Heat treatment services?

[Josh Crutchley]

I had a company laser cut a new blade for a Spin I have that was snapped in half. I went with 440c so costs wouldn't get to high because I was already having other things cut out it. I need to get the bevels ground and have it heat treated. I don't have a bevel jig so I'm not sure if I'm going to grind it myself. I know many people do it free hand but that takes practice. I have 2 other small items I need heat treated as well. Does anyone know any alternatives to Peters? With the blade being so small should I do the bevels before or after HT?

[Naperville]

I don't know the answers to these questions. I plan to buy Larrin's book in hopes that it answers these questions. Blade Magazine has Larrin's book, and others on knife making. They may be of help.

If you take a look, Amazon might have an index to his book.

[JRinFL]

This thread from Bladeforums should be of some help. At least until the resident makers here post their recommendations.
https://www.bladeforums.com/threads/bes ... s.1172620/

[TomAiello]

I you have a belt grinder already, buying a jig is a pretty small expense by comparison.

Heat treat is a much more in depth process, and if you're not ready to dive down that rabbit hole (I'm not there yet, personally), you just want to send it off to one of the folks discussed in the BF thread.

[Josh Crutchley]

Heres the blade, just got it in today. Need to get a bevel jig and a file guide. It's 440c.

[Xplorer]

That looks like a fun project. What will you use for grinding the bevel? A belt grinder or a file? Also, have you decided what you're doing with heat treating?

[JonLeBlanc]

I wish I had any recommendation for heat treating for you, but I will say that looks like a fun project, and I hope you get it completed to your liking!

[Josh Crutchley]

That looks like a fun project. What will you use for grinding the bevel? A belt grinder or a file? Also, have you decided what you're doing with heat treating?

I have a belt grinder for the bevel and was going to use the file guide to even out the plunge line. I'm not sure yet about heat treatment. It doesn't need anything fancy just want it to hold an edge.

[Xplorer]

I have a belt grinder for the bevel and was going to use the file guide to even out the plunge line. I'm not sure yet about heat treatment. It doesn't need anything fancy just want it to hold an edge.

The file guide should be very helpful. Are you using a 1x30 or something larger for a belt grinder?

As for heat treating, you have options. Do you prefer to come up with a way to be able to do it yourself?

Doing it yourself for the first time means you either get a lesser quality heat treat by doing it with a torch or a small forge, or you spend about $1500 on a small kiln. I can help you with details either way if you want to try to do it yourself.

Sending the blade out to be heat treated will give you a good quality heat treat and should cost you between $10 and $24 plus shipping. If there's nobody in your area that you want to use for heat treating you could send to Jeff Muntz at Trugrit.com. They're in California so it would mean shipping the blade, but Jeff will provide options, he's willing to do just one blade and his prices are reasonable. They've got all the info on their website.

If you don't mind me asking, I'm also wondering if you plan to pre-grind the blade or grind it entirely after HT?

Best regards,
CK

[Josh Crutchley]

I have a belt grinder for the bevel and was going to use the file guide to even out the plunge line. I'm not sure yet about heat treatment. It doesn't need anything fancy just want it to hold an edge.

The file guide should be very helpful. Are you using a 1x30 or something larger for a belt grinder?

As for heat treating, you have options. Do you prefer to come up with a way to be able to do it yourself?

Doing it yourself for the first time means you either get a lesser quality heat treat by doing it with a torch or a small forge, or you spend about $1500 on a small kiln. I can help you with details either way if you want to try to do it yourself.

Sending the blade out to be heat treated will give you a good quality heat treat and should cost you between $10 and $24 plus shipping. If there's nobody in your area that you want to use for heat treating you could send to Jeff Muntz at Trugrit.com. They're in California so it would mean shipping the blade, but Jeff will provide options, he's willing to do just one blade and his prices are reasonable. They've got all the info on their website.

