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Dennis Davidson Posted: Jan 30, 2010 09:11 AM	Generator/Compressor Units I'm putting together a new spray rig and was looking at getting a gen/comp combo unit. Anyone have one or know of someone with one? Are you satisfied with it?
Posted: Jan 31, 2010 01:54 PM	I have a John Deer with a 40KW genset and 40 cfm screw air compressor unit all in one, running an E-30 and EXP-2 and have had no problems with the unit. These things are quite heavy as you can't set the individual parts in different areas, so that is something to also consider.
Dennis Davidson Posted: Feb 01, 2010 09:37 AM	Thank's for your input. I'm more concerned with space than weight. You make a good point though, wouldn't want to put that much weight in a standard rig. With two G-250 units with 360' of hose each, generator/air compressor, primer pump, mixers, drum heaters and tools all in one compact (16') rig, space is at a premium.
Posted: Feb 02, 2010 04:17 AM	mac,,with the equip you describe you would have ~6k lbs of equipment,,,and you havent foamed or lined or rigged the trailer(or added scaffold,tools,microwave,sprayfoammagazine.coms 2010 calander & a box of kleenex) and other provisions,,,add 4 sets of foam and you are out at 10k or so...now if you have the 7k axels under,,you are gettin real close to runnin this girl out at the edge when you are full of juice...10ply tires are in order and check the pressure regularly.. my next trailer will be 20' gooseneck on floor with 8' over,,with dual duals,, deck above duals..still compact enough to get into most places,,heavy enough to haul stuff with wt to spare,,,tall enough to keep from draggin the booty and bendin it to crap when backin in to some of the wild sites we are expected to get into...and i can still compartmentalize to allow some creature comfort for my crew(forward compartment=powerhouse,,rear compartment=processing station),,, 16' rigs are great for single processor units with 5-7.5 comp,,,shore hookup(god forbid,,lol)and the provisions,,jmho.. hope this helps stimulate the greymatter,,, 'dude
SPRAYFOAM GODDESS Posted: Feb 02, 2010 08:38 AM	Sold quite a few, no major problems, great footprint, plumb external filling, definatley place it over the axles.
Dennis Davidson Posted: Feb 02, 2010 09:10 AM	dude, this isn't my first barbecue. I knew someone would point out a weight problem. I don't intend to carry any materials. Your rig might carry all the important accessories like microwaves, calendars and Kleenex or maybe some pillows, but this is strictly a roof equipment rig designed to be as compact as possible. Having a 20' pb or gooseneck is fine for most spray applications. You can have a rolling shop in it. Been there, done that, still doing it! Now I'm putting together a lean mean sprayin machine so we can get er done! By the way, we custom build rigs too! I've just never used a combo gen/comp before.
Gerry Wagoner Posted: Feb 02, 2010 02:50 PM	Combo rigs seem to be a good idea---until the motor conks out. Then you lose BOTH air and power. Currently building a 32' gooseneck rig. Just the right size.. `oG
Dennis Davidson Posted: Feb 02, 2010 05:38 PM	Everyone has their own perception of how big a rig should be and what should be in it. As long as it satisfies your needs, then it's the right size. Regarding the combo unit. I figure it's just like anything else, if I start with a quality engine and components and keep up with regular maintenance, I shouldn't have to worry about it conking out for a long time. I don't have a problem with a single power source for ele & air. Can't operate without one of the other anyway. Thank's for all the in put.
Yvan Richard Posted: Feb 03, 2010 09:25 PM	I am also running a 16 ft trailer, with only one proportioner and one hose. I have room to spare however I would like to put my 25kw gensent in the trailer for many reasons. I have a seperate gas powered air compressor. The trailer has 2 3500lb axles. I do normally only carry 2 sets with me. Is putting the genset in the trailer possible?
SPRAYFOAM GODDESS Posted: Feb 04, 2010 08:16 AM	I would get your trailer weighed first to see what # you have to play with. Next, check your spacing on the support beams, make sure you have good support. Machine, compressor and foam/poly are going to be near 2,000 lbs, I don't know what a 25 kw weighs, but I know a 40 is near 2500 lbs. I would also check with your axle mfr, possibly Dexter, to make sure what their restrictions are, generally a 5 yr warranty on axles = you don't want axle problems.
Dennis Davidson Posted: Feb 04, 2010 08:52 AM	To be safe, check with the trailer mfg. If you mount the gen in you trailer, put is across the front axle or just ahead of it. You'll need to put up a barrier wall to separate it from the work/storage space and you need vents in both sides of the trailer for air flow. You can plum the exhaust out the bottom through the floor. This may sound obvious but I've seen generators mounted in trailers...unvented. They just open the back door for air. Saw one on E-bay a few months ago.
