Re-working pry bar

I ground the ends of a Wonder Bar clone to long thin tapers for prying off molding.

--jsw

I just used a file on my Stanley 12 inch Wonder Bar. Mine wasn't that hard, easy enough to file on. Tweaked both ends so I could loosen redwood siding and trim boards, leaving minimal marks in them.

I've done the same with several other pry bars too using different files to get at all the needed places. They kind of suck, way too roughly shaped for that kind of work as sold...

Different application; I have a piece of steel forged from 3/8 x 1 bar such that it tapers to blunt 1/16 over about 6" and oval in cross section. It came from one of those garage sales held to clean out "Granpaw's junk" and I discovered it to be the handiest tool when dismantling with a view to salvage for future refference such as separating two 2 x 4 's that have been securely nailed together.

Thanks for the replies, but if I still wanted to forge shape it, is there a required process?

Well, I guess the answer is it depends. Is it a work hardened steel or a heat treated steel? Or is it just a hard enough alloy to do the job hot rolled and stamped to shape while still red?

Nail bars aren't $5 anymore, but they are still cheap enough to destroy a couple if you just want to try it.

Rehardening and tempering it is the tricky part, and a very good reason to grind a commercially hardened tool to shape instead. You can practice on a discarded circular saw blade. I annealed one, cut it into strips and rehardened a piece as hard and brittle as glass.

The few times I've hardened a tool I tempered it around 700F on an IR meter, and if it was too soft to cut steel I rehardened it and tempered cooler. That's less work than making another if it breaks from being too brittle.

The thermocouple adapter on his DVM looks like an expensive Fluke

80TK. The inexpensive TM-902C thermocouple readout I would have suggested is out of stock at Amazon. Omega's GG-K-24 thermocouple wire is a good choice to make your own. Wood stove gasket cement will bind the cut ends of the insulation. Do you have or know someone with an acetylene torch to fuse the end?

When you heat the end with a torch to reharden it part of the shank will lose its temper. Perhaps that won't matter for a prybar for molding. Good luck with it.

--jsw

No TIG required. The old hack is a 100-watt incandescent lamp in series with the TC and a carbon rod from a D-cell, across 110 Vac. The TC wires are twisted together, heated in a flame, and dipped into borax.

The arc from the lamp turn-on surge will weld the ends of the wire together. Tap the weld bead with a hammer on an anvil to crack the fused borax off the bead.

What also works is a charged photoflash capacitor discharged through the same twisted wire and carbon electrode.

Commercial TC welders are the photoflash capacitor et al, but with an argon blanket and no borax.

Joe Gwinn

How do you safely clamp everything into position?

--jsw

I think will play with a saw blade - easy way to get some experience.

I annealed-hardened-tempered something once, but I think that its hardness & temper had a wide acceptable range and was much easier than this is looking to be.

Cool chart.

I do have a thermocouple meter (for casting), but even with it I think that this re-forging is a bad idea. Thanks for giving me enough info to see that!

Bob

Cool stuff!

Just to clarify: the carbon rod is touching the end of the TC?

Bob

This concentrates on making smithing, woodworking and stone sculpting tools:

--jsw

I used to design and build custom power equipment of that ilk, and last week found a 50VA 120/240/480 transformer for my current HV project. It was always difficult to find high voltage, high temperature insulation that could take mechanical stress.

Fiber gasketing from the auto parts stores chars and smokes above

600F. Teflon emits nasty fumes if overheated. I have some carbon fiber scraps that withstand 2000F but it conducts electricity. Fireproof ceiling tiles would be good thermal and electrical insulation if they didn't fall apart so easily, same with wood stove door gasket cord. Fiberglass cloth melts in a flame, which at least is useful to seal the cut edges.

I have some Fel-Ramic 2499 exhaust gasketing to try the next time I need high heat resistance, but it has conductive wire reinforcement in the center.

--jsw

I took a look at my smaller bar. It is Enderes D-26. Must have bought it around 2002. It looks very similar to the linked to bar above. Measures

10 inches long. It is illustrated on page 26 in this catalog (30mb):

I preferred the Stanley Wonder Bar. It worked better, left less marks in the wood. Since then I've bought a Vaughan Super Bar too, think it's the 21 inch model:

The flat head on it is very similar to the Wonder Bar and seems to work much the same. It has less of a v-notch in it for pulling nails though. I tweaked the end of that bar too. It wasn't all that bad though if I remember correctly.

I try not to use the Wonder Bar for rough work or hit it with a metal hammer...

I've seen another bar similar to the one you linked to that has a really wide flat head and no nail notch. It might be in the Enderes catalog somewhere. Didn't look through it too good yet. I'll find an image of it if it interests you...

I think that chart only applies to plain carbon steels. I was just looking for information about tempering EN24 (4340) and the information I found gave a far higher temperature range for tempering, the chart giving the various properties curves and temperatures and ranged from

450C to 650C and needed a longish soak time compared to carbon steel. I made a few replacement pipe cutting rollers from EN24 and when hardened and tempered according to the carbon steel chart they crumbled, now I need to take the remaining one and temper according to the new information and see how it performs, fortunately I have an accurate temperature controlled furnace. Just got me thinking that if the alloy effects the tempering temperature that much then trying to temper an unknown alloy is likely to be hit and miss.

Regarding the IR temperature reading how did you assess the emissivity in order to get an accurate reading from the meter.

Thanks - that does look exactly like the one I lost, and am mourning. I can't find a seller for it & have emailed Enderes. If not, I'll get the one at Lowe's & grind it a bit.

My $15 commercial unit doesn't have that adjustment. However it's close enough when aimed at the corner of the wood stove where the thermocouple is. I use them if accuracy matters and to check the IR reading.

Judging heat by color was good enough for many centuries of blacksmithing. In Scouting we stuck our hand where the cooking pot would go and counted to determine the temperature.

At Mitre I used a high quality IR thermometer with an emissivity adjustment but the temperature reading didn't vary much on most electronics materials no matter where I set it.

--jsw

I have the 2pc set, the 15" bars, and the nail pullers.

The nail pullers (multipurpose pry bar) proved to be the best moulding puller of them all. I, too ground the end to be very thin and sharp.

Another smaller bar I use is a 5" flat pry bar, with custom tapering performed by me. Thin and sharp is good.

One of these made it into my BOB:

It's amazingly strong, sturdy, and stainless. (retapered)

The TC is held in a vise, and the carbon is held in an insulated holder which is held in hand. There is 110 Vac between vise and carbon, with the 100W bulb as the current limiter.

The vise should be clamped to a wooden bench, and ideally is on the cold side (white wire in the US) of the 110 v line and the 100w bulb is in series with the carbon rod, so if carbon touches the vise, the bulb lights up, but no big bang.

Joe Gwinn

Yes. See other answer.

I learned this trick in the late 1960s from a Grad Student who was welding the ends of platinum tubes closed using this trick, but using

110 V DC from the University's own 1900-era power plant.

Joe Gwinn