You know that saying, "when the only tool you have is a hammer, every problem looks like a nail?" It's sorta like that. When you have a machine that's accurate to thousandths at the worst, everything looks like a project for it.
At some point a couple of months ago, my favorite spatula broke. This is not an exotic, gourmet chef kind of item, it's a silicone rubber, flexible blade on a plastic handle. It just worked perfectly for ice cream making, something I do every four days. The handle goes into the silicone blade to hold it in place; there's what looks like a rectangular opening in the silicone blade and a rectangular piece of plastic that goes into it. It's kind of like woodworkers would do to make a blind mortise and tenon joint. Does the tenon-like piece on the handle have barbs or something on it that holds the soft blade? Maybe, but I don't really know because I never got to see it apart. Instead, the harder (and more brittle) plastic snapped off where it went into the soft handle.
Sure I bought a replacement, but I couldn't find one in the local store that felt like the one that broke. The broken one was better, hands down. I tried gluing the two halves together. That broke again within a couple of weeks.
The two parts sat on a counter where I saw them every time I walked by.
Every time I looked at them, the background processor in my brain thought of
how to fix it. Without telling me.
I suddenly had the idea to create a joint by putting something like dowels in one piece and drill matching holes in the other. I measured the plastic piece sticking out of the silicone rubber at .630 wide and .180 thick. I did some edge finding with my laser edge finder and made an XY coordinate reference system. With the hard plastic broken off in the soft silicone piece being 0.18" thick, plain old wooden dowels wouldn't work. All of mine are twice that in diameter. I looked at toothpicks and they were too small, like 1/16". Then I remembered I have a box of 1/8" dowel pins. Instant tenons for 39 cents.
Setting this up so I could drill two parallel holes straight into
the plastic, holding the position to within "a few" thousandths was a bit of a
pain. The two blocks with three holes on each end are called 1-2-3 blocks,
because those are the side lengths: 2" wide, 3" tall and 1" thick. Behind the pin on
the right is a triangle sticking up. That was a piece of scrap aluminum to
help clamp the silicone rubber and keep it from moving in the vise. I should have cut it off, but it honestly didn't get in the way.
The handle was worse to deal with. It was too long to put in this position to drill and far too curvy to get it to hold still while tightening the vise. I had to clamp it to the side of the vise with a woodworking clamp and position it all by hand. All to drill two holes in the handle that would allow me to glue the pins in both halves. It's not centered, but the handle holds the blade.
This was before I glued it. I drilled the holes in the handle .003" oversized and got a generous amount of glue in there.
The overall view is this:
(That clamp in the background, wooden handle on the right, is how I held the handle to the left side of the vise.) While I'd be completely unsurprised to find that the parts are created in CAD and CNC used to make the mold, this is the only CNC-repaired spatula in existence. At least that I know of. Now where did I leave that number for the Spatula Hall of Fame...?
I know the feeling. SLW has a very nice solid walnut bedroom set. It cost her a bundle, and is something that can be passed down. The handles on the drawers are a pot metal casting with a slotted wood cover over it. One of the drawers had the mounting holes for the handle about "this much" too close together, making you (attempt to...) flex the pot metal part when you install it. The *right* way to reinstall them is to take off the mounting hardware, put it all together, and then bolt it back on the drawer. SLW tried to pry it back into place, and of course it snapped. I wound up drilling a hole into each broken piece, then I cut the head off a 4-40 machine screw, and JB Welded all of it back together.
ReplyDeleteBTDT- I once spent about 2 hours in the shop fabricating a dustpan that I could have bought for about 2 bucks. But mine is all that a man could ask for in a dustpan! Sigh.
ReplyDeleteCan't tell you how many times I've told myself to 3D print one, but not yet.
DeleteLegion are the inexpensive household detritus of which I have labored - sometimes ingeniously - to the intent of restoring to service.
ReplyDeleteFor this spatula surgery, I would have drilled undersized into the handle. The dowels (pins) would be bits cut from a wire clothes hanger. Heat the wire to mate the two halves. The wire pins would be splayed in the silicon rubber.
Then I would spend some amount of time over the next few days thinking of alternate methods useful for creating a superior spatula. Using only materials on hand, naturally.
Nice handle repair! Now, how about your ice cream recipe and method!
ReplyDeleteIt's easy but it's keto: high fat, and low (or zero) calorie sweeteners. Mostly heavy whipping cream. Some people can't deal with that.
DeleteStill want it?
Yes, please! I am mostly keto as well. cboydfl4045atgmailcom
DeleteSending a write-up to your email address.
Deletetry it with an anterior tooth that's snapped off at the gumline - your "dowel" has to be centered running down at least 2/3 the remaining root structure (and you're dealing in tenths of a millimeter) - sometimes (where possible/if reasonable) an implant should be considered.
ReplyDeleteNot only that, but on my milling machine, that piece cannot move. It may be done to the tolerances than you describe but that's because of the properties of the plastic and silicone. On metal, holding 1/10 of a millimeter (.004) isn't that hard. On a living, breathing person, not so much.
DeleteWhat you describe is more like artistry, more like sculpting a lifelike head than machining. Besides, I couldn't do that to myself.
I modeled up a seed planter to use in the greenhouse and then 3D printed a bunch of them, when I could have bought them on Amazon for thirty cents. I understand the urge to justify the tools you were foolish enough to buy.
ReplyDeleteSpatula City! Spatula City! Spatula City!
ReplyDelete(Anybody get the reference??) ;P
I almost included a link to it.
Delete