PLD 14 Report post Posted July 6, 2005 If you had a 10ft single axle trailer, a 275 gal tote tank, and a 550# skid unit which would you put over the axle; The skid or the tank? Logic tells me the tank, but 550# load with it's CG halfway between the axle and the tongue is going to make for a pretty substantial tongue load. Right now I have a 30gal tank and a 220# PW forward of the tank and the tongue weight is pretty beefy. Total space behind the tank is about 18in. Space forward of the tank is about 5ft. Space on either side of the tank is just big enough for a 5 gallon bucket. Philip Share this post Link to post Share on other sites
jason c. 14 Report post Posted July 6, 2005 are you going to be travelling with it full? a gallon of water weighs 8.34lbs. full your tank would weigh close to 2300lbs. i believe that the heaviest of the two should go over the axle. a 275 gallon tank is pretty heavy empty. maybe you could spread out the weight with your skid partially over it and your tank partially over it...im no expert but i have recieved some valuable info here and im just throwing out some ideas that may or may not help. Share this post Link to post Share on other sites
Joe Ragsdale 14 Report post Posted July 6, 2005 You want to put the heavier weight over the axle or just forward of it. This would probably be the tank. If there is enough room in front of your tank, position your machine forward or backwards so that you have a reasonable tongue weight. Ideally, your tongue weight at the hitch should be in the 200-230 lb range, but it can be more depending on the load capacity of the towing vehicle. This scenario should give you the ability to tow with the tank full or empty. Share this post Link to post Share on other sites
Celeste 341 Report post Posted July 6, 2005 You need to center the tank over the axle. Then put the skid in front of the tank. If you dont do it like this the trailer will have a mind of its own. Look at some of the other rigs on this site or on other sites to get an idea. You should have room on the back for your reels. What weight axle is under the trailer? Most 10 ft. trailers comes with 2000 to 3500 lbs axles. ( if you over load the trailer you stand a good chance of breaking the springs or the axle) You can get a 6000 lbs. axle for it. Next question. Does the trailer have brakes on it? If it doesn't then I would look into a good set of electric brakes for it. Roger Share this post Link to post Share on other sites
RyanH 14 Report post Posted July 6, 2005 From a balance point of view, if you keep your tank full (or even 75% full) all of the time, I would position it so that 80-90% of the tank footprint is over the axle. Keep about 10% overhang towards the front of your trailer. Position your skid unit behind the tank. The idea is to keep your *center of gravity* directly above the axle. If your tank is slightly forward and your skid is behind, you keep enough weight on your tongue. Use the lever rule to give a more exact location. The equation (torque balance) works out to: F = [ Wu(La - .5*Du)/(8.4*Vt) ] + .5*Lt Where: F = Distance from the axle center to the front edge of your tank Wu = weight of your skid unit (550# here you said) La = Distance from your axle center to the back of your trailer Du = Depth of your skid unit Vt = how much water is in your tank (in gallons) Lt = the length of your water tank (as measured perpindicular to your axle) Keep all length measurements (F,La,Du,Lt) in the same units (inches, feet, mm, furlongs, etc.) Of course, this doesn't include the weight contribution of your other equipment, but it should give you a pretty close figure to use in setting up your trailer for optimal placement. Share this post Link to post Share on other sites
Scott Stone 604 Report post Posted July 6, 2005 Uhhm, am I the only one who's eyes glazed over with Ryans calcualtions??? I have the washer forward of the tank on both of my trailers, and I am putting a new one together tomorrow, and the tank will be forward on it, as well. Scott Share this post Link to post Share on other sites
PWkid 79 Report post Posted July 6, 2005 In my humble opinion,that much potential weight needs to be on a dual axle trailer,they aren't that much more expensive and will solve most of his questions. Share this post Link to post Share on other sites
Don Phelps 85 Report post Posted July 6, 2005 That's an absurd amount of weight for that size trailer. A 6x12 tandem axle is a much more realistic and safe choice. But to answer the question, the tank slightly off center to the front, over the axle. Share this post Link to post Share on other sites
PLD 14 Report post Posted July 7, 2005 Uhhm, am I the only one who's eyes glazed over with Ryans calcualtions??? I got it, but then again I have a BS in physics.... Share this post Link to post Share on other sites
PLD 14 Report post Posted July 7, 2005 That's an absurd amount of weight for that size trailer. A 6x12 tandem axle is a much more realistic and safe choice. I agree. But.... I rarely haul water. I have actually considered dumping the tank on that trailer. Right now it has a 13hp pull around (bolted down) and does about 95% residential work. I want to upgrade to a 5.5gpm unit and hot would be very handy on concrete. The only reason to keep the tank is to buffer in low volume situations, hold my advertising signs, and occassionally haul some water. If the tank (loaded) were even close to the skid weight it would be a no brainer as the tank is almost never used. But at 2400lbs, placing it too far forward would nuke the tongue when full. Since I just bought a dual axle trailer I may just dump the tank and turn this into a skid only trailer for locations where water is available. Share this post Link to post Share on other sites
PLD 14 Report post Posted July 7, 2005 The idea is to keep your *center of gravity* directly above the axle. If your tank is slightly forward and your skid is behind, you keep enough weight on your tongue. Use the lever rule to give a more exact location. Good head Ryan. I was so focused on the positive moments adding to tongue load that I completely forgot to counterbalance it with the negative moments. This needs more noodling. The neg moment (trailer rear) has a much shorter max lever than the positive moment (trailer front). Careful placement could give me an approriate tongue weight with no water in the tank and a near zero (or negative) tongue weight with the tank loaded. Anyone know anything about negative tongue weights effect on the hitch and driving stability? Share this post Link to post Share on other sites
