/Building a fluidized bed for painting jigs

Building a fluidized bed for painting jigs

A fluidized bed is a great tool for powder coating you jigs, sinkers, and other relatively small items. It keeps the powder coat moving and prevents it from compacting which makes it very easy to get a quick and even coat on your jigs. You can buy all the hardware for your fluidized bed at the hardware store for about $5 or so, plus some household supplies like glue. The whole thing is powered by a small aquarium pump that you can pick up at the local pet store or Amazon.

Parts for making your own fluidized bed

So I have listed all of the things here so you can find that on amazon, but when it comes to the actual PVC hardware, get them at the hardware store. There is a major markup on amazon for them, those PVC test caps are $0.37 at Menards, there $4.00 on Amazon.

Cutting Your PVC

I start by cutting my PVC pipe. You need 2 pieces of pipe for each fluidized bed. The first piece is just a small cut that will fit inside of the female pipe adapter. Without it, the test cap won’t fit. Generally a piece between .5″ and 1″ will work for this. Doesn’t have to be too accurate. The second piece is going to be the chamber that holds the powder paint. You want to accommodate the fact that the powder will fluidized quiet a bit and expand, plus it will want to blow out the top some, so it needs to be long enough to contain it. For holding a standard 2oz container or Pro-tec, I use a 3-4″ piece of PVC for this.

Gluing PVC

First a quick primer on gluing PVC. When gluing PVC you are actually doing a solvent weld. The primer & glue/cement serves to soften the PVC and weld the two parts together. First, you start with the primer. You open the primer and use the included swap to wet both mating surfaces of whatever it is your gluing. In the first step, that will be the outside of the PVC pipe and the inside of the female adapter. You can purchase either clear or purple primer. Purple primer is the most common, its required by building code in most jurisdictions because it stains the pipe & thus proves to the inspector that you used it. In my case, I opted to use clear primer because it looks better than purple primer and I don’t intend to use it for household plumbing. After you have primed both pieces, then you repeat the process with the glue & immediately push the pieces together, giving a slight twist as you do so. Hold the pieces together for 15-20 seconds and the glue will then set.

Assembly your Own Fluidized Bed

The first step is to glue the small piece of PVC pipe into the inside of the female adapter. Apply primer to the outside of the PVC pipe and to inside of the female adapter (the non-threaded side!). Now apply glue to the same surfaces, push the pipe into the fitting and hold for 10-15 seconds. Giving the parts a slight twist as you push them together will help. After 10-15 seconds you can release and the parts should stay together. Next, apply primer to the inside of the pipe as well as the test cap. Apply glue to the same places and push the test cap in and hold. This seals the bottom of our fluidized bed.

Next is to glue up the top of our fluidized bed. Repeat the same process by applying primer to the outside of one side of the larger ~3″ PVC pipe and to the inside of the male adapter. Apply the PVC glue and assemble in the same manner. That is it for the PVC glue & primer. The 2nd test cap isn’t glued in, its just to use as a lid, set it aside until later.

Next we need to drill a hole so we can insert the valve for our fluidized bed. If you used the same valves as I did (linked above), the valve fittings will have a slight taper to them. You just need to select a drill bit that is larger than the smallest end of the valve, but smaller than the biggest end. That way the valve will get tighter as it’s pushed in further. Use the drill bit to drill a hole in the side of the female adapter, somewhere below the threads. I go roughly 1/2″ up from the bottom, but I just eyeball it. You want it below the threads, but higher then test cap so you don’t accidentally drill a hole in the bottom of your fluidized bed (don’t ask me how I know).

Now we need to glue in our valve. The valve will help us both adapt the air pump hose into the fluidized bed itself, as well as adjust the air flow so we’re not shooting powder coat all over the place. Simply coat the outside of the valve stem with thick super glue, and slide it into the hole you drilled. I put the super glue on pretty thick and once the valve is where I want it, I may add an extra bead around the hole if it doesn’t seem to have done so on its own. At this point, I hit it with a little bit of CA glue accelerator. It’s a small aerosol can that you spray onto the super glue and it makes it set almost instantly. It’s entirely optional, I just happen to have it laying around from some woodworking stuff that I do.

The last step before adding powder to your fluidized bed is to add some sort of membrane material. The membrane will allow the air to travel from below into your powder coat, but not allow the powder coat to fall into the bottom of the fluidized bed. You could use coffee filters or a variety of other mediums, but I find that a good old-fashioned brown paper grocery bag works really well. First, you cut a square that is a few inches larger than your female adapter. Then place the square over the female adapter. Now screw the male adapter into the female adapter, pinching the paper bag in the process. The paper bag will get pulled a few threads deep into the female adapter and then it will become very tough to screw them together any more. At this point, you are done. Look inside to make sure it didn’t tear (if it did, you went too tight, just redo it but stop just a little bit sooner). You can leave the paper bits hanging out the sides, but I like to tear it off the best I can so it looks a little neater. That’s it! Your homemade fluidized bed for coating jigs is done, now you just have to use it!

Using your DIY Fluidized Bed

Start by closing the valve on your fluidized bed (screw the thumb wheel in clockwise). Now pour in the powder coat that you plan to use. I personally just build a fluidized bed for every color I plan to dip (there are some accent colors that I apply without dipping, or use on spinnerbaits, or other lures that are too big to dip but that’s another post). I label the outside of the fluidized bed with whatever color powder coat it is and then pour the powder coat in. I build them large enough to hold the whole container, but I start with half just in case. Some powders end up being lighter then others and it’s nice to start off with the extra headspace if you need it.

Now its time to hook up the air pump. Connect the air pump to the fitting with the airline tubing. Shorter is generally better, but with a powerful enough pump nothing I would worry about too much. If your pump is like the one I used linked above, it has an adjustable output. I actually start with the pump all the way up (turned clockwise). Slowly start to open the valve. You will see air start to puff out the top. As you continue to open the valve, you will find a spot where the amount of “volcano’s” and big puffs of air goes down, but all of the fluid is moving around. That is the sweet spot. The powder is a lot less dense at this point and very even. This allows you to very easily dip your lure in. At this point, head your jig and quickly dip the jig down and back up. You should get a nice even coat that quickly glosses over (assuming its glossy powder coat like the pro-tec). If it fails to gloss over, hit it quickly with your heat gun, and heat up the next jig a little more before dipping it. Ideally, bake your finished jigs in an oven (toaster oven works great) and bake at 350 degrees for 15 minutes. For a whole article on the powder coating process itself, check out our page on that right here: Powder Coating Jigs. If you have any questions, feel free to post them below and we would be happy to answer them!