Continuing the discussion from Fixture table build…the hard way:
Okay, whatever I did, it didn’t carry over. Anyway, I was trying to start a new thread, and refer to Wisco’s thread while not stepping all over his, but nobody ever called me tech savvy. I finally got around to starting my own table, 36” x 60”, but I was going to document and photograph as I went, and then just post it all up when I got done. I got one row shy of halfway done and figured I would swing the template 90* and check out how the holes lined up- THEY DONT!
I am beyond mad right now; and here’s why:
I’ve followed Wisco’s entire build, and probably read it twice; apparently I missed the part about the template not lining up when he turned his 90*, I just read his thread a third time, and I caught the part where he mentioned, as did someone else, that there are potential issues with the templates being off when turned. Had I paid better attention, as well as remembering that fact, I might have been able to correct, or perhaps prevented the problem from happening.
I’m retired, so I have all the time I need, and have been working at a snail’s pace to make sure everything works as expected; I literally check the clearance of the cutter every hole; yes, there actually is a slight gap between the cutter and the hardened drill bushings in the template! The only thing I DIDNT check was the template itself; shame on me, I guess, for trusting that the $259 template was accurate from the beginning…. Yeah, I’m looking at you, Jason; one guy has an issue, hmmm. A SECOND guy has the SAME problem; double hmmm. THIRD guy has the SAME problem, ok, WTF man?
And here is where it gets even stranger; once I realized that the template didn’t work when turned 90*, I started thinking “oh crap, I have a LOT of fixtures that aren’t going to work”, it occurred to me that the most expensive one was the 3 axis XL square; another couple hundred bucks out the window! So I screwed the pins into the bottom, and IT FIT! Then I proceeded to try the square in 6 or 8 different places, and rotated it as well; IT STILL FIT! It doesn’t make sense, but it actually worked. It also doesn’t change the fact that the template(s) was/are not made correctly, and if I continue using the template as it was intended, and demonstrated, how far off will the hole pattern be over 60”?
I guess what I’m saying is that even though the 3 axis square fits, and smaller, shorter fence blocks fit, it doesn’t matter if the overall hole pattern isn’t equal between the x and the y axis; isn’t THAT the purpose of a fixture table in the first place? Because if inaccurate spacing is what I wanted, I would have spent a few more bucks and just took the plate out to the range and used the 50 cal on it; seriously. Not quite sure how I should proceed at this point….
I believe it was Erle who began using a dial indicator with each new placement of the template but he hasn’t updated his thread.
I haven’t performed dimensional verification of the grid or checked the template across a greater selection of test holes for fitment but of each time I have tried, the distance is greater along the length every time.
However, I use the fixtures a lot. Some holes will be snug and it’s more of a vertical alignment issue/user input because they will come out easier than they went in. There have been spots where I’ve encouraged them with a dead blow but will drop on their own after the first tap.
The more I use the table and the holes lap-in, the blocks and clamps drop in with ease. So far I haven’t encountered a spot where a fence block won’t fit X, Y or 45*
When does the video drop for the .50 cal range/fixture table? 
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Now you’ve really got my curiosity peaked; because in my case, the hole pattern gets more “crowded” along the length, which is the opposite of what you have. I will assume that because you drilled the skirt pieces first, you drilled them length wise, and then while they were still attached, you flipped the template 90* and started working your way down the length of the plate. Did you then use the first holes in the skirt as an initial point to locate the template, and just skip a hole? Or did you start fresh using the short edge and work independently of the holes already drilled for the skirt portion and just not cut them off until you were completely done?
Let me make/edit some photos that illustrate better than word salad.
Yes, I need to apologize for the salad, but at least I read it and tried to condense it the best I could, because it started out like a word buffet….
All holes were indicated from the edge and/or corner utilizing the guide pins for the template. The grid is set to the default 2” from the edge. To clear confusion, the skirts were drilled prior to cutting for the mag base. The template was set from their lower edge for 2” pattern.
Here’s a bunch of random samples from today. Last pin is 2-3-5th hole before no-go. Roughly 1/32” of max variation by end of template. It becomes increasingly noticeable to the eye lookin down the bore of the templates.
