I am relatively new to this hobby but one of the bigger mysteries I have run into is the size of the holes in 1-2-3 blocks. The ubiquitous blocks often come with 5 holes tapped with 3/8ths by 16 threads and 18 untapped holes. At first glance it looked like the perfect, well thought out solution by suggesting the blocks could be fastened together in many ways to resolve almost any setup issue.
Then I discovered that the 18 holes are drilled at the 3/8ths by 16 tap size and not the 3.8ths clearance size … effectively rendering the holes useless unless as a 3/8ths bolt would not fit thru the holes. Note that I understand why the manufacturing shortcut was taken … it costs more to drill two different size holes … but I still had to wonder if anyone that provided the design and cost specifications for the blocks ever actually uses them.
Ideas of how to make the 1-2-3 blocks useful went thru my head … not of them any good. Drilling the hardened blocks is not an option. A threaded insert could be put into the existing threaded holes to allow 5/16ths bolts to be used. Yes a solution but I would think unkind thoughts about the designer\manufacturer every time I had to use them. I had seen an article in HSM [I think] about making a set of 5/16ths rods and bolts to hold them together. It would make a great “first project” but it was at best a great answer to a problem that did not need to exist.
After spending much time searching for 1-2-3 blocks on the web and calling many vendors I have finally discovered someone who has “usable” 1-2-3 blocks. Micro-Mak … a small tools specialist mostly know for addressing the needs of model makers … has 1-2-3 blocks that have the 18 untapped holes drilled at 3/8ths clearance size … http://www.micromark.com/precision-1-2-3-blocks-economy-version,9551.html. What is interesting is that the economy version is drilled in what I consider the correct manner and the upscale Ultra Precision version is the unusable “all 3/8ths tap size” pattern.
So if you are looking for “non ultra precision but usable” 1-2-3 blocks you now know where to get them.
And if anyone can explain to me why all of the other 1-2-3 blocks that I have queried about have what I consider the wrong size holed in them … other than the cost to manufacture argument I have already given … please educate me. I am hoping there is a very good "so you can do this with them" explanation because I cannot believe the world is filled with millions of incorrect blocks
Arvid
p.s. One more thought came to mind. In the beginning an "incorrect block" was made. After that it was simply cloned by every other manufacturer and none of them thought to try to improve on the original design.
Then I discovered that the 18 holes are drilled at the 3/8ths by 16 tap size and not the 3.8ths clearance size … effectively rendering the holes useless unless as a 3/8ths bolt would not fit thru the holes. Note that I understand why the manufacturing shortcut was taken … it costs more to drill two different size holes … but I still had to wonder if anyone that provided the design and cost specifications for the blocks ever actually uses them.
Ideas of how to make the 1-2-3 blocks useful went thru my head … not of them any good. Drilling the hardened blocks is not an option. A threaded insert could be put into the existing threaded holes to allow 5/16ths bolts to be used. Yes a solution but I would think unkind thoughts about the designer\manufacturer every time I had to use them. I had seen an article in HSM [I think] about making a set of 5/16ths rods and bolts to hold them together. It would make a great “first project” but it was at best a great answer to a problem that did not need to exist.
After spending much time searching for 1-2-3 blocks on the web and calling many vendors I have finally discovered someone who has “usable” 1-2-3 blocks. Micro-Mak … a small tools specialist mostly know for addressing the needs of model makers … has 1-2-3 blocks that have the 18 untapped holes drilled at 3/8ths clearance size … http://www.micromark.com/precision-1-2-3-blocks-economy-version,9551.html. What is interesting is that the economy version is drilled in what I consider the correct manner and the upscale Ultra Precision version is the unusable “all 3/8ths tap size” pattern.
So if you are looking for “non ultra precision but usable” 1-2-3 blocks you now know where to get them.
And if anyone can explain to me why all of the other 1-2-3 blocks that I have queried about have what I consider the wrong size holed in them … other than the cost to manufacture argument I have already given … please educate me. I am hoping there is a very good "so you can do this with them" explanation because I cannot believe the world is filled with millions of incorrect blocks
Arvid
p.s. One more thought came to mind. In the beginning an "incorrect block" was made. After that it was simply cloned by every other manufacturer and none of them thought to try to improve on the original design.
