Steak knife? Zombie knife? Make this custom FOOD blade attachment for your oscillating power tool.
DISCLAIMER: This is Fn dangerous to make as it is to use. Don't try this at home.
Step 1: Mechanical details...
You need a few things:
First, your oscillating power tool. You might notice there are several models and makes out on the market. I think it's proliferation was due to the expiration of the patents of a power tool that had it's blade move back and forth about 3 degrees in a rapid motion. I can say it does have its uses when you need to cut something in a confined space where you can't get in a tool like a reciprocating saw or just need to nip something off whether it be wood, metal or drywall.
Which brings us to this, the only blades available are to cut or scrape wood, metal, drywall or other stuff your house may be constructed of. There is no Food blade or specifically one to cut steak.
I wasn't about to forge my own blade so I took a pre-made steak knife. You can keep the handle on it since it will not get in the way.
You need a method to fasten the steak knife to your worn out or real oscillating tool blade. You can do rivets or nuts and bolts.
I used two #10 bolts with nylon lock nuts. I knew that there would be severe vibration so the nylon bearing inside the nuts would keep the nuts from loosening. You could also use those regular split lock washers with a nut.
You need to drill the appropriate holes to attach the steak knife to the tool blade. I just used my cordless drill with a 3/16ths inch metal bit. I just eyeballed the drill size that covered the bolt thickness. I could always use a reamer or go back with the drill to enlarge it a bit for the bolt to fit through. It would be nicer and safer to do this with a drill press.
Step 2: Make some noise...
See how your tool blade will attach to the steak knife.
I wanted it to be at an angle so it would be ergonomic to use on the oscillating tool.
Mark the spots where the two bolts will go.
You should really center-punch or dimple the center of the hole so your drill can grab it without slipping when it starts to drill. Even those shark-tip bits could use help on hardened steel.
Clamp your piece down. If the drill gets caught, you may lose control of the thing causing some bodily harm.
I gave the drill hole a shot from my can of lithium grease spray nearby. You should always use lubrication with drilling metal since it can get up to high speeds and get hot ruining your drill bit.
Drill with slight pressure so you don't break the bit and you will see some nice shavings come off and possibly a stream of smoke.
Make sure you wear eye protection and clean up afterwards so you don't have little bits of metal all over the place.
Drill your two holes.
Step 3: Get it together, right now...
Clean off all the parts for assembly.
I just washed with dish soap to get all the parts squeaky clean and ready for food contact.
Now here is another dangerous operation.
Attach the bolts and torque them down.
I should have used a nutdriver on one side instead of gripping it freehand with the pliers.
The working part of the steak knife is still exposed and any slip of the screwdriver would be bad.
Those nylon lock nuts do take some force to get started and to finish off so the screwdriver did pop off a few times.
Once the two mounting nuts are secure, reattach the tool blade to the oscillating tool. Orient the blade so it will be easy to use with the tool.
Step 4: Get a buzz on...
Fire it up.
It was pretty wonky at its lowest speed setting and I dare not push the boundary.
I should have done the steak carving on a wooden cutting board instead of in the plate. I am wondering if I ate some ceramic chips for dinner. I guess I will find out later...
This might work wonders for turkey carving but you should really modify a reciprocating saw for that.
So what did we learn?
The FOOD blade was not engineered as a balanced unit and the tool was probably not designed for a blade to be an outrigger type. I did feel the oscillating tool blade after use and it did seem a little warm. I think it picked up the heat of the motor from the excessive vibration of the offset blade. Changing the blade position did not help. Change the blade instead.