Well, I’ve now done this twice and I never published the pictures I took the first time, so here goes. 

What you may notice is the resistance is always higher than what you want…or what you remember the least resistance to be.  In fact, at one point, you might have heard the "pop" or "snap" while using your elliptical and notice the resistance no longer adjusts as low as it should.  You’ve come to the right place, and I’ll show you how to repair this for $10 or so.

So what is an "Eddy Current Brake?"  Well, it’s the magnetic part that creates the adjustable resistance on your machine.  In particular, we’re talking about the FB1 manufactured by Chi Hua in Taiwan.  To break (brake…LOL) it down in simple terms, eddy currents are created from the magnetic flux (of magnets) passing through a coil of wire (conductor).  Basically, you have a generator that creates small currents in a conductor that are essentially short circuited and turned into heat.  You can read about it at the source of all knowledge…Wikipedia.  This is what makes the drag force on your elliptical…you know, the thing that makes your legs hurt and sweat pour from your body.  Check it out on their web site and use your web browser’s translate feature.

Well, here’s what happens.  The blue actuator pulls and releases the cable based on the level setting.  This makes the white part in the green ECB (Eddy Current Brake) travel back and forth, which moves the magnets away from and closer to the flywheel, generating your resistance.

Unfortunately, after some period of time, the cable wears and snaps in two.  This is shown after removing the green part (essentially the stator). 

Getting the green part (stator) out (assuming yours is green, too) requires some mechanical work, but it’s not too hard…just takes some time.  You have to remove the flywheel.  Release the tension on the belt by loosening the nut on the tensioner.  Then you have to remove the flywheel nuts and the tensioner bracket.

You also have to remove the stator locking bracket to get it out of the way.  The actuator cable is easier to remove from the blue actuator side first by pulling and unwrapping it from the nylon spool.

What you are going to have to do is fashion a new cable to replace at least the one that broke.  Maybe two, if the other is worn and fraying.  I did this by purchasing a bicycle shifter cable ($5) and grinding down the barrel end with my Dremel tool to make it the correct diameter and length.  The ball end of the cable is not very critical.  It simply needs to NOT pass through the hole in the magnet.  You can pass the barrel end through the hole when threading it in place.  The replacement for the ball is a cable clamp that has been "swaged" in place using a crimping tool.  I used my ratcheting electrical crimpers, but you may want to opt for something more professional, like these hydraulic crimpers.

Here are my notes I took with my calipers.  Notice the leftover Christmas notepad paper. 

I didn’t get any pics of the stator taken apart, but it’s pretty easy to remove.  Two allen set screws hold it to the shaft.  Loosen these and pull it out…you’ll feel the magnets wanting to keep it in the flywheel.  Then there are some black phillip screws holding it together and the four silver screws that hold the thingamajiggy with the allen set screws.  Inside you’ll see the white plastic actuator that connects all the cables.

When you are done you’ll have something that looks like this.  Not really pretty, but very functional.

Yes, we have a slide…and a diving board…on our pool.  OMG!  Now that we’ve established that and the fact that we are not going to remove them, here’s my latest upgrade.

The slide is about 15 years old and empties into our salt water pool.  The original plumbing on it is in the form of 1/4" tubing attached to recirculating water coming from the pool pump.  However, it’s never worked very well because of the pressure drop from the 3/4" PVC to the 1/4" flexible tubing with which the slide is plumbed.  In fact, at one time, I added a spigot from our irrigation system which worked pretty well, but the primary problem remained.

The primary problem is the 1/4" tubing never seems to last more than one season.  We’re in Texas and it’s hot!  Between the heat and the (somewhat) cold (yes, it does freeze at times), the tubing becomes fragile and breaks, necessitating its replacement every season.  So, when the kids are over and it’s broken, a hose gets dragged to the slide and tied to and draped over a handle.  Not cool.  Plus, whether it’s the hose or the spigot, it’s up to me to turn off the fresh water supply, since no one ever seems to be able to do that when they are done.

My goal was to reduce the pressure loss by using a larger main line up and down most of the length of the slide.  You can see my attachment of 1/2" PVC to the 3/4" PVC main line.  After the reduction fitting, I used a removable PVC union fitting so the entire extension can be easily detached and removed, if necessary.

Under the slide I provided a cutoff valve so it can be easily turned on and off at the slide.  There is also a master Jandy valve located at the pool equipment.

I was originally going to plumb it with 1/2" flexible PVC, but it seemed to be a bit difficult to get 11 feet of it without purchasing a 50 foot role.  Home Depot and Lowes don’t stock the small stuff.  So I finally decided to use rigid 1/2" PVC.  In order to make it contour to the slide, I used my heat gun and patiently heated it up until it was flexible enough to form into the correct arcs.

Probably the neatest thing I did was take a PVC cap and drill and tap a hole that would accept one of those quick connect 1/4" tubing bulkhead connectors.  I used plenty of Teflon tape on the threads and screwed it into the end of the modified PVC cap.  This provides me with a quick way to make a short 1/4" tubing connection from the 1/2" PVC to the 1/4" slide fitting.

I did this at both the bottom and top, leaving enough room so the 1/4" tubing has room to flex and bend.  On the bottom, I replaced the bulkhead connection on the slide (since it broke) with another 1/4" tubing quick connect, so replacing this short piece of tubing literally takes about 30 seconds.  The lower slide nozzle correctly screws on the end of this quick connect bulkhead fitting.

Here’s the top.  The tubing is a bit longer, but still quick and easy to replace.

An underside look at the top.

