Beam Ballance Scale Recommendation

[CatShooter]

I'm surprised no one has mentioned Redding. Unlike ALL the other scales as far as I know, these are 100% made in the USA and very possibly by a veteran.
I used a USA made RCBS 10-10 a long time and seems to me, the magnetic dampening works better on the Redding.

If the dampening doesn't work the way you like - then change the magnets.

I put larger magnets in my M-5 over 35 years ago, and it still is the best scale I ever had.

Currently, the Redding is one of the best.

 

[6mmcldasher]

Redding #2

 

[1066]

Two possibilities spring to mind. I would first check the pan hanger stirrup and the little knife edge it hangs on. Give them a scrub with a tooth brush and a little spirit and make sure the stirrup is free to swing and not rubbing the sides of the cut grooves. I would also check the tips of the knife edges, they should come to a point in line with the knife edge, then if they touch the bearing endplates they pivot on a single point, if they are rounded they will try and scribe an arc and hang up a little.

Try and isolate the problem, make sure the knife edges aren't touching the end plates and see if it still fails to zero.

Any comment on the calibration of the heavy poise?

Thanks. I do notice one of the knife edges is not perfectly straight to the end, it is curved back ever so slightly like a scimitar. I have tried positioning the pivots to either extreme (towards the end plates) as well as in the middle, but did not notice a difference. However, I will revisit that, and look to restore the edge as well. I will also take a look at the pan hanger and pivots.

Over the years the serrations in the beam are bound to wear a little, especially in the 20-50 grain zone. I would have a gentle scrub across the beam (I use a soft brass brush) and then have a careful look through an eye glass for any burrs or debris stuck in the grooves. The little washer that locates in the groove must sit right at the bottom of the groove - just a thou or so either way will effect the reading. Any burrs can be eased away with a sharp scalpel. Just be careful, we're talking tiny amounts here.

Typical damaged knife edge

 

[Brians356]

I put larger magnets in my M-5 over 35 years ago, and it still is the best scale I ever had.

I don't know if the M5 design changed over the years, but mine has cylindrical magnets which have a deep notch or saddle in them which fits over a key in the casting. Probably no off-the shelf magnet would be a drop-in replacement. Could you provide details of what magnets you used, and how they are installed?

 

[justpassinthru]

I'm surprised no one has mentioned Redding. Unlike ALL the other scales as far as I know, these are 100% made in the USA and very possibly by a veteran.
I used a USA made RCBS 10-10 a long time and seems to me, the magnetic dampening works better on the Redding.

If the dampening doesn't work the way you like - then change the magnets.

I put larger magnets in my M-5 over 35 years ago, and it still is the best scale I ever had.

Currently, the Redding is one of the best.

The 10-10 wasn't replaced because I didn't like the magnetic dampening, it just didn't work like it did in 1975 when I bought it. I'm sure it could be fixed, but I didn't want to be without a scale while it was sent off for repair. I dang sure didn't want a Chinese RCBS, so I looked for another option.
Started using the Redding, and saw what I had been missing all these years.

 

[Brians356]

Over the years the serrations in the beam are bound to wear a little, especially in the 20-50 grain zone. I would have a gentle scrub across the beam (I use a soft brass brush) and then have a careful look through an eye glass for any burrs or debris stuck in the grooves. The little washer that locates in the groove must sit right at the bottom of the groove - just a thou or so either way will effect the reading. Any burrs can be eased away with a sharp scalpel. Just be careful, we're talking tiny amounts here.

Actually my beam seems pristine in the 0 to 75-gr area, this thing could have seldom been used. Very clean and no wear to the black finish anywhere on the beam, except higher up towards 100-gr there are a few burrs which I will address. But I will don the OptiVISOR and have a closer squint.

 

[CatShooter]

I put larger magnets in my M-5 over 35 years ago, and it still is the best scale I ever had.

I don't know if the M5 design changed over the years, but mine has cylindrical magnets which have a deep notch or saddle in them which fits over a key in the casting. Probably no off-the shelf magnet would be a drop-in replacement. Could you provide details of what magnets you used, and how they are installed?

They are standard, black round magnets - I have seen them for sale for most of my life. Radio Shack sells them, many hobby stores sell them.

