CH/BH2 Compatibility

[Harold]

Can anyone tell me if the focusing assembly (coaxial knobs, gears, etc) for a CH microscope can be used in a BH2?

Thanks

[lorez2]

I don't think so. They are different models and different generations.

lorez

[Harold]

I don't think so. They are different models and different generations.

lorez

Different generations or not, The exploded views available on Alan Wood's site of the CH Series and the BH2 microscopes clearly show that both microscopes used the exact same mechanism right down to the focus preset lock. Same gear box, same roller bearing focusing sliding block, the same fine focus mechanism in the right focus knob. Big manufacturers of anything don't like to be forced into tooling changes without good reason.

What I'm asking about has more to do with dimensional compatibility of the overall focus mechanisms.

[josmann]

Shoot Carl an email - he can probably answer this conclusively.

[lorez2]

I went to the shop and looked at a CH and a BH2 and am changing my original response from "I don't think so", to "no. they are not compatible.

lorez

[Harold]

I went to the shop and looked at a CH and a BH2 and am changing my original response from "I don't think so", to "no. they are not compatible.

lorez

May I ask why you say that? Did you take any measurements? Just curious.

[carlh6902]

Many, but not all, of the low-level focus parts are interchangeable between the BH2 and CH. The AA7826 gear in the fine focus knob is, whereas the other gears are not, if I recall correctly. The pinion assembly is similar, but different parts (the knob-to-knob distance is different).

Carl

[Harold]

Many, but not all, of the low-level focus parts are interchangeable between the BH2 and CH. The AA7826 gear in the fine focus knob is, whereas the other gears are not, if I recall correctly. The pinion assembly is similar, but different parts (the knob-to-knob distance is different).

Carl

Thanks so much for lending an authoritative voice to the discussion. It's the AA7826 that I'm interested in. As similar as the assemblies look in the drawings, I though the dimensions, like the length of the brass pinion housing might be different, but I couldn't find any drawings with dimensions called out.