This illustrates the blocks fitting where the template won’t
Length axis variations
Grid dimensions
Skirt blocks
This is the orientation in how this table was drilled. Pins drop with the most satisfying sound across all holes. Also long side skirt blocks.
Blocks where template disagrees again on 24x36 table
Random samples and pin locations
Same test on the unfinished 30x60. The grid falls short by a 64th. The machinist rule would catch the end of the yard stick.
Direction of drilling
90* typically only 2nd or 3rd pin would drop in either direction of “zero” for testing. But you can see the fence blocks all drop.
I understand your frustration and I hope it works out for you. Hope this helps restore your excitement in the project as well as for others who want to go this route. Attention to detail is a must and my accuracy/attention falls somewhere in the middle for what’s achievable with a job like this. Certainly there’s some folks who could really dial in the process with instrumentation and more patience.
In the end it was worth it as I can achieve an incredibly higher level of quality than working on wooden benches or wavy concrete floors. I’ve used the tables for not-welding jobs etc and it’s just too cool to set up some blocks, shims etc and accomplish a task.
Forgive my comprehensive abilities, at least for the moment (no coffee yet). If I understand correctly, the holes in red were NOT used to locate and/or hold the template for drilling the holes in yellow, correct? Yes, sometimes my blueprint needs to be made in crayon, just to clarify.
Correct.
There’s a 1/2” error along the cut/parting line because the skirts butt against the bottom of the table surface to have an effective 6” surface and 2” grid and hole C/L to edge.
For my table dimensions, I was always able to indicate the template from the edge of both X & Y with the guide pins to begin the 2” pattern and continue production with the tacking bolts. No measuring or conversions etc needed or floating of the template in space.
Thank you for clarifying that for me. Because if you did in fact use the holes in the skirt to locate the holes in the main table area, the fact that the fixture plate is inaccurate would have likely caused a whole new level of distortion to the overall hole pattern.
I was reading through some of the other threads, and at least I know why and how the error occurs; but it doesn’t change the fact that not only do they know they have an accuracy problem, they have yet to fix it. At the very least, they could have created a category dedicated to dealing with THEIR OWN product’s shortcomings, and the workaround. At best, issue a product recall, but we all know that ain’t happening.
You are definitely highly skilled and it shows, you do some amazing work, keep it up! As far as my table goes, I’m not giving up on it at all, I’m just super pissed off that 48% of the work already done is not as accurate as it should be, because (more than likely) everyone has paid good money for something that should have never made it past Q.C.. But at least someone figured out what the issues were, so I’m gonna go with Erle’s method for the rest of the drilling, as it appears to be the correct solution; I thought about doing the same thing before I knew about his thread, but wasn’t sure if it would possibly magnify the accuracy issues.
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Gentlemen: I have a question, or perhaps an observation. Is the spacing of the 14 holes drilled along the template ever non-functional? Follow up: If a full square pattern of 196 (14 x 14) holes is drilled into the table does the template match every row across but fail to match the 14 rows at 90*(degrees)? Consider that after locating the template against the edge of the plate and drilling the first row of 14 holes the next row of holes will shift 2 ways: First, the template will not locate exactly to the two holes it is pinned into and second, each hole in the second row of 14 won’t be exactly centered to the bushing (consider the drill or annular cutter has a bit of clearance inside the bushing). These sources of deviation may be managed well or poorly, or they can be ignored at your risk. Consider if you pull the template back towards the originally indexed edge of the plate AND make each hole as close as possible to the side of the bushing closest to the edge. A “stack” of 14 rows of holes will not be square. It will be “short” with each hole in each column getting a little closer to the index edge than it should be by design. The opposite is also possible. Or if you’re not pulling or pushing the template or the cutter the deviations may kind of randomize, with deviations cancelling each other rather than accumulating.
