Josh.Sampson Posted January 31, 2022 Share Posted January 31, 2022 Some Golden Means Calipers I just finished up. Actually took some progress pics on this one. Quote Link to comment Share on other sites More sharing options...
Ridgeway Forge Studio Posted February 23, 2022 Share Posted February 23, 2022 That is some top level work. And the precision involved is beyond my understanding. Kudos for the good work and thank you for the process photos- this would make a great blueprint. Quote Link to comment Share on other sites More sharing options...
anvil Posted February 23, 2022 Share Posted February 23, 2022 Another person who uses a square ended center punch. No wonder they came out so nice. Quote Link to comment Share on other sites More sharing options...
Josh.Sampson Posted March 14, 2022 Author Share Posted March 14, 2022 On 2/23/2022 at 9:20 AM, Ridgeway Forge Studio said: That is some top level work. And the precision involved is beyond my understanding. Kudos for the good work and thank you for the process photos- this would make a great blueprint. Thanks you very much. I just started another pair but instead of the Golden Mean they will measure the center point. The center will be in the middle of the lowest rivet so I plan on making that rivet from tool steel and leaving enough on one side for a point to use as a Center punch. I’ll post pics when I finish them. Haven’t done good on progress pics with them though. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted March 14, 2022 Share Posted March 14, 2022 For square bar stock a nifty center finding tool is to take a short section of sq stock and put 3 small rods equally spaced in it. The two outer ones are long enough to ride the sides of your stock being marked and the center one being a hardened scribe. To use you drop it over the stock and rotate till both the ends are riding on opposite sides of the stock. The center one will be the center; just pull along the stock with the outer pegs riding on the sides to mark. This type will also do a variety of sizes of stock. ||____|____|| Quote Link to comment Share on other sites More sharing options...
Frazer Posted March 14, 2022 Share Posted March 14, 2022 A fun piece. Thanks for sharing Josh. I need to work the rivets a little more to get the full ROM.. Close enough, though slightly off. At fully closed I get a ratio of 1.68. At "fully open", 1.64. I can probably file the tips to clean them up and get a better line. These are as forged. Quote Link to comment Share on other sites More sharing options...
Goods Posted March 15, 2022 Share Posted March 15, 2022 Josh, how about cutting the center marker at the rivet. Then have a punch with slots riveted in between the pivot joints. That way the punch is always centered, but can slide in and out to mark central easily on a wide range of widths. Could take a couple different versions/tries to make it work… Did you make it to Kevin’s last weekend? I had other commitments… David Quote Link to comment Share on other sites More sharing options...
JHCC Posted March 15, 2022 Share Posted March 15, 2022 There's another kind of center-finder I've seen (but alas, have not yet been able to find a photo of) that are basically a pair of calipers that you adjust to the width of your piece, and then slide a pin down the middle to mark the center. Because the pin guides and the pivot points of the calipers form a rhombus, the pin itself is always pointed directly at the midpoint between the caliper tips. Quote Link to comment Share on other sites More sharing options...
Frazer Posted March 15, 2022 Share Posted March 15, 2022 I was thinking of changing the ratio to 1:2 and adjusting the long side to the length of the stock then using the short side to find the center. Quote Link to comment Share on other sites More sharing options...
JHCC Posted March 15, 2022 Share Posted March 15, 2022 That would certainly work very well. Quote Link to comment Share on other sites More sharing options...
Frazer Posted March 16, 2022 Share Posted March 16, 2022 For folks who aren't confident that they can forge this style a pair of golden means calipers, they can be made with flat stock and minimal forging. The measurements given in Josh's picture 7th from the bottom are all you really need and can serve as a reference. They can also be changed as long as you follow the proper ratio. I made a doodle that may help. The ratio can be changed to something else (1:2 for example) as follows: Granted you could also make a set of X shaped proportional dividers if you want to divide into 3rds, quarters, etc. with the same tool... but that's less fun. Quote Link to comment Share on other sites More sharing options...
JHCC Posted March 16, 2022 Share Posted March 16, 2022 One thing to note is that consecutive Fibonacci numbers converge on the Golden Ratio. You can therefore get a pretty good proportion without bothering with decimals by replacing "a/Φ", "a", and "b" in the first sketch with three such numbers (such as 13, 21, and 44 34) and then picking a sufficiently small unit of measurement (such as 1/4") that your dividers aren't too enormous. Quote Link to comment Share on other sites More sharing options...
Frazer Posted March 16, 2022 Share Posted March 16, 2022 I'm guessing you meant 34 not 44. i.e. 34/21 = 1.619 Now I have Lateralus stuck in my head. Quote Link to comment Share on other sites More sharing options...
JHCC Posted March 17, 2022 Share Posted March 17, 2022 Yes, that's right; sorry. Quote Link to comment Share on other sites More sharing options...
JHCC Posted March 17, 2022 Share Posted March 17, 2022 On 3/16/2022 at 2:53 PM, Frazer said: Granted you could also make a set of X shaped proportional dividers if you want to divide into 3rds, quarters, etc. with the same tool... but that's less fun. I beg to differ; the pair of adjustable proportional dividers I got a couple of months ago is a LOT of fun: These have one scale for setting up divisions of a line into equal segments and another for dividing the circumference of a circle, the last being particularly handy if you want to make, say, a seven-pointed star or a five-branched candelabra. Quote Link to comment Share on other sites More sharing options...
Josh.Sampson Posted March 19, 2022 Author Share Posted March 19, 2022 On 3/14/2022 at 6:35 PM, Frazer said: A fun piece. Thanks for sharing Josh. I need to work the rivets a little more to get the full ROM.. Close enough, though slightly off. At fully closed I get a ratio of 1.68. At "fully open", 1.64. I can probably file the tips to clean them up and get a better line. These are as forged. Very nice! You can definitely do some fine tuning with it cold. On 3/14/2022 at 9:14 PM, Goods said: Josh, how about cutting the center marker at the rivet. Then have a punch with slots riveted in between the pivot joints. That way the punch is always centered, but can slide in and out to mark central easily on a wide range of widths. Could take a couple different versions/tries to make it work… Did you make it to Kevin’s last weekend? I had other commitments… David I started on the center punch style at Kevin’s. Just finished them up last night at Steve King’s. I’ll send you some pics and maybe post some here. The sliding center pointer idea did come up but I like that I can mark the center easily with them. On 3/16/2022 at 2:53 PM, Frazer said: For folks who aren't confident that they can forge this style a pair of golden means calipers, they can be made with flat stock and minimal forging. The measurements given in Josh's picture 7th from the bottom are all you really need and can serve as a reference. They can also be changed as long as you follow the proper ratio. I made a doodle that may help. The ratio can be changed to something else (1:2 for example) as follows: Granted you could also make a set of X shaped proportional dividers if you want to divide into 3rds, quarters, etc. with the same tool... but that's less fun. Correct. You can change the ratio to anything you want and the bends are mostly aesthetic. The most important part is all of the ratios working out correctly. I’m going to post a center punch pair I just finished up. Quote Link to comment Share on other sites More sharing options...
Frazer Posted March 23, 2022 Share Posted March 23, 2022 On 3/17/2022 at 4:03 PM, JHCC said: proportional dividers Not quite as fancy as yours John, but here's a set of home brewed dividers. They're limited to 2, 3, 4 and 5 to 1. Quote Link to comment Share on other sites More sharing options...
JHCC Posted March 24, 2022 Share Posted March 24, 2022 More robust for scaling up from a drawing in the shop. Quote Link to comment Share on other sites More sharing options...
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