How can I drill a hole in a planer blade?

[45nut]

I am trying to affix scales to a couple knife projects , I had a planer blade I cut in 3 pcs and I don't know what it is but I know it's tough stuff.

I have tried carbon, carbide, Titanium "TIN" coated,,, everything just spins and doesn't bite into this stuff. Any help would be appreciated.[smilie=1:

[leftiye]

I am guessing that you cut it into three pieces with an abrasive disc? That stuff has to be exceeding hard to resist carbide (which will drill out broken taps). Only suggestion that I could make is to anneal it where you want to drill. I'd use a small acetylene welding tip- big enough, but as small as will provide enough heat. Make a red hot spot where you need holes. As long as you don't get your edge hot, the toughness gained by the annealing will be an advantage. The blades may actually be brittle if they are that hard. One other thought, if the surface has been nitrided (case hardened), then use a dremel with a round grinding stone, and grind off the surface prior to trying to drill.

[waksupi]

Ken, I have a pile of planer blades I got from one of the local lumber mills. I tried annealing them in my forge. No joy. Then, I tried blowing holes through with the cutting torch. Still not real satisfactory. These things are made from what old blacksmiths call blister steel. Would make good hubs for hell. I'm also curious if someone has a good method. The only thing I have realy been able to use them for, is hide scapers.

[longbow]

Well, this one might take awhile but it may work if you don't want to anneal, drill then re-heat treat - you could also locally anneal the tang which wouldn't be a bad thing.

Anyway, my dad told me that in "the old days" he used to drill through glass by using a brass or copper tube filled with valve lapping compound. As it spins in the drill or drill press the lapping compound wants to escape so refreshes itself as it "leaks" out between the tube and glass - or in your case planer blade.

Like I said it may take a while especially if your blade is much over 1/8" but it should work. This stuff is hard and removes metal from valves and seats. You would probably want a coarse grade to work faster.

[45nut]

Yes, i cut it with discs...took a whole one to cut that blade twice. It will grind ok against heavy belts on the sander to shape it and since I do not need round holes anyway I may just grind slots in the shanks big enough for the screws I will be using.
The slots will be covered by the scales anyway.
I do not have any welding gear or experience so my options are limited there. It certainly will hold an edge though.

[versifier]

As long as the hole is big enough for the pin or screw rivet, it doesn't have to be a real tight fit if you are floating the scales with epoxy. I always leave the scales oversized for the glue-up and pinning/riveting, then I do the final shaping of the handles after the epoxy has set up in clamps at least overnight.
I would first try spot annealing, but if yours is as Waksupi has found, then I agree the only real option is oxy-acetylene cutting to make the holes. I doubt even carbide will do much except squeal as it skates over the surface. Normally, with tool steel and some stainless, after grinding the profile I have set just the blade in water with the tang sticking up and heated that until red hot with a plumber's torch to drill the holes. Sometimes pre-ground and polished blade blanks come undrilled and pre-hardened, necessitating annealing either the whole tang or just in the places where the holes need to go. The inside of the tang doesn't need to be pretty, just the outer edges that show between the scales.

[Johnch]

I have cut holes in hardened steel with the shops Plasma cutter

I have no acess to it right now
Might use it in a week or not for another year

But you might fine someone local or on here that has one
A lot of weld shops have them

John

[357maximum]

Ken my suggestion has two parts

1st anneal the spots to be drilled
2nd part involves drilling the holes with a really accurate 17rem stoked with high vel j-words ...you can figger out the rest.

[Bad Water Bill]

Ken A suggestion from an OLD rockhound. Build a putty dam around the spot you want to drill. Fill the dam with water add some of the silicone carbide grit from your cutoff wheel and place the works on your drill press. Insert a piece of rod of any type in the chuck and run at slowest speed. Raise up on the handle every 15 or 20 seconds to allow new grit to get under your rod. Should be done in 2 or 3 min. It works on glass ceramic tile and even S H M B O s emerald ring . Arr of these items are mucm harder than any metal BWB :castmine:

[44man]

The grit is the best idea. I have run into air hardening steel that will not anneal no matter what.

[Bret4207]

You can get carbide grit from industrial supply houses or Brownells. Thats basically how the Eyptians cut the smooth surfaced stones to build the Pyramids- a string, some water, some sand and a LOT of sawing back and forth.

[exblaster]

Has any one ever tried a spot welder for annealing? It might work. Sort of like induction heating.
Exblaster

[Jon K]

45nut,

Let your fingers do the walking.

Find a local community college, ask the Machineshop instructor if they have a Tap Disintergrator, and ask if they have the appropriate size anode rod you need. If not maybe he knows a local machine shop, that can help you out. The machine will burn the hole you need, the size you need. Clean & neat.