PLD 14 Report post Posted July 7, 2005 In my humble opinion,that much potential weight needs to be on a dual axle trailer,they aren't that much more expensive and will solve most of his questions. I don't disagree that it would be best on a tandem, but if you look the numbers. Max load ----------- 2400# water. 900# trailer. 600# skid. 300# junk. --------- 4200# - Just 20% overweight for a 3500# axle. Normal load ----------- 100# water. 900# trailer. 600# skid. 300# junk. --------- 1900# - 46% underweight for a 3500# axle. Share this post Link to post Share on other sites
racechaser 64 Report post Posted July 7, 2005 Uhhm, am I the only one who's eyes glazed over with Ryans calcualtions??? That's some pretty fancy calculations Ryan put up there. Myself, having no sheepskin and being slightly redneckish,I would have filled the tote up and drained it, continually moving it until I got the "look" of a balanced load. I told all my math teachers that numbers were meant to create words not solve math problems.I never thought I'd use stuff like that algebra they were teaching. BOY WAS I EVER WRONG!!!!! Thanks Ryan for all the scientific help you give to all of us.With that much calculation knowledge I'm really considering getting rapelling advice from you.If anyone can figure rope load and stress it would be you. Scott Share this post Link to post Share on other sites
Don Phelps 85 Report post Posted July 7, 2005 Uhhm, am I the only one who's eyes glazed over with Ryans calcualtions??? Actually, I rolled mine. My wife has her PhD. and she's a math professor here in Orlando. She doesn't pressure wash on the side. Anyone needing some numbers crunched, let me know and I'll get the right answer for you. Ps. Why she married me is still a mystery, but I think I know! :lgbugeyes Share this post Link to post Share on other sites
Don Phelps 85 Report post Posted July 7, 2005 I agree. But....I rarely haul water. I have actually considered dumping the tank on that trailer. Right now it has a 13hp pull around (bolted down) and does about 95% residential work. I want to upgrade to a 5.5gpm unit and hot would be very handy on concrete. The only reason to keep the tank is to buffer in low volume situations, hold my advertising signs, and occassionally haul some water. If the tank (loaded) were even close to the skid weight it would be a no brainer as the tank is almost never used. But at 2400lbs, placing it too far forward would nuke the tongue when full. Since I just bought a dual axle trailer I may just dump the tank and turn this into a skid only trailer for locations where water is available. For the most part, this is info that you didn't present when you asked the question. I have a 125 gallon tank on my 6x12 tandem for roofs and a 65 for a float and auto detailing as well as a 700 lb skid, two hose reels, 13 hp cold pw (for back-up) and various containers of chems as well as a tongue box and side box and ladder rack. A 425 gallon truck tank takes care of business (as needed) for those jobs where water must be taken with us to the site. It's mounted in a '01 Chevy Silverado 3500 when needed. Be safe! Share this post Link to post Share on other sites
Joe Ragsdale 14 Report post Posted July 7, 2005 Anyone know anything about negative tongue weights effect on the hitch and driving stability? Potentially VERY dangerous! The trailer will probably fishtail at faster speeds depending on the amount of negative tongue weight. Also, the possibilities are increased for hitch/ball separation depending on the type and condition of the hitch on your trailer. Just my opinion.... Share this post Link to post Share on other sites
jason c. 14 Report post Posted July 7, 2005 i think, one day in the very near future, computers will be the size of houses. and only the very wealthy will be able to afford them. Share this post Link to post Share on other sites
CCPC 26 Report post Posted July 7, 2005 i think, one day in the very near future, computers will be the size of houses. and only the very wealthy will be able to afford them. Huh? I thought we were talking about tanks and trailers. Share this post Link to post Share on other sites
tropical wave 22 Report post Posted July 7, 2005 i think, one day in the very near future, computers will be the size of houses. and only the very wealthy will be able to afford them. I think this post was brought back from April 1977......... Share this post Link to post Share on other sites
jason c. 14 Report post Posted July 7, 2005 im not trying to be smartaleck, but i think all of our opinions cover all possible configs. including a dual axle. Share this post Link to post Share on other sites
CCPC 26 Report post Posted July 7, 2005 I'm starting to have Gadget Flashbacks.:thinking: Share this post Link to post Share on other sites
PLD 14 Report post Posted July 7, 2005 im not trying to be smartaleck Isn't it great to succeed at something without even trying! :lgbounces Share this post Link to post Share on other sites
PLD 14 Report post Posted July 7, 2005 Potentially VERY dangerous! The trailer will probably fishtail at faster speeds depending on the amount of negative tongue weight. Also, the possibilities are increased for hitch/ball separation depending on the type and condition of the hitch on your trailer. Just my opinion.... Good info! Share this post Link to post Share on other sites
tropical wave 22 Report post Posted July 8, 2005 Isn't it great to succeed at something without even trying!:lgbounces too funny !!! I've got to remeber that one !! Share this post Link to post Share on other sites
PLD 14 Report post Posted July 8, 2005 too funny !!! I've got to remeber that one !! Be my guest, I stole it from someone else. I think it was in reply to me saying, "I'm not trying to be an a**hole or anything..." Share this post Link to post Share on other sites
