This work shows a simple way of producing fixed bed microreactors or packed microcolumns by using electrodynamic focusing. Based on previous results that showed fibre focalization on orifices is possible, we explored this technique to electrospun fibres inside microchannels. Different polymeric nanofibres-either neat or composite, i. e. fibres containing particles-can be deposited without meaningful difference on deposition parameters, resulting in packed structures. Moreover, distinct substrates can be used for mask production, which can be reused with the respective setup. Finally, the use of a dry process shortens the process time, increasing productivity. (C) 2017 Portuguese Society of Materials (SPM). Published by Elsevier Espana, S.L.U.. All rights reserved.