Improving hydraulic bottle jack

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Nov 16, 2017, 02:30 PM
tonyfoale

4 Attachment(s)

Improving hydraulic bottle jack

A while back I detailed how I upended a bottle jack for use in a press.
See here http://www.homemadetools.net/forum/i...5188#post81319

It has had quite a bit of use and has worked fine. However, it recently developed a leak and dumped most of its oil over the floor. External inspection indicated that the oil had leaked through the ram wiper seal. Normally when the jack is right way up this seal is at the top and should never get flooded with oil and is only there to wipe oil off the ram and keep dirt out. When the jack is turned upsidedown there is oil wanting to escape 24/7, although that seal should be up to that duty it decided not to after some time.

I pulled the jack apart, I want to make some more mods to it and this was the motivating opportunity. I hadn't done it previously but I withdrew the ram and piston assembly and was fairly horrified to see that the cylinder appeared to be just a piece of thick walled DOM tubing with no refinishing, honing or grinding. Not ideal for a high pressure seal. This has a 55 mm piston and is "supposed" to be loaded to 16 ton. A quick calculation shows that the loaded pressure will be close to 60 MPa, that's not a trival pressure.

I decided to hone the cylinder to give an improved surface for the main seal. I have a high end cylinder hone but its minimum diameter is 72 mm so I had no choice but to use a Horror Fright version which would close down small enough.

Attachment 20480 Attachment 20481 Click on photos for full size.

Honing setup. Normally I use recirculating flood honing fluid to remove the refuse but that wasn't practical in this case because it was a blind hole, so I 3/4 filled the cylinder with fluid to at least get the junk away fro the honing surface. It would have been much easier if I had unscrewed the cylinder from the base but it resisted all my efforts to do that. I was concerned that any increased effort would distort the cylinder.

Attachment 20482

Here is the cylinder after a short bit of honing. The photo doesn't show all the way down inside but that pattern was repeated all the way down. It is obvious that there was a spiral high point around and along the cylinder. This was an even greater shock than finding the surface unfinished. I debated whether to leave well enough alone or continue honing until the spiral was gone. As best that I could I used a bore gauge to determine how much would have to come off to clean it up properly. It looked like I'd have to take about 0.05 mm off the diameter of the high spots to get the surface down to the low spots. I considered that preferable to the spiral so I continued honing. Rapid metal removal is not a strength of the HF hone and I had to hone away for half an hour to get the job done. My estimate of the final diameter was pretty close and I wasn't concerned that the seal would find it too large, on the other hand the seal should be much happier with a round cylinder.

Attachment 20483

The cylinder after honing. Compare to the initial spiral above. A quick test assembly demonstrated a more solid feel to the operation of the jack, previously it had a slight sponginess, that has now gone. In use the main piston seal must have been leaking a bit into the outer chamber, giving the non-solid feel. Tomorrow I'll finish the planned modifications and assemble it back into the press.

It is never good practice to place any body parts under anything only supported by an hydraulic jack, and the findings here only serve to emphasize why.
Nov 16, 2017, 07:09 PM
j.bickley

Quote:

Originally Posted by tonyfoale

It is never good practice to place any body parts under anything only supported by an hydraulic jack, and the findings here only serve to emphasize why.

Good point! Thanks.
---Joe
Nov 17, 2017, 06:49 AM
DIYer


Thanks tonyfoale! We've added your Cylinder Honing Setup to our Drilling and Drill Presses category,
as well as to your builder page: tonyfoale's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-cylinder-honing-setup"> <img src="/uploads/206976/homemade-cylinder-honing-setup.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-cylinder-honing-setup">Cylinder Honing Setup</a> <span> by <a href="http://www.homemadetools.net/builder/tonyfoale">tonyfoale</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/honing'>honing</a>, <a href='http://www.homemadetools.net/tag/cylinder'>cylinder</a> </div> </div> </div> </div>
Nov 17, 2017, 07:49 AM
nhengineer

