It appears you might work for a Defense Contractor which would furnish unnecessary amounts of engineering and quality control processes for
such a simple weldment. Also, money would be no object.
This comment forum is for the birdsâŚ
My sugestion would be: just go back to them and tell them "You are not met my specification"and keep it open.
Do not ask for money back or repair, or anything, just to see how the will manage it.
Iâm not surprised the fixture table let an amateur build with precision, but I am shocked at the basic failures of the professional shops even without one.
Iâd invite the owners of those shops over to demo the fixture table and have a discussion. I think that would be an interesting video.
I admit I donât have experience in the field of welding, but it seems crazy to me that they donât work in decimals or do GD&T. Is it always just assumed there will be post-machining on parts to get tolerances better than 1/16"?
Are complicated (read: proper) drawings not necessary to ensure the parts are built to spec? I mean sure, you could have an informal conversation explaining the drawings and design intent, but if your drawings donât call out the requirement and it comes back out of spec, what are you going to do when they wonât rework it? Youâre just out for the cost of that part because they made it per your drawings and you have no legal recourse. See my comments about the âMax Twistâ callout on the original drawing. Seems pretty shady to do business that way.
For example, what Jason said about the guy who sent back an aluminum square:
Your right I did! I also had a verbal conversation on material also. He was told Steel.
My take⌠Iâm a hobbyist (so probably considered trash around these parts, but Iâve never shy away from offering my opinion), Iâve welded before but I just got my own welder and have some projects in mind that are basically metal frames like you tested the fab shops with.
(Also, interestingly caught this video on TikTok a week or so ago (before it was on YouTube) so Iâve been pondering this for a bitâŚ)
I knew Iâd seen a video of yours where you talked about making things straight and square without needing a welding/fixture table. Because Iâm not ready to get even a basic welding table, let alone a $10k one, I went looking that video and found it. Sure enough, you showed how youâd do it with some angle iron to setup 3 points of contact and then with one of your squares, which was faster and easier. You did all this on your concrete floor and the results were seemingly acceptable and probably better then the frames you had made at the fab shop.
The message I took away from that that video was, even with basic tools, and a little bit of knowledge if you take the time to set things up, you can get good, even great results. And if you want to expedite your work, or level it up a little, here is an inexpensive tool that will help you.
The message I took away from this latest video is, You need a $10k fixture table or all your work is going to be trashâŚ
Maybe thatâs not what was intended but thatâs the gist I gotâŚ
ÂŻ_(ă)_/ÂŻ
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The specification âAll Dimensions +0, -1/16â applies to the 90° angle, therefore all angels would have to be exactly 90 deg ( to a infinite number of decimals, because they need to ad up to 360°).
That means its impossible to produce this part 
Its so funny because I have this argument all the time with my buddy who has his own shop. He says " fixture tables are a waste of time and money " he cant make a square box if his life depended on it.
I couldnât work without my fixture table. Its a laser cut table but still got that thing super flat and its a dreamâŚ
Better than 1/16" tolerances with welding is more than a bit unrealistic for standard âjob shopâ type fabrication. For specialty work, like aerospace, I presume itâs completely different. As a garage welder, the material I would have used to fabricate this, if not otherwise specified, would be hot-rolled low-carbon steel. It has a height/ width tolerance of +/- 30 thou and straightness tolerance of 1/16" per 3 feet. Thatâs the standard Lowes/ Home Depot/ Tractor Supply steel stock, and in-stock at most of your local metal supply houses. Most of this work gets a wire brush to the welds and sent out the door with no other post-processing. For âsanitaryâ welding, such as food-contact stainless, there is often going to be some post-processing. In this case, grinding the welds flat on one face was specified, but grinding welds in general is not the usual thing to do. This would be done with a âflap discâ on an angle grinder in most cases, for tight areas it would be a die grinder. None of this would be considered remotely âprecisionâ work by machinist standards.
If machining was actually needed (for example, surface grind flat and parallel) that would need to be very clearly communicated.
Yup, not necessary for this. Most of my friends who do much more fabrication work in a month than I have done in my lifetime would look at your drawings with a very confused expression, hand it back to you, and tell you they arenât sure what it is that you want. Put welding symbols if you really want to (fillet welds can be presumed here) and fractional measurements and they would understand it well enough. Simple specifications suffice. Think framing carpenters versus finish carpenters. This kind of welding is the framing carpenters. If the wall goes up perfectly plumb, level, and straight, the rain comes in tomorrow, and the next day things are out of whack everywhere by 1/8" nobody cares. For the framing carpenters who built my house, 1/8 tolerances would have been a wonderful day. However, if your finish carpenter is 1/8" off with the miters they are not getting paid (again, except for the crew that built my house). That is more like machining.
There is legal recourse if they screw it up. To pretty much all of the rest of us in this thread Jasonâs drawings were sufficient, in fact more detailed than some of the work I have sent out for simple things, with the exception of the material. For all of the parts, showing that they didnât fit within the specified area on the fixture table and that you can throw the 1/8" shim underneath prove itâs out of spec that is plainly written on the drawings. This is a one-off job, small claims court at the most, with preponderance of the evidence as the legal standard. Nobody is calling in expert witnesses, and the judge isnât going to understand GD&T.
In my own case (a machining story), I had some relatively simple concentric deep holes where the final depth needed to be threaded. A countersunk screw needed to fit. It would cost me more to get long-reach drills and taps than it cost to run to a machinist I know, and he had the tools already. I gave a quick sketch for depths, diameters, and the threading at the bottom. Did I specify the tap drill size? No. Thatâs a fixed quantity anyone can look up (or glance at the tap itself to figure out). Did I specify the threads further than 1/4"-20? Nope. Standard âMachinery Handbookâ tolerances were more than adequate. If I was doing 20,000 of them, sure I would think being more specific would be necessary, with real drawings (or more likely, the CAD/CAM files themselves), but for a one-off job talking with the machinist who was doing the work was sufficient. Did the screw fit? Yes. It was therefore within tolerances.
