• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Balance beam scale maintenance

Those of you using balance beam scales, DONT FORGET TO MAINTAIN YOUR SCALE. I was dealing with really sporadic measurements on my Lymann M5 today, so finally I took off the beam and reburnished the knife edges with a graphite stick. Huge difference! the scale was far more reactive and after zeroing the scale again my measurements were coming out spot on once again.
 
mao,

Boyd Allen had a thread on tuning up a used 5-0-5 scale he bought online. Do a search and you'll find it. He did other things, but one I've done so far is to use Teflon tape on the zero adjuster foot screw. Took out all the play.

Dennis
 
Thats one i havent heard of, teflon tape on the zero screw. I did do a little tuning on my lymann M5. Added a needle to the indicator, re-balanced the pan holder. sharpened the knife edges. Nothing much, but its definitely more accurate than my Hornady digital scale.
 
I have an RCBS (OHAUS) 304. Are you using the teflon tape because there was PLAY in the zero adjuster? Not that mine needs readjusting but that screw (if I am thinking of the same thing) on mine is relatively stiff to turn. I've done nothing to the scale except keep dust off the beams, and when I do check it (against two electronic scales and 3 certified weights) it checks fine. The age has me wondering what I should do as I've had this over 30 years.
 
If its still checks well with check weights and against more accurate scales then Id say you are good to go. You may check out the knife edges just to see if they need sharpening. You shouldnt see any shiny spots when you look straight at the edge.
 
Thanks for thoughts and tips guys...I have an Ohaus 5-0-5 that I like very much too but it needs tune up occasionally.
 
mao0720 said:
I took off the beam and reburnished the knife edges with a graphite stick.

Can you elaborate a little? What's a graphite stick and how did you burnish the knife edges with one?

Thanks
 
I would like an answer about that too. My Redding sticks and the company said it would have to be returned for safety reasons.

Thanks
 
Go down to the local art supply shop and get a graphite stick (like a pencil but with no wood). I use a pretty soft graphite, like B2. Rub the graphite stick on your knife edges, until they are well coated. Use canned air to blow off any excess graphite.
 
IMO, the basics of scale tuning involve several steps. First of all, it is a good idea to adjust your scale pan holder weights so that when the scale frame is perfectly level, the beam indicates that the scale is in balance. The design of the 5-0-5 makes this difficult. For those, I put a small level across the top of one of the agate retainers. The next thing that I usually do is remove the agates that the knife edges sit on (this would be unique to Ohaus Lyman and RCBS) and clean the socket and all sides of the agates with alcohol and a Q tip. The last time that I did one, I used a Dremel type tool and a small cotton buffing wheel, without any abrasive to work on the agate's V, where the knives rest. I also polished the faces of the knife edges a little the same way, being careful not to blunt the edges. Most of the scales that I have worked on needed to have their knife edges tuned up. I use a diamond lap for that, and then polish with a fine stone, and deburr the edge with a small piece of wood. The steel is not very hard. One thing that I have noticed is how edges can become dulled by how the scale is assembled. It is very easy to hit one of the agate retainers with a knife edge when placing the beam. Recently I have been putting in one end of an edge, running it over to the retainer, holding it there, and carefully dropping in the other edge. Another area to look at is the wire bail that supports the pan holder and rides on its own knife edges. I spread that piece so that it cannot shift , but not so much that it rubs excessively, just a close fit. I usually take it off open it up, put it back on, and then carefully close it a little to get the fit that I want. Each time that I set up a scale, I lift the entire pan assembly by pinching the holder hook just below the bail, and lifting the assembly a little and setting it down so that the knife edges are at TDC of the wire circles that they support. I also shift the beam so that the ends of the main knife edges are not rubbing. The last scale that I did a little tuning on was my recently purchased RCBS 5-0-5 and it now will deflect a little for each piece of Varget that I place in the pan, moving half the width of the balance reference line for one piece, five equaling a tenth of a grain.
 
That's all good advice Boyd, a beam scale, when set up properly and in good trim should be repeatable and sensitive enough to detect a single kernel of something like Varget powder.

I find they are very little effected by strip lights and other electrical interference, they don't tend to drift, they don't need half a day to warm up and, as long as they're not abused they will outlive the user. :)

You can check here to see my beam scales in action:
http://bulletin.accurateshooter.com/2011/05/forum-member-rigs-video-display-for-balance-beam-scale/
http://bulletin.accurateshooter.com/2012/07/monitor-balance-beam-with-magnified-image-on-smartphone/
 
Thanks Boyd and 1066 I have been wanting to do a little tune-up and maintenance on my ohaus 1010, now I have a check list and a couple of vids to guide me.
 
mander said:
are there any videos showing scale tuning ? I could not find any on youtube or this site.

Here's a couple that might give you some ideas.
https://www.youtube.com/watch?v=gTElTMWgc3Q

https://www.youtube.com/watch?v=bVtYglAd9Dc
 
wmdron said:
Thanks Boyd and 1066 I have been wanting to do a little tune-up and maintenance on my ohaus 1010, now I have a check list and a couple of vids to guide me.

This is an old 10/10 in race trim.



and an old Hornady/Pacific



cleaning up the bearing housing:



RCBS level adjuster:
 
My Ohaus is an ebay find and it has required a bit of tweeking. I know there are some good scale tuners out there,but I want to do it myself. Some time ago I stoned the knife edges and today I cleaned and polished them with a dremel buffer wheel attachment and alcohol. Cleaned and polished the agates again with dremel, no compound or anything just alcohol and buffing wheel at slow speed. Adjusted the hanger wire to take out any play and also cleaned and polished the edges where the hanger wire rides. So I would like to install some padding to take out the "clunking" noise when removing and replacing the pan. I am perfectly happy with the results I have been getting and can't imagine buying an electronic unit when I can get these kind of results with a balance beam. Thanks again for the tips and vids
 
Another thing I always do is glue a piece of needle to the indicator on the beam. I make sure it overlaps the zero marks on the scale body, that way you dont have to try to line up two course lines with a space in between them. Of course, do this before you adjust the weight in the pan holder.
 
This needle thing sounds like a very good thing. I do have a question, if you do install a needle to act as a pointer can you not then just readjust the scale to zero using the needle as the pointer? Or is there a little more to it than that?

RS
 
Hombre0321 said:
This needle thing sounds like a very good thing. I do have a question, if you do install a needle to act as a pointer can you not then just readjust the scale to zero using the needle as the pointer? Or is there a little more to it than that?

RS

Adding an extended pointer is really worth while if you are going to use a webcam or smart phone, it eliminates all parallax error and magnifies any movement about a hundred fold.

If you do add a pointer you will need to add weight to your scale pan. If you have a quick look at this video I show you how to reset the zero with scale pan weights.


https://www.youtube.com/watch?v=HOKJxe0FUTk

 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,871
Messages
2,205,026
Members
79,174
Latest member
kit10n
Back
Top