My method of removing jack ram cylinders

Tony, excellent report. Next time you need to remove the ram cylinder, put the jack base in a large vice (at least 6"), well anchored to the floor, use a big MF pipe wrench with a long pipe (36") slid over the handle for more leverage (better use a Rigid, a Horrible Freight with probably bend or break). Finally, put the ram back into the cylinder exactly where you going to apply the pipe wrench (preferably at the very bottom). Get as close to the bottom as you can since the combination of the cylinder screwed into the base and the the ram on the inside will prevent distortion. I've been rebuilding jacks for 40 years and I have yet to deform a cylinder. When you put everything back together, use the same method. The internal pressure of a service jack is around 30,000 PSI so that requires a great deal of torque to seal up. Keep up the good work.
Nov 17, 2017, 02:31 PM
tonyfoale

Quote:

Originally Posted by nhengineer

Tony, excellent report. Next time you need to remove the ram cylinder, put the jack base in a large vice (at least 6"), well anchored to the floor, use a big MF pipe wrench with a long pipe (36") slid over the handle for more leverage

This is basically what I tried, but I got to the stage where I got concerned about breaking something. I had to google what a MF wrench was, it was what I tried but I am used to them being called Stillsons. Trans-Atlantic language differences.

Quote:

Originally Posted by nhengineer

The internal pressure of a service jack is around 30,000 PSI so that requires a great deal of torque to seal up. Keep up the good work.

In the case of my jack a calculation showed around 8,500 psi for max load.

There seem to be much better seals available than those fitted, it looks like most would require a different piston but that is almost a trivial thing to make. With your experience do you have any recommendations for a better seal type? I am thinking of a U seal with O-ring backup.
Nov 17, 2017, 02:43 PM
tonyfoale

I should have mentioned in my original post. that if anyone intends to follow my lead and hone a cylinder still attached to the base, that often there is a valve in the base which stands proud a little. To avoid wreaking that valve you need to ensure that you have a hard stop on the lower end of the hone stroke to prevent it bottoming on the base.
Nov 17, 2017, 04:25 PM
nhengineer

1 Attachment(s)

Quote:

Originally Posted by tonyfoale

This is basically what I tried, but I got to the stage where I got concerned about breaking something. I had to google what a MF wrench was, it was what I tried but I am used to them being called Stillsons. Trans-Atlantic language differences..

I'm curious what GOOGLE thinks a "big MF pipe wrench" is. Around here (central NH, USA) the "F" part is an expletive and the "M" part stands for mother. It looks like this Attachment 20494 only the handle is 48" long.

Here's the WEB page. https://www.whitecap.com/shop/wc/p/r...iABEgICk_D_BwE

Quote:

Originally Posted by tonyfoale

In the case of my jack a calculation showed around 8,500 psi for max load.

There seem to be much better seals available than those fitted, it looks like most would require a different piston but that is almost a trivial thing to make. With your experience do you have any recommendations for a better seal type? I am thinking of a U seal with O-ring backup.

Back 30 or so years ago I purchased my parts kits from The Jack Pack & Tool Company on N Marianna Ave, Los Angeles, CA. They are out of business - couldn't compete with $25 Chinese throwaways. Now, if it won't hold the weight, I put in a new ball check (from McMaster-Carr). The ram cup is usually not available but ram cups seldom are the problem anyway. The only other "seal" is the shaft wiper (and now-a-days that usually just a standard O-ring), the release needle valve housing and the pump ram (and they're usually just O-rings too). I've seen some jack rams with double or triple O-rings instead of a cup. That kind may NEVER give satisfactory results under max load after a bit of use and maybe not even when brand new.

Basically, if it won't hold the weight, it's the ball check and that's just a commercial steel ball bearing. If the ram cup is worn out, I trash the jack because, if it's worn out by spending its life in nice slippery hydraulic oil, it's seen a great deal of use and time to be retired. Same deal for the pump ram. The pressure is generated by the pump ram with a ball check usually on the far end of the chamber.

The gauge on my 20-ton press is maxed out at 40K psi. That's when the relief opens. Working pressure is red lined at 30K but I've occasionally loaded it up to 40K on special occasions. 8.5Kpsi should not be much of a challenge even for Chinese jack power units.

Does the ram creep back under load? That would most likely be the check valve. I'm glad to share what I know with you.