It’s also worth considering whether the locking pins are two ball or three ball. (They look like three based on the pictures which is good) A two ball pin would pull down and lock but would have different “floats” along or across the line of the balls. A three ball pin won’t have this opportunity to float in an eliptical pattern but may still float a bit randomly. And a tiny chip or burr may affect exactly how a pin centers in a hole or how a hole centers on the pin. (Care in keeping the theater clean is important!!)
Anybody still awake?
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Yup, you didn’t put me to sleep! Thanks for this explanation and illustration of the potential issues Mike. I knew intuitively that there would be the potential for the holes to have some dimensional creep, but do not have the ability to see/understand/explain that you have. I think your explanation is very helpful.
–Larry
To answer your question, yes, after completing a grid of 196 holes, the template is non-functional when turned 90 from the original direction it was used to drill the holes. Now this is what makes this issue so frustrating- watch the video that Jason made showing exactly how to use the template, listen to his comments, and then DO THE EXACT SAME THING; you will have the same problem as the rest of us. And if you paid attention, even though he claimed that the template could be used as your first fixture, he DID NOT flip it 90* and put the tacking bolts back in; if he did, you would have seen firsthand before expending any effort or money, that there is a problem.
As far as the holes shifting in 2 directions, yes, that is absolutely possible; otherwise we wouldn’t be having this conversation. After reading every post and thread I could find regarding this issue, the problem becomes VERY clear; #1, the tacking bolts are undersized, and #2, they should never have been used to locate the template. Think about it for a second, it is absolutely possible to produce a template with .0005” accuracy; others have measured and determined that their particular template is within .001”, which is not ideal, but when you add another .001”? clearance between the bushings and the annular cutter, plus the .004” undersized tacking bolts, this quickly exacerbates the problem.
If I bought this thing from Scamazon, or Temu, then I’d expect to have this kind of problem, but for an American company, at this price point, I expect better; we ALL should. At the very least, explain how this product can possibly produce inaccurate results as a result of what you are given to work with.
I believe it was TheOther Joe who initially figured out what the problem was, and he acquired some round bar with a tolerance of +/- .002 to fix the problem going forward on his project. I went a step further and got tight tolerance precision ground bar with a tolerance of -.0004; WOW, what a difference between that and what you are given, AND you are given the impression that you can make anything even REMOTELY accurate. All the aggravation caused simply because Fireball provided the WRONG part for the task at hand. SIX DOLLARS worth of precision ground bar, and the problem becomes so small that any errors are basically gone!
As far as the number of balls is concerned, I would say three is better, but when you have a pin that fits about as tight as a hot dog in a hallway, it doesn’t really matter much. And yes, one can argue all day long that the end result is user dependent, and that is true, HOWEVER, six more dollars for tighter tolerance pins that ACTUALLY WORK AS INTENDED? I think you would be having an argument in a mirror, if that’s the hill you choose to die on. I would gladly pay another 6 bucks and NOT have issues. I’m also not advocating to make an idiot proof tool; someone else would be along shortly with a new, improved idiot.
Hopefully, I answered all your questions, and you’re still awake after the novel I just wrote 
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I so sincerely appreciate your efforts to bring me up to speed. It’s so hard to really positively understand when I can’t lay hands on the tools and materials involved in the project.
I spent decades trying to bridge the divide between the “Well it lines up perfectly on paper (or in CAD)” from the designers and the “Well the holes don’t line up” experienced with the actual parts. Spotting the errors and assumptions that lining things up with two pins looks good (in theory) but often isn’t even “good enough” in practice. Consider: A hole in the plate has an axis. The corresponding hole in the fixture also has an axis. And the ball-lock pin that goes through both of them has a third axis. Three different axes each defined by a different specific diameter of a specific part.
Design intent is pretty obvious; all three axes are intended to fall on one single line- That’s what the design says. Reality says there’s a bit of clearance between the pin and the hole in the plate; the pin might not be at the center of the hole AND it might be leaning in some specific direction. Add the template on top- is the drill bushing aligned by the pin passing through it or by the template lying on the plate? Hey, nothing’s perfect. And these little deviations and the tendency to say “Good enough” every time there’s a chance for either radial or angular misalignment. In our minds everything is perfect. In reality everything isn’t. Then there’s the clearance between the cutter and the bushing. The angular alignment is pretty much determined by the mag drill on the plate (but how flat is your plate? And is there a chip or burr it’s sitting on?) but any clearance (an absolute necessity for actual machining but often ignored in design) allows the three axes, EVEN IF PARALLEL to misalign) . On paper or in CAD a 0.750 pin fits a 0.750 hole every time. “Of course they’ll ream those holes 0.002 oversize. Of course they’ll turn and polish those pins to 0.002 undersize”. To me these are “Famous last words”.
But when things don’t align perfectly it’s the guy on the floor that makes it work. Ream the holes a bit, knurl the pins, “Tap” it with a hammer. How many designers or CAD jockeys even understand what goes into making a design, with design faults, actually work in the reality of assembly, with added part faults? I’m one of the guys that tried to get those floor fixes pulled back into the designer’s realm for next time.
So, after you drill the first row of 14 holes do you measure the thickness of the webs between each of the holes and its neighbors? Measure close, we’re looking for differences of thousandths or even ten thousandths. Then reset the template and drill the next row. Measure the webs between the first and second rows. Compare those measurements to the measurements within a single row. Toss those measurements into a Excel spreadsheet and plot them. It’s predictable that the measurements of the webs between the holes within a row will be much closer together than the measurements from row to row. (The actual values, and the average of each of the two groups, will depend on the actual size of the holes produced, which may not be the same as the nominal size of whatever cutter was chosen)
ZZZZZZZZZZZZZZZZ
No snooze alarm needed Mike! Your efforts to explain and provoke thought are valuable both for the folks trying to get the most from a drilling template and those who want to be able to achieve better precision in building things. After reading and reflecting on your explanation my conclusion is once again, there is no such thing as a “free lunch”.
–Larry
Thanks Larry, Without laying hands on I’m just about down to random tidbits. Consider: The clearance required between the cutter and the bushing… Has to be big enough for the cutter to spin. But there’s also the matter of the exact axis of the bushing vs the axis of the cutter. Yeah theoretically they are the same but is the cutter aligned by passing through the bushing? Or is it aligned by being in the mag drill, magnatized down to the plate, that also supports the template? Lots of fits in there that might not exactly fit / might bind. The practical answer? Clearance. Make some room between the bushing’s version of vertical and the cutter’s version of vertical.
On alignment pin size: The first alignment of template to plate is by two small pins through the template then bumped against an edge of the plate. Drill a row of holes. Now forget about the edge. It could be un-straight in any number of ways (The plate could even be circular) but you’ve got a new starting point; the row of holes. But what size pins do you use to locate the template to this row? The bushings are a bit bigger than the cutter and the new holes are really close to the size of the cutter… The bushing will float around a pin that is “tight” in the hole. And a pin that is tight in the bushing won’t fit into the hole…
If only we had pins that would fit in first, then expand, to two different diameters… (They exist for hundreds of dollars). We kind of try with the ball-lock pins- tightening them pushes the balls out to clamp the pin in the hole (and at the same time pull the template down to the plate) but there is actually a LOT of UNCERTAINTY as to what is aligning what. Is there a chip under the template? What about the roughness inside the drilled hole? A burr under one of the balls will dis-orient the ball-lock pin as it is tightened as will a chip under the head of the ball-lock pin.
Another possibility would be pins with two different fixed diameters; One to fit the bushings and a slightly smaller (never larger) diameter to fit the drilled holes. Fitting the bushings is relatively easy; they are precision ground. But fitting the holes? What size did you make the holes? What cutter did you use? What size hole does it actually produce? Does it wear as you drill a couple of hundred holes? Is it reasonable to expect Fireball to provide a pair of pins that meet the customer’s choice of cutter (and skill level to make 200 holes all the same size)?
So, some recommendations: Fireball should pick the cutter. Make it part of the kit. Maybe offer a discount for customers who are sure they can make correctly sized holes and don’t think they need it. If at all possible, the actual hole size produced should be as close as possible to the bushing size. Fireball instructions should point out the myriad of ways to do it wrong and ways to check if one is on track or deviating. Catch deviations/mistakes after each row, not after all the holes are drilled.
