"cutting edge" steel - Fab questions

[RedDirt]

I will be building a narrow bh bucket similar to charlz "narrow bucket" post. This bucket will have relatively light used, eg. not professionally, not daily. My ground is clay with very few small rocks. Like charlz I am going to start out with no teeth since my trenches are fairly shallow (18" 24") and ground is "soft". I'll add teeth later if needed. Cutting edge will be 3" x 3/8" or 4" x 1/2".

My questions regard placing a cutting edge on this bucket.

1. Do I need bone fide "cutting edge" steel stock or can I just use Hot Rolled flat steel and grind the bevel edge myself (taking care not to overheat the metal)?

2. If using a torch to cut a) cutting edge steel or b) hot rolled flat steel, does the heat at the cut destroy the "toughness" of the steel? Is this just at the cut line or does the heat "travel" some distance from the cut and affect the temper of the plate overall?

3. What is the best method to cut a) cutting edge steel or b) hot rolled flat steel to preserve their tough qualities? I have a bandsaw, hand hacksaw, Sawzall, abrasive chop saw, torch, and thin grinder blades at my disposal. I don't know anyone with plasma equipment. I'm thinking a tough (Lenox) bi-metal blade in the Sawzall may be best and least damaging. Like cutting stainless plate, firm, steady feed pressure may keep the Sawzall blade from dulling and case hardening.

4. If using high carbon hot rolled steel and beveling the edge myself should I temper the piece before welding it on the bucket? Before or after the beveling is done?

5. Does pre-heating before or "slow cooling" after welding help preserve the toughness of these two metals?

Thanks for any feedback on any or all the questions above.

 

[Egon]

Use the real cutting edge material. Larger size will be better and make the bucket stiffer. Also put some on the sides of the bucket.

Cutting with a torch works well. Weld as normally but you should be using rod made for the cutting edge. Don't worry about heat. It will all be okay.

At least that worked on my cutting edge but I didn't do the cutting or welding!

 

[mboulais]

Anytime you are cutting metals keeping it cool is required to preserve hardness. Cut with a saw and cool with water. An assistant can squirt water on the blade with a recycled windex bottle while you run the sawsall.

As far as using high carbon steel, yes you can do it. It will be easier on your cutting tools too. Heat treating a cutting edge of any kind involves a couple steps. First is hardening. You will need get the edge very hot, and as evenly hot as possible. Ideally you will heat it until it is non-magnetic, somewher in the bright red range. After reaching that temp quench it with water or oil. Now the edge will be hard. It is too hard though and needs to be tempered. Polish the surface so you can see the colors run in the metal. Heat the edge until it turns medium blue.

 

[DWW68]

REdDirt,
Check around at shops that do repairs on construction equipment. You may be able to find a used up cutting edge from a dozer or something that woud fit your needs. An abrasive blade on an angle grinder will cut thruogh it. When I cut the one that I used, I cut about half deep and snapped it in half. In fact, i think I still have a piece left over that would be big enough for what you need. You could have it but I do not know what shipping would be. If interested let me know how long of a piece you need and I will verify that it is long enough.
Dan

 

[RedDirt]

REdDirt,
Check around at shops that do repairs on construction equipment. You may be able to find a used up cutting edge from a dozer or something that woud fit your needs. An abrasive blade on an angle grinder will cut thruogh it. When I cut the one that I used, I cut about half deep and snapped it in half. In fact, i think I still have a piece left over that would be big enough for what you need. You could have it but I do not know what shipping would be. If interested let me know how long of a piece you need and I will verify that it is long enough.
Dan

Dan,
That would be great; thanks for the offer. What is the cross section dimensions and length of your piece and I'll calc the weight and check shipping. I'll need 38-40 inches long if I do the sides and bottom but only 8-9 inches if I do the bottom only. Something like 3/8"x3" or 1/2"x4", bevel edge on one side is what I'm looking for.

 

[Renze]

Red Dirt, at the company i work, We convert Mercedes Sprinters to light 5th wheel tractors with air brakes and sometimes air suspension.
With the air suspension kit, the original leafs are replaced and thrown away, so i have access to cheap leafs.

