Beam scale mod courtesy of Boyd Allen

[swadiver]

Just wanted to give a shout out to Boyd Allen. I have mint condition from 1971 Ohaus 10-0-5 beam scale accurized by Scott Parker. it was working very good, but i felt it could be a bit more repeatable.

I saw an old thread, I believe on Bench Rest Central discussing accurizing beam scales. Boyd added a number of suggestions including the application of pencil lead from a mechanical pencil to the knife edge pivots of the beam. i applied this mod and did quite a bit of testing with the Ohaus and a digital scale and found the repeatably of the Ohaus greatly improved by this simple mod. for now, i am holding off on my purchase of a higher end digital scale. i use the Bald Eagle digital in conjunction with the Ohaus. i find the bald eagle to be very good when it is not drifting.

thanks Boyd!

 

[6MMsteve]

Do you make the graphite from a pencil or do you buy it. not familiar with pencil led graphite

 

[swadiver]

Boyd said to use a mechanical pencil lead. i assumed it contains graphite, but i don't really know. whatever it's made of, it's working very well

 

[gotcha]

Thanks for the tip swadiver !! I imagine a good old #2 wood pencil would work just as well. Scrape the lead with an x-acto knife for just a smidgeon of powder on the agates. Haven't tried it yet but you can bet I will .... Makes me wonder if motor mica might work just as well. Anyone else have input ????

 

[rebel]

Great Idea! You can by powdered graphite in a tube at most hardware stores. I have some I use to lube tumblers on locks with.

 

[nmkid]

Thanks for the tip swadiver !! I imagine a good old #2 wood pencil would work just as well. Scrape the lead with an x-acto knife for just a smidgeon of powder on the agates. Haven't tried it yet but you can bet I will .... Makes me wonder if motor mica might work just as well. Anyone else have input ????

I've used motor mice before and it seemed to build up and form the slightest of a crust(?) Maybe I was using too much?!

 

[BoydAllen]

I am glad that your scale works better. To clarify, I did not recommend putting powdered graphite on the agates that support the knife edges. This is what I wrote."Clean and don't oil the agates that the knife edges sit on. Sharpen the knife edges so that when you look straight at the edge there are no visible shiny spots, and then burnish the edge with the side of a mechanical pencil lead." The main thing is that the knife edges be sharp, and that the sharpening be carefully done. I take care to maintain the angles as best I can, and take the same number of strokes on all sides of both edges. This sharpening is the main issue. Your agates should remain clean and dry. In the last few months I have had more than one conversation with a shooter who wanted his scale to work better. It has bee fun helping them. Of course the real expert is Scott Parker, who has tuned a large number of scales to an amazing level of performance, considering what they cost and where they started when new out of the box.

 

[gotcha]

I've used motor mice before and it seemed to build up and form the slightest of a crust(?) Maybe I was using too much?!

Yep, using too much could be a problem. Also, you live in a super dry area. I wonder if high humidity here in the steamy S.E. would cause any of the powdered lubes (including graphite) to turn to goo by absorbing moisture ??? How 'bout it swadiver, did you have any problems with goo? Do you live in a dry climate?........... Just wondering OOPS !! Boyd straightened it out while I was typing

 

[swadiver]

I am glad that your scale works better. To clarify, I did not recommend putting powdered graphite on the agates that support the knife edges. This is what I wrote."Clean and don't oil the agates that the knife edges sit on. Sharpen the knife edges so that when you look straight at the edge there are no visible shiny spots, and then burnish the edge with the side of a mechanical pencil lead." The main thing is that the knife edges be sharp, and that the sharpening be carefully done. I take care to maintain the angles as best I can, and take the same number of strokes on all sides of both edges. This sharpening is the main issue. Your agates should remain clean and dry. In the last few months I have had more than one conversation with a shooter who wanted his scale to work better. It has bee fun helping them. Of course the real expert is Scott Parker, who has tuned a large number of scales to an amazing level of performance, considering what they cost and where they started when new out of the box.

thanks for clarifying, Boyd. Scott had done all the other work, I just did the pencil thing as you stated and am happy with the results

 

[BillPa]

After cleaning I use colloidal graphite(Lock-Ease) applied with a fine tip paint brush on the center balance knife shafts, the bottom of the agate blocks, the pan support knife shafts, it's loop and the "hook' on the pan support. I'll put a drop or two on a piece of paper, allow the carrier to flash off then dip the brush the remaining graphite.

Bill

 

[Brians356]

burnish the edge with the side of a mechanical pencil lead.

Boyd, is that to literally burnish (polish) the edge? Or just to apply the graphite?
-

 

[swadiver]

wondering what the pencil lead is doing. acting as a dry lubricant and also filling in the microscopic voids in the knife edges?

also, i assume from time to time one will still need to clean the knife edges and the surfaces where they sit on the scale with the usual non residue type cleaner and then reapply the pencil lead?

 

[swadiver]

Boyd, is that to literally burnish (polish) the edge? Or just to apply the graphite?
-

i just rubbed the side of the pencil lead along the knife edges and then gently blew off some residual.

wish i had found this info earlier. i am just finishing loading 500 + .308 rounds for the World's in Ottawa next week and this would have saved me some aggravation

 

[BoydAllen]

If anyone wants to discuss working on his scale, you can PM me and we can go from there. The hardest part is sharpening the knife edges and that is not all that difficult if you take your time and are careful. There are other things that need attention as well. I have been able to get my scales to return to zero, and repeat when weighing the same weight, as well as show much better sensitivity. If a scale is off by a couple of tenths, as long as you use the same scale for all of your reloading, I do not think that it matters much. For the very best result I recommend getting a hold of Scott Parker, and not being in a hurry, since this is a sideline and he has other responsibilities that keep him busy, as well as quite a bit of demand tuning scales.

 

[500Stroker]

I also would like to send a shout out to Boyd as he helped me with the fine tuning of my scale. I can highly recommend the diamond dust files that Boyd uses for truing the knife edges. I picked up a set of three for $25 on ebay.

 

[BoydAllen]

I also would like to send a shout out to Boyd as he helped me with the fine tuning of my scale. I can highly recommend the diamond dust files that Boyd uses for truing the knife edges. I picked up a set of three for $25 on ebay.

Thanks. Which grit worked the best for you?

 

[500Stroker]

Thanks. Which grit worked the best for you?

I used the Fine grit first and then finished with the Super Fine grit.
Thanks again

 

[centershot]

For "aging" eyes, I super glued a strand from a stainless steel brush to the end of the balance beam to extend the pointer. Much easier to see it on the graduated part. Then take the pan apart and remove a small piece of shot to re zero the scale.

 

[swadiver]

For "aging" eyes, I super glued a strand from a stainless steel brush to the end of the balance beam to extend the pointer. Much easier to see it on the graduated part. Then take the pan apart and remove a small piece of shot to re zero the scale.

i did the $5 E Bay webcam attached to a cheap tablet computer. works awesome, but increases the clutter.

 

[painter]

Thanks to all, worked on my two M-5 lyman scales, they are so much better, it is nice of others to share info. thanks again, Painter