Some shops tend to specialize in aluminum, so that would be their default material. In this case he verbally specified, and the shop should have written that down, but they didnât. At the least because itâs not only the wrong material, but also way out of spec, it should be re-worked at no cost to the customer.
This was a good test. They got more detailed information than what the average guy coming to a job shop would give them. It is a very simple part to make, with some options to show a little bit of skill and care. Sadly, the shops all failed. I canât say that I could definitively do better in my garage than they did. On most days I have done demonstrably better. On the other days I do a whole lot of grinding.
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I only run the engineering design bit, but yes it is a hefty size operation. Got some really cool machines! About 50 welders on staff, and we make some quite amazing weldments. Mostly we do a lot of complex and tightly toleranced stuff over a range of industries. I had one - picture a large 6 way cross made of tube - with the tubes sized at 40" OD and 6 feet long each, 3/8" wall, with doors on each opening and various other critical features welded in. The tubes had to be straight and then aligned along their axes within .03" and various other features flat to .01", perp to .03" and so on. Things like that can accept (and cause) the overhead, but obviously that precludes smaller things like the frames in this video.
Back to your question - no we donât inspect everything - overkill as you say. Itâs job dependent. I priced out the frames using our most expensive cost centers and adding every kind of additional operation just to see where it landed. If I run it through our component work centers and take a more sensible approach I can make those for $316 each, and I can promise you theyâd be right in tolerance. No way I can make these for $350 a pair though - but thatâs pretty much just an overhead thing. We have hefty cast aerospace quality weld tables, and skim them flat when we need to - we have some very big and very accurate machines. Man I love our shop - and all our shop people are just great to work with too.
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We do a lot of different kinds of work - but yes the size of the operation plus how we approach work puts us outside of the realm of affordability for a lot of small fabricator work. The company was started a long time ago and its origins were a small fab shop. Attention to detail and quality work has grown us to this.
So if youâre going to fab things for a living - use the fixture tables. Do it right. Got to be fast as well.
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I would have actually expected the one-man shop to maybe be able to get the results asked for by geometric construction, but then again, you didnât even get the weld on one side like you asked. Also, Iâm surprised that the big shop barely failed. You did show a few years back that it is possible to make what you asked for without a fixture table but that it would be very difficult (especially with compound errors that would make the precision of the cuts for measurement being about 1/32 for using them as your guide, if I remember the math correctly
Great video truly surprised by the outcome great work from the last guy loved it !
Ngl I love that people are using discourse instead of the youtube comments section. This is so much better <3
I only really have experience with 3d printing smaller stuff and very little 3d design experience using FreeCAD, also some with building mechanical keyboards. This video was a cool ass introduction to the âbiggerâ part of designing and manufacturing stuff.
Go back to the shops and ask for a refund ⌠this is unacceptable from a professional fabrication labs.
@Nici I really like the interaction with everyone on the forum. It much easier to communicate with everyone. The ability to keep a conversation going and search for subjects it great to. Itâs so much better then the comment section on YouTube that typically gets clogged up with spam,
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I am a little surprised the bigger shops were unable to meet your specifications on what really should be a simple project. I think you should at the very least talk with all 3 places and let them know they didnât meet the parameters and give them the chance to fix the work if they would like to do so. If they donât want to fix the work or are unable to meet your criteria then it would be reasonable to ask for a refund. Mistakes happen everyday and people should have the opportunity to correct them whether they do so is on them. Thanks for another outstanding video I always enjoy watching your material.
So there seems to be pushback on the supposition that high-quality tools are not worth it. See SnapOn for reference.
I donât know why anyone would have a grievance with someone who insists on designing and fabricating the finest line of tooling on the market - as an antidote to the crap that Horrible Freight and other purveyors of import throwaway garbage is foisting on us. We were once the supernal model for every other nation when it came to quality engineering and production. Not so anymore. See Detroit automakers for reference.
I love every one of the tools that Fireball Tool is marketing - especially the vise line. Trying to use a cheap vise is exasperating. If I was a full-line fab shop, I would have a subscription to every product that this guy makes - in multiples. Just deliver it. No questions asked. Iâll build on the the shop if necessary.
Thanks Fireball Tool man! I love your content. It is entertaining and informative - answering all the questions I never hadâŚbut shouldâve. Now get out there and come up with a better floor jack! Iâll buy it.
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Iâve not done any welding myself but had visited a shop that did a lot of short runs. They had two CNCs solely for making custom fixtures out of engineered wood or cast recycled plastic. Their plastic fixtures were ground up and re-cast on site. They had a CAD whiz who set up scripts in AutoCAD to design a lot of common fixtures they used. For frames like shown, one fixture was used for both cutting and welding. Their saws, mills, grinders and a few other machines were modified to accept and locate their fixtures accurately. With good fixtures, even made of plywood-like material, even a monkey could get accurate results.
The fixtures were pre-distorted so the cooling welds brought the part to exact dimensions. They could make those same frames probably down to 1-2 thousandths with a robot arm doing the welds, or 5 thousandths with an experienced welder. But they did do precision work with very long parts so the workshop was at a constant temperature, almost like in a cal lab. Details matter where precision matters.
A lot of old USA-made shop tools from the 50s and 60s is still in use in India and Pakistan. They are worn and maintained to various extent, but theyâve lasted this long in constant use.