Park Tool RC-1 fills gaps and helps retain non-threaded parts like press-fit bottom bracket cups, sealed bearings etc.
It is recommended to first prepare press-fit surfaces with Park Tool AP-1 Adhesive Primer, which accelerates curing and eases future removal. AP-1 must be used to prep carbon fiber surfaces - failure to do so could result in permanently bonded parts.
CAUTION: Some painted surfaces can be sensitive to threadlockers, retaining compounds and primers. Test first on an inconspicuous area to see if it causes a stain or discoloration. Clean off any excess from painted surfaces immediately.
Park Tool offers a full line of products for thread preparation, including our line of threadlockers and retaining compounds: