90 Degree Machinist Square

I use them all the time.

you don't need to by them new, but in good condition.

IMO are the best for modeling.

Andre.

Finally bought one a while back, I use it a lot.  I have different sizes for various projects.

I have several that I use with my milling machine & lathe.  I also find they are very useful (almost indispensable) in building model buildings & airplanes.

Agree! I use many high-class machinists tools for doing scratch building. And the one I'm using most of all is the ubiquitous Chinese digital caliper. I just bought my second one from Harbor Freight on sale for 20 bucks. In addition to measuring things, I use it to measure one piece and then use the points to scribe that distance on another piece. I have a 12" combination square, and a Browne and Sharpe 6" that I bought used. 

Another source of terrific modeling tools is your family dentist. When one end of a probe or scraper is damaged, they scrap the tool. I just picked up four more from my dentist. He now knows to hold them for me when I have my 6-month cleaning.

I re-grind/sharpen them to make tools that I need. One is a scriber to engrave brick lines. I also use them to scrape excess glue from joints, applying glue precisely, and all kinds of other stuff. And their free. MicroMark sells them, but my dentist gives them to me.

Trainman,

What product number is the caliper?  Every one that I buy over there chews up batteries.  Even if it is turned off.

Very.  Most folks are unable to assemble anyting with a 90 degree angle accurately by eye alone.

And, I actually use a set of 3 small antique carpenter's squares with the nice rosewood handles and brass bits.  Picked them up at any great-uncles estate and use these all the time.

I use 2 of the Pittsburgh (Harbor Freight) 6" digital calipers, on sale for $9.95 most of the time.  They have auto shutoff, and they come with an extra battery.  Such a deal!!

The new one is a Pittsburgh #61585. It's very similar to one that I bought 10 years ago. Like most other Chinese precision tools, I question their metallurgy. The hardness and wearability of their products is questionable. I have some Starrett and Browne and Sharpe stuff that never wears. The American precision tools are infinitely better, but they're so much more expensive that, as a hobbyist only, I can't justify the cost. I would love to have all Starrett equipment. If I was a tool and die maker, I would.

They're so closely identical that I'm sure that they're all made in some gigantic Chinese factory some where. I find that I need to discipline myself to shut them off when not working with them. Nothing bugs me more than to come down in the shop and see the readout is on. I keep a supply of the button batteries. Generally, they last months to the point that I don't remember when I changed them. The new one came with one battery installed and one new one. That means that the caliper itself probably cost 10 bucks. Ridiculous. If they last five or more years at $20 each, that's virtually free.

As to the solid square versus the combination square. The combo square is clearly more versatile since you can separate the blade and use it as a ruler and cutting edge, it gives you a good 45 degree gauge, and you can add a center-finding head which can be useful. I don't have a need for a precision protractor which you can also add. I use some angle tools from General Hardware for angle measurement.

Instead of a solid square, I have two sizes of cast steel angle blocks. I use them all the time to set up walls, machines, and as convenient weights to place on pieces I'm laminating.

Trainhead:

As Andre said I use them all the time for marking, cutting and scoring. I have found the handles on typical squares one buys for woodworking pretty thick plastic sheets I work with. I prop up the plastic on wood or do my marking on the edge of the work bench.

I have just placed an order with MicroMark - 

83261 Thin-Beam Square 1 $17.45 

This should hopefully help things.

Joe

Turtlelinez.  Re the Harbor freight caliper.  Problem is that the foam is the case presses the on button.  Cut away a small square of foam in the case lid, and the battery discharge issue should go away.

Foam case? That's why my batteries last so long... I never put them back in their cases. I suppose I should, but they're being used constantly.

The term machinist square can also be use to describe a combination square. All machinist squares are not combination squares though. A combination square has more than one head that can slide onto a rule. One will provide 90 and 45 degree angles and the other head is used find the center of round stock or circles. Squares with a fixed right angle head are machinist squares. Because the head can't slide it can be ground to an accurate 90 degrees.

Pete

 So what about this thin beam square that Model Structures is talking about.....is that better then a traditional machinist square or do you need both?

Personally, I think one should have both a fixed and an adjustable.  That way, there is no risk of the setting slipping when you want a 90-degree mark.  Over the years, I have also encountered 90-degree fixed squares that were off slightly.

quote:

Turtlelinez.  Re the Harbor freight caliper.  Problem is that the foam is the case presses the on button.  Cut away a small square of foam in the case lid, and the battery discharge issue should go away.

THANKS! I've been removing the battery from mine for storage, which is a pain.

I have also found a 90 degree square that was off a little. Dental picks can be bought at Harbor freight at about 4 for $4.

quote:

I would love to have all Starrett equipment.

I am always on the look out for precision tools at Estate sales and antique shows. I've picked up some nice items that way, such as a vernier micrometer, and a depth micrometer.

Thank you for the idea, but mine will fail hanging from a pegboard.

I have this caliper and it eats the batteries if you do not remove them.

Can someone recommend one from HF that does not?  Part number?

http://www.harborfreight.com/m.../i/m/image_13765.jpg