If you don't mind me asking, I'm also wondering if you plan to pre-grind the blade or grind it entirely after HT?

Best regards,
CK

Just have the little 1x30 but it should work fine for such a small blade. I originally got it for sharpening my kitchen knives. The cheapest route for me would be to just send it out for ht. It's funny you mention trugrit.com that's where I buy all my belts for the 1x30. I have all the different trizact and ceramic belts they sell. The bevels are something I've been asking around about. It seems some people do it after ht and some before. Those that do it before usually leave the apex around .030-.040". People seem to have good luck with full sized blades so this short one shouldn't be a problem grinding them first.

[Xplorer]

Just have the little 1x30 but it should work fine for such a small blade. I originally got it for sharpening my kitchen knives. The cheapest route for me would be to just send it out for ht. It's funny you mention trugrit.com that's where I buy all my belts for the 1x30. I have all the different trizact and ceramic belts they sell. The bevels are something I've been asking around about. It seems some people do it after ht and some before. Those that do it before usually leave the apex around .030-.040". People seem to have good luck with full sized blades so this short one shouldn't be a problem grinding them first.

Thank you for indulging my questions. :) I used a 1x30 for 3 years before I could finally afford the grinder I really wanted. You can definitely do this grind on your 1x30.

There are 2 things that will be challenging with grinding bevels on that machine as it sits in stock form.

1. The platen is a thin "L" shaped piece of steel that will flex. The flexing will lead to a convex bevel and make it harder to get it fully flat. If you want to do a full-flat grind a little convex might not be very noticeable after the top line of the bevel goes past the spine. But, if you want to do a sabre grind the flexing platen will make it more challenging to get a nice straight line at the top of your bevel. Use light pressure (especially as you get close to finished) in order to keep your grinds flat. Although this might sound counter-intuitive, as you get close to finishing the grind "leaning" slightly more pressure toward the cutting edge will actually help straighten the line at the top of your bevel.

Here's the stock platen next to the custom one I made from heat treated 52100 after I realized the flexing was making things difficult.

It was much easier to grind after I eliminated the flex. You don't have to do something like this but I wanted you to see where the issue exists. Seeing the difference between what the platen looks like and what it "should" look like illustrates the problem. So, in addition to using light pressure you might want to wedge a piece of wood between the back of the platen and the grinder frame to make it rigid.

2. The grinder runs way too fast. Heat is generated very fast because of the speed of that machine. Here again, light pressure is your friend. For doing the pre-grind it's no big deal if you get the blade hot. However, once it's been heat treated and tempered that's a totally different story. Switching out belts as soon as they stop cutting efficiently will help a lot. Once a belt gets worn it burnishes more than cuts and that generates heat quickly. Keep a bucket of water next to you and dip the blade as soon as you feel it getting warm. Use bare hands so you can feel the heat immediately. If you can rig up something to spray water on the blade that would be even better than dipping in a bucket.

Here you can see the misting unit I built zip-tied :o to my old 1x30 and then properly mounted to my new grinder.



If you want to consider water cooling, you can get creative and come up with a sprayer yourself or there are spray units available from lots of tool companies. I know it's an extra step that seems a little over-the-top for just one blade, but I'm suggesting it because it really does make a difference in the final outcome of your edge and worth the extra effort.

I'm glad to hear you found Tru-Grit for your belts. I don't know of any source with a better selection of 1x30s. If you haven't tried the scotch-bright belts you might want to consider them for doing a nice even finish on your blade.

As for pre-grind or not...you can go either way with this blade. I heat treat the majority of my blades prior to grinding and do the entire grind on the hardened steel. But, this is a choice I make because of preferences I have about how I want my plate quench to go and I've got a variable speed grinder with a water mist system that I built to keep my grinds cool. So, your grinder will handle grinding on hard steel no problem, but the heat will be an issue for you post heat treat. If you pre-grind you are correct to leave .030-.040" at the edge, otherwise you risk some warping creating an issue you can't grind away. Since the blade is 440C I (personally) would heat treat it with no pre-grind because I would be plate quenching that steel and I want the edge to quench as fast as possible. If there's a pre-grind the edge doesn't make contact with the quench plates during quenching and then the edge cools more slowly than the spine. In all reality it shouldn't matter with most steels, but I'm admittedly a little nuts about all the little details.

