Printable View
I bought some used precision tools from Ebay. One item is an angle plate. It’s definitely been used and I was wondering if I could control the surfaces (as to being 90* to each other) with a surface plate. How would I set it up with a dial indicator? Can that be done with a surface plate or is it only possible with a precision square? Is there another way?
Thanks
Not by any means an expert or a machinist, but seems to me you need a surface plate and a precision cylindrical square. You can make your own, though its precision is dependent on how carefully and well you make it. https://www.homemadetools.net/forum/...re-plans-46233Quote:
Originally Posted by GregLaROCHE
HTH!
Bill
By "controlling" Im assuming you want to certify as to square, flatness, and parallel.Thee are several ways to do this but they require some specialized tooling.
You ill need the following a known flat surface your granite plate should work, A precision square known to be square. For this the cheap ones are seldom close enough. A set of feeler gages from .0015 to ,010. you only want the individual leaves as the hole thing is to heavy for a good feel. you will want 2 .001. a set of known parallels or tool makes posts 1"-1.5 tall. A height gage and indicator
Set up the angle plate on the blocks and indicate the flat surface to ensure the surface is true and flat. This is your basic set up for checking the plate.
With the square set the square on the plate with a .001 shim at the bottom snug then try shims at the top till you find the right one the difference between shims is what the square is out.
There are 2 types if cylinder squares a simple one that you set on the plate and see the light between the 2. these normally are dead square in one end the other is lapped to an known angle on the other. Using this end on the plate you rotate the square watching the line of light until it disappears. using this end you can measure the amount out of square.
There is a magnetic version also. This one you stick on the face to be checked wring it to the surface and indicate along the stem this one is self checking by rotating 180* and rechecking it the amount out is the same its a good measurement.
If your height gage has the face on it you can set it up using a square and zeroing the indicator to the square then sweep the face of the angle plate.
A quick check is to lightly clamp the square to the angle plate with a tool makers clamp and indicate the top of the beam.
All of this is dependent on known to be square tools.
This will tell you what you want to know, I will try to be as clear as possible. I hope it makes sense.
All that you need to answer your question is a surface plate, a surface gage, a piece of something FLAT and an indicator.
1. With the angle plate on the surface plate, push the surface gage base against the angle plate. Zero the dial indicator.
2. Clamp the flat stock to the surface you just checked. Let it overlap to the side enough to push the surface gage against the flat stock from the opposite direction.
3. If it returns to zero, you are square to the limit of your indicator and the flatness of your angle plate and flat stock.
If it is not square, that leads to more questions.
I would like to clarify that the surface gauge and the support/stand for the dial indicator are two different things. I bought what I thought was a more accurate stand for my indicator, but when it arrived, there was no place to easily mount an indicator. It had a long adjustable scribe instead. I just Googled surface gauge and the pictures look like what I have. I have bought another base and think it should work and hold the indicator.
What I have is a new granite surface plate, a quality indicator waiting for a stand because I don’t trust the magnetic Chinese one I have. I have several Chinese 123 blocks and when I receive the angle plate there will be some parallels with it.
Now I need to Google cylinder square to figure out what it is.
Thanks for the help.
If it is like the many precision ground angle plates I have in my shops, you would have to hit it with a 5# sledge to screw up the geometry! If it is made with webbing on the back side, it is almost impossible to mess one up. If it is just a piece of home-brew angle plate ground on two surfaces ( I have seen many of those at sales!), I would not trust it.
But follow the about ideas. You will need some rather pricey tools and accessories to verify it's accuracy. And do you REALLY need that precision & accuracy???? If you do not own or have access to those items, better just buy a new certified angle plate and use that thing as a door stop! They are not that expensive.
Thé angle plate doesn’t have any webbing, but it’s only three inches wide and two high. The inside is a rough casting. It’s not new. Definitely not from China.
That’s a pretty small one. If it hasn’t been badly abused or damaged somehow, I would be very surprised if it is out of true. But then again, if you don’t know its history…. Good luck with it. An angle plate is an extremely useful accessory to your mill. ;)
Froggie
I've got a couple similar to that, though one is 4x6, instead of 2x3, IIRC they came from India, so probably not all that much better than the Chinese versions. Plan was & is to learn to scrape and improve the accuracy, or at least learn how not to scrape. In which case the few bucks I spent on them won't really be wasted, as I'll still learn something. I've had the Grade B surface plate, from Grizzly, for about 8 or 10 years now. Haven't even opened the box yet. I should have no trouble filling my retirement with the stuff I've got stacked around here waiting for me... :)Quote:
Originally Posted by GregLaROCHE
Bill
Making angle plates, vee blocks and other tooling is much easier if you have access to a rolling saw. The vertical cut off allows you to rough them in in the saw, saving a lot of mill work.
I have one set of angle plates 1 1/2" X 2" X 2" with a 3/8 thickness, they have 10-32 hole pattern in each face and a small vee cut in one edge. The other set is 3 X 4 X 4 X 3/4" thick and 1/4 - 20 hole patterns. Anything bigger was shop supplied. My favortite is a 5 x 5 x 5 cube this has the 1/4-20 hole pattern on 3 faces . there is a centered 3/4 wide rib in the center to stiffen it.
A "pallet" for in the mill vise is very handy. a simple plate with hole pattern makes holding thin fragile parts a lot easier. Ideally all the tooling should be able to use the same hold down clamps and bolts. these are simple clamp in the vise on parallels and take a dust cut then set up the part.
Buying the cheap tooling saves a lot of work if you have the equipment to "finish" it.
A cheap cylindrical square is a large truck engine piston pin...some are more than 2" dia ,and generally have smooth ground square ends.
You can remove the scribe from the height gauge and make a simple holder to clamp in it that holds a test indicator.
There is literally no chance that a angle plate that small is goofy. It would have had to have been used on a Hydraulic Press or drug behind a tractor or some other stupid abuse.
Just curious are you avoiding extradition by living in France now? or just learning how to speak the language? Seems like a big change from Alaska? :mrgreen: