# A Useful Milling Square



## mikey (Jun 27, 2015)

I wanted to share a tool that I’ve used for going on 15 years now. It is beat up from use but it is eminently useful and very accurate. This one is made for my Sherline mill and Wilton vise but the concept will transfer to any milling vise you have.

Almost all milling projects begin with squaring up rough sawn stock. The fastest and most accurate way to do that, at least in my opinion, is to cut all six sides with a flycutter. If you have squared more than a few pieces with a flycutter then you know that a tooling change is often required to do the ends … unless you have this square!

This little gem is a design by the late George H. Thomas that is unceremoniously allocated a single paragraph in his book,_ The Model Engineer's Workshop Manual_. While it is a simple tool it does what no other square can do – get a work piece vertical when it is wider than the vise jaws (or even if it isn’t). Surprisingly, I have never seen this incredibly useful tool mentioned or pictured anywhere so I thought I would bring it to your attention. 


Basically, it’s a simple T-square with an elongated body and a fixed blade that allows the user to move the blade within or* beyond* the confines of the vise jaws while the body of the square maintains contact with the top of the fixed vise jaw. You flycut four sides as usual then use the square to get one end vertical and fly cut it. Now flip the piece over, setting the freshly cut end flat on the bed of the vise, flycut the other end and you’re done. 





The simple beauty of the design is that nothing interferes with the reference face of the work piece, which is free to fully register against the fixed vise jaw. The width of the work piece is limited only by the dimensions of the square you build.

How accurate is it? That depends on how accurate your reference square is when you make this T-square. I used a Tesa Toolmaker’s solid square, which has a DIN 875 Accuracy Class 00 rating (3 Microns) over its 4” length. As a result, the ends of a work piece typically show zero deviance when measured with a dial caliper and under 0.0001” when measured on a surface plate with a dial test indicator so it’s pretty good.

The basic idea is to take two pieces of precision ground stock and fasten them together with hammered brass rivets fairly tight but still moveable with some effort. You then carefully square the two pieces before silver soldering them together, and then hammer the rivets home. 

This should be enough for most experienced hobby machinists to reproduce this tool but for the newer guys I thought I would include the more detailed description below.


*Materials:*

* Precision ground flat stock – I used Starrett carbon steel stock. You can use tool steel if you prefer but it isn’t necessary.

* Body: The length is not critical. I suggest making your body at least 1-2” longer than your vise is wide. For my Wilton MMV/SP-50 with 2” wide jaws the body is 3” long X* ½” wide X* *3/16” thick*. So far, I haven’t exceeded it’s reach …

*  Blade: The length of the blade should be just shy of the depth of your vise jaws. For my 1.5” high jaws the blade is 1-7/16” long X* ½” wide X* *1/16” thick*.

*  Brass round stock for rivets: 1/16” OD. This is not critical; I used this size to make it easier to hammer it into shape. The rivets are used primarily to hold the body and blade in place until it can be soldered. If I was to make a square for a larger vise I might use a larger brass rod.

*  Silver solder and flux. I used Stay-Brite soft solder and Stay-Clear flux. Stay-Brite melts at 430° so you can use your propane torch for this project. It has a shear strength of 14,000 psi so it’s more than strong enough. At this time, a kit with solder and flux costs about $16.50 from: http://www.riogrande.com/Product/Stay-Brite-Solder-and-Stay-Clean-Flux-Set/503031

*  It is useful to have a piece of brass rod, stick or acid brush to clear excess solder from the joint line. I just used the pointed end of a bamboo chopstick. You’ll also need some Sodium Bicarbonate or your favored pickling solution.


*Procedure:*

1.  Cut your stock to length and clean up the ends with an end mill. Deburr carefully.

2.  Center the blade on the body and align the top of the blade with the top of the body. It helps to put a spacer under the blade to prop it up so the blade lies flat on the body.

3.  Clamp the body and blade lightly and square them with your reference square. Use the most accurate reference square you own as this determines the accuracy of the T-square.

4.  Tighten the clamps firmly and drill two 1/16” through holes for your rivets. The location of these holes is not critical. I actually made a jig to hold the body and blade securely and the jig was held in the drill press vise. Note that these holes need to go straight in so don’t try drilling them with a hand-held drill.

5.  Once the holes are drilled, lightly chamfer/counter-sink the holes on the surfaces that face out. You will expand your rivet heads into these chamfers so don’t make them too much larger than the hole.

6.  We are going to pin the body and blade together but before we do we need to clean the area where these two pieces touch.

I suggest using either Scotchbrite or 400 grit sandpaper to remove any oxidation or surface contaminants, then wash with Dawn or contact cleaner, then wipe it down with lacquer thinner. Once cleaned, do not touch these areas with your fingers.

7.  Cut two pieces of brass rod, about 1/16” longer than the thickness of the body + blade. Using needle-nosed pliers grasp the pin and lightly flare one end by gently tapping the edges with a hammer. I used a ball-peen hammer and anvil for this. Repeat for the second pin.

8.  Insert the pins into their holes and begin tapping them to lock the blade and body together. Use light taps on both sides, working mainly around the edges of the pin; you are trying to fill the chamfers you made earlier. Do not make the pins too tight; you need to be able to move the blade slightly with some effort.

9.  Bring your reference square into contact with the blade and body and move the blade until it is as square as you can get it. Once you are satisfied with the alignment, clamp one end of the body in a vise so you can solder it. I suggest a final wipe down with lacquer thinner at this point.

10.  Note that solder will follow the heat. If the torch is on one side of the joint and the solder is applied to the joint on the other side the solder will flow toward the flame; this is what we want.

Gently heat the joint with your propane torch only from below the body and apply the liquid flux to both sides of the joint. Keep the flame moving under the joint and don’t try to get things hot too fast – you’ll boil the flux right out of the joint.

As you continue to heat the work, the flux will dry and then will suddenly liquefy. As soon as the flux liquefies move the flame to one side of the joint and apply solder to the joint line on the other side, away from the flame; the solder will follow the heat all the way across the joint. As soon as the solder begins to flow remove the torch.

11.  If there is an excess of solder outside the joint you can gently heat the joint and push the excess off with the tapered stick (or an acid brush). If you can’t get all of it off then we’ll do it after the piece cools.

12.  Let the piece cool for a few minutes. While you’re waiting, put several tablespoons of Sodium Bicarbonate in a small bucket or tub and fill it with very hot tap water. Soak the square in this solution for about 10 minutes. Follow this with a hot detergent soak for another 5 minutes (scrub it a few times), then another 5 minute soak in clean hot tap water. This should get most of the acid from the flux off your piece. There are many other ways to pickle a work piece; use what you know.

13.  Once your square is washed and dried you can take a sharp chisel or graver and clean up any excess solder at the edges of the joint. It is important that the joint is completely clear of solder. I use a graver to make a slight undercut at the joint line to be sure the work piece can sit flush to the blade.

14.  Finally, *gently* tap the rivets down until they are well seated. File or mill the excess flush with the surface and you’re done.


It’s tough to beat a tool that helps you work faster and more accurately without calling attention to itself … this is one of those tools.



Mikey


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## Tony Wells (Jun 27, 2015)

Nice tool, and nice tip. It solves a common problem that is often the beginning of many projects.

Thank you for sharing.


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## Micke S (Jun 27, 2015)

Very clever, thanks for sharing !


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## thomas s (Jun 27, 2015)

Thanks for posting great idea.


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## kd4gij (Jun 27, 2015)

Nice job, neat idea


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## mikey (Jun 27, 2015)

Thanks, Guys!


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## Rex Walters (Jun 27, 2015)

Beautiful.

At one time I was a woodworker. Then an instrument maker. Then a metalworker. I think I'm enjoying toolmaking most of all.

George Thomas (my current hero) describes a tool precisely like yours in his book "The Model Engineers Workshop Manual" available from Hemingway Kits in the UK (great outfit and they ship to the US).

George says:


> *SETTING A VERTICAL
> *
> Before leaving the machine-vice there is one other useful item which can be made. When it is desired to set-up a piece of material with one edge vertical in order to bring the top surface square with it one would naturally think of using a square; just try it! The only form of square which I find of any use is shown in (Fig. 3.12). The blade, which is a trifle less in length than the depth of the jaws is planted on to the stock which extends in both directions like a tee-square. In use, the stock rests on the top of the fixed jaw behind the work, even though the work might fill practically the whole width of the vice, and the blade drops down between the jaws and rests against the side of the work. The blade and stock would  be best made fom gauge-plate, say 1/16 in., and 3/32 in. or 1/8 in. for the stock. Rivet lightly with two pieces of 1/16 in. b.m.s. ["Bright Mild Steel" — Rex] When you are satisfied that the assembly is truly square, the joint can be fixed by soft-soldering provided all traces of flux are removed afterwards. Soaking in strong ammonia is the best treatment.



Your photograph is more descriptive than figure 3.12 so I've not reproduced it here! You've silver-soldered yours, and George just soft-soldered his, but if this makes a difference someone isn't using the tool correctly! <laugh>

Thanks for sharing. I really need to make one of these.


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## mikey (Jun 27, 2015)

This *is* GHT's design and the solder I linked to above is considered soft-solder; it works fine for this application. I use this tool at the start of almost every project on the mill and quite often in the midst of a project. Getting something vertical, especially something bigger than your vise, is a useful thing. Make one, Rex, you won't regret it.


