Oops...I think we miscommunicated. FDM is fused deposition modeling, which uses filament and melts and applies it, layer by layer. SLA is resin printing that uses a UV laser in a tank of resin...the laser causes the resin to solidify. You might be confusing SLA with the type of filaments that are used with FDM printing, such as PLA. I know very little about SLA printing so I can't help you there.
Generally, the weakest part of an FDM print is the bonding between layers. Take a close look and see if it is separating along the layer lines. Thinner layers increase the potential number of failure points, but there is a sweet spot where layer separation is minimized. You can experiment with the layer thickness, somewhere around 0.24mm or even 0.28mm works well for me, but that's dependent on the printer. The other thing is, if you are using PLA, try a more flexible material like PETG. If you have an enclosed printer, there is also ABS or even ASA. ASA has exceptional UV resistance and is preferred for outdoor printed projects, but like all materials it has a learning curve.
There are also slicers that support varying layer thicknesses, so different parts of the print can be printed thicker or thinner as desired. Assuming you are separating along the layer lines, that is.