To foster customers’ production of better hole patterns it might be worthwhile for Fireball to produce a special pin, just for the template kit, that actually expands into both the bushing and the customer drilled holes. If somebody doesn’t make it, I can think of a couple of possible pin designs… But this would be complicated by trying to accommodate the customer’s choice of plate thickness (and potential hole diameter differences if they use their own cutter!).
Another consideration is the possibility of LOCATING the template using two pins that only expand, without vertical clamping, while providing CLAMPING by clamps (near the edges) or bolts and nuts, through extra holes, out in the middle.
Hey Jason, any interest in collaborating?
The drill template is designed for small surfaces that could use a hole pattern. This is a DIY tool, human errors are common. With so many variables that can be introduced by the user the outcome is going to vary between users. Also If you’re using off the shelf plate steel I suggest lowing your expectations to a reasonable tolerance. There’s a reason professional tables and fixtures are priced the way they are. It requires special equipment to achieve good table results and accuracy.
Fireball has options that can provide a high accuracy tolerance if that’s important to the customer. Such as Pro Kit Plates, or cast machined platens tables accurate to +/- .003 flatness and +/- .002 hole centers. If you are expecting this precision from a 300 dollar DIY drill template than you’ll probably be disappointed.
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Mike-
Last paragraph is spot on, and can easily be understood by an ADD sufferer! That said, I don’t think anyone here is expecting perfection, myself included, but as discussed, alignment pins seem to be the key to success, while not requiring one to use 5,000 dollars in metrology equipment to achieve the INTENDED result.
The reason I capitalized the word INTENDED, there, I did it again; is because when you watch most, or all of Jason’s videos about the fixture tables, and their purpose, is to produce repeatable results. I suppose that no matter how far off the hole pattern is, any given table will be capable of producing repeatable results, though the results will directly represent how far off the pattern is, and be repeatable on only that particular table, and only if the fixture blocks are either not moved, or put back in the exact same holes.
HOWEVER, anyone who made it past 3rd grade can understand the concept of repeatability, as well as Jason’s intent when he designed the dragon wagon and all of its variants. I can’t remember what the exact video, but it showed that he could design something on the computer, and in a short amount of time, you are able to place the necessary fixtures on the table, and start cranking out whatever it was that you’re making. The important part is because the table, and thus, the hole pattern is accurate and consistent, you don’t need to measure anything in order to place your initial fixtures, likely only when you need to double check before you start welding. If I’m remembering correctly, Jason said the same thing, not verbatim, but close, like “the hole spacing is on a 2” grid, so all you have to do is count the holes, and place the fixtures accordingly”.
I’m not saying that you shouldn’t measure anything before welding, I’m referring to one of the GREAT features of the table design, and, when you have a CONSISTENT hole pattern, you can, based on the size of your table, and the size of your project, start anywhere on the table (within reason, obviously), and have a workable setup quite quickly and easily. But if the hole pattern is inconsistent, you may as well not have holes at all, and just start clamping stuff down at random.
I’m sure some of the people who read this thread are thinking I’m just trying to bash Jason; and they would be completely wrong. Most of Fireball’s lineup consists of products that aid in accuracy, as they should, overall, they make some great stuff, there’s no argument there. My issue, is that they offer a product that, due to the lack of an accurate (as realistically possible) positioning feature; E.G. LOCATING PINS! Like I said before, a WHOLE lot of aggravation could have been avoided, for SIX DOLLARS worth of steel. The tacking bolts are necessary, but by their own design, they cannot serve dual purposes, they are to hold something down; Fireball even offers specific “location pins”, so why are they not included with the template? I would think that would be an even bigger selling point, obviously the overall price would go up a few bucks, but there’s nothing wrong with that. Contrary to a previous comment, I, and probably everyone else, is not looking for a “free lunch”, just a product that can and does provide the best way possible to achieve your own table. No more, no less.