If you have a tight drum set-up getting a regular mic on the snare is a problem because it stick up into the playing area. There are 45 degree mics available but if you already have a good mic why buy a new one. You can make one.
My subject mic is an old Peavey PVM 45.
Step 1: Dismantle and Cut in Half
Dismantle your mic by loosening the screw and removing the 3 pin end and unsolder the wires. Mark the solder points so that you know where to replace the wires when you have to put it back together. Twist out the diaphragm end and set the two parts aside. Measure how deep the guts of the diaphragm section goes and mark it on the outside of the mic. Be sure you will have enough on the tail end of the mic to hold in the mic clip when you are finished.
Now saw the mic body in half with a band saw or hacksaw.
Step 2: Position the Mic Pieces
Drill a hole in the top half of the mic to hook a small bungee in. Pull the bungee down through the bottom half of the mic, pull it tight and clamp it with vice grips.
Step 3: Secure in Vice
The top half should sit nice and snug into the round of the bottom half.
Step 4: Mix Up Some JBWeld
Mix up some JBWeld
Step 5: Fill the Seam
Fill the join with a nice seam of JBWeld inside and out and let it set overnight.
Step 6: Build Up the Inside
Once the JBWeld has set slide a piece of paper inside the mic to make a support for the back fill. Pack inside with cotton. Pack outside with steel wool.
Step 7: JBWeld the Elbow Hole
Fill over the steel wool with a thick layer of JBWeld. To hold the JBWeld until it firms up wrap the elbow with sandwich wrap.
Step 8: Sand and Paint
Sand the JBWeld to a nice smooth curve. Pull out the cotton and paper backing inside the mic. The steel wool has adhered to the JBWeld and needs a non conducting surface over it (silicon or something).
Clear coat the mic. Tremclad works great if you ca find a can of the old formula which was made in Canada by Tremco. But don't bother using the Rustolium version because the nozzles never work and it is not very glossy.
Step 9: Re-wire
Tuck the wiring of the diaphragm back down inside the mic casing and twist it in to place. Solder the wires back onto 3 pin end and screw it in place.
Done... a 45 degree microphone for 50 cents worth of JBWeld and a splash of gloss paint.