Chinese 10-10

[fgregorio]

My scale of choice is a RCBS M500.
I put a brush bristle stuck to the center line of the body, not on the pointer. You can fit 3 to 5 widths of the bristle on the width of the white center line etched on the balance beam. Too thin to see accurately on naked eye but perfect when magnified full screen.
Use a good quality 12 MP webcam ( Logitech C615) pointed at the scale lines and magnified all the way.
The scale is in a straight line away from me (instead of the normal position).
I make sure that the pan wire hanger sits only on the knife edges and doesn't touch the side stops (keep friction to a minimum).
I make sure that the beam sits only on the main knife edges.
My own conclusion is that scale sensitivity lies on the good supervision of the main beam knife edges and that scale repeatability rides on the supervision of the wire hanger knife edge. I check them for alignment before every round weighed.
On my electronic milligram scale I got the exact milligram 42 out of 50 rounds weighed. The other 8 were 1 milligram over (1 kernel of varget).
I prefer my beam scale over to the electronic one because it will read every kernel. Electronics may need more than one kernel to trigger a response and then provide a sum of the total change.
If anyone wants pics of the srtup, I can post as a reply to this thread.
Just my 10c.

 

[hoz53]

My scale of choice is a RCBS M500.
I put a brush bristle stuck to the center line of the body, not on the pointer. You can fit 3 to 5 widths of the bristle on the width of the white center line etched on the balance beam. Too thin to see accurately on naked eye but perfect when magnified full screen.
Use a good quality 12 MP webcam ( Logitech C615) pointed at the scale lines and magnified all the way.
The scale is in a straight line away from me (instead of the normal position).
I make sure that the pan wire hanger sits only on the knife edges and doesn't touch the side stops (keep friction to a minimum).
I make sure that the beam sits only on the main knife edges.
My own conclusion is that scale sensitivity lies on the good supervision of the main beam knife edges and that scale repeatability rides on the supervision of the wire hanger knife edge. I check them for alignment before every round weighed.
On my electronic milligram scale I got the exact milligram 42 out of 50 rounds weighed. The other 8 were 1 milligram over (1 kernel of varget).
I prefer my beam scale over to the electronic one because it will read every kernel. Electronics may need more than one kernel to trigger a response and then provide a sum of the total change.
If anyone wants pics of the srtup, I can post as a reply to this thread.
Just my 10c.

That is good info/ thanks for the report

 

[BoydAllen]

My scale of choice is a RCBS M500.
I put a brush bristle stuck to the center line of the body, not on the pointer. You can fit 3 to 5 widths of the bristle on the width of the white center line etched on the balance beam. Too thin to see accurately on naked eye but perfect when magnified full screen.
Use a good quality 12 MP webcam ( Logitech C615) pointed at the scale lines and magnified all the way.
The scale is in a straight line away from me (instead of the normal position).
I make sure that the pan wire hanger sits only on the knife edges and doesn't touch the side stops (keep friction to a minimum).
I make sure that the beam sits only on the main knife edges.
My own conclusion is that scale sensitivity lies on the good supervision of the main beam knife edges and that scale repeatability rides on the supervision of the wire hanger knife edge. I check them for alignment before every round weighed.
On my electronic milligram scale I got the exact milligram 42 out of 50 rounds weighed. The other 8 were 1 milligram over (1 kernel of varget).
I prefer my beam scale over to the electronic one because it will read every kernel. Electronics may need more than one kernel to trigger a response and then provide a sum of the total change.
If anyone wants pics of the srtup, I can post as a reply to this thread.
Just my 10c.

By all means, post pictures.

 

[LarryDScott]

I purchased a NIB Chinese 10-10 scale early this yr, and find it works just fine. I'm sure it would be better fine tuned, but as far as I can tell, it's as good as one could expect. I gave a 100.00 for it delivered. LDS

 

[fgregorio]

Set up of the direction of the scale. This allows me to see and check at all times the alignment of the beam and main knife edges. It also makes the handling on the pan a lot easier. Less disturbance on the pan wire hanger. If it falls out of alignment I can see it as it happens.

