1 2 3 blocks

I have a pair of Suburban Tools 1 2 3 blocks and they are very well made. They can be bolted in various configurations, and the important part,
is that they are matched and well ground. Very flat and square and to each other and hardened. I bought them new for a great price. I've never seen Renzettis blocks up close but I'm sure their great. He is very dedicated machinist. I have to disagree Bob Korves. The ST blocks are among the best I've seen. Moore Tools makes an excellent 1 2 3 block. B&S are so so, but bolt together. The ST value line, for $35/pair, are good enough for some set ups., but don't bolt. Better than many other cheap import blocks.

Suburban Tools 1 2 3 matched
Model #B-123-NH-M at $105/pair, with no holes can be drilled and tapped to any configuration. Very accurate, hardened. Costs less than the other ST precision 1 2 3 with holes. Ground and HT'd.


Starrett 1 2 3 blocks are very high quality, but very expensive. Mitutoyo also has 1 2 3 blocks. I'm sure they're well made but have never had them in my hands. Renzetti blocks are not commercially available but show a very good design. I agree with Bob. For a hobbyist to make a set of 123 blocks takes time, careful work, and a lot of equipment, and heat treatment. Then, inspected properly to know what you have.
 
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I have a pair of Suburban Tools 1 2 3 blocks and they are very well made. They can be bolted in various configurations, and the important part,
is that they are matched and well ground. Very flat and square and to each other and hardened. I bought them new for a great price. I've never seen Renzettis blocks up close but I'm sure their great. He is very dedicated machinist. I have to disagree Bob Korves. The ST blocks are among the best I've seen. Moore Tools makes an excellent 1 2 3 block. B&S are so so, but bolt together. The ST value line, for $35/pair, are good enough for some set ups., but don't bolt. Better than many other cheap import blocks.

Suburban Tools 1 2 3 matched
Model #B-123-NH-M at $105/pair, with no holes can be drilled and tapped to any configuration. Very accurate, hardened. Costs less than the other ST precision 1 2 3 with holes. Ground and HT'd.


Starrett 1 2 3 blocks are very high quality, but very expensive. Mitutoyo also has 1 2 3 blocks. I'm sure they're well made but have never had them in my hands. Renzetti blocks are not commercially available but show a very good design. I agree with Bob. For a hobbyist to make a set of 123 blocks takes time, careful work, and a lot of equipment, and heat treatment. Then, inspected properly to know what you have.
To be clear, Emilio, I am sure the Suburban made 1 2 3 blocks are very good and accurate, as are all their in house made products that I am aware of, just very expensive for home shop guys on a budget. It is the value line that I am not so sure is worth the extra money for the Suburban name on import blocks, though I have no real knowledge of them. Also, when I speak of bolting together, I mean solidly and easily bolting together, with no protruding fasteners in the way anywhere -- all faces fully useful. The Renzetti blocks do that.
 
The ST USA blocks all bolt together with no protrusions with set screws and 5/16-18 SHCS and they sit below the large Csnk holes.
The ST no hole 1 2 3 blocks can be purchased and you can drill and tap in any configuration. I can bolt the ST blocks in any way w/o protrusions. I don't see any difference between the Renzetti blocks and the ST blocks. The ST hole/tapped hole configuration is well designed. This in no way takes anything away from either. Besides, I don't think you can buy his blocks. I was just curious as to what, if any advantage, one had over the other. Not everyone has the time or tools to make a good matched set of 1 2 3 blocks. I don't. I currently don't have a need to make 1 2 3 blocks into a Lego style set up. I use them in very basic ways. If I ever get a surface grinder, I may consider making a set of blocks. For now, I only use them one or two at a time., mostly un-bolted together.
The use of 82° flat head socket screws cannot be used.I don't know if the Renzetti blocks can.12354_HDR.jpg
 
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I made a pair of 123 blocks when I was an apprentice (while no one was looking) I used O-1 tool steel and drilled them for lightness on the 2X3 faces only and heat treated them myself, probably stuck them in with another job. I then ground them as best as I could with the shop's only surface grinder, a 16 X 72 Mattison as best as I could, as close as I could; they have served me well over the 50 years or so since I made them; I have a coupe of other sets, some have tapped holes, some not. I have never felt the need to bolt them together, I have angle plates for that.
I also made a couple of sets of parallels, and drilled them for lightness, perhaps a mistake in at least one way; they were never ground to nominal size, so after I got a surface grinder (without coolant so far) I tried to grind them to size; this proved nearly impossible because the holes acted as insulation in the center, not being able to dissipate heat as well as if they had been solid, they arched up when heated by the grinding process and I was not able to grind them parallel; coolant would have prevented this.
 
The ST USA blocks all bolt together with no protrusions with set screws and 5/16-18 SHCS and they sit below the large Csnk holes.
The ST no hole 1 2 3 blocks can be purchased and you can drill and tap in any configuration. I can bolt the ST blocks in any way w/o protrusions. I don't see any difference between the Renzetti blocks and the ST blocks. The ST hole/tapped hole configuration is well designed. This in no way takes anything away from either. Besides, I don't think you can buy his blocks. I was just curious as to what, if any advantage, one had over the other. Not everyone has the time or tools to make a good matched set of 1 2 3 blocks. I don't.
The use of 82° flat head socket screws cannot be used.I don't know if the Renzetti blocks can.View attachment 248780
Thanks for the photo, Emilio. That helps a lot. Your ST blocks are beautiful. The Renzetti blocks have a different hole pattern which allows wide ranges of connections, though with smaller fasteners. See post #4 above. Some of the fasteners are special made, not off the shelf. Robin Renzetti might be hired to make a set, but the price would likely be well(!) above the price of the ST blocks. All of which makes the ST blocks more desirable for mere mortals without a high precision shop, the skills to use it, and lots of time to spend making some...
 
I just don't see a need for such multiple block configurations like in the video. Renzetti makes nice things, and I'm sure someone, somewhere has a need for that style of block. I like things I can actually use. And, you have to make special fasteners? The Moore blocks are also very nice and come up on Ebay for $60 or more. I would like Renzetti precision ground tool room stones. I can't make those either. :)
 
I just don't see a need for such multiple block configurations like in the video.
You are no doubt correct there, in my shop either.
I would like Renzetti precision ground tool room stones. I can't make those either.
I have made my first set, and already have several local buddies lined up to come over and grind some. They are incredibly useful, even from just a short time using them. Find someone in your area with a surface grinder, or get one...
 
No need as of yet. Maybe in the future I'll have some India stones surface ground professionally.
 
Special fasteners means making a captive screw by Turning the threads off of a bolt just behind the head.
You drop the screw through the hole, then thread through the threads at the bottom of the hole.
Bolt threads all the way through and becomes captured. Now you can bolt the block to another block.
 
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