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## turnitupper (Jun 27, 2015)

It's late Sunday morning here and I am going to make one of these NOW. If the church group nextdoor complain about the noise I'll tell them I am making a cross. This will be a great improvement over my old cut down square.
John.


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## Rex Walters (Jun 28, 2015)

mikey said:


> the solder I linked to above is considered soft-solder; it works fine for this application.



Yup. My bad. I didn't read the full post — just saw "silver soldered" at the beginning and assumed you were actually using silver (high-temperature) solder.

I definitely plan to make one. I keep re-reading GHT's book and finding more and more little tidbits that I missed the first time. 

I'm new enough to this hobby that I'm still amazed at the level of recursion: tools to build parts of machines to build tools to build... 
-- 
Rex


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## aeroHAWK (Jun 28, 2015)

My vice has removable jaws, therefore I cannot depend on the TOP of the jaw being parallel to the base of the vice. In fact, every time I have checked, it's been out a thou or two. Many may find this fine for their work. I prefer to eliminate the *known* areas where my setup may lead to errors, since I seem to run into enough that I *don't* know about. 

I see your vice also has removable jaws, it may be worthwhile to check the top of the vice jaw too....


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## mikey (Jun 28, 2015)

turnitupper said:


> It's late Sunday morning here and I am going to make one of these NOW. If the church group nextdoor complain about the noise I'll tell them I am making a cross. This will be a great improvement over my old cut down square.
> John.



Yeah, but it will only be a little noise!

Rex, unlike John, it took me well over 5 years to build this one. Now I wonder how I ever got along without it. I think it helps me more than most because I like to fly cut things square; less deflection vs an end mill. Maybe it isn't for everyone but it sure helps me to start off with a truly squared work piece.


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## mikey (Jun 28, 2015)

aeroHAWK said:


> My vice has removable jaws, therefore I cannot depend on the TOP of the jaw being parallel to the base of the vice. In fact, every time I have checked, it's been out a thou or two. Many may find this fine for their work. I prefer to eliminate the *known* areas where my setup may lead to errors, since I seem to run into enough that I *don't* know about.
> 
> I see your vice also has removable jaws, it may be worthwhile to check the top of the vice jaw too....



The top of my jaws are square to the base. I checked before I built this square, Hawk, as I recognized the potential for error. So far, its working out okay.


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## brino (Jun 28, 2015)

mikey,

Thanks for the great detail; pictures, great text descriptions, references, even a parts list and detailed instructions.
I really enjoyed the post!

-brino


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## chips&more (Jun 28, 2015)

aeroHAWK said:


> My vice has removable jaws, therefore I cannot depend on the TOP of the jaw being parallel to the base of the vice. In fact, every time I have checked, it's been out a thou or two. Many may find this fine for their work. I prefer to eliminate the *known* areas where my setup may lead to errors, since I seem to run into enough that I *don't* know about.
> 
> I see your vice also has removable jaws, it may be worthwhile to check the top of the vice jaw too....



That was my thought/concern as well. When I need to square up a project, I just use a small solid square referenced from the base of the vise. If the part is too thin for the solid square, I have a Starrett square (pic below) that I use…Dave.


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## mikey (Jun 28, 2015)

brino said:


> mikey,
> 
> Thanks for the great detail; pictures, great text descriptions, references, even a parts list and detailed instructions.
> I really enjoyed the post!
> ...



Thank you for your kind words, Brino.


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## mikey (Jun 28, 2015)

chips&more said:


> That was my thought/concern as well. When I need to square up a project, I just use a small solid square referenced from the base of the vise. If the part is too thin for the solid square, I have a Starrett square (pic below) that I use…Dave.
> View attachment 106406



I totally agree with your concern. Believe me, I tried everything I could think of to square a piece but if the work is wider than the vise then it presents problems. Since my vise is so small, many things I made are wider. A square on the mill table would be the answer but in most cases the base of the vise gets in the way. Rather than pulling what hair I have left in frustration I opted for this square. Yeah, your fixed jaw needs to be square to the base of the vise and luckily, mine is.

This square may not work for everyone but if your vise allows it then you might consider one. Nothing is more frustrating than trying to work on a piece that is out of square.


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## aeroHAWK (Jun 28, 2015)

Mikey,

I hope you don't feel like I am invalidating your nice tool. If it is working for you... GREAT!  There is a lot of interest... also GREAT! 

I just wanted to make sure others knew there could be a pitfall. But you checked your vise to make sure you didn't run into it. I think it is really nice, and I wish my vise jaw was parallel...  I may look into making it so....