Michael Fusco Posted: Feb 06, 2010 03:54 PM	Uh.....no. First, even though you say you are not going to carry material, I would like to visit when you spray that last 1/4 of a set in your trailer, finish the job, then man-handle the drums out of your trailer so that your not overweight...that's what wee all do right guys?? No weight you say...maybe..but I'll bet that 650-800 pounds will make a difference, especially if you BALANCED the load. Then, even though you fuel up every day, and have a preventative maintenance program which everyone who goes near the rig follows religiously, I am SURE you will NEVER have a generator failure which will also drop out your compressor. And by the way, you will never use shore power...always want the diesel buring that cheap fuel. And when you vent it out the bottom....you will make sure your airflow is always away from your intake panel on the side right....gonna level the rig at every site...dont use a fan, let it vent naturally, or vent out the top (hot air rises)....and that will help the generator immensely...getting all that preheated products of combustion in there..... I love it when we know more than guys who build rigs for a living....then save that money...just to spend more than what we saved later. Some of the "professional" rig builders cant get it right...watched a Demilec dealer drive down the road in a trailer crab walking just the other day. Give him 6 months before it vibrates itself to death. Buy cheap....get cheap....don't skimp on your livlihood. ...And before everyone jumps on me....no, I do not build rigs...but did...once.
Dennis Davidson Posted: Feb 06, 2010 06:23 PM	Like I said before, this isn't my first barbecue. I've done it this way for a long time, just in a little larger trailer. The way I'm set up I don't have to man handle any drums. The rig assembly I have in mind is in no way "on the cheap". The trailer isn't going to be an off the shelf Haulmark. It will be custom built from the ground up. I'm not trying to tell anyone how they should build one, I'm building this one for my specific needs, integrating a system that already works for me.
Circle-D Posted: Feb 23, 2012 11:51 PM	Anybody ever seen a weight rating on the gooseneck portion of the trailer. I've asked several mfgs. how much I can haul on the upper deck. They all "think" 1500 to 2000 lbs but it doesn't seem like anyone knows for sure. NextGen has their 35/35 combo unit that weighs in at 1500 lbs and is short enough to stick up there out of the way. It seems like that would put a lot of weight on the rear of the truck. 3 sets would certainly balance it out when you were full. Any thoughts?
Dennis Davidson Posted: Feb 24, 2012 06:31 PM	1,500 lbs is about right on the goose neck's riser deck but I wouldn't suggest putting that much up there. I have a 36' with a 60k (2,600lbs full) on the floor of the trailer and it's hard to crank the jacks up and down. Just bought a 30' goose neck and will be putting the generator farther back toward the axles this time. I decided to go with separate generator and air compressor mainly to help distribute the weight putting each component in a different area of the trailer. BTW, I do use shore power when ever it's available.
Circle-D Posted: Feb 24, 2012 09:19 PM	I will have the electric landing gear on the trailer. I'm still waiting for the mfg to give me a load rating on them also. Genset may go on floor and the compressor, tank and dryer in gooseneck. They should total around 600-800 lbs. The stand alone 40kw is from 1200-1625 lbs depending on make.
mark moyer Posted: Feb 27, 2012 09:56 AM	skip...got air pigs and compressor skid up on my dog house,,,i would not put my air dryer up there next time,,,looks perty,,design poo poo..air dryer,,hot meets cold...and it is hotter than miss..oh yeah where is that dangfangled calandar???serious heat,,plan on more than just the roof vent,,,we got a fan under ours and a louvered sidewall vent for the extra heat,, so you gonna get one of them fancy elct/hyd landing gear thingys eh...???life must really be good... priced one on this new trailer build,,,right at $2K,,,sheet the bed fred,,we be crankin,,,
John Shockney Posted: Feb 27, 2012 10:09 AM	From my experience the only challenge with extra weight up over the gooseneck is the towing truck’s gvwr trailers generally tow better with more weight forward. Though you should check the lift rating on your electric landing gear there are some that are only rated for 2,000 pounds or less and that would be pushing their limit, that’s when things break. Also check what the tongue weight rating for your hitch is. Airpro
Circle-D Posted: Mar 06, 2012 08:22 PM	One trailer mfg. today stated they would not warranty the gooseneck trailer if I put the generator on the upper deck. Anyone else ever run into this? Anyone have there genset on the upper deck? The electric landing gear is rated for 10k and the hydralic is rated at 24k. They said it would "sway all over the road" if this much weight was up front.Any thoughts?? more importantly any experience?
steven argus Posted: Mar 07, 2012 09:40 AM	Skip, We're planning a build as well and have a lot of the same concerns you do. As far as too much tounge weight, I believe that is pretty hard to do. More tounge weight, the better, as long as the tow rig/ ball mount can handle it. Dualies are the way to go with adjustable air bags out back. About "swaying all over the road", I think they might be referring to having too much weight up high instead of on the floor. Landing gear is going on our rig as well. Friday night, 9PM, snow storm, cutting into my Miller Time... yup, landing gear.
