Tuned RCBS 505 scale. The RCBS 505, 502, and 10/10 are no longer made. They have been replaced by the RCBS M500 and M1000 scales. This scale is one of the last 505 produced, made in China.
I'd love to see a video of the actual tuning process. For example, showing how you install the extended needle, and showing how you polish the bearings. Thanks for the great content!
Thanks for sorting these Allan, very much looking forward to using the revamped scales. Amazing what you've done with a frankly average original set of Chinese 505 scales.
Allan, Thanks for the video. Could you provide some more detailed information on the cameras you use please? Make and model number if possible. Thank you.
As usual, you have some very nice equipment. Could you include the exact camera model, what it is you did to the balance beam contact points, what you used for filler under the scale. I am sure many of us would like to know all these things. Thank you and congratulations on your wonderful modifications. Dave & The Girls
Nice job on your scale tuning. I am starting to use a video camera like you. I am currently fabricating a webcam mount to attach the camera to my reloading bench. My first attempts at scale tuning did not result in the kind of results you get. I bought a used Lyman M5. I have replaced the old Agate bearing with new ones from RCBS from a 505 scale. I have repaired, tuned and adjusted the wire pan support, as it was bent when I got it. I adjusted the stirrup/hanger that the pan hangs from. I have adjusted the knife edges with a stone and then cleaned them with alcohol. I cleaned the new bearings and the bearing pockets with alcohol before reassembly. I have cleaned the scale overall. I cleaned the knife edges. I have also adjusted the pan weights so that the scale reads zero when the scale has been leveled with a small level. Everything repeats perfectly with and without a weight in the pan. The problem comes when you zero the scale, then move the large poise to say, 50 grains to check it with the check weight then move the poise back to zero. When you do that, the scale often no longer is registering zero according to the beam and scale registration mark. Usually it can be off only 1/2 or less than 1/2 of the 1/10 grain registration marks, though sometimes it can be off by a full mark. I do notice that my beam oscillates a lot less than yours do. My magnet dampening seems a lot stronger and I wonder if the magnet strength could be an issue. My scale seems to now be easily one kernel sensitive. The only problem remaining is the return to zero issue when the large poise is set back to zero.
Hello Danny - Sounds like you're getting in there and willing to have a go. The M5 is a good scale, I wouldn't worry about a bit of over damping, it shouldn't be contributing to your problem in any way. The first thing I would do is have a very careful inspection in the damper slot, with a torch, look for any tiny hairs of wire wool that have been attracted to the magnets. It's quite a common problem that's often overlooked. Get an eyeglass and have a look at the "0" notch on the beam, make sure there are no burrs or debris there and that the little washer on the main poise sits in the notch cleanly. Centre the beam up in the bearing so the points of the knife edge don't touch the end plates and try the scale. If the knife edge is not completely flat right to the tip it will cause a problem. instead of pivoting around a single point the tip will describe an arc on the endplate, again causing friction.
Thanks for the help. I had to clean this scale up with some mild soap and water because it was so dirty. I cleaned in the damper blade slot, but I am going to go over that again like you describe, to make certain. I was a bit frustrated when posting, because I had sharpened the knives and did not see any reduction of the issues with the inability to repeat the scale zero. After posting, I tried this beam in my perfectly behaving RCBS 505 scale body casting and found the same behavior as the complete M5, so I figured that the issue still must be in the beam. I sharpened the knife edges more and found that I had eliminated most of the wild zeroing errors, and it is now pretty much within the realm of acceptable, but I am now sure I can get better. Stoning the knife edges has been a bit slow because I have been forced to make do with a too fine stone, but the results have been good. I may have the issue that you mentioned with the end of the knives, but I will have to clarify that in another post. It was something I noticed before you mentioned it, but I did not know if it was an issue.
I figured out what you meant by the knife edges being flat. Originally, I had wondered if the poise detent washer screw could be loose, causing errors. I stoned a bit on the knife edges and got things a bit better. I will have to examine the poise zero notch to see how it looks.
