Installing Rogans on BEMI 208

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JamieDrouin
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Installing Rogans on BEMI 208

Post by JamieDrouin » Wed Oct 30, 2019 12:58 pm

I have a set of Rogans that I'd like to install on my BEMI 208, which has plastic D-shafts, and am hoping for some suggestions on how best to do this.

The large Rogan knob is for round metal shaft and has two set screws. If I delicately tighten onto the 208's D-shaft it remains very wobbly, pivoting on the small point of contact between the shaft and screws.

The medium and small Rogans are for metal D-shaft, and have an additional metal tension strip in the hole, which is very resistant about being inserted on the plastic D-shaft of the 208.

Tips, tricks, etc are appreciated. Perhaps the metal tension strip in the medium and small knobs can be easily removed, making it suitable for use on a plastic D-shaft?

Thanks!

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01235813
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Re: Installing Rogans on BEMI 208

Post by 01235813 » Wed Oct 30, 2019 1:54 pm

JamieDrouin wrote:I have a set of Rogans that I'd like to install on my BEMI 208, which has plastic D-shafts, and am hoping for some suggestions on how best to do this.

The large Rogan knob is for round metal shaft and has two set screws. If I delicately tighten onto the 208's D-shaft it remains very wobbly, pivoting on the small point of contact between the shaft and screws.

The medium and small Rogans are for metal D-shaft, and have an additional metal tension strip in the hole, which is very resistant about being inserted on the plastic D-shaft of the 208.

Tips, tricks, etc are appreciated. Perhaps the metal tension strip in the medium and small knobs can be easily removed, making it suitable for use on a plastic D-shaft?

Thanks!

Image

Image
I tightend both screws till they were just about to "grab", then I positioned them on the shaft and tightened them in place. I made sure that one screw would sit on the flat surface of the shaft. I didn't have to remove the tension strips.

Where did you get your rogans from? I got mine from SaModular and didn't have the issues that you described.

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JamieDrouin
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Post by JamieDrouin » Wed Oct 30, 2019 2:56 pm

I'm being very cautious about damaging the plastic shafts, hence asking before proceeding beyond the point-of-no-return. If I'm to use the metal tension inserts, and expect some resistance, that's fine. Just wish to know that going in ;-)

I'll have another go positioning the large knob as well.

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01235813
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Post by 01235813 » Wed Oct 30, 2019 3:04 pm

JamieDrouin wrote:I'm being very cautious about damaging the plastic shafts, hence asking before proceeding beyond the point-of-no-return. If I'm to use the metal tension inserts, and expect some resistance, that's fine. Just wish to know that going in ;-)

I'll have another go positioning the large knob as well.
I hear you :-)

After you go to fully tighten them down I would recommend giving the knob a full turn, making sure it runs parallel to the panel and doesn't get caught. I had to reposition one or two because it would have started to scratch the surface of the 218.

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tobb
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Post by tobb » Wed Oct 30, 2019 5:25 pm

When you put the Rogans over the D shafts are the knobs a bit loose?

Rogan bore is 1/4'' = 6,35mm, if the D-shafts are metric (=6mm) you are left with 0,35mm

You can then use a brass shaft adapter to convert 6mm D-shaft to plain 1/4'' bore.

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levelhead3
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Post by levelhead3 » Thu Oct 31, 2019 2:06 am

tobb wrote:When you put the Rogans over the D shafts are the knobs a bit loose?

Rogan bore is 1/4'' = 6,35mm, if the D-shafts are metric (=6mm) you are left with 0,35mm

You can then use a brass shaft adapter to convert 6mm D-shaft to plain 1/4'' bore.
This.

The only issue I ran into is the brass sleeves are technically for converting 6mm split shaft pots to 1/4". As long as the flat section of the D doesn't correspond with the set screw placement all is well, but if it does (as it was on a couple of the pots on my 255) the sleeves have a tendency to crimp into the void between the flat edge and outer circumference before the knob is completely tight.

A small section of chopstick perfectly filled the void and allowed the set screw to tighten completely.

I've heard rumors of a proper d-shaft conversion sleeve but have been unable to find them.

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tobb
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Post by tobb » Thu Oct 31, 2019 4:23 am

Yes,you have to fill the gap with pieces of pcb material (or something made of hard material)

Most of the time the D gap will be at the wrong position.

Knobs with two setscrews are an easier fit on the shaft.

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