I hope I've helped somewhat. Get back to me if you need more information. :cool:
Nov 17, 2017, 10:39 PM
love-horsepower

Baum Hydraulics in Omaha has about any seal made and they are cheap. 800-228-9222 or 9288
Nov 18, 2017, 12:54 AM
tonyfoale

Quote:

Originally Posted by love-horsepower

Baum Hydraulics in Omaha has about any seal made and they are cheap. 800-228-9222 or 9288

Thanks, I live on the other side of the pond and the cost of shipping small parts here is usually many times the value of the part.
For now I have no particular problem, it was just that I can rarely resist the temptation of improving stuff.
Nov 18, 2017, 07:54 AM
nhengineer

Quote:

Originally Posted by love-horsepower

Baum Hydraulics in Omaha has about any seal made and they are cheap. 800-228-9222 or 9288

I always thought Baum was just cylinders & pumps. Thanks for the lead. However, I see nothing there regarding service jacks which is what we were discussing.
Nov 18, 2017, 12:46 PM
tonyfoale

Quote:

Originally Posted by nhengineer

I'm curious what GOOGLE thinks a "big MF pipe wrench" is.

It thinks it is a pipe wrench, to me they have always been called Stillsons.

Quote:

Originally Posted by nhengineer

Does the ram creep back under load? That would most likely be the check valve. I'm glad to share what I know with you.

Maybe you misunderstood my original post. I have no problem with the main piston seal nor creep. Certainly not since I honed the cylinder. There was a leak from the ram wiper O-ring seal which made a mess because the jack is mounted upside down and so the whole of the reservoir oil and the header tank was acting on it. It couldn't have happened with a right way up jack.

Anyway I have now removed the outer cover and I feed and drain directly into a low mounted reservoir, so if anything leaks the maximum quantity is only the tiny amount in the O-ring groove above the O-ring, only a couple of ml at most. I'll make a separate post describing the current configuration.

Many thanks for your willingness to help.

BTW where do you live in NH? I lived there for 3 years, 2008-2010. I lived in New Boston and worked in Bedford.
Nov 19, 2017, 09:12 AM
tonyfoale

Just a word of warning to anyone messing with jacks or hydraulics in general.
DO NOT USE BRAKE OR CLUTCH HYDRAULIC FLUID. That stuff is different from real hydraulic oil.

You can get "Jack oil" from auto parts stores in the US. Around here it is not common and I use oil labelled for the hydraulic systems in Citroens. Probably the same as stuff labelled as jack oil? Power steering oil is probably similar.
Nov 20, 2017, 08:03 AM
nhengineer

Quote:

Originally Posted by tonyfoale

It thinks it is a pipe wrench, to me they have always been called Stillsons.

Maybe you misunderstood my original post. I have no problem with the main piston seal nor creep. Certainly not since I honed the cylinder. There was a leak from the ram wiper O-ring seal which made a mess because the jack is mounted upside down and so the whole of the reservoir oil and the header tank was acting on it. It couldn't have happened with a right way up jack.

That's telling me oil was leaking past the ram cup. I've been operating my 20-ton press for at least 30 years with an inverted bottle jack without losing a single drop of oil. Of course, it's not a Horrible Freight jack either. :lol:

Quote:

Originally Posted by tonyfoale

Anyway I have now removed the outer cover and I feed and drain directly into a low mounted reservoir, so if anything leaks the maximum quantity is only the tiny amount in the O-ring groove above the O-ring, only a couple of ml at most. I'll make a separate post describing the current configuration.

Many thanks for your willingness to help.

BTW where do you live in NH? I lived there for 3 years, 2008-2010. I lived in New Boston and worked in Bedford.

I'm in Franklin. New Boston is nice, very rural; no one around to bother you or stick their nose in your business.
Nov 20, 2017, 08:15 AM
nhengineer

Quote:

Originally Posted by tonyfoale

Just a word of warning to anyone messing with jacks or hydraulics in general.
DO NOT USE BRAKE OR CLUTCH HYDRAULIC FLUID. That stuff is different from real hydraulic oil.

You can get "Jack oil" from auto parts stores in the US. Around here it is not common and I use oil labelled for the hydraulic systems in Citroens. Probably the same as stuff labelled as jack oil? Power steering oil is probably similar.

