The solvents I tested, starting with the most satisfactory:
- SCIGRIP 2007 (formerly Weld-On 2007) tinted the SD300's vinyl parts very quickly, reaching full color in 15-20 seconds. It also strengthens 3D printed parts and leaves a glossy finish.
- Oatey Un-purple Primer was almost as effective as SCIGRIP. It's a PVC pipe primer without the usual purple stain; instead it contains a UV-sensitive fluorescent dye that makes treated parts glow under blacklight.
- PVC Pipe Cleaner with THF (various brands) was substantially less effective than the solvents above, and it took longer for parts to absorb the dye. Look for THF or tetrahydrofuran under the caution label.
- PVC Pipe Cleaner without THF was least effective. It took more time, it did not strengthen parts, and it did not leave a glossy finish like the choices above.