 

[fgregorio]

Making sure that the wire hanger sits on the knife edges only.

 

[fgregorio]

Same for the main knife edges. Keeping friction to a minimum is Paramount .

 

[fgregorio]

This is what I see on my computer screen. The bristle is too thin to see well on naked eyes.
The pic doesn't make justice to the clarity that I see on screen.

 

[BoydAllen]

In the past just to see if I could, I set my scale up with the pan toward me and the scale at a right angle to the edge of the desk that I reload on with a webcam imaging the beam pointer and scale. I figured out how to dump powder directly into the scale pan without bouncing out, and had my RCBS trickler set up to finish the charge. I figure that it would take me perhaps 18 seconds to throw trickle, dump in the funnel and return the pan to the scale, largely depending on how long it took to trickle....sort of a poor man's Prometheus...a lot cheaper than three grand. If any of you have come up with ways to dump powder directly into a balance scale's pan from a powder measure, I would like to see your setup. Mine was rather crude but it worked.

 

[fgregorio]

In the past just to see if I could, I set my scale up with the pan toward me and the scale at a right angle to the edge of the desk that I reload on with a webcam imaging the beam pointer and scale. I figured out how to dump powder directly into the scale pan without bouncing out, and had my RCBS trickler set up to finish the charge. I figure that it would take me perhaps 18 seconds to throw trickle, dump in the funnel and return the pan to the scale, largely depending on how long it took to trickle....sort of a poor man's Prometheus...a lot cheaper than three grand. If any of you have come up with ways to dump powder directly into a balance scale's pan from a powder measure, I would like to see your setup. Mine was rather crude but it worked.

In my setup I found it to be the most convenient to use a bench rest powder thrower, put the pan on the scale and then use a Dandy Products Auto Trickler. Fr me it works a lot faster and more accurate than my previous charge master.

 

[BoydAllen]

Yes but if you could throw powder directly into the scale pan while it was on the scale, it would be even faster. I have one of the Dandy Auto Tricklers and I find that I can do well enough with my RCBS that I do not take it out of the closet. In fact, I may put it up for sale. For what I do, it offers no advantage.

 

[BoydAllen]

I got the magnets this afternoon, and, long story short, they did not work. The reason was that the scale's magnets poles face each other as if they are two very flat horseshoe magnets. The result of this was that the magnets that I bought would not sit squarely on their ends. Man, these little neodymium magnets have a lot of force. What I did do was take the scale magnets out, and place the neodymium magnets on each pole of the original magnets for a bit. I think that this made the original magnets a bit stronger. The whole thing is back together like it was before, with no additional magnets. After that, I did a little tuning on the wire loop that supports the pan assembly so that it cannot shift on the knife edges. Also, the heavy wire part of the pan holder was touching the pan, not letting it sit squarely, so I did a little bending and fixed that. Generally speaking I like to work on this kind of problem until I start to feel impatient, and then I know to set it aside for the next day.

 

[BoydAllen]

Follow up: The magnets did not align with the existing ones the way that I thought that they would because the poles (of the factory magnets)are facing each other when they are in their installed position. This meant that the neodymium magnets would not sit squarely on the ends of the factory magnets, which causes alignment problems.

One thing that I did try was to take the magnets out of the scale and place a neodymium magnet on each pole, and leave it that way for a while to see if that would strengthen the factory magnets. It may have. Although I am finished with the magnet experiment for the moment, I did some additional tuning on the wire double loop that supports the pan holder, slightly bending it so that it cannot shift on the knife edges. Also the heavy wire part of the pan holder was contacting the scale pan, so I did a little bending to do away with that contact. My experience is that I can only work on problems like this for a limited time after which my impatience reduces my ability to analyze and come up with solutions. I will put this away for a day or so and work on other things.

