I am looking for a 20 ton or so air over hydraulic jack and 20 ton or so jack stands for jacking up my bus. Most of the jack stands are imported unless I want to pay big $$ and I'm not sure there is much difference. Is the Harbor Freight 20 ton jack any good?
Any recommendations here?
My personal opinion only....I am cheap and would use the imported jacks IF you can operate them remotely and never be in harms way while jacking.
I would not use cheap jack stands under any circumstances. Railroad ties or other hardwood cribbing would be my only choice.
I have seen jack stands break, fortunately with no harm done but it could have been a tragedy. Every jack stand in the shop got cut up and thrown in the trash that day.
I have the very heavy duty jack stands from HF and I am impressed with them. Obviously, they work well on concrete, but any other surface would require a cribbing process.
When I put the bus up in the shop, I use the bus mounted hydraulic jack/cylinder system that I fabricated. I then put jack stands in critical locations.
The cylinders have about a two foot stroke. Rather than run them all the way up (I like to have the bus quite a ways off the ground to service it), I put short pieces of railroad ties with a steel plate between the tie and the cylinder rod.
When I let the bus down last time I heard a pretty loud noise and thought the cylinder came down pretty fast. Turns out that the wood block split (even with a pretty big steel plate - probably not centered a good as it should have been).
In any case, my reason for this story is to caution folks to be very careful to make sure the wood blocks are in good condition!!!!
Jim
Harbor Fright's bottle jacks work fine for occasional use, and like anything made in the Socialist Workers' Paradise I derate them by half, in other words I use a 20-ton jack for a maximum of 10 tons. I wouldn't trust any of my HF jacks for their full rated capacity, but the 12- and 20-ton jacks lift my 26,000 lb bus with no problem.
I agree, some "affordable" stands look like a problem waiting to happen. I had the local lumberyard cut some 6 x 8" fir down to 2' lengths, and they are perfect under the tires when I lift the bus. I also bought some 12" squares of 1/4" steel plate to put under the jacks to spread their load.
John
Wood cribbing seems like a good alternative. I'm not sure I would use railroad ties as the ones most of us can buy are on their second or third use. Railroad ties are more suitable for landscape use than holding up a bus I think.
I doubt all imported jack stands are bad. Norco makes them in both the USA and imported versions. The only difference is the country of origin. Everything else is the same. The part number has an i appended when it is the imported version. A company like Norco or OTC would be accepting a lot of liability if they sold imported jack stands that would collapse under load.
I have had an air over hydraulic jack from HF for 5 orn 6 years and have not had any trouble with it. I do but air oil in in almost every use. I only use it on the bus so the use is not that much. I use wood blocks. We had some heavy timbers at work and I have some 12X12's that work well.
I have used what we learned at the Bendix class often and it is coming in very handy as I am putting ABS disk brakes on the 15 I am building.
Wayne
I am not a H/F type but to prove a point a friend was here for a couple months had 4 12t HF stands to prove a point (like I do sometimes) he let me put one in my press damn if it didn't take 49,210 # before it bent it never broke only bent at the top and his 20 ton 50 dollar HF jack worked as good as my $550 american made jack how long one will last I don't have any idea I know he has had the HF jacks for awhile
Quote from: rusty on June 08, 2012, 12:50:16 PM
I have used what we learned at the Bendix class often and it is coming in very handy as I am putting ABS disk brakes on the 15 I am building.
Are you doing something special to reinforce the axles to handle the disk brakes? The Bendix trainer said specifically not to retrofit air disk brakes to drum brake vehicles as the different stress points could break things. I would love to have air disk brakes for better stopping, but it would never be worth the time and money to convert.
I've got 2 air over Hydraulic 20 ton HF and they work very well and you can put a longer hose on them so you don't have to be under the bus to use it. I shove it under with a rod and pump it up with the compressor. I then crib under the supports with 4x4 Pressure treated on top of 3/4 inch ply pads 2x2 foot.
