is there anyone who can say sth about Benchmark pro fixture? Pros and cons. Especially what do you think about BB post: you set BB offset from the plane using a thread. I dont’s find this solution too accurate and convenient. Cheers.
I have the Benchmark 1.1. I’ve only had it for a couple months and am still pushing through my first frame using it. The 1.1 is solid, it’s half the price (or less) of the other pro level fixtures on the market and I would say you get what you pay for. It’s easily adjustable, holds stuff where it needs to be, and appears well aligned from my rudimentary verification. It doesn’t have some of the features of the pricier ones that assist in speed and repeatability, but that doesn’t matter for me. The add-on support arms I purchased are kind of flimsy, but because it’s an 8020 style fixture I figured it wouldn’t be too hard to attach my own supports if it ever becomes an issue. It’s also light enough that I mounted it to a sturdy bookshelf. Eventually I’ll figure out how to make it rotate and swing, again it shouldn’t be too hard because it’s 8020 and relatively light.
The 1.1 has the same BB post. I think the picture you posted is only showing part of the assembly. Steve was a responsive and nice guy, but graphic design/presentation is one area he could improve. I noticed the same type of things on the web pages and printed instructions it came with. He’s an engineer not a designer so can’t hold that against him, and it doesn’t hurt the product.
The shaft has mm scale engraved on it with the common BB widths called out with larger lines and numbers. The inner NDS is actually two puck with a spring washer in the middle. Once it’s set it’s solid and not moving anywhere. It might take a minute longer to setup then pucks dedicated to different widths, but you don’t have to buy all the additional pucks for different widths. The 1.1 included BSA and T47 pucks so i’m set for everything I’ll build without any additional costs. It also included a 142TA dummy. That’s a couple hundred $ of accessories I would have had to buy for other fixtures.
I don’t have this fixture but that BB post is how all the Anvil Journeyman frame fixtures were made from v3 on. Works great! There’s a lock nut on the Anvil though, not sure how this one works.
I load the seat tube onto the BB shell and use the “universal tube holder” so that it’s centered, then double-check it’s centered on the BB shell with calipers or a ruler. Once you do that once you can use calipers to measure the amount of offset or stick out the fixtures’ BB cup is from the BB post itself as a quick setup trick. So for example on my fixture, a 68mm shell has 10.5mm of stick out and a 73 has 13mm and a T47x92 has 19.2mm… etc.
I use an adjustable shaft collar for a similar purpose on my homemade fixture. It worked well for me. @hahn_rossman has built many more frames on that fixture and might have changed the BB arrangement.
I was trying to figure out how to get that dimension to be adjustable and had a dream about how to make a fine threaded shaft collar. I woke up that morning and found them as a stock item from McMaster Carr. I love that place.
I’m a Benchmark Pro user for 2-3 years and have been very happy with it. The BB post is quick and easy to change. If you are looking for absolute precision and repeatability you can turn down a spacer to tighten against to provide a lateral stop but I haven’t found the need to do so.
I was fortunate enough to pick mine up directly from Benchmark and go a tour through the shop and a chance to talk with them about their design process. Overall, I’m vey impressed with the tolerances that they hold and their thought process on how they designed the fixture and machining steps to keep the fixture as true as possible.
Also of note, this is the fixture that ENVE bonds all of their frames in.
Thanks for the input. I’m thinking about buying one as an exchange for my home made one as there is one for sale here in eu in.
Another thing that bothers me are ss/cs holders - as I dont see them in any picture - either on website or in the sellers offer. I have made myself them for my fixture And honestly cant imagine working without them.