I can't count the jacks I've rebuilt because the moronic owner used brake fluid instead of proper oil. In a pinch, you can use straight, non-detergent 30 weight (jack oil is actually 10 weight). I use ATF because it has no additives that will harm the seals and it can tolerate long periods of idleness. About the worse thing you can do to hydraulics after running them dry is to not use them at all.
Nov 20, 2017, 09:15 AM
tonyfoale

Quote:

Originally Posted by nhengineer

That's telling me oil was leaking past the ram cup.

One can not make that assumption based on the evidence.
If it was the ram cup that sprung a leak, the oil should have been kept in place by the O-ring wiper seal, which it wasn't.
On the other hand if the wiper seal leaked, which it did, then that alone gives no reason to suspect that the cup seal had leaked also, there was plenty of oil in the outer canister and my header tank to leak out without the cup seal leaking as well.

Yes New Boston is nice and I could make as much noise as I wanted. My house backed on to 500 acres of woods so plenty of trail riding and dog walking opportunity. The winters were too long and cold for my liking, my first winter there was the year of the famous ice storm. I assumed that it was normal winter weather there and I struggled into work to find only one other had made it in. It was only then that I realised that it was exceptional.
Still, I was sad to leave when my visa ran out, I liked living there.
Nov 20, 2017, 09:52 AM
Frank S

ON the machines that I used to build and my hydraulic elevators I mostly used Dextron II or Mercon ATF never type "F" because it had a formulation specifically designed for the way Ford designed their transmissions. up until sometime in th elate 80's or early 90's the materials in Ford transmissions required a special formulation or blend, not sure exactly why they did this but the practice was discontinued so far as I know, as my 93 350 uses Mercon
In NJ and NYC where my machines were mounted outside and could sit for hours overnight I found that for winter use they would be sluggish for the first hour of operation or until the oil in the 100 or so gallons in the tank and the 1000 ft of lines had made several circulations. Keeping the tanks warm only helped a little as there was as many as 50 cylinders and the lines that were cold soaked. My solution was to use transformer oil which is 5w, expensive but effective though it's lower lubricity could shorten the pump life.
For hydraulic jacks I use jack oil or clear power steering oil, if I have to use standard hydraulic oil I use the lighter duty and never the heavy duty rough service type as that has special blends to prevent thinning at high temps and is slightly thicker when cold. I have found some 5w non detergent motor oils in th epast that seemed to work just fine in jacks and port a power ram systems
Nov 20, 2017, 12:03 PM
nhengineer

Quote:

Originally Posted by tonyfoale

One can not make that assumption based on the evidence.
If it was the ram cup that sprung a leak, the oil should have been kept in place by the O-ring wiper seal, which it wasn't.
On the other hand if the wiper seal leaked, which it did, then that alone gives no reason to suspect that the cup seal had leaked also, there was plenty of oil in the outer canister and my header tank to leak out without the cup seal leaking as well.

Think about it Tony, the only way oil can get to the o-ring is to leak past the ram cup. The oil is supposed to only be on the high pressure side of the ram cup. The o-ring is just a dirt & debris wiper. It does nothing to seal the oil. If there is oil on the low pressure side of the cup there's something seriously wrong with it.

Quote:

Originally Posted by tonyfoale

Yes New Boston is nice and I could make as much noise as I wanted. My house backed on to 500 acres of woods so plenty of trail riding and dog walking opportunity. The winters were too long and cold for my liking, my first winter there was the year of the famous ice storm. I assumed that it was normal winter weather there and I struggled into work to find only one other had made it in. It was only then that I realised that it was exceptional. Still, I was sad to leave when my visa ran out, I liked living there.

Get a new visa and come on back or come in through Mexico like everyone else does.
Nov 20, 2017, 12:16 PM
tonyfoale

Quote:

Originally Posted by nhengineer

Think about it Tony, the only way oil can get to the o-ring is to leak past the ram cup. The oil is supposed to only be on the high pressure side of the ram cup. The o-ring is just a dirt & debris wiper. It does nothing to seal the oil. If there is oil on the low pressure side of the cup there's something seriously wrong with it.

No, no, no. The jack is upsidedown, The whole thing is full of oil.
Nov 20, 2017, 12:28 PM
nhengineer

Quote:

Originally Posted by tonyfoale

No, no, no. The jack is upsidedown, The whole thing is full of oil.

