• Mitrpak

MITRPAK Power Transmission Products is a company based in Uxbridge, MA, USA, manufacturing power transmission products.

MitrPak R-081-M


The MitrPak R-081-M is one of the «two gearboxes that are being used in conjunction with the 330X360 folding carbon fibre propeller and the easily driven stabilised monohull», says boat designer Rick Willoughby.


Mitrpak R-081-M


Our user-innovators' reviews and recommendations


Rick Willoughby:

«This box (with 1:1 ratio; insert by webmaster) has rated continuous torque of 5.6Nm. This compares with cruising torque of 4Nm and short term sprint torque of 14Nm.
The latter being within 3X the rating, which is possible providing solid shear pins are installed rather than the standard roll pins.
The box weighs 1.3kg.
The MitrPak R-082 box, having 1:2 ratio, is NOT suitable for sustained use.
The MitrPak box can be dismantled without destroying the shaft seals.
The MitrPak box is pre-lubed with grease.»


Michael Lampi: 5-stars (five stars out of five)

«I highly recommend the MitrPak 1:1 gearboxes for curved-shaft propulsion systems. With its finished aluminum housing, stainless steel shafts and double seals it is about as good as it gets for service in a marine environment.
I use the R-081 gearbox.
You definitely need to size the gearbox according to the loads placed on it. It is possible to use a gearbox with slightly lower rating if you request it with solid pins to secure the bevel gears rather than hollow roll pins.
MitrPak produces a compact, well designed product that appears to hold up in a marine environment. Should service or design assistance be needed, they have been very supportive of human powered boating enthusiasts.»


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