I first put them in place by stuffing tissue paper to see if they would work - they worked so well, that I just left them there. This is the first time I have had it apart in 35+ years.

I recall that there was a "key"... you can see that the inner walls that the magnets are against, have been modified.

With the new magnets, dropping a full pan on the scale will result in the beam swing past "0"... then slow down and go past "0" once again and over shoot by 1/10th, and then come to a stop - it is fast! Maybe less than 1.5 seconds to full stop.

But sensitivity is not sacrificed - the beam will move with one granule of H-322 (which is 1/17th of 0.10 of a grain = 0.0059 of a grain) placed in the pan.

If there is anything in the way, like a key... Dremel is your friend.

 

[Brians356]

Thanks. The notches in the magnets served, I believe, to create a weaker zone of attraction centered on, and straddling, the zero mark. Presumably this was intended to mitigate any tendency for the magnets to influence where the pointer settled. I notice my 5-0-5 has two elongated bar magnets, which may be a more effective approach to speedy damping without influencing the static position. I have some small but extremely powerful neodymium magnets, I may stick one on either side of the casting's protrusions (four in total) and see how that works.

 

[Brians356]

Any burrs can be eased away with a sharp scalpel. Just be careful, we're talking tiny amounts here.

Typical damaged knife edge

I'm loathe to remove any burrs from the beam. Wouldn't lightening, however slightly, one side of the beam throw it off kilter? Or is that simply mitigated by the scale leveling screw? I'm sure I have a lot to learn about balance beam scale fundamentals.

My knife edges look pristine compared to the damaged one you show. I'm not sure mine can be improved much.

 

[1066]

Any burrs can be eased away with a sharp scalpel. Just be careful, we're talking tiny amounts here.

Typical damaged knife edge

I'm loathe to remove any burrs from the beam. Wouldn't lightening, however slightly, one side of the beam throw it off kilter? Or is that simply mitigated by the scale leveling screw? I'm sure I have a lot to learn about balance beam scale fundamentals.

My knife edges look pristine compared to the damaged one you show. I'm not sure mine can be improved much.

The knife edge shown there is probably beyond repair - not the fact that it looks like rats have been chewing on the edge but the chip at the end. A simple remedy might be shortening the pin but, depending on the scale, something like a 5-10 or a 10/10, too much side to side travel may lead to the damper plate touching the scale body.

Fine tuning the beam serrations is a painstaking job, every action has a reaction. Problems with the beam serrations don't usually cause inconsistency i.e it will consistently read incorrectly at one specific weight.

Constant use of a set of checkweights is required for this work.

 

[Brians356]

Constant use of a set of checkweights is required for this work.

Noted. But what is acceptable error in this class of scale? I mentioned a consistent -0.1 grain error at 50-gr setting. That's fairly small, but if it's repeatable, it seems like the scale could be adjusted to correct that. Yes? Or do the check weights simply disclose any errors, and I'm required to document and factor them in myself?

 

[CatShooter]

Constant use of a set of checkweights is required for this work.

Noted. But what is acceptable error in this class of scale? I mentioned a consistent -0.1 grain error at 50-gr setting. That's fairly small, but if it's repeatable, it seems like the scale could be adjusted to correct that. Yes? Or do the check weights simply disclose any errors, and I'm required to document and factor them in myself?

Accuracy is not important (within reason) repeatably and sensitivity are of paramount importance.

Scale #1 shows a 50gr check weight to weigh 50 grains average with 20 weighings. But each weighing is 52, 49, 47, 54, 52, etc...

Scale #2 shows a 50gr check weight to weigh 52 grains, and every weighing shows 52.000 +/- 0.001 grains.

Which scale do you want?

I'll pick door #2 every time. You are not having to weigh gems and sell them, you are weighing loads which you (hopefully) worked up from 10% under, so what difference does it make, what the exact weight is??

 

[Brians356]

... what difference does it make, what the exact weight is??

I don't know.

 

[1066]

Catshooters right - Consistency is the name of the game, exact weigh is rarely important. If you work up a load with your scale and you can repeat that load every time, that's exactly what you want.

Consistency and repeatability.

If you look at these "scales" you will find there aren't even any numbers on it. An excellent tool for repeatability though.

