Sunday, March 20, 2005

$4 Carbonator

Products like The Carbonator look like a great idea until you see the price tag. The link back there is the cheapest I have seen. The local homebrew shops in my area want $15 for it. In the end it's only a plastic cap with a check valve and disconnect. It's also something who's function you can reproduce for under $4, under a dollar if you don't want the check valve function.

This hack works a lot like the Vacuum Beer Bleeder below with one modification for managing the extra pressure.

Again you are going to need a few fittings:

I know that adds up to more then $4, you will only one of the instant hose fittings. If you haven't see these before the are kinda like ad external hose barb. There is an o-ring inside to seal around the tubing and some little barbs to grab the outside of the tubing. The really cool part is you press on the front of the fitting and it releases the tubing. Kind of like a simple quick disconnect, but you don't need a fitting on the tubing. As for the check valve you only need this if you want to carbonate something and store/transport it. If you only want to quickly carbonate something like a beer sample or water you won't needed the check valve. So you could do this for just over $1 a cap.

So to get things started. You will need to drill a 3/16" hole in the center of the cap. Next thread in one of the hose barbs making sure to include the little gasket they give you. Now to make sure the hose barb stays in place thread a coupling onto the end of the hose bard now sticking thru the inside of the cap. Tighten this being careful not to strip it. Now just add some hose and the check valve if you desire. Use the instant fitting to make the connection to your CO2 regulator.

I find that 30psi and about 1min of violent shaking will carbonate any cold (40F or lower) liquid. Let it sit for another minute still under pressure before you remove the cap. I mostly use this for making soda water and carbonating beer samples.

Note: You could use a regular #10-32 nut in place of the coupler just make sure it is brass or stainless.

Vacuum Beer Bleeder

I've spent a lot of time thinking about a good way to take samples for beer in progress to check gravity. I bought a 50ml volumetric pipette but it was quite slow to fill and took 2 cycles to get the 100ml I needed to float the hydrometer. I have looked at devices like the wine thief and didn't feel like spending money on something I felt should be very cheap also it was more then I wanted to sanitize every time.

The result of this is the Vacuum Beer Bleeder for about $2 in materials, an empty soda bottle and cap you to can make the greatest breakthrough in beer sampling technology!

It goes like this you need 2 1/8" x 10-32 hose barbs (McMaster Carr 5454K62) and about 3' of 1/8" ID tubing. Now drill two holes in the plastic bottle cap just small enough to force thread the fittings into, if you want to get fancy break out the tap set. Keep in mind that these holes need to be close enough together that you can still thread the cap on. Now screw in two hose barbs and shove some tubing on. I like to cut one tube short just so I know which one to stick in my month.

When you need to sample just stick this cap assembly in sanitizer, drain and screw on an empty soda bottle. Now stick the long hose in the beer and the short on in you mouth and suck until you have drawn what you want.

Here are some images of the finished product....

Simple brew kettle heat sheild

This could easily fall into the catagory of too simple to mention but who knows....

Yesterday was a great day with temps int he high 50's and sun. So i decided to do my first outside brew session. The only problem it was a bit windy and i could stant sitting there feelign like all the heat was exiting my kettle thru the exposed sides. No to mention all the wasted heat blowing off the burner. Luckly I had some aluminum flashing laying around. 2 minutes worth of work and i had a cylinder held together with binder clips that fit nicely inside the frame of my $30 Thermos turkey fryer burner (the kettler came with this kit from Target, great deal of the year).

Now i had a way to carry all the waste heat from the burner up around the side of the kettle, not only should this prevent cooling of the kettle but should also push a little more heat into the kettle. I don't have any data to back you this efficeny increase but quick readings at the top of the jacket showed the air between the kettle and heat sheild was 215F-230F.

Friday, January 28, 2005

BMW 6 Series Brake Accumulator Replacment

Having brake problems? When you hit the pedal hard and fast--like a panic stop--and the pedal is hard and lacking power for a second and then the assist kicks in? You need a new accumulator, a.k.a. "bomb". It's a simple replacement, this how-to should give you all the info you need. In convenient PDF format.