Spring steel is allmost as hard as a "real" cutting edge, but can usually be obtained a lot cheaper. Perhaps there is a truck shop somewhere near you that replaces broken trailer leafs every now and then. To them its just scrap, but as abrasive resistant material, it is very economical

Putting these steels into a band saw will dull them within 2 cuts. i had best results with the angle grinder. It takes a bit longer than mild steel but it doesnt wear premature.

 

[DWW68]

RedDirt,
The blade thade I have is 58 1/4" long with bevel on both sides
11/16 thick
5 1/4" one end, 5 1/2" center, and 5" at other end
I was going to use it for a tooth bar but after I received the teeth, I found out it was to thick for me to use.
I attached a picture so you could see it.
For shipping purposes my zip is 14037.
Dan

 

[RonMar]

If this is going to be a light duty bucket, you could just add a re-enforcing strap (4"X 1/2") along the cutting edge and run several weld beads along the edge of this strap(upper part of attached pic), then grind down the welded edge material into a cutting edge(lower part of attached pic). If you lay down your welds carefully, it can require very little grinding to finish the edge.

Ever try to cut thru a weld with a sawsall? it works great in the steel right up to the point where the blade starts chewing into the much tougher weld metal and quickly chews up the blade.

I have had good success with these weld hardened edges over the years, and if it does wear down, it is easilly built up and reshaped.

If it dosn't work, you can always add a "hardened" cutting edge later...

Good Luck

 

[RedDirt]

Thank you all for your replies.

Renze,
That is good to know about the toughness of spring steel. But aren't these usually arched? It would make fabricating something straight rather difficult. I suspect if you were to heat the spring to bend it straight you'd loose the tough properties. They may make good weld-on bucket teeth.

Dan,
Regrettably I think the cutting edge piece you have is too big for my needs also. Perhaps another member could use it. Thanks for the offer.

Ron,
Thanks for the tip. Sounds like this would be worth a try for my lightly used bucket, especially if I can't find anything locally.

 

[Berniep]

I haven't read the other threads about buckets so this might have been covered there. If so I apologize.
First, I was always under the impression that cold rolled steel is a little tougher than hot rolled because it is more work hardened. At least thats what my local supplier told me.
Second, if you have a stick welder you can get some "hard facing " rods and weld some beads on the cutting edge and grind them to shape and have a very hard edge that is as resistant to wear as a genuuuwiiine cutting edge.
Ask at your local welding shop.

 

[john_bud]

Reddirt,

There are 2 cutting edge types available. The one you require is weldable edge. It's the stuff that is on FEL buckets. The bolt on edges are high carbon steel and they don't weld easy. Can be done, but you have to use your Ox/Ac torch and pre-heat the snit out of the edge, weld, heat, weld, heat, weld then post heat and slow cool. The old hands have it down pat, I don't! You can tell you didn't heat it correctly when it cools you hear "rice crispies" sounds and by the time it is cold, a big ugly hunk of the edge may physically pop out. Even real pretty pro quality looking beads. You really don't want those issues attaching the edge to the bucket nor the tooth shanks to the edge.

When you get the weldable edge, you can get them pre-punched for bolt on edge. That's the ticket. Then you can have 2 bolt on edges. One that is flat and smooth and one with teeth. Probably only 3-4 bolts needed.

Good luck with the project.

jb

 

[Renze]

RedDirt, i was telling about the leaf springs because the purpose i personally had in mind, which came to mind when you mentioned buckets and hardened steel...
I have a cutting edge on my FEL bucket but i need some digging teeth.

Some leaf springs are straight, though most of them these days are parabolic because they give a smoother ride.

 

[jwmorris]

I made some "teeth" for an auger a few years ago, I used cold rolled steel, after machining I hardened the parts using Kasenit hardening compound. They have held up better than the originals.

MidwayUSA - Kasenit Surface Hardening Compound 1 lb

 

[MikesTractor]

I made some "teeth" for an auger a few years ago, I used cold rolled steel, after machining I hardened the parts using Kasenit hardening compound. They have held up better than the originals.