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## FOMOGO (Jun 28, 2015)

Thanks for posting. Definitely going on the list. Mike


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## mikey (Jun 28, 2015)

aeroHAWK said:


> Mikey,
> 
> I hope you don't feel like I am invalidating your nice tool. If it is working for you... GREAT!  There is a lot of interest... also GREAT!
> 
> I just wanted to make sure others knew there could be a pitfall. But you checked your vise to make sure you didn't run into it. I think it is really nice, and I wish my vise jaw was parallel...  I may look into making it so....



No, I didn't feel anything of the kind. You and Dave raised a valid concern, one that I also considered. I should have put a caution in there but its been so long since I made it that it didn't occur to me. Not an excuse but, well, there it is. 

It raises one possible work around. Instead of using a reference square to align the body and blade, could you not put the T-square in place in the vise and then square the blade to the bed of the vise with the reference square? That would allow you to get stuff vertical relative to the bed of the vise, regardless of the accuracy of the top of the fixed jaw. This assumes that the top of the jaw is flat, even if it is sloped a small amount.

Anyway, that's probably what I would do.


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## mikey (Jun 28, 2015)

FOMOGO said:


> Thanks for posting. Definitely going on the list. Mike


 
Yeah, I got a list, too! This is such a simple idea ... makes you wonder how come we never thought it up ourselves, right?


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## Andre (Jun 28, 2015)

Often overlooked on the mill is the ability to square a part using the side of the quill. A great trick to know. When you see no light, your golden.


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## j ferguson (Jul 27, 2015)

Mikey,
That's a slick idea and a tool I can really use.  Could you share a photo of how you affix the Wilton to the Sherline?

Thanks,  john


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## mikey (Jul 27, 2015)

The two photos at the lead of this thread show how it works, John. The body of the tool sits on top of the fixed vise jaw and the work piece is squared up by the blade and then the vise is locked down. Works pretty good and is very quick to use. Give it a try.


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## j ferguson (Jul 28, 2015)

it's the vise. How do you secure the wilton to the Sherline table?


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## mikey (Jul 28, 2015)

Color me stupid, John. I use an aluminum tooling plate on my vise bed. You know, the kind that is supposed to be floated on liquid and then milled very flat. It is full of tapped 10-32 holes and is shimmed to be very level on the bed. I cannot recall who made the plate but it wasn't Sherline or A2Z. 

The vise has two bolt cutouts in the base through which 10-32 SHCS are passed to lock the vise to the bed. The lockdown screws have thick machined washers to spread the load but otherwise, nothing else special about them.

This vise is actually quite a good one. It is not a lockdown-type vise; it has gib screws to limit movement of the movable jaw but it functions quite well.


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## j ferguson (Jul 28, 2015)

Hi Mikey,
I asked because the Wilton looked like something i could use and I was worried about the load that would be put on the Sherline bed by the two bolts on the vise base.  Attaching it to a plate which can be secured to the Sherline with many bolts seems the way to go.
best,

john


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## mikey (Jul 28, 2015)

The T-slots are strong enough as long as you aren't a Gorilla about things. They are surely stronger than a threaded hole in an aluminum tooling plate. The advantage of using the plate is that it is quite flat and can be shimmed to be pretty level across the entire bed. It also allows you to move the vise around in very small increments instead of being stuck with wherever a T-slot happens to be.

This Wilton mlling vise is good for quick work. It is a nice vise, is quite square and clamps very well but it does not have a lock-down design. It relies on gib screws that work well to limit lift but I also use a Wilton precision screwless vise when I need greater precision (all surfaces square to withing 0.0004"). As you know, screwless vises pull the workpiece down as a matter of design but it does so at a price - they are more cumbersome to use. Too bad Kurt doesn't make a really small vise - I would own it.

This is my screwless vise: http://www.wiltontools.com/us/en/p/...-screwless-vise-3-jaw-width-1-3-8-depth/11715

This is the milling vise I use: http://www.wiltontools.com/us/en/p/super-precision-milling-vise-2-jaw-width-1-depth/11708

Both are perfectly sized for a Sherline mill and I can recommend them. Both also have a lifetime warranty - I like that.

The company that made the tooling plate I have is no longer in business. Too bad - it has threaded holes with center-to-center distances of 1/2" covering the entire plate that allows placement of your vise or rotary table with greater precision and had remained flat for many years. It locks to the mill bed with 6 screws into T-nuts and is quite secure.

Sherline and A2Z produce plates. The latter looks more flexible to me - more holes.

Let me know if you have other questions.

Mikey


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## mikey (Jul 29, 2015)

John, I forgot to add that if you go with a tooling plate, be sure you take a lot of time to shim the thing level. The plate is pretty flat but the Sherline bed may not be. In addition, the headstock might not be as square as we would like. I used aluminum foil to shim my plate and used an inch-pound torque wrench to make sure all 6 screws were torqued the same. It has remained dead level for many years as a result.


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