Shoebox F10 rebuild?

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cahil_2 said:
Just keep running it. With mine it just wouldn’t pump higher than 2000 if my memory is correct When it needed to be resealed. Mine was over lubed.
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Thanks. Happen to remember how many hours you got before it got to that point (max of 2000)?

Mine's still running good, and filling at the same rate it always has (100fps increase in the 87cf tank for every 10 minutes it runs). And topped off to 4500 yesterday. Recently adjusted the cut-off to 4500 instead of the previous 4250ish.
 
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When mine reached 100 hours, I rebuilt it. Very easy and there are good you tubes from Tom to help if needed.
While I started off adjusting the pressure to 4500PSI, I figured that made the machine work that much harder against greater pressure, so I backed it down to the factory setting of 4250ish. Yeah, I don't get quite as many top offs, but if the Shoebox lasts longer, I'm good with that.
I'm assuming that you have a rebuild 'kit', but if not, I have the O-ring sizes and durometer information if you need it. I also had the burst disk blow in the past year and a half, so I bought 6 from Amazon for a good price. I made that an easier install/fix by drilling a 1" hole in the back of the red outside casing directly in line with the disk to gain access without taking the entire aluminum 'tower' apart. I worked great.
Over-lubing is easy to do, it only takes a minor amount of silicon oil on the felts to do the job. Too much is shortening the life of the system. More is not better.

mike
 
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Revoman said:
When mine reached 100 hours, I rebuilt it. Very easy and there are good you tubes from Tom to help if needed.
While I started off adjusting the pressure to 4500PSI, I figured that made the machine work that much harder against greater pressure, so I backed it down to the factory setting of 4250ish. Yeah, I don't get quite as many top offs, but if the Shoebox lasts longer, I'm good with that.
I'm assuming that you have a rebuild 'kit', but if not, I have the O-ring sizes and durometer information if you need it. I also had the burst disk blow in the past year and a half, so I bought 6 from Amazon for a good price. I made that an easier install/fix by drilling a 1" hole in the back of the red outside casing directly in line with the disk to gain access without taking the entire aluminum 'tower' apart. I worked great.
Over-lubing is easy to do, it only takes a minor amount of silicon oil on the felts to do the job. Too much is shortening the life of the system. More is not better.

mike
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Thank you Mike.
I do have rebuild kit(s). Seems like I paid for some extras when I bought the F10 but Tom also threw in a couple more. I should be good on orings for awhile if each set goes as long as the originals have.

I like your idea for accessing the burst disk-may have to do the same if it becomes something that needs replaced.

I only give it a drop of silicone on the felts every 4 or 5 times that I run it. And average run time is probably about 90 minutes. In the beginning (first 5 or so hrs) I was overlubing as well, evidenced by getting some silicone on the filter media in my output filter. I remedied my ways and those filters don't see the lube anymore. I also do white lithium grease on the rods, but only on the right side of the aluminum bar that supports them.

Again, thanks for your insight.
Cole
 
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Glad that you (and Tom) had the foresight to nab some extra kits. I too use the white lithium grease on the pistons, only on the right side of the bushings/bar.
Drilling that hole makes that particular repair super easy without dismantling the tower. A deep socket with a ratchet is all that is needed.
I always keep my fingers crossed that the Shoebox will last for a long time. It absolutely suits my need to a tee.
mike
 
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Old Spook --=-- I agree, but apparently the Chinese compressor competition was too great to overcome and they quit.
I would recommend actually talking with Zack as it seems that there are SOME parts not shown on the website, yet attainable per some of the banter on this forum. Zack is super friendly, helpful and knowledgeable. At the very least, there is a chance that Zack will know where to procure some of the parts needed.
mike
 
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Well I don't know if it was Murphy's law or I didn't knock on wood after posting this two weeks ago, but a few days ago the ole trusty F10 wouldn't fill past about 2900psi.

Tom Kaye's old repair vids are still on YouTube and new orings seemed like a pretty easy task. Got it apart to find the delrin spacers on the lower cylinder were toast, melted and deformed. Replaced the orings and spacers and cranked it up. Got to 4200psi and then it blew a fuse. Replaced fuse and investigated to see why it had blown. Found the newly replaced delrin spacer and the felt had become one, melted into a ball. It seemed like the felt had started into the cylinder and got tight and then got hot, really hot. I had relubed the felt with silicone at the rebuild 20 minutes earlier. Silicone is all I had every used up to this point, all 93 trouble-free hours.

So, got it back together with new plastic spacers, no felt, and white lithium on the orings in the cylinders. This was on a friend's recommendation. He owned a much earlier version Shoebox years ago and used white lithium for many hours without any problems.

Cranked it on, pressure building like it should, and the internal tooth/push on locking washers popped off the crank arm linkage!?!?! While I was standing there. Never had this problem before. Got the locking washer back on, let it build pressure again and all seemed well. Stepped away for a literal 5 minutes and came back to hearing all kinds of commotion, right as it threw the gfci on the outlet. Lock washers had popped off again, thrown the linkage a few feet away, and bent the support bar that both rods go through, on the right side of the unit.

Got it apart again, removed and carefully bent the support rod back to straight. Luckily it is round and I could roll it to verify straightness.

Put it back together and turned it on again (5th or 6th time's a charm right?) and now the bushing that the rod for the upper cylinder rides in on that right support bar is popping out after a few revolutions and getting smashed between the bar with the set screws that holds both rods, and the right support bar. And, to add insult to injury, pressure wouldn't go past a couple hundred psi.

So, at that point yesterday I'd worked on it far too many hrs and got disgusted and shut the door on the gun room and walked away from it.

I kinda feel like I'm now paying for all the trouble-free hrs I've gotten out of this little unit. Also feel like I was playing whackamole with all the problems yesterday.

The rods are both straight as an arrow, so a bent rod doesn't seem to be the source of all the frustration.

I'm not sure I've ever lost as much faith in something so quickly as I have with the F10 in the last 24hrs. I'm not even sure where to go with it from here. I guess I'll take it apart again and see if I can figure out what the deal is. The most immediate problem seems to be that bushing that won't stay put. But even if I resolve that, I've still got the not building pressure issue, and the cranking arm linkage wanting to pop off.

Sigh
 
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A few of things:
1.) When reassembled, did you reset the depth of the pistons to not hit the check valves?
2.) Did you replace the O-Rings on the check valves?
3.) Did you clean the check valves, that is where a lot of any extra silicone from the felts end up, causing issues.
4.) When you removed the pistons to replace the spacers, are you sure that everything is properly aligned? I usually reassemble, then hand turn the crank to be sure that there is no/little resistance before going further and tightening everything done. I believe that Tom recommends marking the machines shell with an awl to assure proper placement.
White lithium grease is the right stuff to use on the pistons.
I have never experienced the melting of the plastic spacers, it seems that it is getting much too hot. So, if the pistons aren't correctly aligned and off kilter, that would show the heat reason. It also might explain the bushing issue too.
Over lubricating the felts is something that is easy to do, yet detrimental to the innards as you described (guess how I know?).
Just a few suggestions that may help, I hope.
mike
 
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1. Yes, another of Tom's old YouTube videos show d this.
2. Yes
3. Yes
4. No, I'm not sure but I did as you suggested, and didn't completely tighten the bolts through the the top and bottom of the shell that hold the right support, until I had trying ned the crank by hand to ensure no binding.

What I don't get is that the original delrin spacers had melted before I ever removed the rods. For the first two of the many tear downs yesterday, the rods were still in the position they were set at by Tom and have been in the whole time I've owned it.

For the previous handful of fills before these troubles, I was finding tiny bits of hard plastic inside the bottom of the shell. I now know there were melted bits of rod spacer, but still don't know what changed to have caused them to start doing this, cuz again, I'd never taken the F10 apart before yesterday.

Thanks for your suggestions Mike. I'm open to any and all right now. Maybe I'll revisit it with fresh eyes here in a bit.
 
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I feel your pain as I too have had irregular moments like you describe. Given it a rest and tried the following day only to rebuild exactly as I did the day before and have it magically work, Gremlins?
It just seems to me that since your spacers and the brass bushing at the round tower have gone haywire, that is the issue, not aligned exactly. Tom actually stresses alignment in one of his videos. Or perhaps the plastic spacers were so old and heat stressed that the simply gave up by crumbling, guessing?
You can get many parts for the Shoebox from OCO Labs (Zack). I see that those bushings are about $3.00, plus shipping from them.

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I tried to buy some of the hardened pistons, but they are NOT the same length, so hadda return (without issue) them to Zack. Not sure that Tom doesn't work for this place. I have had some luck buying parts through Grainger as well. I believe that Tom used Grainger parts for much of the parts in the Box.
I have rebuilt my F-10 at least 4 times after having it for about 11 years. I keep track of the hours and when it gets close to 100, just rebuild again without waiting for failure. 100 hours for me at least is in the 2-2.25 year range as I'm just topping off my large tanks from ± 3500PSI to 4300PSI. I dropped my shut-off from 4500PSI to 4300PSI to prevent making the machine work harder, yet still give me enough air until my next need.
Fresh eyes carry a lotta weight by the way!
mike
 
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