supereasy DIY rear rack
NOTE: Before building this rack, scroll down and read the postscript.
So you want a rear rack for your bike - or any kind of rack for that matter - but you don't have the tools to weld or braze or whatever. Well never fear, comrades, J-B Weld is your friend!
Before we get into the actual rack stuff, let me just introduce you to J-B Weld properly, in the words of their own website: "My pickup threw a rod and tore a hole in the block. I plugged the hole with large washers bolted together and sealed it with J-B WELD. That was over 50,000 miles ago; still with no loss of oil. Thanks for a remarkable product!" There are hundreds of awesome testimonials like that, but not all of them are as sublimely redneck!
So here is what we need to build a rack, and it is all available at your local Autozone or other auto parts store. You want 1 package of J-B Weld, and 2 lengths of 3/8" rigid steel high pressure line. This is the stuff you can use for brakes, power steering, etc. It is soft steel so it is bendable. You might also want to pick up a tubing bender for this, and a tubing cutter if you don't have one. You will also need a round "rat tail" file, and auto parts stores usually have pretty good deals on tools, so why not get one there too.
The first thing you want to do is cut the two main pieces of the rack that will go from the seatstay rack eyelets to the dropout eyelets. Crimp one end of each. I used a bench vise, but a hammer would work. So would vise grips if you are truly desperate or one of those sickos that enjoy using vise grips.
Once you have a nice crimped section, drill a hole in it to accept a standard M5 allen head bolt. You don't want a lot of play here, so try to use a bit that is just barely bigger than the bolt. I think I used whatever size is just smaller than 1/4".
Now bolt that sumbitch to the seatstay eyelet. You will have a long straight piece of tubing to work with at this point. Begin bending it to the shape you want the rack to be. Note: A milk crate is about 13" square. Use a tubing bender or some sort of v shaped round thing, like a swamp cooler belt pulley, to keep the tubing from kinking. You will see an example of kinking later in this article. Try not to do that if you can.
My goal was to get the rack level, and leave about as much clearance between the rack and the tire as there is between the brake bridge and the tire. Since you left the tubing long, you can get it where you want it than mark it for cutting, crimping, and drilling for the dropout eyelet.
Once you have the two main pieces done, you can make the little struts that join them and for the platform for the rack. Just cut 3 (or 2 or 4 or whatever) pieces the same length, and use your round file to "fishmouth" them so that they form a nice fit with the main rails. Remember that your file will stay sharp much longer if you only drag it across the metal in the cutting direction, never backwards.
It is now time to mix up a batch of J-B Weld! Awright! Just mix equal parts of the steel and the hardener. I like to use a nail or something else disposable so you don't have to clean it.
Spread J-B Weld on the end of the tubing, put the pieces where you want them, and use bungee cords to hold it all in place.
Next go back and make "fillets" with more J-B Weld. This is easier that it first appears because J-B Weld has a cool surface tension property that makes it self-smoothing. Just get it to stick where you want it, and it will slowly pull itself to a smooth finish.
Let it harden overnight, remove the bungee cords and you have yourself a rack. Paint it so it won't rust, and you are ready to roll.
POSTSCRIPT: This rack broke almost immediately. It turns out J-B weld is not as cool as I thought it was :(
So you want a rear rack for your bike - or any kind of rack for that matter - but you don't have the tools to weld or braze or whatever. Well never fear, comrades, J-B Weld is your friend!
Before we get into the actual rack stuff, let me just introduce you to J-B Weld properly, in the words of their own website: "My pickup threw a rod and tore a hole in the block. I plugged the hole with large washers bolted together and sealed it with J-B WELD. That was over 50,000 miles ago; still with no loss of oil. Thanks for a remarkable product!" There are hundreds of awesome testimonials like that, but not all of them are as sublimely redneck!
So here is what we need to build a rack, and it is all available at your local Autozone or other auto parts store. You want 1 package of J-B Weld, and 2 lengths of 3/8" rigid steel high pressure line. This is the stuff you can use for brakes, power steering, etc. It is soft steel so it is bendable. You might also want to pick up a tubing bender for this, and a tubing cutter if you don't have one. You will also need a round "rat tail" file, and auto parts stores usually have pretty good deals on tools, so why not get one there too.
The first thing you want to do is cut the two main pieces of the rack that will go from the seatstay rack eyelets to the dropout eyelets. Crimp one end of each. I used a bench vise, but a hammer would work. So would vise grips if you are truly desperate or one of those sickos that enjoy using vise grips.
Once you have a nice crimped section, drill a hole in it to accept a standard M5 allen head bolt. You don't want a lot of play here, so try to use a bit that is just barely bigger than the bolt. I think I used whatever size is just smaller than 1/4".
Now bolt that sumbitch to the seatstay eyelet. You will have a long straight piece of tubing to work with at this point. Begin bending it to the shape you want the rack to be. Note: A milk crate is about 13" square. Use a tubing bender or some sort of v shaped round thing, like a swamp cooler belt pulley, to keep the tubing from kinking. You will see an example of kinking later in this article. Try not to do that if you can.
My goal was to get the rack level, and leave about as much clearance between the rack and the tire as there is between the brake bridge and the tire. Since you left the tubing long, you can get it where you want it than mark it for cutting, crimping, and drilling for the dropout eyelet.
Once you have the two main pieces done, you can make the little struts that join them and for the platform for the rack. Just cut 3 (or 2 or 4 or whatever) pieces the same length, and use your round file to "fishmouth" them so that they form a nice fit with the main rails. Remember that your file will stay sharp much longer if you only drag it across the metal in the cutting direction, never backwards.
It is now time to mix up a batch of J-B Weld! Awright! Just mix equal parts of the steel and the hardener. I like to use a nail or something else disposable so you don't have to clean it.
Spread J-B Weld on the end of the tubing, put the pieces where you want them, and use bungee cords to hold it all in place.
Next go back and make "fillets" with more J-B Weld. This is easier that it first appears because J-B Weld has a cool surface tension property that makes it self-smoothing. Just get it to stick where you want it, and it will slowly pull itself to a smooth finish.
Let it harden overnight, remove the bungee cords and you have yourself a rack. Paint it so it won't rust, and you are ready to roll.
POSTSCRIPT: This rack broke almost immediately. It turns out J-B weld is not as cool as I thought it was :(
posted by jsn at 9:24 AM
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