Jon

[longbow]

Just another quick thought if you are interseted in heat treating and or annealing on the cheap.

I made a very small propane furnace out of a 1 gallon paint can and made the torch from 1/2" copper pipe. The orifice is a short piece of 1/8" OD copper refrigeration tubing cut with a tubing cutter and the bore opened up with a 0.025" oxy-acetylene torch tip cleaner. The most expensive bit was the insulation - 1" thick by 2 square feet cost $25.00. The furnace will get the blade to an orange colour but the paint can label didn't burn off!

Works like a charm and I started forging a knife blade out of a planer blade to show the kid how to do it

I also use it to forge and heat treat tools, reamers, etc.. It isn't big but it is cheap and it works great for small stuff.

I had some pictures but I don't see them on the hard drive anymore. I can take some if you are interested.

Here is a website with similar equipment: http://www.hal-pc.org/~lwhill/burner.html

And another: http://www.backyardmetalcasting.com/oliverburner1.html

And another: http://metalcast.boorman.us/reil_1.html

And another: http://ronreil.abana.org/design1.shtml#Mongo

Yet another small and cheap: http://www.paragoncode.com/shop/micro_forge/

There was another site I can't find now but anyway the guy uses a mig welder contact tip for an orifice.

Hope this helps.

[waksupi]

I should send the commercial mill planer blades around to all you guys, to take a shot at drilling those tough SOB's. Like a mailing list, as one would be sufficient. Common practices will not cut these. I've heated them in the forge, well beyond my usual forging heat, and can barely shift thier shape, until I am at the level sparks (carbon) are coming from the metal. These ain't no Black and Decker planer blades.

[KCSO]

Those blades take a furnace to anneal and then yo have to re temper the whole blade. They need to heat soak at anneal tempreture (different for different grades) for 1 hour in a controled furnace. Then they have to be slowly cooled in the same furnace for 6 hours. Then you drill and shape and THEN you re harden and temper. Then when yu are done you have a blade you can't resharpen in the field? I much prefer 1095 or 5156 for blade stock as it's easy for us old timers with a pot forge to work.

[leftiye]

JonK is right about the tap disintegrator. That or an EDM machne will cut a hole easily through anything, even carbide. A cutting rod on a stick welder should work also, as well as maybe a TIG used without filler rod, maybe.

[beemer]

What you probably have is hi-speed steel. We use a lot of it in furniture manufacturing for planer blades,router bits,profile heads and carving cutters,or at least we did before plywood took over.It was made for high speed high production work and is very hard and brittle. A piece short enough to make a knife will break like glass and is hard to sharpen without a grinder. We had plenty of it around but nobody had any use for it. I had a carving cutter made to fit a carving spindle out of the stuff. It was weird, you could cut hardwood all day but pine would dull it very quickly. We always thought maybe it was the rosin and knots.
beemer

[GLL]

A Plasma Torch will do the job in seconds then clean up the hole with an abrasive point in a die grinder ! :)
:)

Jerry

[Russell James]

Mate,if u dont have access to much welding gear, forge etc, see if someone has a small arc welder and try to get them to "lay" welds around the area u want to drill.Then grind it off and try to drill it. I have used this before on some very hard steels and it has worked ok. A bit of trial and error, but is well worth the effort without to much outlay.
Hoo Roo from Down Under .Russell James.

[TCLouis]

plasma arc, laser, abrasive drill technique.

I have made several knives with planer blades and I have not drilled any of them
T-88 adhesive on the plates and on a clean blade and some I have were made in the 70s.

I have not abused them and they still do well.

[db2]

Hey waksupi, PM on the way. I can play with one at work and let you guys know what happens.

Shane

[jhrosier]

45nut,
Check your yellow pages for a shop that does laser cutting of steel.

[Linstrum]

As TCLouis and others have already said, one way is to use plasma/an arc welder, I have done it hundreds of times with my welder.

If the hole does not have to be precision and round, use a carbon arc rod in an arc welder and burn a hole by striking an arc then holding the rod just above the spot and let 'er rip. Takes just a few seconds in 1/4" thick steel sections. For obtaining a small carbon rod I take a #2 pencil and light it on fire and let the wood burn off. The carbon rod unfortunately will get white hot in just a few seconds and burn off, so it has to be monitored. After the hole is done, take it to the bench grinder and grind off the boogers and blobs. If you want a large hole use 1/8" E6011 or E6010 arc rod to burn the hole using reverse polarity or AC. After the hole is burned through, a chain saw chain grinding tool in a Moto Dremel can smooth out the inside of the hole.

Hope it helps.

