- Joined
- Feb 7, 2011
- Messages
- 5,039
I would love to get my hands on an 8520. I would be more than happy to design something for it and share it with you.
hint: My birthday is coming up soon.
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Homemade tram tool
- Thread starter Leggman
- Start date
I would love to get my hands on an 8520. I would be more than happy to design something for it and share it with you.
hint: My birthday is coming up soon.
- Joined
- Nov 25, 2015
- Messages
- 8,298
I would love to get my hands on an 8520. I would be more than happy to design something for it and share it with you.
hint: My birthday is coming up soon.
Don't tell anyone it's a surprise.Yesterday was a busy day so I didn't have time for comments. The distinct difference I see in the two videos is one is selling a product and the other is demonstrating the use of a tool. If we do comparisons there's lots of things to compare but I don't see anything in the ET video that indicates compensation has been made for spindle runout, and if spindle runout is a concern, this should be done with an indicator at the spindle.
It becomes confusing when I step into this arena of H-M **Be Perfect** to get explanations that justify otherwise. I realize we are discussing a milling machine with tolerances that vary form machine to machine but pointing out spindle runout while ignoring the 5" long piece of 1018 we pressed into the crossbar/beam/device that holds the indicators escape logic. How true or straight is the piece of 1018 or stock that was used?
With that said, I will default to my position on accuracy. Using one indicator may not be the easiest method but it rules out all the possibilities for errors which are introduced by using multiple indicators. In one way the device demonstrated by tubalcain sets up an issue or question regarding the accuracy of the table, but in his behalf he did mention the importance of the table's flat surface. In the ET video we see the use of a magnet (very small surface) used to calibrate (zero the indicators) the device on one spot of the table, and are we then to assume the flatness of the table where it's indicated for the purpose of tramming is the same. This is a good segue into this video showing a single indicator.
At about the 4+ minute mark in the video he sets up a pair of parallels across the table which is more than an arms reach towards accuracy when comparing the one spot anywhere on the table used to zero two indicators. When using one indicator .0000" is always .0000" given our limited abilities to set to zero, and the same can't be said when using two, because most of us don't have a way to check the indicators against the other. Now if I step a half dozen steps away and pick up a measuring tape the rule still applies. I was taught to use one tape when building a project or product to assure accuracy. The more obstructions we introduce the sloppier the job becomes. I am aware and didn't forget we are making things for ourselves and this is all that's important to some.
I made one of these tools, and it was an eye opener. It made the tramming process fairly easy, but it is sensitive enough that after the adjustment was as perfect as I could get on my little mill, I leaned on the head, and watched the gages move. It makes me wonder just how much heavy cuts affect flatness.
I am so glad I could be of service in starting a s&%t storm on this forum. My only intention was to show a first project on the mill.
It's a good thing I didn't ask for opinions on Donald Trump , or abortion, or immigration.
I DO see the validity of one indicator vs two but I think we are all missing the point. Whether one or two or ten it should all be about what works best for you and makes the job quicker and easier. I personally would rather be making shavings than tramming a mill.
Peace and Love
Dave
It's a good thing I didn't ask for opinions on Donald Trump , or abortion, or immigration.
I DO see the validity of one indicator vs two but I think we are all missing the point. Whether one or two or ten it should all be about what works best for you and makes the job quicker and easier. I personally would rather be making shavings than tramming a mill.
Peace and Love
Dave
I'm not sure how you come to your conclusion about the storm, but from my perspective I look for answers that are more than opinion. Easier isn't always the most accurate but I've come to understand that accuracy isn't a priority and how we get there isn't important for some folks. I definitely wasn't critiquing your project but when I saw your comment I was wondering why you drilled the hole on your drill press and not your mill. I'm a novice at machining, but this doesn't mean I don't understand taking measurements or have the knowledge to use them. I'm here to learn and I prefer instruction based on a standard not an opinion. I know we have been improving on the mouse trap for centuries, and some improvements are better and some not so good.
You can't teach the apprentice to be a good machinist if you promote shortcuts supported by **that's good enough**. I'm aware that a lot of what's presented is opinion and many times I choose to pass. I've watched three of more videos where the promotion of making the spindle square touts how inexpensive it is to make ($30 or less), and the materials list includes two dial indicators from HF. Unless you have the indicators checked against something that's tested and calibrated you could be off by .010" before you start. That's the reality of +/- .005" in manufacturing and it results in a pretty sloppy transmission.
There's a saying that goes; There's enough mystery in the world without creating more. My question to a comment, any comment, isn't saying I think you're wrong, I'm asking you to support it. Now my question to you is; How would you go about making the most accurate spindle square with the tools and equipment you have to work with?
I'm a sheetmetal worker, welder fabricator and when a customer wants a product "exactly" to a specific dimension after I ask what are the tolerances, I tell them they need to find another shop, I don't do perfect. The differences in what I see as accurate or as intended would be something mikey posted that he turned with gravers, and it doesn't have specific dimensions, it's perfect as it is. Another example would be Justin's machinist jack project. I would be more inclined as the instructor to give him 100% on his grade if he wrote a description on how the part ended up .010" short, because I would know he still learned the lesson.
Last edited:
- Joined
- Sep 2, 2013
- Messages
- 54
It is apparent that there is a division of opinions of the validity of this tramming gage. Personally, I made one of these gages and find it quick and accurate. But I would like to point out what ever your preferred method of tramming your mill and you are following this thread, then at the very least it made you think a little deeper into the process and physics of tramming. Which is a good thing.
Sometimes I wonder if thinking is becoming an obsolete skill.
Sent from my iPhone using Tapatalk
Sometimes I wonder if thinking is becoming an obsolete skill.
Sent from my iPhone using Tapatalk
- Joined
- Aug 29, 2016
- Messages
- 838
This. In spades. I'm a root cause of the ****storm. But at least I now have a clearer grasp on the mechanics involved, what is really important, and what is smoke-n-mirrors.
I agree on the division or opposing views and understanding but when we mix words and definitions it can be confusing, especially if the word doesn't fit the definition. I'm a novice, a neophyte to machining, especially the physical application. I think the process is easier to see if we begin with the head trammed in and work backwards by recording the steps. One of the hiccups in the process leans heavy on accuracy, whereas what is probably more appropriate would be to define the calibration process of the two indicators as precise.