Ye, I understand. Mine is also upside-down but the oil stays on the pressure side (top) of the ram cup.
Nov 20, 2017, 01:15 PM
tonyfoale

Quote:

Originally Posted by nhengineer

Ye, I understand. Mine is also upside-down but the oil stays on the pressure side (top) of the ram cup.

Unless I misunderstand your earlier comments, yours is a proper stand alone hydraulic ram, in which case your comments were valid. However, I thought that it was clear that I was talking about an inverted bottle jack based press as I referenced in the top post. See here http://www.homemadetools.net/forum/i...5188#post81319

However, last night I made another separate post outlining my latest modifications which essentially convert a bottle jack to a simple single cylinder style of ram, albeit with an integral pump. So now there will be no leakage unless the cup seal leaks. If that happens there will be no mess because I have incorporated a drain.
See here: http://www.homemadetools.net/forum/m...op-press-64826
Nov 21, 2017, 07:46 PM
wizard69

If you guys are in need of seals for hydraulic or pneumatic cylinders, especially odd ones, try: Hydraulic cylinder repair seals and kits-Hercules Sealing Products - Hydraulic Seals and replacement cylinders for construction and many other heavy equipment industries.. Most of my rebuilding involved Parker glands and in that case we just ordered from Parker. In any event if you look around a bit you will find the raw materials for hydraulic cylinder building or rebuilding. there is a big market for custom built cylinders, often built by smaller companies, and they need to get their parts from somewhere.

As for seal replacement it is usually best to go with an exact replacement when possible on a piston. I've actually seen enough seal failures that are not wear related per say that I inspect each cylinder before considering a complete replacement. This is especially the case due to seals being subject to damage from improper installation of the piston.

Oh one more thing with respect to safety, DON'T TRUST ANY JACK, with body parts you want.
Nov 21, 2017, 07:56 PM
wizard69

The chat about oils is very interesting, you guys should be glad that you aren't working on hydraulics running on water/glycol. I spent a couple of years working in a die cast foundry and everything ran on water/glycol mainly due to safety concerns in event of a leak. Between the heat and the water/glycol I got really good at replacing shaft seals fast.

Now days I'm in an different industry and can count on seals holding up for years - what a relief.
Nov 22, 2017, 11:24 PM
Yaculls

Thanks for the post Tony.

I found it very interesting and you made a good point as to why you shouldn't put any part of your body under an object being held up by jacks.

It made me think about the guys I had replacing my stumps under my house they used a fare few bottle jacks during that operation.
Apr 19, 2018, 02:53 AM
Steved53

(QUOTE) It is never good practice to place any body parts under anything only supported by an hydraulic jack, and the findings here only serve to emphasize why. (QUOTE)

Or anything else supported only by hydraulics.... Or ropes... or chains... or jacks ... or etc etc. Stands or blocks every time.
Aug 9, 2018, 05:57 PM
bruce.desertrat

Well I knew what nhengineer meant by "a big MF pipe wrench", but google seems to think it's a combo open end/closed end wrench https://www.jensentools.com/images/p...01_s500_p1.jpg apparently because Proto has a -MF- in the model designation....
Aug 14, 2018, 10:23 AM
nhengineer

Most everyone knows what an "MF" is. :agree:
Dec 7, 2018, 06:48 AM
nhengineer

Quote:

Originally Posted by tonyfoale

A while back I detailed how I upended a bottle jack for use in a press.
See here http://www.homemadetools.net/forum/i...5188#post81319

"....It would have been much easier if I had unscrewed the cylinder from the base but it resisted all my efforts to do that. I was concerned that any increased effort would distort the cylinder...."

The cylinder is really screwed tight into the base. This trick was shown to me by a old bottle jack rebuilder (my dad). With the jack base securely locked in you best, floor mounted vice, put the ram and ram cup back in, almost all the way down to the bottom. Get you BIGGEST pipe wrench and slide a long pipe down the handle. Grab the cylinder as close to the location of the ram & cup as you can. Grit you teeth and unscrew the cylinder - it will usually give without collapsing.