[db2]

OK I recieved the blade from Waksupi. First I tried to drill a 1/4 hole with my drill press at home. Yup, I am sure you all guessed it, that was a waste of time. Did not cut at all and wiped the drill point out. Time to be professional about this. I cut it into three pieces. I Rockwell tested one piece as is and it measured 58 Rc. For those who do not know a gage block measures around 55 Rc, a good quality drill bit is around 60 Rc. HSS is not going to cut this stuff. So then I annealed the second piece by heating it to a cherry red and let it air cool. I wished I had some sand or lye to let it cool slowly in but, I thought at least this will show some improvement. Did someone mention this stuff is hard? Well, it tested at 67 Rc!!! OK boys this stuff is not your normal tool steel. The only steel I can think of that air hardens is "A" series tool steel. I am sure there might be others that I do not know about. How hard is 67? Well, a carbide EM measures a 70 Rc. Hubs of hell? Well not quite, but it is knocking on the door. I did get a hole thru it using a 1/4 inch uncoated carbide drill but, it was not going to make another hole. I used a bridgeport at about 500 rpm. There is coated carbide that puts the hardness over 80. That might be the way to go but, it is hard not to mess up carbide when manually drilling it has a tendency to break when breaking thru the back side of the part. Plus it is not cheap. I am still playing around with it. I am thinking about trying a ball nose EM. When I get some more time I will post it here.

db2

[45nut]

This has turned out to be a very interesting thread, my own experience is similar to db2's here, no matter what drill bit or speed I tried the steel just laughed at me.
I cannot "just" go down to the college or machine shop/welder since I am without the funds nor the ability to just travel lightly. A ten minute drive results in tremendous agony that persists for days afterward so I must just make do with what I have.
In this matter I tried grinding a slot in one handle and in the other two I will just use a blade in my angle grinder to slice them into a traditional tapered tang and make do.
I am not fluid with cash to attempt the other methods nor will shipping them out and back be financially wise, when you are trying to survive/endure on less than about $300 a month options are few and since there was only one piece of steel to deal with anyway I will just move to more manageable blanks.
I just hope there was only one of those planer blades to deal with.

[leftiye]

Just for thought exercises- because if you do this you'll have to re heat treat it. How about annealing it in a furnace where the heat is raised slowly. Then when temp is reached it is soaked, then lower the temp 50 degrees every half hour or something like that.

[Red River Rick]

Most reputable tooling manufacturers have a line of "HY-ROCK" solid carbide 2 flute or spade drills designed for drilling 40+RC hardened steels. They are definately not cheap, but work very well in CNC equipment due to the ridgitity of the machine.

High spindle speeds are required (4000+ RPM) in conjuction with a light feedrate and a shallow peck. Coolant is a must due to the tremendous amount of heat being generated.

No problem drilling 62 RC D2 or A2 Tool Steel, HSS as well. I'm sure that the knife blanks that are question would be no problem. I'd give them a try.

The key to using solid carbide tooling is Rigidity and Cutting Speed, hence it's use on almost all modern CNC equipment. Using solid carbide tooling (EM's) in conventional equipment almost always end up in premature failure because they just aren't rigid enough. Sloppy quills, bad spindle bearings, loose ways, etc, transfer vibrations to the tool causing the cutting edges to chip and eventually become dull and then fail.

The other alternative is Wire EDM. You can now "Zap" an 0.008" dia. hole thru anything that will conduct electricity up to 12" in depth. The wire is then fed thru the hole and the operation begins.

I've seen a dime stood up on edge and have a 0.008" hole punched thru it, they then proceeded to cut the dime in half.


db2:

Try running your Bridgeport at a much higher spindle speed (2500 - 3000 rpm), use a 4 - flute solid carbide EM and see what happens. I know already that trying to use a ballnose EM won't work. Their isn't enough chip clearance on the end of the ball and all that'll happen is everything will plug up and light up like the "4th of July Fireworks".

Just my thoughts.


RRR

[grumpy one]

In case nobody has already posted this, there is an el cheapo way to drill holes in spring steel in a home workshop, though it would be stretching the technology to use it in this case. All you do is use a sharp masonry drill at high speed, keeping the drill tip wet with cutting oil. As soon as you have a bit of an indentation in the part being drilled, you keep that recess full of oil. Don't let the drill tip heat up or you'll melt the bronze holding the carbide flutes on the steel drill. You have to keep stopping to check that the cutting edges are still sharp. You can sharpen them if they are only slightly rounded by using very, very light pressure on an ordinary silicon carbide grinding wheel, but of course you'll blunt the exposed surfaces of the wheel so you can't remove much tungsten carbide that way. Wheels made for sharpening tungsten carbide have a much softer bonding agent to allow rapid wheel-wear so new surfaces get exposed all the time. Nevertheless I use ordinary gray-bond silicon carbide wheels for all my touch-up sharpening of tungsten carbide. The el cheapo approach is my natural forte.

