There is Paterson contact printer which can be used for more than 36 frames of 35mm film contact sheet making (for example you have roll of film with 39 frames exposed, that is for example 6 strips with 6 frames and 7th strip with 3 frames, or other combinations like 7 strips with 5 frames, etc...). Its product number is PTP621, and use 24x30cm (9.5x12in) paper size, not 20x25 (8x10in). See more at:

That printer does not have guides for film strips, so it can be used for 35mm films, 120 films and large format films up to 24x30cm (9.5x12in) film size, but you have to line up film strips (sheet/s) manually and take care film strips (sheet/s) not to move when close it. It costs about 45 EUROS. If that is expencive, simply use piece of clear glass about 2mm thick. You can put your film strips into clear film sleeves, thus avoid direct contact of glass with film strips.