Where can I get these hardened?

[Mark Gibney]

These are a pair of thrust bearings for a Davis & Wells 14" bandsaw that a machinist turned, and I need to get them hardened.

417267

One place here in LA I called has a $150 minimum, and depending on what kind of steel they are, the cost could be $250 and up.
Of course I'd like to pay less, and I don't mind mailing them somewhere to have them done.

I've watched a few youtube videos on the DIY process, but I'm not sure I want to get into that if I can find a viable option.

Any information appreciated!
Mark

[Doug Garson]

I assume you did the obvious, ask your machinist if he could do it or recommend someone?

[Bill Dufour]

CCA glue or braze a carbide disk onto them. Not all steels can be hardened. Is there enough carbon?
Bill D.

[Derek Cohen]

Will glue remain stuck once the friction of the blade running past creates heat?

On a related note, I had an idea to glue ceramic disks to the existing thrust bearings on my Hammer N4400 bandsaw. The question is similar - can these be glued successfully and not transmit heat?

I imagine that a ceramic guide block will have less friction than carbide or hardened steel.

Regards from Perth

Derek

[Lisa Starr]

Your first step is to find out what grade of Steel they are a made from. Do you know how hard you need them to be? If your machinist didn't know you wanted to harden them, he may well have used C1018 or C12L14 (Leadloy) both of which do not have enough carbon to be able to Heat Treat.

[Jerry Bruette]

Get some Kasenit or Cherry Red from Grainger, McMaster-Carr, or MSC and case harden them. It won't matter what grade of steel they're made from and you won't have to worry about tempering them after hardening.

[David Buchhauser]

These are a pair of thrust bearings for a Davis & Wells 14" bandsaw that a machinist turned, and I need to get them hardened.

417267

One place here in LA I called has a $150 minimum, and depending on what kind of steel they are, the cost could be $250 and up.
Of course I'd like to pay less, and I don't mind mailing them somewhere to have them done.

I've watched a few youtube videos on the DIY process, but I'm not sure I want to get into that if I can find a viable option.

Any information appreciated!
Mark

Hi Mark,
Do you know what alloy they are machined from? I machine some of my parts from 4140 alloy steel and send them to Phoenix Heat Treat for heat treating. I request a process that results in a hardness of 60-65 Rockwell C scale with a minimum case depth hardness of 0.030" and a core hardness of around 50 Rc. The last batch I sent was 40 pieces and the total cost was around $140. As was mentioned previously, you can use Kasenit to do a case hardening even if they are only mild steel (1018 or equivalent). If they happen to be machined from O1 tool steel, then you can heat with a torch and oil quench to harden them.
David

[Mark e Kessler]

Hardly any heat from that application would pass through the ceramic and affect the glue line. There are high temp epoxies specific to ceramics available rated up to around 2200c...

http://www.cotronics.com/vo/cotr/index.htm


Will glue remain stuck once the friction of the blade running past creates heat?

On a related note, I had an idea to glue ceramic disks to the existing thrust bearings on my Hammer N4400 bandsaw. The question is similar - can these be glued successfully and not transmit heat?

I imagine that a ceramic guide block will have less friction than carbide or hardened steel.

Regards from Perth

Derek

[Bill Dufour]

Brazing them in place will certainly hold up to any heat.
Bill D.

[Mark Gibney]

The machinist got back to me and tells me these bearings are milled from 4340 steel.

Some great ideas on braising / epoxying on a carbide or ceramic disc, and using Kasenit / Cherry Red to harden. I'll call Phoenix Heat Treat and see what they can do first.

Thank you all.

[Brice Rogers]

I'm a shade-tree or back yard heat-treater. I have heat treated a bunch of things that needed to get hard but which weren't overly critical (unlike airplane or car parts). The heat treat companies are employing a super precise regimen where it is critical. But for what I do, that is overkill.

I heat to the "Curie point" (google it - - magnet doesn't stick) - typically bright red/orange (depending on ambient light conditions) and immediately quench in warmed oil. Usually I am looking for a high hardness and don't care if it is a bit brittle. I check hardness with a file - - it is "skitters" off, it is hard. If it bites in, it isn't. But if I do care (like a hunting knife), I'll anneal it (that slightly softens the ultimate hardness but reduces the chance of it snapping: start with a shiny surface, slowly add propane heat until the surface starts to change color. I usually go for a light straw color. I'm talking about the surface color and am not referring to it glowing. Alternatively, I'll look up the annealing temperature and then put it into a toaster oven for a period of time (like 400 F for an hour) based on what I've looked up.

I've found that for the things that I do, that it isn't all that critical. I often use old files to make high carbon steel cutter inserts for my wood lathe. They cut well, sharpen well and don't dull particularly quickly. Occasionally I'll use a HSS like A1, O1, 5160, etc.

[Richard Coers]

How much did the machinist charge, and how many hours a day does the bandsaw run? Could be that the cost to have the machinist make a couple more and use as is will be lower than a heat treat. I'd suspect in the average shop, what you have right now will last for years. You see I'm 67 and have altered my thinking on "lifetime" fixes.

[Bill Dufour]

I wonder what is the biggest carbide insert that can be bought with a center mount screw hole? Or maybe mount a few square ones next to each other. I think my Start Rite bandsaw uses square inserts as blade guides. It pushes the blade into a straight path with the narrow side of the inserts
Bil lD

[Lee Schierer]

Find a local machine shop that makes parts that require hardening and see if they will piggy back your order on one of theirs.

Or

Depending upon what level of hardening you want to achieve, you could do it yourself doo a search for: how to harden steel with a torch

[Mark Gibney]

Brice, I previously watched some videos online in which a hunting knife was heat treated, and it was a slow and involved process, with repeated heatings and cooling, before the tempering.
If you're saying I can heat the pieces one time to the Curie point and then cool them in the warm oil (the point of the oil being warm was made in the video, I remember) and if they pass the file test, that they are good to go, then I'm inclined to try it.

Richard, I've been told by Dan at Davis & Wells that these thrust bearings won't last at all unless hardened. But I like the way you think.

Hopefully in a couple of weeks I'll be able to report back how this panned out.