Sounds like you're making progress Danny - Here's sketch I made of how the knife edges should look. img.photobucket.com/albums/v639/allan1066/Knifeedges.jpg
Thanks for the help, I first was thinking that the bevel on the ends of the knives might have been what you were referring to, until I re-read your description, and then confirmed by your great and thoughtful diagram. Based on what I have found in this scale, I would not be surprised if it had issues right from the factory. Everything on the scale looked to be factory original parts as best as I can tell. What I found is that the beam/pan was not properly weighted/balanced/leveled to the scale (which I fixed), the agate bearings had some factory grinding flaws which showed up as being multiple facets in the V, which should obviously be only one continuous machined surface on each side of the V. I replaced those with new agates, and as you know, I have slowly been stoning the knives. So far, nothing I have done has resulted in anything bad, and in fact, as mentioned, the scale is nearly there. I have only a little cleanup stoning to do, and one more unusual factor to address. I notice that the copper damper blade is so close to the back of pocket in the little magnet casting that any movement of the scale beam other than absolutely straight up and down causes the damper to bump the scale body, which probably bumps the agates out of position, which can't be good. Right now, I just don't know why it is bumping. I have to get my Ohaus brand (the grey ones) 10•0•05 out to compare and find out. I loosened up the little screw underneath that holds the agate support casting to the scale, then rotated the casting counter clockwise to move the back edge of the damper away from the scale, then retightened. It was not a complete fix, but it helped. Right now, I am contemplating on grinding or milling some of the back edge of the damper. I don't think that the miniscule amount I might remove would alter the damping function, but I will hold off on this. When I replaced the agates, I found what appeared to be old oil flooding the agate pocket area, which makes me suspect that somebody was trying to "fix" something.
Very nice enhancements! Adding the webcam is a fantastic idea. I also use a 505 scale. Could you tell me where I can purchase a similar foot adjustment knob as you put on this 505?
Hello Matt. The bearings on the RCBS scales are mad from Agate, a very hard stone. If you unscrew the retaining plates you can lift out the bearings. The shouldn't need a polish but they do need to be absolutely clean and grease free. I scrub them with a tooth brush with auto brake cleaner or other spirit. When replaced they need to be free to wobble about a bit.
Here's a couple of free ones that work with most cameras -. www.sharpcap.co.uk noeld.com/programs.asp?cat=video and if you want to run on an android tablet. play.google.com/store/apps/details?id=com.vaultmicro.camerafi
Hi. Just found this video. Really great video. You mentioned a ball bearing on the end of the adjustment rod. If I understood correctly, you made the adjusting pieces. Would like to do the same for mine. How did you add the bearing/what kind of bearing, etc. I am a machinist by trade, home machine shop as well. Making is very doable. Thanks
Thanks for the interest Carl - I'm just a self taught scratcher with a home shop so you wouldn't have any trouble making one. The easy way is to grab a length of threaded rod, centre drill the tip and drill in to a depth of just over half the diameter of the bearing you will be using. In my case, I have some 4mm balls scavenged from and old bearing. I use a dab of loctite, push the ball in, then thread and machine a separate cap. Check my other videos - I've made several different types.
Almost any USB camera will do Christian, the only requirement is that it has a manual focus. This is the one used in that video. www.ebay.co.uk/itm/USB-2-0-5-Megapixels-Retractable-Mini-Clip-WebCam-Web-Camera-For-PC-Laptop-Use/282801656018?hash=item41d84ad0d2:g:Fc0AAOSw61haUzf-
Almost all reloading scales can be used straight out of the box, and most will stay within the +/- 10th gn standard - But- what if you want/need better? Many long range target shooters are spending a small fortune on digital scales that resolve to better than a single kernel, a good tuned scale will do that for less than a quarter of the cost of a digital, and still be doing it in 20 years time, long after the digital in in the bin. I've just been chatting to a chap in New Zealand who is loading 1.4 gn in a .32 Pardini target pistol - You can't measure those low loads accurately and +/- 10th is not really good enough.
I have bought a cheap camera and am using the app. Picture quality is not as good as yours, so what actual camera do you have from eBay as they obviously vary. What about using Bluetooth cameras to get rid of the cable! Have you tried them?
Hello Roger - Are you sure you have it focused ok? To get good picture quality down to a couple of inches you will need a camera with a manually adjustable lens. You will need to screw the lens out for close focus.This is the camera I use:www.ebay.co.uk/itm/Mini-Black-Cube-USB-5-MP-PC-Camera-Webcam-For-Laptop-/151945594366?hash=item2360a9c5fe:g:UxMAAOSwKtlWkoNk
+thetargetmaster Coincidently I tried the camera again and spent some time with the focus, with much better results. I bought a mahogany cased analytical beam balance for a massive £2.20 to experiment with! It has four agate knife edges that rest on four agate flat planes. Very repeatable readings and good fun to experiment with! Must have cost a bundle back in the day. Did I mention Two pounds twenty pence?!!