When you're finished with whatever you need to do with the cylinder, reinstall it using the same procedure. If you try using a bench mounted vise, you'll drag the vice and bench all over the shop unless the bench is securely floor mounted.
Dec 7, 2018, 06:49 AM
69G T O

Quote:

Originally Posted by nhengineer

I'm curious what GOOGLE thinks a "big MF pipe wrench" is. Around here (central NH, USA) the "F" part is an expletive and the "M" part stands for mother. It looks like this Attachment 20494 only the handle is 48" long.

Here's the WEB page. https://www.whitecap.com/shop/wc/p/r...iABEgICk_D_BwE

Back 30 or so years ago I purchased my parts kits from The Jack Pack & Tool Company on N Marianna Ave, Los Angeles, CA. They are out of business - couldn't compete with $25 Chinese throwaways. Now, if it won't hold the weight, I put in a new ball check (from McMaster-Carr). The ram cup is usually not available but ram cups seldom are the problem anyway. The only other "seal" is the shaft wiper (and now-a-days that usually just a standard O-ring), the release needle valve housing and the pump ram (and they're usually just O-rings too). I've seen some jack rams with double or triple O-rings instead of a cup. That kind may NEVER give satisfactory results under max load after a bit of use and maybe not even when brand new.

Basically, if it won't hold the weight, it's the ball check and that's just a commercial steel ball bearing. If the ram cup is worn out, I trash the jack because, if it's worn out by spending its life in nice slippery hydraulic oil, it's seen a great deal of use and time to be retired. Same deal for the pump ram. The pressure is generated by the pump ram with a ball check usually on the far end of the chamber.

The gauge on my 20-ton press is maxed out at 40K psi. That's when the relief opens. Working pressure is red lined at 30K but I've occasionally loaded it up to 40K on special occasions. 8.5Kpsi should not be much of a challenge even for Chinese jack power units.

Does the ram creep back under load? That would most likely be the check valve. I'm glad to share what I know with you.

I hope I've helped somewhat. Get back to me if you need more information. :cool:

A lot of the time you can "clean up the seat" with a little TLC. The check ball is a hardened steel ball bearing and the seat is mild steel,so take a brass punch center it on top of the ball while it is on the seat and smack the punch with a big 'ol hammer.Then remove the ball and inspect if there is Any damage then trash the jack.If no damage put her back together and enjoy.
Dec 15, 2020, 10:47 PM
love-horsepower

You measure any seal o-ring backup washer square seal they will have it
Jan 8, 2021, 07:33 PM
nhengineer

Quote:

Originally Posted by 69G T O

A lot of the time you can "clean up the seat" with a little TLC. The check ball is a hardened steel ball bearing and the seat is mild steel,so take a brass punch center it on top of the ball while it is on the seat and smack the punch with a big 'ol hammer.Then remove the ball and inspect if there is Any damage then trash the jack.If no damage put her back together and enjoy.

Yup, that's what I do. Works slick.
Jan 17, 2024, 10:06 AM
Hans Pearson

I used a 12 tonne jack (inverted) in my hydraulic press. This means that under the full allowed load the pressure in the cylinder would be in the region of 11 200 psi. I changed the pump to an external pump with a slightly larger area and under test could only push about 6.5 tons which was still quite ample for normal use for me. Looking at jacks in general, the pump area on all jacks seems to remain constant, the piston size is changed to allow for higher loads, and subsequently longer pumping times/more strokes to achieve the same lift distance.
Jan 19, 2024, 09:39 AM
Hans Pearson

Tony, I have just been over my figures for my press pressure in my 12 tonne press. The piston diameter is 1.73" which gives an area of 2.35 Sq. In. 12 Metric tonnes is near enough 24300 lbs. Divide the area into that and it gives a slightly revised pressure of 10340 psi to obtain 12 tonne lift.
Jan 19, 2024, 01:07 PM
tonyfoale

Quote:

Originally Posted by Hans Pearson

Tony, I have just been over my figures for my press pressure in my 12 tonne press. The piston diameter is 1.73" which gives an area of 2.35 Sq. In. 12 Metric tonnes is near enough 24300 lbs. Divide the area into that and it gives a slightly revised pressure of 10340 psi to obtain 12 tonne lift.

Hans, You must have seen a post that I made which I deleted the contents of, and which is not being shown now. I apologise. I made an error and as soon as I realised it I went and deleted the contents hoping that nobody had seen it. Your numbers are fine, mine were not.