Next, I replaced all the hardware with stainless steel hardware.  I ended up having to cut some of the bolts because the salt had corroded them so badly.  My hardware was ordered from Albany County Fasteners on the web.  Love these guys and their stainless hardware.  Shipping is free with a $25 order!  Or you can purchase stuff from them on eBay.  Here you can see the carriage bolts replaced with stainless.

This is essentially a stainless lag screw replacement.  I had to go a bit bigger because the aluminum rail was stripped, probably during the initial installation.

I had an issue with the aluminum handles being loose.  Problem was the aluminum attachment block in the handle appears to be held in place with epoxy of some kind that had lost its grip.  I re-engineered it with a through hole and stainless hardware. 

I also had to drill and tap out the broken screw that comes up from the bottom of the slide.  When I attempted to remove these screws that hold the handles in place, they promptly broke.  In fact one was broken already which was the cause of one of the handles being loose (very unsafe).  Not surprising, they were completely rusted.  These screws fit into the bottom of the aluminum block that extends from the handles.  They are not going anywhere now!

The complete project was probably around $50 in hardware and supplies and the results were great.  There is now plenty of water that recirculates through the pool and on to the slide with significantly less pressure drop.  It used to dribble…now it sprays!

If you’re like me and have a pair of these fairly expensive ($60-$80) Logitech headphones, model H760, you might find their weakness is in the plastic that is part of the headband that connects the headphones together.  Many people have issues with the plastic breaking, rendering them useless.  If you contact Logitech and have a receipt, they’ll probably replace them for you because they’ve had so many complaints. 

I couldn’t find my receipt so I "fixed" them using some tie wraps as shown.  There was enough left of the plastic this seems to be holding.  If you don’t have one of these tie wrap guns, I’d suggest you get one for all the "rigging" you do around your home.

My wife purchased one of these Litter Maid covers (i.e. Cat Privacy Tent…ha, ha) because one of our newly acquired cats has some messy restroom habits.  These habits cause my wife to have to clean all around the electronic litter box, which she despises.  So, she purchased one of these and began to put it together.  Well, needless to say, it’s not engineered very well or very sturdy. 

The original frame is constructed of flimsy 1/2” outside diameter plastic tubing.  There are numerous connectors that allow you to connect all the pieces like Tinker Toys.  Bad part is, after putting it together, it is almost impossible to zip the top and bottom halves of the cover together.  It appears to be 1/2” – 3/4” too tall.  Seems like it was made to be more like a convertible top, where you have to really stretch the material (plastic) to join it.  This ain’t something that most mere mortals will be able to do without a heat gun or something to really soften the cover material so it will stretch easily.  Plus, while attempting to zip it together, my wife busted one of the 3-way connectors.  That makes it pretty worthless.

The original frame size is about 28” x 19” x 19”.  The new design uses 1/2” schedule 40 PVC and is resized as 27-3/4” L x 18-3/4” W x 18-1/4” H.  You can see my notations on the original instructions.  A typical PVC connector has a 3/4” receptacle and increases the overall length by 1” when the pipe is buried into the receptacle its full 3/4” depth.  Since I couldn’t find 3-way connectors with all slip connections, I had to use 3-way connectors with 2 slip and 1 threaded connection.  This meant that I used adapters for the vertical sections, which took another 1” (x 2) off the length pipe needed.  That’s where the 18-1/4” – 2 – 2 = 14-1/4” calculation comes from (subtracting 2” from each side to allow for the connectors).

If you’ve never worked with PVC before, all I can tell you is to make sure you have things lined up because the PVC cement sets fast.  I built the long top and bottom pieces first, then screwed the adapters into the corners and finally joined the top and bottom together.  Not hard, but if you screw up, you might be starting over!

Putting it together ends up looking like this.

After installing the bottom part of the cover.

Here’s the top and bottom covers placed on the new frame.  Testing out the operation of the Velcro tabs.

Here’s what it looks like closed.

Placing the Litter Maid in the frame with the lower cover installed.

And finally, the top cover in place and the whole thing put back in its place.  Fits purrrrrrr-fectly!

I have a Sentry Safe that I purchased from Sam’s a year or two ago (too lazy to look it up).  My wife recently tried to open it and, even though it agreed with the combination that was entered, the electronic opener refused to release the lock.  Since this safe can only be opened with an electronic code, this is a BAD situation!

I first tested all four batteries with my handy-dandy battery tester and they all passed with flying colors.  I could hear the actuator trying to work each time I entered the code.  I even tried the “master” code.  No go.  Being somewhat mechanically inclined, I decided to whack on the front of the safe with my fist (didn’t think I would hurt it) after entering the code.  Viola!  The actuator fired up and it opened.

I then started looking on the web and found this post by lighthouse.  Exactly my problem!  All you need is a Rubber Mallet (or a hard fist), some WD-40 and a screwdriver. 

Needless to say, I’ll be taking it back to Sam’s and getting my money back, regardless of whether it’s in or out of warranty.  I think Sentry Safe has sold many of us a bill of goods…what do you think?  POS!

2010-07-10 Update

So my son purchased a Sentry safe today and I warned him about the sticking problem.  Since I never did anything about my safe since I opened it last, I decided to pry the plastic cover off so I could see the innards and determine what to lube.  Looks like the actuator in the upper left is the source of the problem.  So, if you need to whack your safe, you can see that the upper right (as you’re facing it) would be the place to smack.

When I pried the back off, there was all kinds of plastic slag and crap sitting at the bottom on the ledge.  Such quality…

One of the comments to lighthouse’s post was by a guy who used his “saws-all” to cut through the pins.  As you can see, these are all just cast parts, which means they are probably very soft metal.  I guess if this safe is ever involved in a fire it will open automatically as all the parts melt!

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