Another company that makes good ones is "Torin" I think it is called.
Dave5Cs
The backing plates and parts I have were sold to Eagle for use on an Eagle. As far as the rest of the suspension I am not doing anything else. I guess the ABS will but more strain on things but I would feel better with brakes that are much better than stock brakes. I will not make a habit of seeing if the ABS works. I only hope the one time I need it they stop me better than the stock brakes. I also hope I never have to use them to there full potential. The one place I hope the ABS help is the boggie axle. I always have them adjusted where they should be and with the proper weight, but I have slid the tires and flatspotted two tires. That puts a guy in a catch twenty two, if you back off the brakes to save the tires you mite not live long.
Wayne
I bought and used two 20 ton jack stands and two 20 air over hydraulic from HF to do my engine/tranny swap. They worked very well and was impressed that the hydraulic jacks have not drifted down under load. You can't beat the price and the jack stands are pretty stout.
Does Harbor Freight sell 20 ton jack stands? I don't see them on their website.
These are made in China but nice stands I have 4 made by Advanace TooL model ATD 7449 22 tons I payed 150 bucks for all 4 from a local tool shop in Vegas he made me a deal so he said ,I bought the pin type because for some reason I don't trust the claw type jack stands
Brian, I looked at my HF jack stands and they are rated at 12T. I think that is the largest set they sell.
The way I use them, they are probably at about 60-80% of capacity. I feel fairly safe, as I leave the hydraulic cylinders extended. While they no longer "support" the load after a bit of time (try to start out with the cylinders supporting most of the load), they would "catch" the bus if one of the jack stands failed (unless the hydraulic hose failed).
I always try to have two forms of support when I am under the bus.
Jim
My apologies, they are 12 ton. I'll be quiet now!
12 tons should hold a bus easy it's not like you are setting on 1 jack with 40,000 lbs on the 1 jack 4 = 96,000 lbs then you have a safety factor built into each they never rate the stands to the max fwiw and check the yard sales the old screw type bottle jacks make good stands
I must say that I do not have great faith in jack stands, although there is plenty of experiance to say I am wrong. Since we are on dirt anyway, wood blocks is the way to go.
12 ton would work as that is 48,000 pounds for two stands. I think I was forgetting to multiply by two. Are the ratchet style jack stands as good as the ones with the pins? The ones with the pin seem like they have nothing to stop the any movement. The ones with the ratchet at least have a flat V to kinda hold things. Obviously whatever axle is on the ground needs to be chocked.
I assume a 12 ton jack might be good enough too?
I probably have much faith in jack stands as I do wood. Wood can split. I would probably use only the best quality wood like white oak. I wonder if LVLs would work for cribbing? There is a large manufacturer just down the road that might have scrap stuff cheap.
Paul, it sounds like I might have upset you. Certainly not my intention. Indeed, I did not see your 20T number when I posted.
I use a homemade jack stand in the front (center) and the two HF 12 T jack stands behind the rear axle on the engine cradle rails. As I reflect on my bus weight and the location, I probably overstated the percentage of capacity I am using - probably closer to 50%.
As Clifford pointed out, ratings are "always" less than ultimate capacity. Different products have different rating/ultimate ratios. For example, hydraulic hose standards dictate a minimum of 4:1 (burst to rated pressure). Clifford's testing would suggest that they use a 2:1 ratio. That said, if the product is not somehow regulated by an industrial standard, the manufacturer can fudge the ratings.
I was at an IHC truck dealer today and saw the jack stands they sell. The sliding/mating parts are made with square tubing and the height adjustment is via a pin. Pretty fool proof. My gut feeling is that a pin is more robust than a "ratchet" mechanism. I was going to make my own stands and they would have been very much like the IHC units.
The link to the HF 12T stands is: http://www.harborfreight.com/12-ton-jack-stands-34924.html (http://www.harborfreight.com/12-ton-jack-stands-34924.html) . I don't recall paying that much.
