Toyo 810G tripod mounting block thread

[Lars Åke Vinberg]

I received a second-hand Toyo 810G today, was a bit surprised to find the tripod thread to be 1/4". There is a bushing in the block that reduces the thread in the block down to 1/4" from perhaps 1/2" or 5/8".

How do I mount this tripod block on a head with 3/8" male thread?

[Ralph Barker]

Have you tried removing the bushing? They often have a shoulder to allow for the driver slots, but have a 3/8" shank. The other alternative, of course, is to drill and tap a separate hole for 3/8". Quick job for a machine shop if you don't have numbered drills and a tap and die set.

[Lars Åke Vinberg]

Thanks, Ralph. Yes, the threads in the block are large enough for a 3/8" bolt to have a block party :-) My guess is that Toyo makes/made different bushings for 1/4" and 3/8" bolts, so that the threads in the block would always be protected.

Good tip re machining, thanks, I didn't think of that.

[Gem Singer]

Hi Lars,

Toyo makes a 3/8 in. bushing for that camera. Just remove the 1/4 in. bushing, and screw in the larger one. You'll need to find a dealer in your area, or order it directly from Toyo. In the mean time, why not figure a way to reduce the tripod head mounting screw to 1/4 in.?

[Jim Rice]

When I ordered my J-100 Ries from Badger, I didn't think to ask what size the screw was. Of course it turned out to be 3/8". I understand that it can be replaced, though I haven't found the need to yet.

[Gem Singer]

Lars, I meant the camera mounting screw. Please excuse the "senior moment". I realize what a large heavy weight camera you are dealing with. However, if you are also using a larger size mounting plate on your tripod head, a 1/4 in. screw, tightened down, should work fine.

[Jeffrey Goggin]

I'll double-check when I get home, but the tripod mounting block for each of my three Toyo G-series cameras has two mounting holes with bushings: A primary one positioned directly in the center of the base and another just enough off to the side enough so as not to interfere with the primary one. There are bushings in each of these mounting holes: One with 1/4-20 threads and the other with 3/8-16 threads. To attach the camera to a tripod, you can leave the bushings in their original holes and use the one that fits your tripod head or you can swap the correct size bushing into the center hole using a large, flat-blade screwdriver that fits into the slots cut into each of the two bushings.

Since my three Toyos were made at different times and purchased from different sources, the fact that all three tripod blocks are of a similar design (save for the fact that the 8x10 block is slightly taller, longer, and heavier) suggests this is how they they left the factory. If yours is different somehow, then perhaps it's been modified by someone over the years?

BTW, I know you're concerned about how the weight of this camera will effect your use of it in the field, but if you're willing to tinker with it a bit, it's possible to shed a few pounds by modifying it and/or swapping parts from a 45G. If you'd like details -- I've managed to get my 810G down to 15 lbs flat, a savings of over 3 lbs -- drop me a note...

[Lars Åke Vinberg]

Hi Jeffrey, I will drop you a note regarding weight savings - 15 lbs sounds like heaven!

Regarding the block - The underside is 70 mm (2.75") square. There is one thread in the dead center with a bushing, that's it. Near two opposite corners are two unthreaded holes, presumably for anti-twist support for dedicated camera support.

I did speak to Mamiya America parts department this morning, they said they think they have the right bushing and are sending one to me.

Worst case, as Ralph suggested, there is plenty of material for machining one or two threads.