BMW 6 Series Stereo Installation

Note: This is for the original 6 series. Not that monstrosity BMW is selling now.

I have never experienced the factory radio in a six but I can't imagine it has much to offer. As for replacing it the hole is a standard single DIN, the wiring is nothing close to standard. The factory amp was 2 channel and I bet yours is 4 channel, right? Well here are my suggestions for pulling of a clean installation. In convenient PDF format.

Thursday, January 27, 2005

NRP Station Guide for iPod

I love my iPod but I also love NPR particularly the news coverage when I'm driving. So the problem I have is finding the stations as I drive across and thru various states. So a half hour of Excel and a lot of cut and paste and I now have the complete NPR Station Guide on my iPod using the quite useful note reader. I suspect there may be a few other people interested in this so here it is. Just unzip the folder and place it in the notes folder on your iPod. The stations are divided by state for easy browsing. I have removed the text extension from the end for cosmetic reasons but they are simply text files if you feel the need to edit them.

Wednesday, January 26, 2005

Fox Vanilla RC O-rings for sale

If you read below you can see I know what it's like to need a small part like an o-ring and have to buy a bag of 50. So I guess I can share with everyone else.

If you need a 2mm x 27mm ID o-ring for your Fox Vanilla RC repair
contact me and I'll be happy to get you one for a modest fee. Say you send me a SASE with $1 in it?

How to change the oil in a Fox Vanilla RC shock

About a month ago my Fox Vanilla RC fell apart. I was on a ride and noticed something that sounded like a loose pivot in the rear suspension it turned out it was not a pivot but the shock cylinder had started to unscrew from the shock body and all of the oil had leaked out. I had been looking for a reason to get a new rear shock but I didn’t want to do it till the spring. I looked into having someone like PUSH Ind. refill it but it turns out they won’t refill a shock unless they have rebuilt it in the past. Looking at spending $90 on a shock wanted to get rid of wasn’t appealing. So I figured I would take a crack at refilling it myself, how hard could it be right? Turns out not too hard at all. A good bit of searching showed no tips for doing this. So after successfully working on my shock I figured I would write this up for the better good.

Fox says you should never take you’re shock apart. It will void the warranty and you could break it. If you are don’t regularly work on your bike and wouldn’t consider working on your fork walk away now. If you work on you shock and it breaks in the future or blows up on a big landing hucking you into traffic I am not responsible. If you have reservations about anything buy a new shock or send it to someone carrying liability insurance like PUSH.

When I disassembled my shock I found that the o-ring that seals the cylinder to the shock body had been damaged likely during the small about of ridding before I noticed the shock was falling apart. Again no one sells parts for this shock as you’re not supposed to take it apart. So some measuring of the old o-ring and related parts lead me to the replacement being a 27mm ID x 2mm wide Buna-N o-ring available from many places including
McMaster Carr (pn 9262K193).

Beyond the o-ring all you should need is 5wt. shock oil and assorted hand tool. Latex gloves can be nice as there will be oil all over your hands.

Hydraulic system warning:
A shock is a sealed hydraulic system. There is noting you want less then dirt in a hydraulic system. Cleanliness is paramount here. Before you take anything apart (but after you remove the spring) clean the entire shock. Use a tooth brush to get in the threads on the shock body. Make the think look like new. As you are working use clean towels. If you are going to wipe any internal parts do it with a new paper towel that you know is clean.

Start by removing the compression adjuster. To do this first remove the two set screws one on either side of the compression adjuster. One of these has a spring and ball under that provides the clicks when you turn the adjuster. The other set screw is longer and stops the adjuster from unscrewing completely from the shock body. Don't worry about witch side these came out of as they can go back in either side.

After the set screws are out you can remove the compression adjuster. Just turn until it comes out. There should be an o-ring on the adjuster and a small spring and metal cup on the bottom of the adjuster. Don't lose these pieces.

