Help, please: Advice on how to properly form gravers (without untempering them)

Ramiro

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Jul 1, 2017
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Hi there,

I am making make first steps engraving typographic punches. If you don't know about it is the traditional technique to design letterform for movable types. A letter is cut on the face of a steel punch with files and gravers (mostly used for the letter's counters).



My problem is I am new to working with gravers and I've frequently made them to lose their hardness when forming then with my bench grinder (even using very short touches).

To work on typographic punches I need to form my gravers in a way probably already familiar to you (see image below), taking away a section of the graver's back (in red in my image)



But when using a dry grinder for it, the smallest gravers get cherry-red very easily and if I use a wet stone sharpener (similar to the Tormek) the speed of the wheel is too slow and take ages to erode well the back of the graver.

So can you give me some advice on how to properly prepare my gravers and what tools to use for this task?

Thanks in advance.
 
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mdengraver

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Not the best way, but if you are going to use a dry grinder you need to dip the graver in water frequently to prevent overheating the metal and removing the temper!
 

Tim Wells

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Be patient and take those "ages" to grind what you want on your slow grinder or keep your finger on top of the graver while you're grinding it on a faster grinder and as soon as it gets too hot to hold your finger on, quench it and repeat.

The finer the grit you use to grind, the faster it will heat the graver up. Use a rough one to hog the metal off in short bursts. Then use finer grits to take the rough grind marks out or use your wet grinder for final shaping.
 

John B.

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A heads-up. Be very careful or better yet totally avoid a wet or dry rag anywhere near a bench grinder.
One touch of the rag to the wheel can pull your hand into the spinning wheel and people have lost fingers that way.
Please use a wet paper towel with care. A paper towel will not pull you into the wheel.
Touch the graver to the wheel for just a moment and retract it into the wet paper towel to cool it.
And never wear any gloves when using grinding wheel, especially fabric gloves.
 
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jerrywh

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If you use high speed graver steel you don't need to worry about it. Even if you heat high speed steel to red heat it will not anneal it normally. Read up on annealing high speed steel.
 

Flashmo

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Get a 6" diamond plate off eBay from THK in 100 grit. Mount it on your wet grinder, and run it wet. Delivery is about a week. Cost is under $20. They last years.

Other grits are available as well, but the 100 is great for the initial shape.
 

jerrywh

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John B . Darn good advise. Rags and grinders is bad news. A machinist I know ripped his thumb and tenons out of his arm that way on a lathe.
 

MoldyJim

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Woodcarving does a low speed 1750 rpm grinder for $100 for sharpening chisels etc without burning the temper.
Their CBN wheel for it is supposed to last forever and keep the tool cool while grinding.
A nice sharp alox wheel (white or pink) should do well.
HSS does lose some strength if you overheat it.
Keep your tool cool with frequent dips and let the abrasive cut without forcing it.
 

Ramiro

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Thanks again, guys! During the weekend I tried a couple of your advices and this time I kept my gravers rather cold. I used my bench grinder but this time I wrapped about half of the graver on a ball of kitchen paper and I put an ice cube inside in contact with the graver. Only very short touches with the bigger grit. It really worked well.
 

John B.

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Thanks again, guys! During the weekend I tried a couple of your advices and this time I kept my gravers rather cold. I used my bench grinder but this time I wrapped about half of the graver on a ball of kitchen paper and I put an ice cube inside in contact with the graver. Only very short touches with the bigger grit. It really worked well.

Glad it worked well for you Ramiro.
 

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