 

[hoz53]

I got the magnets this afternoon, and, long story short, they did not work. The reason was that the scale's magnets poles face each other as if they are two very flat horseshoe magnets. The result of this was that the magnets that I bought would not sit squarely on their ends. Man, these little neodymium magnets have a lot of force. What I did do was take the scale magnets out, and place the neodymium magnets on each pole of the original magnets for a bit. I think that this made the original magnets a bit stronger. The whole thing is back together like it was before, with no additional magnets. After that, I did a little tuning on the wire loop that supports the pan assembly so that it cannot shift on the knife edges. Also, the heavy wire part of the pan holder was touching the pan, not letting it sit squarely, so I did a little bending and fixed that. Generally speaking I like to work on this kind of problem until I start to feel impatient, and then I know to set it aside for the next day.

you could put an electromagnet(s) on there and hook up a potentiometer so you could tune your dampen. . you can also use those extra magnets on your torpedo level--very handy. i am an impatient guy myself and probably an ADD victim so I have many unfinished projects around here.

 

[BoydAllen]

Then there is this. Before this latest scale arrived I had four scales, three tuned balance type and one electronic. At some point the need to fiddle with something that you have that many of becomes much less of an emergency.

 

[hoz53]

Then there is this. Before this latest scale arrived I had four scales, three tuned balance type and one electronic. At some point the need to fiddle with something that you have that many of becomes much less of an emergency.

Well yes I hope you never considered it an emergency to start with. Hopefully it was somewhat of an interesting project and that was all it was supposed to be.

Then there is this. Before this latest scale arrived I had four scales, three tuned balance type and one electronic. At some point the need to fiddle with something that you have that many of becomes much less of an emergency.

I would hope it wasnt an emergency at all. Dont throw it in the pond yet. I imagine youve helped some guys who would not have purchased an import before.

 

[BoydAllen]

Well yes I hope you never considered it an emergency to start with. Hopefully it was somewhat of an interesting project and that was all it was supposed to be.

I would hope it wasnt an emergency at all. Dont throw it in the pond yet. I imagine youve helped some guys who would not have purchased an import before.

Emergency was a poorly chosen word. It was never that. One thing that I had come up today...my zero was not as constant as it had been. Looking at the scale it seemed that the "frame" was out of level, even though I had done that previously. I put a loose level vial on the scale and re-leveled the scale frame. Noticing that additional weight was needed in the pan holder tuning weight container, I cut as small sliver off of the corner of a out of date AAA road service card (plastic, like a credit card) threw it on the scale pan, trimmed it slightly until the scale read zero, and put it in with the steel shot in the pan holder compartment. After that the scale worked as it should have.

 

[hoz53]

Emergency was a poorly chosen word. It was never that. One thing that I had come up today...my zero was not as constant as it had been. Looking at the scale it seemed that the "frame" was out of level, even though I had done that previously. I put a loose level vial on the scale and re-leveled the scale frame. Noticing that additional weight was needed in the pan holder tuning weight container, I cut as small sliver off of the corner of a out of date AAA road service card (plastic, like a credit card) threw it on the scale pan, trimmed it slightly until the scale read zero, and put it in with the steel shot in the pan holder compartment. After that the scale worked as it should have.

In the past I never thought these scales were that sensitive but now I know they are. I wonder why the scale level changed. One thing I noticed is the leveling screw on mine was loose and I thought I would put a different bolt (longer) with a jam nut. another thing i do is fasten the frame down so it stays in the same place.

 

[BoydAllen]

That was not the issue with mine. I set the scale to zero and adjusted the leveling screw until it was balance at that value, and then put a level vial on the scale frame to see if it was level. As I suspected, it was not. I will probably never know what caused the change, but I am glad that I caught it, because fixing it made the scale work better. The vial that I used was one of four that I purchased to replace one in a scope mounting tool that I have had for a long time. After I had fixed the tool, there were three left over. On the top of the 10-10 there are two slots where the cover attaches. I laid the vial on one of those slots, which acted like a V block, keeping it from rolling off of the scale. Some time back, I had checked the side to side level of my desk and so I knew that since it is level that if the gap between it and the bottom of the scale was not the same from end to end that it was likely that the scale was off.