Circle-D Posted: Mar 07, 2012 10:21 PM	Anybody ever hear of or own a generator sold or made by Bowers Power or Armstrong. They are out of Fla.? Seems like they have more features for the same dough as some of the other makes.
mark moyer Posted: Mar 08, 2012 03:19 PM	Nope,,,tons of builders,,,service,n parts after the sale and a service network maybe ,,,,,hmmmm So what features u need ? Serious? Most builders have multiple controller configs...u wanna talk 2ur pc from ur genset,,no prob.,,,pony up,,,,$$$$ Just add the bigger controller The usual,,on,,off,,over temp,,oil press/ temp, should work in most hillbilly foam rigs Unless u use diaphragm pumps and or ramp doors
Mark Mouton Posted: Jun 06, 2012 07:36 PM	I ordered the 35/35 from NexGen. Manufacturer says the rotary vane compressor is capable of 100,000 hours. That sounds like a lot but if it goes 1/3 of that I'll be ok. Also say air compressor puts out 90 degree air(has a built in cooler). We'll see. I like Kubota, got one on my Stantco 1800A blowing machine. good engine. I went back and forth on the screw and rotary vane, but here we go!!! Putting it on a 24' box truck. weight is not an issue
SPRAYFOAM GODDESS Posted: Jun 06, 2012 08:41 PM	Weight can still be an issue, seen lots of trucks and I mean 40+ that the contractor bought 19,500 gvwr or even 22,500 and they can only roll with 2 sets max. Dealing with a Mitsubishi that they won't cover the engine replacement cuz of the constant load - it's bull but yeah they bring me those freakn trucks that weigh 14,000 empty - oh I already bought it got a great deal. Oh yeah? For how long....I could go on but I am on my phone bored lol Empty weight plus fuel- both in truck n gen set, plywood weighs a lot, equipment 3000 lbs, tools, scaffolding, ladders, people, chemical - you add it up
Mark Mouton Posted: Jun 07, 2012 06:58 AM	Sprayfoam goddess, you have aroused my curiosity. What does the 3000# in equipment include? Reactor, hose, generator, air dryer? Those are probably close to 3000#! Then 4-sets=4000#. Plywood wall, scaffolding,work bench, tools, parts,maybe 2500# more? That is a load no doubt! But if it is loaded right, the truck will handle it and hopefully be a little under 26,000# gross. I think I should go weigh my truck after I get my new H-25 and generator/compressor installed
SPRAYFOAM GODDESS Posted: Jun 07, 2012 08:01 AM	I think you should weigh your truck before you start. I guess if its a 26,000 gvr then it will weigh 14,000 empty. Add 550 for liftgate. 1000 lbs for plywood, foam, hose racks, fresh air etc. We are at 15500 now add your machine and hoses 800-1000, 16500. Now add your generator & compressor with fuel 3000, 19500. Let throw in some tools, etc at 500 and a couple skinny guys, 20,300, fuel for the truck = 20500. Now, that is all light estimate - realistically they roll out finished without fuel in either at 21,500 with a John Deere and a RS compressor - I don't screw contractors with the cheap stuff. I am currently experimenting on a lighter version, actually just started today - I'll let you know in a couple weeks how it rolls - but it weighs in at 14860 with a 1/8 tank of fuel so far.
Mark Mouton Posted: Jun 07, 2012 09:36 AM	Sprayfoam goddess, Do you feel the Kubota generator/compressor is poor quality? Have you had problems with it or know people that have?
SPRAYFOAM GODDESS Posted: Jun 07, 2012 10:05 PM	I have only seen or heard of one issue kubota v3800 engine but it was taken care of pretty quickly. Haven't sold but 20 of them though. I thought the hydro vane was a good footprint and weight and enormous cfm but I tried two back in 06 n 07 - one to MS and one to GA, they had so many problems ...one of those contractors still doesn't talk to me - I tried the 7 and 11 models, not sure if they are the same still. Back then they were $5 and $7k cost - I hope they have made improvements or your in a dry climate. I just tell it like is...good luck.
Mark Mouton Posted: Jun 08, 2012 10:27 AM	Sprayfoam goddess,thanks for your input. Tossing things over
SPRAYFOAM GODDESS Posted: Jun 26, 2012 11:08 AM	posted this as a new topic of "truck builds"