ACRYLIC DRUM CRACK REPAIR I've had quite a few questions come my way regarding crack repair in acrylic drums so I thought I'd give you my skew on the subject. First off I have no problem with a drum with a crack in it. Some, if not most, cracks are pretty much not a problem, as long as they are small and non-traveling. For example, I have a 13" tom with a crack from the top mount hole to the edge. This drum sounds fine and the crack is not going anywhere (it's done with what it wants to do). It holds a head tighter than any and it's just fine. The crack that travels from one edge to the other might represent a problem (the drum looks like the letter "C") but once the crack is repaired and the drum reassembled it should be okay. One big problem is the crack that is starting at one of the lugs or from the mount. This is a crack we want to stop before it goes to far. We have two options here, drill the end of the crack to stop any further travel, or weld the crack with a chemical weld, (or both depending on where it is). Drilling I will leave up to You. Let's deal with a chemical weld here. What is a chemical weld? There are quite a few products on the market that are specifically designed for acrylic bonding. Tap Plastics, Weld-on, just to name a couple of manufacturers, sell very good products specifically designed for this purpose. The agent is not necessarily glue or cement but rather a solvent that melts the acrylic and allows it to meld together. For our purpose we will select an acrylic bonding agent with a Very light viscosity (thin, like water). We will also need the following: A sturdy work surface. Applicator (Hypo-25) available from Tap Plastics and other plastic outlets
Shop towels Strap clamp (if necessary) Bonding agent, previously mentioned (I use Tap Plastics acrylic cement and Weld-on #'s 4 and 5) Various tools to remove heads and hardware
Okay, let's get started in a WELL VENTILATED place Remove any obtrusive hardware (some hardware may keep the drum from rolling around) Make sure the crack and surrounding area is clean and free of dust and debris as well as grease. Secure the drum to the work area (maybe a couple of heavy blocks with some towels wrapped around them placed on each side of the drum will help. You just need to keep it steady. If you have to put a strap around the drum to hold the crack together place a wood dowel on either side of and away from the crack to raise the strap off the surface of the drum (you don't want to glue the strap to the drum).
Place the crack to be repaired at the bottom of the work area. It's easier to work from the outside of the drum but the agent may drip down the sides creating a mess. Make sure the crack is free and off the surface of the work area
Now the easy part. Open the bonding agent and dip the applicator into the solvent and draw some into the bottle( you can also use a small funnel to fill the bottle). With the bottle upright squeeze the bottle slightly and release to create a vacuum while turning it upside down. (This will prevent dripping). Draw the point of the applicator along the crack (do not push the tip into the acrylic, rather drag it along the crack) while squeezing the bottle gently. The agent will flow into the crack through capillary action (it will suck into the crack like a straw).
Let the bonding agent do its work. After a few minutes the crack will be no more. Do not remove any straps or test the crack for at least 2 hours. In fact, do not test the crack at all unless you are unsure of your work. If the crack repair fails, do it again after a good cleaning with some alcohol rub. You will still be able to see the crack but it will be solid and inflexible. Do not sand or polish the area for at least 72 hours at this point the repair is at 80% strength and can be woked safely. Sand and polish as needed when the crack has had time to set.
This may not be the strongest fix but it works well in non load bearing areas and for small cracks around the lugs. There are some others that will yield better or worse results and some that will result in catastrophe. You decide if it's worth the trouble or if you are brave enough to give it a try. Good Luck, Ken Verducci