[ANeat]

I work in a pretty large machine shop and everyone has touched on about all the techniques. If I had the material I would try the solid carbide drills first, then perhaps the burnout machine or EDM.

We do some barrels for injection molding machines that are heat treated tool steel with a sprayed in carbide liner. Those go to the EDM[smilie=1:

[db2]

Red River Rick, I thought about running that speed up but my concern was the rigidity issue. At higher speeds rigidity becomes a bigger issue. There is not a doubt in my mine that one of the CNC's can do it. I will try the higher speeds just to see what happens. Yes, there is not that much clearance on the end of a ball nose, I did not know if I would have issues with the corners on a standard bottom cutting EM maybe something with a .03 or .06 radius might hold up.

A die sinker, or wire EDM would work easy enough. I thought I could let one of the laser guys take care of it but then again I am wanting to find a way that I can try to replicate at home.

Grumpy one, I will try the masonry bit idea. Didn't even think about that.

I also want to try the diamond dust idea. If it works on granite it should work on steel. Plus I've never done that before.

I will have more time this weekend to play with it.

db2

[Buckshot]

................I'd have to think the planer blade would have to be HSS wouldn't it? There are quite a few different types of HSS too, with or without cobalt it can be some very tough stuff to work, short of abrasive saws :-) I used a 5 flute TiAIN coated carbide endmill to cut a single 1" long flute in a .375" OD HSS drill blank, and it was a booger. I'd think trying to drill a hole in HSS would be even worse merely due to the way a drill bit cuts, regardless of what it's made from or what it's coated with.

................Buckshot

[Red River Rick]

D2 Tool Steel (air hardened, 67 RC max) is pretty tough stuff. It's wearability is phenominal.
Atlas Alloys uses the trade name of "FNS" denotining it's D2 material, in my shop we refer to it as "F#@!n Nasty S*^t".

On a machinability scale, O1 being 100%, D2 comes in at 45%, its the worst. Even annealled, it measures on the RC scale about 35. Once hardened, it's the worst to work with. We have special grinding wheels on our surface grinders specifically for D2. Any thing else just skates across the work piece burning & smoking, glazing up the wheel.

Because of D2's high wear resistance it is used for commecial planer blades.


Buckshot:

Your right about trying to drill a hole in HSS with a conventional drill, no matter what it's coated with. A stick rubbed between ones hand with some sand as an abrasive would probably provide more positive results.

The other alternative may be waterjet, with the added polymer abraisive.


RRR

[hiram]

You can try spot annealing with a car battery. This was one method to soften a small spot to drill and tap a springfield receiver. Clamp a heavy wire to the blade and attach to positive terminal. Attach a heavy wire to the negative and then touch it to the blade where you want to soften. The spot should start to glow red from heat and soften.

[scb]

I had someone relate this method to me years ago. I've never tried it so I don't know if it works but it's fairly cheap and it might even work. It involves chucking a brass rod in a drill press. Putting valve grinding compound on the part you want to cut a hole in and then then bring the low rpm brass rod down on the part. I think it would be a very slow process tho. Steve

[jar-wv]

I have used a carbide burr with round head to cut through broken center drills and taps. Put it in a die grinder and give it a try.

jar

[grumpy one]

I have used scb's method to drill glass. It works, but it is indeed very slow. Don't use steel tubing, use copper - the working principle is that the grit embeds in the soft copper and rotates with it, so it cuts the glass (or hard steel) rather than the copper tube. The tube does wear away though, after a while. Doesn't matter of course, you just keep drilling anyway. Don't expect the hole to be any particular size except "bigger than the tube". I recommend tube rather than rod - that way you only have to cut out an anulus not the whole area, plus you don't have the problem of low cutting speed at the center.

[leftiye]

Nother way that should work- They make diamond drills for glass (looks like a hole saw). Probly be real good if you kept the operation wet so they didn't plug up. Or a little oil might keep the diamond grit broken from the drill in the hole and doing some good. You'd need to be gentle with the pressure so as not to break down the diamond right away.

[Bob Krack]

In a previous life I worked in a sawmill as a millwright. Planer blades made some of the very best scrapers ever! BUT - they had to be "ground" to size or length, couldn't be cut with an oxyacetylene torch!

One of the old timers there made knives from planer blades. After I retired, we remained friends and he explained to me that he drilled the rivet holes with a plain old masonry bit.

I never saw him do it and have never tried myself but I learned an awful lot of things from him over the years.

Vic

[woodman51jfk]

cobalt drill bits.........I modify planer blades, jointer blades & plane irons regularly, sometime on antique machines, where annealing would compromise the tool's integrity........just my $.02 as a neanderthal woodworker.......

[Ricochet]

Spot annealing isn't going to work with an air hardening alloy.