You don't need to worry about an explosion or anything from the nitrogen charged reservoir or ‘losing’ your charge. There is a floating piston in the reservoir that separates the gas from the oil. This will keep all the gas in unless there is a leak around that piston. Then you have bigger problems then we can deal with here.

After you have the adjuster out you can drain the oil from the shock by holding it rod up, reservoir down and stroking the shock. Make sure you turn the rebound adjuster all the way out (faster) it will make it easier to stroke the shock. Once you have all the oil out it's time to take stuff apart!

First you need to remove the cylinder body from the shock base. The cylinder simply threads into the base with the same threads that the preload adjuster runs on. To remove it use a large crescent wrench on the flats at the end near the rod seal or a strap wrench on the cylinder. You should have a pan ready to catch any remaining oil that comes out.

Completely unthread the cylinder and drain the last of the oil completely. This can be done by stroking the piston while holding the cylinder upside down over.

Once you have all the oil out you can go about replacing the cylinder-base o-ring if you need to.

Now it's time to refill the shock. I'm not sure what weight oil Fox uses but I refilled with 5wt and it feels the same as factory. Start with the rod fully extended. Then fill the cylinder about half full with oil. Now slowly push the piston up until there is about 5mm of oil left on top of the piston, there should be bubbling as you do this. Now pull the rod back down, again more bubble. Add oil as need the goal is not to suck any air behind the piston and to get all the air out that is there already. Repeat this until you are confident that all the air is out. Pull the rod all the way out (piston to the bottom/shock extended) and fill the cylinder up to the top.

Next thread the cylinder into the body and tighten by hand. No need to really crank on it now the o-ring will keep things sealed.

Now we need to bleed the last bit of air out. The important thing to know here is that as you compress the shock the available space in the cylinder for oil will decrease. The oil will pass thru the main compression porting to the space behind the piston but that space now contains the piston rod which takes up space. This is why there is the piggy back reservoir with the floating piston. The oil displaced by the rod will flow into this reservoir and compress the nitrogen. This compressed nitrogen is why the shock will rebound slowly even without a spring on it. The nitrogen pushes the oil back into the cylinder.

We can use this rod displacement to our advantage when bleeding the cylinder. If you push the rod in with the shock at about 45 degrees and the open compression adjuster hole up, the air will flow out. Slowly push the rod in until you see oil come up thru the adjuster hole and get near the top of the hole. If no oil comes out it is OK just keep going. Now use a dropper bottle or syringe to keep the adjuster hole filled with oil as you extend the shock by pulling the rod back out. The oil should be sucked back into the cylinder. Repeat this procedure until you get all the air out of the shock and have to rod fully extended.

To reinstall the compression adjuster, fill the adjuster hole to the top (actually to the set screw holes) with oil. This will insure any remaining air is pushed out. Getting the adjuster back in with the spring and the cap on it can be a pain. The oil will hold the spring on but that little cap just wants to fall off. You can use a very small dab of clean grease to hold it in place. I don't think this should cause any big problems when it mixes with the oil. Another option if you don't want to use grease is to suck most of the oil out of the hole and carefully place the cap in the bottom of the hole with the hole side out. Then refill with oil and install the adjuster.

Turn the adjuster about half way to seal things up and use a wrench to tighten the cylinder to the body.

Now cycle the shock. Is should feel smooth and quite. If there is still air in the cylinder you will hear it hiss thru the porting. You will need to remove the compression adjuster and bleed the cylinder some more.

Congratulations you have just saved yourself some money and got to see the innards of you shock. Remember you can now also tweak the oil weight if you desire more of less damping then you can achieve with the standard adjusters or habitually ride in very cold weather.

Final Note:
It may be possible to do all this thru the compression adjuster hole and never remove the cylinder. The problem will be in filling the shock. The best way I can think of would be to use a syringe with about a 3 inch needle on the end, a Teflon needle would be ideal. If you insert this thru the compression adjuster hole and up the small hole that leads to the cylinder cavity you should be able to push oil in while still leaving a passage for the air to escape from.