Tool Tuesday Ep.10: Squareness Comparator 

His voice is a gift.

thats a sad story and it happens way too often.

Good info. I figured the parallel sides had to be less than half a thou tolerance.

Damn, that's a nice gage, not a fixture!

It's mostly cleaning and relubrication which is simple.

End for ending the cylindrical square would have proven any taper related issues or not. Given the apparent surface of the cylinder unlikely there is any issues along the length.

Great point! RU-vid comments can actually be helpful! thanks!

That is all correct.... sort of.... A simple test is to measure the taper (measure the diameter of the T-P cyclinder in several places. If the diameter measures within a tenth or less then it can be said to be "square to the base" within that tolerance. I don't remember if Adam measured the taper (if any) of the T-P cylinder in another video or not. However... even if there is a taper then it appears that it is evenly distributed all around and he can say "this tapered cylinder is square to the base." He can also say "this possibly pyramid shaped tunnel block is also square to its base." He can also say that the opposite end of the tunnel block (the end with all the bumps on it) "does not sit on a plane square to the sides." The superiority of using a "squareness checking gage" like the Taft-Pierce and Ames dial indicator is that it allows you to quantify the squareness with real numbers (thousandths or ten-thousandths over 6 inches etc... whatever) whereas looking at a light gap it can even be difficult to compare two readings. If Adam were to measure the diameter in several places (the 'cylindricity') of the cylinder and finds it to fall within 0.0001" TIR overall then his T-P squareness checking gage when set to zero as he demonstrated and it can be said that those points on the cylinder that he measured are within 0.0001" of being directly over each other and square to the base. A pyramid (or cone) will give results that are further "off" either plus or minus.

May be it is enough just to flip the square upside down and repeat the measurements, without readjusting the indicator. If it show zero again, the square has no taper.

@@Hemml There are several ways in which squareness can be demonstrated. But the point is that none of them are shown in this video. The measuring is interesting, but the title and explanation is misleading.

Yeah, he should change the height on two or three measuring points.

Yes it could be 'conical' but that is easily checked by measuring the diameter near the base and near the point of measurement using a simple micrometer.

@@utidjian or just move the test indicator up the column.

@@millzee60 maybe... but that only works if the column is dead square to the base and you can get the indicator tip exactly over the starting "zero position". One of the strengths of this kind of squareness checker is it can be fairly simple. In a pinch you can even set up a regular surface gage or height gage to be a squareness comparator.

@@utidjian understood. But isn't this a precision measuring instrument with a ground base and the radius on the foot is critical to any measurements. Regarding the tip position, I don't think it matters. It's swept over the work piece and the closest point is established. So long as the tip remains within the arc of the base, it can be moved up and down and side to side on the column and retain its geometry.

All the Federal indicators I’ve ever owned looked just like Adam’s. They have the yellowish hue.

@@wallbawden5511How do you know what he reads and doesn’t read? You really sound like a spoiled little kid who didn’t get his way. Poor baby.

@@wallbawden5511 Interesting, because he actually commented on the Specs from the original handbook. Why so butthurt buddy?

@@wallbawden5511 LOL.... way to dig a deeper hole man! :D Thanks for the laughs though.

Dial test indicators and dial indicators are comparative test equipment. They aren't typically used to measure direct dimensions. That said, you could zero them out on a surface plate and then use something like a gauge block to see if the indicator is accurate.

@@noelhenderson7337 aaahhh makes sense, thanks for the answer.

In the place I used to work we used a micrometer dti setting tool, basically the barrel part of a micrometer on a stand. Bring the DTI up to it and then compare what it says on the DTI to what the micrometer says

i have one hanging from my rearview mirror in my 67 plymouth....chicks dig it

I think most people know Adam is not known for his wealth of knowledge.

@@cokesucks So who benefits from these videos that are perpetually littered with basic errors?

@@tates11 Adam's wallet.

Why? Mark is successful.

If you understand then you know why I said in the video “you always have a tolerance to work within” when inspecting.