flow though. The dump section is short enough to where it will end at the open area, and that way you can avoid the outrigger problem. It doesn't take much of a dump body to haul several tons. I secretly am always on the lookout for a steel tank like a 500 gallon propane tank that I can cut up and make into a drop-in-slide-in you name it dump bed for my pickup. You no doubt have seen debris trucks that are made from old boilers cut in half horizontally. The electrical system that you describe is exactly the same as the one I devised for an electric hoist that I had on my service truck. The starting batteries of the truck were isolated from the hoist battery group by a solenoid. Once the truck engine started, an oil pressure switch fed current to the solenoid which closed and connected all the batteries together. The idea was that on extended repair jobs we didn't want to inadvertently use up so much battery life hoisting that we couldn't crank up and go home. Of course on the way home that big Leece-Neville alternator pumped plenty of juice back into those batteries. CJDave Post Extras:       Pat Veteran Member Reged: 09/15/02 Posts: 4889 Loc: SouthCentral Oklahoma Re: Dump trailer [re: egon]       03/18/06 04:23 PM Edit   Reply   Egon, My limited experience and visualization ability prevents my understanding what you are describing. I don't understand the inverted V or the opening side plates. I thought about something like a five sided box with easily attached/detached hinges at the rear (opposite the ram assy.) The tailgate would be hinged at the top and could be manually latched and unlatched at the bottom like the 10 wheel dumps I used (hinged at top not the bottom like a conventional pickup.) If you think what you were describing is simpler or easier or cheaper to build or would work better then please try me again. Mabe a simple sketch if you have a scanner or post a snapshot of your sketch. Pat "I'm not from your planet, monkey boy!" Post Extras:       CJDave Veteran Member Reged: 10/21/02 Posts: 851 Loc: Southeast Iowa Re: Dump trailer [re: Pat]       03/18/06 07:47 PM Edit   Reply   Egon was describing the "fixed box" side dump rig, where the interior of the box has a mountain range running the length of it and the ridge of the mountain range runs front to back forming two separate valleys, one on each side. The valley is formed by the side of the box and the slope of the mountain range. The material is held by little gates that are in the vertical walls of each side of the box. By pulling the slides out you can dump the material out of the sides of the box; over the edge of the trailer, and onto the ground. There are actually quite a few applications that use this system. Some have the entire side of the box on a hinge at the top and a lengthwise bar holds the bottom from opening until the operator throws a lever and the bar flops down, letting the lower edge of the hinged side flip out, releasing the material. In point of fact, a side-dump "box attachment" would be a pretty good way to go with your existing trailer since you would have full control over the exact position on the trailer that you want the load to be. How about this: You make a setup which has two supports setting crosswise on the trailer, with a hinged dump box which has a floor that slopes to one side at about a 1:4 rise, and then on the high side have the dump cylinder. CJDave Post Extras:       Pat Veteran Member Reged: 09/15/02 Posts: 4889 Loc: SouthCentral Oklahoma Re: Dump trailer [re: CJDave]       03/19/06 09:49 AM