 

[Brians356]

Catshooters right - Consistency is the name of the game, exact weigh is rarely important.

Fair enough. But you might expand on your comment "Constant use of a set of checkweights is required for this work." The reader might reasonably but mistakenly deduce that your check weights are being used to verify the scale is reporting exact weight.

 

[1066]

Catshooters right - Consistency is the name of the game, exact weigh is rarely important.

Fair enough. But you might expand on your comment "Constant use of a set of checkweights is required for this work." The reader might reasonably but mistakenly deduce that your check weights are being used to verify the scale is reporting exact weight.

If I'm tuning a set of scales I like to know, not only are they consistent and sensitive but they are accurate as well. Almost any work carried out on the beam will effect the accuracy, if you want to add and extended pointer it will need balancing at the other end.
The locating washer on the main poise needs to sit down in the groove exactly the same at every groove, just the tiniest different will mean the main poise, maybe about 200 grains is either a little too far forward or back and it will cause a significant difference in the reading. If you're not using check weights you have no benchmark to work to.

Making the scale accurate is not the same as making it repeatable or sensitive.

This video shows my 502 scale quite happily weighing to within a kernel or so of Varget powder.

http://bulletin.accurateshooter.com/2014/04/forum-member-rigs-video-display-for-balance-beam-scale/

 

[amlevin]

I'm partial to simple.

Seriously, I find that nice modern digital scales work just fine. The key to accuracy is to have some accurate test weights.

 

[chkunz]

I just bought a new set of beam balance scales RCBS model 5-0-5.
This is just an ordinary mid-price scale, nothing extraordinary, very plain model.
Over the years when I have used the check weights on my old Lyman M5 1966 model scales they are always within a half a tenth of a grain as compared to the check weights which is excellent for this type of instrument. When I checked the new RCBS model 5-0-5 with the check weights it is right on, not just close but right on as close as I can read the pointer. Truly amazing.

 

[WindSurgeon]

I have a 1988 Dillon Precision beam scale. Very simple device and it has worked well for me for many years. I have invested in several electronic scales and find them too slow and I always feel that the constant calibration after x number of rounds finds me doubting their consistency. As stated previously by a poster, consistency is the key. Out of the box my Dillon is sensitive enough to move with one grain of powder dropped into the pan, and weighing charges for confirmation on my best electronic scale shows +/- .05 consistency which for most shooting disciplines is enough.

Here are some techniques/tips for getting consistency with a beam scale. Some hold true for electronic as well:
1. Eliminate all external air movement if possible (shut the AC/heat vent, close windows, etc).

2. Fix the scale to a level surface so the base can not move after you zero it before each session. Critical because if you move the base in any way, there is potential to have to re-zero and then introduce variance into your 100 round loading session. Even masking tape can help you here if you don't want to screw it to the table/bench.

3. Always see the plane of the level marks the same way every time. Get a usb camera and hook it up to your computer. Level the camera into a fixed position relative to the scale's level mark so it cant move the relationship. If it moves, your screwed. A different viewing angle will change the charge weight relative to prior rounds loaded. This is true as well for people simply moving their head up and down or shifting side to side while weighing charges. The magnified close up view makes seeing movement of the scale and level much less challenging and you never move position. Easier on your eyes, neck and back as well.

4. Always level to charge weight in the same direction. I always want the charge to move up to the level line the same way every time. If I overcharge, I dump a little out and then re-trickle up again. I can't say that this is a real improvement, but I feel better doing it this way. I don't drop the pan on the scale so it jumps up and then swings down. Place it on the scale and allow it to gently move up until it stops below the level mark.

5. If you use a small, light table and not a fixed bench or table, don't bump it. You might move the table or the camera or the scale. That puts us back to the beginning.

Sounds like a lot, but once it is set up, you never have to doubt your consistency because you have removed human interaction variance. It costs nothing other than perhaps some hardware and the $12 usb camera you probably already own.

 

[Fulzgold]

I have an old M5 that I tuned myself (probably not to the same level that Scott does). I added a need to the indicator side, rebalanced the pan holder, and sharpened the knife edges. IT still has some nuances that I have to deal with, but it is VERY accurate and reliable.

Who is Scott Parker?