The majority of rain barrels that I see people using are the Blue ones you see in the thumbnail. These have a special cap that I have found tricky to remove. After using screw drivers and pliers and anything I could get ahold of to open these for cleaning. I thought to myself "There has to be an easy way of opening these." There is, I made a special bit using basic tools that most people will have I also will list other simple tools that can be used.
The tools that I used are.
1. coping saw
3. box cutter
The materials I used are
1. plastic cutting board or scrap plywood
2. plain screws
3. super glue
Step 1: Drawing the Template
The easiest way that I found to get an exact template is do a graphite rubbing. Take your paper, in my case just printing paper. Lay it on top of the cap. Lightly press the pencil down and rub it around to show where the contacts are. Once you have a decent rubbing of it I recommend tracing the lines heavier to make it easier to cut out later.
Step 2: Transferring the Template
Once you have your template cut out to your satisfaction. take the material you will be using and trace it out. Here I have some plywood and plastic from a cutting board. I have found that the cutting board plastic works quite well. It is easy to cut with a coping saw and is quite sturdy. Only a few bucks for a large one compared to a large piece of plywood.
Step 3: Hydration
When working with hand tools it is easy to get caught up in the project and want to finish quickly. Be sure to drink your water and stay alert when working with sharp tools.
Step 4: Cutting
In this part I used chisels but you can use a screw driver if you wanted. I have even used to small wrench from a dremel tool for part of this. What you will be doing in this step is using the coping saw to make relief cuts along the lines. Once you have enough cuts to where you feel they will break away nicely, take your tool of choice and start carefully breaking the chunks away. The plastic will break easier than the wood, and will not splinter like the wood.
~ If you are using wood, you will want to use a file to take those peaks off. Those do not happen when using the plastic. I found that the fastest way to take spikes off after breaking the reliefs is angle the coping saw at a 45 degree angle and use the teeth like a harsh file. If you do not have files, a coping saw will do fine but will be slightly rougher than if using a file.
Step 5: Working Your Way Around
When I was doing this I used to clamps on a bench. Once I worked my way around it was too small to use the clamps anymore. I used a normal screw and a screw driver and drove it into the side of my door work bench. It allows easy access to all the parts you need to file and saw. Just take your time and keep as close to the lines as possible.
Step 6: Fitting
After I sawed the bit out, and filed it down. It still was bit of a tight fit. I used a box cutter and trimmer the edges carefully and fit right in. I used the screw hold from earlier on the door bench to pull it back out from the test fitting.
Step 7: Using It
Alright, so you have your bit that fits in correctly, now how do we use it. I took some scraps of the cutting board I used and made spacers, I glued them down with super glue so they didn't slide around too much and used that screw to my advantage. You can use whatever method you think will work. But I just use these spacers and some vice grips. Now I am able to get into my rain barrels and wash them out or do any kind of maintenance. Add a new line for a new barrel. Whatever you need to do you can get in there easily now.