Jim
Jim, I like the pin type check out the Advance Tool ATD 7449 stands they are pretty beefy and most shops use that type as long as the stand meets ASME/ANSI/PLAD specs you are good to go no matter where they are made
good luck
Clifford, you make a good point about meeting an industry standard (ANSI, etc.). I spent some time going over the HF pages for the 12T stands and there was no reference to meeting any standard (including the manual).
What I did find was
mind blowingQuoteItem 34924 12 Ton
Capacity 12 Tons (24,000 lb.)*
Height Range (Approximate) 19-1/2" – 30-1/8"
*Evenly distributed across two Jack Stands.
Repeat: *Evenly distributed across two Jack StandsThat, clearly in my mind, is false labeling - they are 6T jack stands!!!!
BTW, I agree, I would prefer the pin type stand
Jim
You guys do what you want but there is no way in hell that I would get under a bus on those jack stands.
Quote from: Len Silva on June 09, 2012, 04:53:48 PM
You guys do what you want but there is no way in hell that I would get under a bus on those jack stands.
Care to elaborate on why not? Are you just talking about the imported jack stands, or any jack stand, even a set made in the USA by a reputable company?
I would be more reluctant to get under a bus supported by wood than one supported by a decent jack stand. I would be worried the whole time I was under there about the wood cracking and splitting, or the stack of wood shifting and collapsing. I'm sure there are proper ways to stack cribbing, but I don't know the proper way and wouldn't know if someone else did it right or not. I don't believe I've seen a professional shop using wood cribbing. The bus shop I normally use for lubing my bus and such has several hydraulic lifts to lift up buses.
I don't do wood or dirt lol
good luck
I've had pretty good luck lifting with this one http://www.northerntool.com/shop/tools/product_200485232_200485232 (http://www.northerntool.com/shop/tools/product_200485232_200485232)
I do use jackstands, but also I set up some safety-wood in a couple of places just in case ..
I have the 20T air over hydraulic HF jack which I have used to good effect. I have about 300 pieces of 4x4 cut into 2' lengths I use for cribbing and blocking.
When I was a younger man, before I found out I wasn't invincible, my Dad and I used 5 ton napa jackstands to change rear tires on a loaded grain truck on the side of the road. We had to hurry as it slowly pushed the jackstand into the asphalt. Gives me the shivers to think about it now. I think we had 8 ton on that corner according to the elevator scales. It was an old international truck (i guess it wasn't that old, heck it's only a year older than my bus) that had 900-20's on it with steel 6 bolt rims that kept cracking around the lugs because it was so overloaded.
I have a couple of the 20 ton HF air/hydraulic jacks and love them. In the 9 years we have had the bus we have always been on dirt or gravel so i don't have or use jack stands.....i use wood blocking. Starting this fall we will be on concrete but i will still use wood. In Yuma there are a lot of earthquakes and i don't want the bus to fall off of a jack stand. I use enough blocks that the bus could move at least a foot or more in any direction without coming off of the blocks. If i have the wheels off and the project is going to take more than a day, i put them back on at nite. A few years ago i was working under it and the neighbor lady asked if i had felt the earthquake. I said "no, when was it", expecting her to say sometime during the nite. She said, "5 minutes ago". I was so busy i never noticed a thing....really glad i had a lot of blocks under it. ;D
I have no idea of the quality of the HF stands but their tonnage per pair is the same way the stands Clifford recommended are rated.
http://atdtools.com/7447 (http://atdtools.com/7447)
Frank
Where would one buy good oak or other strong cribbing?
Quote from: rv_safetyman on June 09, 2012, 04:30:53 PM
Repeat: *Evenly distributed across two Jack Stands
That, clearly in my mind, is false labeling - they are 6T jack stands!!!!
Someone once gave me a 'gift pack' type thing which contained two axle stands and a trolley jack. On studying the packaging I was also scandalized to find that the load rating marked on each stand was actually for both of them used together. It shouldn't be allowed..