MidwayUSA - Kasenit Surface Hardening Compound 1 lb

That looks like some good stuff, so I ordered (back-ordered, not in stock) some. I can see many uses around my shop for it. I hope it don't stay back-ordered too long.

 

[laurencen]

that kasenit is good, easily toughten any material, heat with a torch bright red, dip in let soak, re heat and presto good to go, quench if you want harder, its good because it only hardens the outside even hot rolled steel, one other way is highways or city engineering, the graders or snow trucks have wear edges bolted on, when they wear they are usually garbage, keep in mind they typically have 2 edges and only one gets used, great for cutting edges on buckets,

 

[3RRL]

Hi Ray,
Thought I'd throw in my 2 cents...at least my Humble Opinions.
1. Do I need bone fide "cutting edge" steel stock or can I just use Hot Rolled flat steel and grind the bevel edge myself (taking care not to overheat the metal)?
You state in your opening post your ground is not too rocky and mostly clay an fairly "soft", so I think you could use hot roll or cold rolled steel.

2. If using a torch to cut a) cutting edge steel or b) hot rolled flat steel, does the heat at the cut destroy the "toughness" of the steel? Is this just at the cut line or does the heat "travel" some distance from the cut and affect the temper of the plate overall?
Hot roll and cold roll are not that tough to begin with. I think cutting with a torch or welding on them would probably harden those areas harder than the parent material is. I wouldn't worry about the heat migrating too much. It should be alright after welding.

3. What is the best method to cut a) cutting edge steel or b) hot rolled flat steel to preserve their tough qualities? I have a bandsaw, hand hacksaw, Sawzall, abrasive chop saw, torch, and thin grinder blades at my disposal. I don't know anyone with plasma equipment. I'm thinking a tough (Lenox) bi-metal blade in the Sawzall may be best and least damaging. Like cutting stainless plate, firm, steady feed pressure may keep the Sawzall blade from dulling and case hardening.
Well, the best method IMHO would be to saw it with coolant, next would be whatever you find to work best with what you got. Again, if you're going to use hrs or crs you don't need to worry about cutting pre-hardened steel like a true cutting edge. If you do get some, I'd still try to saw it first then perhaps use a cut-off wheel on your abrasive saw. I wouldn't worry about any loss of hardness since I think regular hrs or crs would work anyway.

4. If using high carbon hot rolled steel and beveling the edge myself should I temper the piece before welding it on the bucket? Before or after the beveling is done?
I don't think you need to worry about that for your usage.

5. Does pre-heating before or "slow cooling" after welding help preserve the toughness of these two metals?
That is always the preferred method to use any time you can. I would recommend you do that if possible. However, there are times it's not practical to do so. If you strip weld small areas at a time and allow ample cooling in between you should be alright.

Like I said, those are my opinions and others may disagree.
BTW, what part of the Sierra's are you in? I'm in them also.

 

[RedDirt]

Hi Ray,
Thought I'd throw in my 2 cents...at least my Humble Opinions.
BTW, what part of the Sierra's are you in? I'm in them also.

Rob,
Thanks for your 2 cents, they're appreciated. Collectively there's a wealth of good info on TBN; great community.

I'm East of Oroville, about 1 1/2 hrs north of Sacramento. Upper foothills, lower mountains, 3000ft elevation. Where are you?

 

[3RRL]

I'm in the foothills below Sequoia National Park in a small town called Three Rivers. I'm only at 1600' elevation but you would think it was up higher than that from the countryside.

Well, when you get your bucket project going, I'm sure all of us would love to see pictures of it. While you're at it, post some pictures of your country side too. I'll bet it's beautiful up there.

 

[SkunkWerX]

For an example of weld-on cutting edges, go here and scroll down a bit:

Loader Bucket Accessories - SSB Tractor

Loader Bucket Accessories - SSB Tractor

 

[Dirtnut]

you should be able to get away with most any steel on that size machine. i am a heavy equipment operator and when i work in the oil refineries no teeth are allowed. so flat stock is welded to the teeth for digging this lessens the chance of snagging or puncturing utility lines it will slide over it. the flat steel last a long time on these big machines corners wear the fastest but they are rounded from the start so there are no sharp edges. it does make it harder to dig something you might want to consider.