When you're ready to grind your bevels, mark your spine and your edge with a marker (I use Dykem metal dye but a marker will work, a paint pen is even better). Then, scribe lines on both the edge and the spine. Preferably you'll want to scribe 2 lines down the center (with a .040" gap between them for a pre-grind or a .015" gap for a final grind). You'll then use those lines as your guides for how far to grind. The lines on the spine (and the lines on the edge of course) will be helpful for seeing if you're grind is centered properly at the tip as well. If you don't have an adjustable scribe you can use calipers (but you're going to round the edges of the caliper jaws a little) or you can use the correct sized drill bits laying on a flat surface and drag the tip along your blade.

Tip...Scribe lines will be easier to see if you first lay the blade flat on your grinder table and grind around the profile so you have lines cutting across the spine and edge before you scribe lines length-wise.

Another thing that will help you grind clean lines is to make sure the blade stock is FLAT. You can put sandpaper on a sheet of glass if you don't have a surfacing stone. Sand it until you can see it's truly flat. Alternate sanding direction if you do more than 1 grit. Any little bends, warps or surface inconsistencies will just make it harder to get clean looking grind lines. You can and should also sand the sides after grinding bevels to help clean things up as well.

Since your blade is so small it's going to be relatively easy to grind, just remember that you can't put back anything you remove so take your time and it should go very well. Even though it's a small blade, experience has taught me that you'd be wise to practice that grind on a sacrificial piece of metal or even wood first just to get a feel for the motions and let any oops :o happen on the practice piece.

Good luck with your project. If you have questions along the way let me know. :)

Chad

[Josh Crutchley]

Good luck with your project. If you have questions along the way let me know. :)

Chad

WOW! Thank you for all the tips. That upgrade for the 1x30 is definitely something I'll do. I asked a while back about a mist setup. I have a few pumps and have plenty of agriculture stores nearby I'm sure I can find a nozzle. The idea about better plate quenching without bevels makes sense.

[Xplorer]

I have a few pumps and have plenty of agriculture stores nearby I'm sure I can find a nozzle.

I use an aluminum canister for automotive fuel injection cleaning that I fill with water and then pressurize it with 100psi airflow. This way I have no pumps and the system is simple, but I have to re-fill the canister after about 30 minutes of constant flow. If you have a pressure pump already all you need is a a tub to store and catch the water in, a nozzle and a couple stages of filters on the supply hose to keep the nozzle from getting clogged. The smaller the droplets you can get out of the nozzle the better.
Here's a picture from a few years ago that shows the canister and also shows how I had to use a trash bag to route the over-spray water into a bucket.


A 5 gallon bucket is easy to modify into your water container. If you don't have one already, you can get a good free "tub" at most car dealerships. All car dealerships have a car wash area. Many, if not most of them use 5 gallon HDPE cubes of soap and tire shine and de-greaser etc..(I know because I used to sell the stuff) and when a cube is empty it's trash to them. Ask the service manager if you can take one or more of their empty soap cubes and he'll most likely be glad to save the space in their trash dumpster. The HDPE cubes have a nice threaded lid with a small hole for a hose to run through. Or, cut the top off and they make a good shop trash can too. I use them in multiple places in my shop, but you might want one for your water system.
I don't have a good picture of one without the top removed anymore. Here's one I wrapped tape around and added some aluminum sheet metal at the top to catch the water and grinding dust.


One word of caution..while it may be better for the blades to grind wet..it makes a mess no matter what :rolleyes: .