Just today I've been pricing up some paint for the bus, and kept clicking on adverts that said things like "5 litre paint deal.." only to find that it wasn't 5 litres of paint at all but a pack with half the volume made up by cheap thinners. That shouldn't be allowed either.
Quote from: belfert on June 11, 2012, 03:46:51 PM
Where would one buy good oak or other strong cribbing?
My first thought would be to find somewhere that sells reclaimed railway sleepers (railroad ties?). Garden centres sell at lot of them for people doing landscaping work.
Jeremy
Southern yellow pine is structural rated, so you can predict it's behaviour under load.
I'd prefer pressure treated southern yellow pine for cribbing. Can be stored outside when not needed under the bus.
Luvrbus, would you happen to remember what shop in Vegas you got those jacks at, lvmci...
I don't remember the name but he was on Charleston Blvd not very far from the big upholstery supply on Charleston a small tool store and I think he was mobile also I have saw him in Lake Havasu before, cash talks with him like it does with everyone in Vegas lol
Quote from: Jeremy on June 11, 2012, 05:12:30 PM
My first thought would be to find somewhere that sells reclaimed railway sleepers (railroad ties?). Garden centres sell at lot of them for people doing landscaping work.
My concern with railroad ties is many of them I see have cracks or splits in them. There might some good ones, but I've never looked all that close at them. There are places all over to buy railroad ties.
Railroad ties are "USED" and have been under more weight than you or I can imagine or want to know about.
I have some I cut at an angle and I drive up on them (four pieces one under each drive) and I don't worry a bit about them letting the bus down. I mean what are they going to do evaporate??
Just my way
YMMV
Melbo
On the subject of rejecting wood as being weak because of cracks and splits...if you look at wooden beams in old houses, or wooden masts on old sailing ships, they invariably have lots of cracks and splits in them. I've seen cracks in masts which are 6 feet long and wide enough to get your fingers inside, but those masts are still entirely satisfactory - it was pointed out to me once that a longitudinal crack in a length of timber is like the thin vertical element in a steel I-beam - the strength comes from the bits on the outside, and as long as the bits on the outside are still held together the strength remains.
But masts and house beams are in tension of course, whereas blocks of wood under a bus are in compression, so the same logic doesn't necessarily apply
Jeremy
If the railroad removed a tie because it wasn't strong enough for railroad use do I really want it holding up my bus? I do find it interesting that almost every picture of used oak beams for sale on Craigslist shows cracks in the beams. I need to go over to place locally that makes LVLs and see what they have for cheap or free scrap pieces.
I seem to remember that some pallets are made of Oak. You probably have either a pallet manufacturer or pallet recycle business in your area.
The cross members are not large (3x3?) but they would make a wonderful "Lincoln log" type cribb and that would be quite stable. They may also have raw wood that they could saw larger sizes for you.
Jim
Brian,
The rail road right across the hwy from us is a major rte. (like 8-10 trains or more per day)
And they come through once a year and replace EVERY tie.
As a matter of fact there are 2 bus size piles of the used ties about a 1/4 mile from us now.
As far HF jacks go we use both the 12 & 20 ton air overs around the shop and they typically last us 2-3 yrs each with fairly heavy use. @ less than $80 apiece I just throw them away and buy a couple more when on fails. (a lot cheaper than some of the $500-800 jacks I've had that lasted less than 10 yrs.)
;D BK ;D
For jack stands, I took a short section of 8" I beam, chopped it into four pieces and welded 1/2" plate on the top and bottom. A 4' section of red oak 4"x4" chopped into 12" pieces allows me to add cribbing if I need to. The I beam is used vertically - no way to break or compress it with a bus. I can lift the bus with my hydraulic levelers, slide the jack stands under the frame jack points and have plenty of clearance. My front stands are 2" taller than the rear due to the higher ground clearance up front.