Furniture pins and locks

Hi,

may I assume that the pins you've shown interlock with "locks" in the opposing piece of wood?

As an unwelcome comment: What I've found, it is usually easier to remove the pins when taking the furniture apart and putting them back in when re-assembling. That does avoid some breakage The holes wear out, though.

Where you have broken pins, there are a couple of different options...

- These pins are a standard item and you should be able to get replacements at any better DIY-stores.

- Where they have broken, in my experience the wood around the holes is often damaged, so re-using the holes usually requires some repair. I try to get some glue into the cracks and clamp it over night. Then drill the hole out and glue in a dowel if necessary before re-drilling the original hole (lot of work).

- As you suggested, sand the broken spot flat, glue and clamp if necessary, then drill and install dowels about 5cm (2") on either side of the failed spot. This is often preferable to trying to repair the original spot depending on the damage.

- Lately I've been putting my PocketHole jig to work for this kind of repair - instead of drilling for dowels, just drill a pocket-hole from behind and install a screw (this is a variation on the previous one). This method is fast, easy and surprisingly strong.

- The "gold" option: drill for and install compatible pin-and-lock devices in a spot near the damaged spot. The downside is that you need to drill three holes (typically) with a high degree of precision relative to each other. You'll need a drill guide (you don't want to precision-drill with Forstner Bits handheld if you can avoid it), typically three different drill sizes, ... If you have more than one spot you should build or buy a drill template.

- Typically it is better to not re-use the damaged spot for a new fastener, but you might still end up having to re-use the spot.

There are other methods for repair, I guess.

The method you choose depends on the furniture in question (is it a nice piece that is worth the effort?), on the visibility of the spot (can you drill into the back and nobody will see it?) and on the tools you have available...

Hope that helps.

To get the threaded pin out,

To get the threaded pin out, get yourself a screw extractor set. You should be able to find them at the hardware store.

https://www.lowes.com/pd/CRAFTSMAN-5-Pack-Steel-5-in-Screw-Extractor-Set/1000594887

Thanks

I had no idea these were a standard or semi-standard thing. I first bought this desk around 1995. The first time I moved I tried to get the pins out, but couldn't without damaging them too much, so I gave up on that as a solution. But now I think I might be able to buy some replacement pins, that would be easier than using my own dowels for sure, if I can get the right ones. Haven't found them yet, home depot didn't have the same kind of pins, but amazon has a lot of choices that might work.

I'll try the screw extractor too. 

Check a Good Hardware Store

I have seen this type of stuff in all of those little boxes full of oddball hardware items.

Espee over Donner

twist Lock and pins

Home Depot , Lowes, Ace Hardware, (U.S.A ), Menards?  ace Hardware usually have these in bulk

good luck

Back in the US

Might put it on a shopping list for your next trip back here.

Jack

drill and screw

I'd use the existing good ones for alignment and then neatly drill and countersink some new holes and use plated deck screws to make it solid

 for neatness you can measure the spacing of the holes so it looks like it was done on purpose

i prefer plated or ceramic coated screws instead of black ones, they look better

all screws need three different diameter holes, one for the threads that is the width of the core of the screw

one for the smooth shank that is big enough for the screw to fall through

and one for the head, counter sink, counter bore, or no hole flush mount

there are bits that can do all three ant once

many new screws can make the first hole themselves but skipping this step leads to splits, skipping a correct hole for the shank keeps the two pieces from tightening up as the threading action pushes them apart

Plus one for Kreg Pocket holes

Once the pin lock system is damaged, it will be difficult to effect a reliable repair.   Drilling pocket holes adjacent to the damaged pins would be a simple and effective way of getting the case frames back together. 

The Kreg  pocket hole system is a good way of joining case frames together so long as the pocket holes can be kept on a non-visible face.

You can spend a lot on Kreg jigs, or you can spend $14 and get your job done:

https://www.amazon.com/Kreg-MKJKIT-Mini-Jig-Kit/dp/B00065WPP2/ref=sr_1_17?dchild=1&keywords=kreg+jig&qid=1630006294&sr=8-17

pocket hole approach

I don't know  how well the pocket hole approach would work since it's laminated OSB. I suspect the screw would tear out pretty easily, and trying to drill through the hard laminate at an angle might generate a mess too.

But I want to get one of those for other uses, eventually.

There are a lot of different sizes of these pin locks, and I'm not sure I've found a fit, but I'm going to risk $9 on an attempt and see. Plus I need to find a screw extractor set.

  "There are a lot of

Did you try to drill out the remnants of the old pin? If it's soft plastic you might not need a screw extractor. I'd try drilling the center out then stick a screw driver in there and see if the rest pops out. I don't think a pocket drill would be the best choice for this repair. A hidden dowel or biscuit would be neater and easier, (but finding a replacement pin would be easiest) Pocket screws seem to be over used ( like 3D printing) for applications they are not ideal for, I guess folks buy the tools then feel like they need to use them   :> ) .....DaveB

Getting the broken pin out

A thought: A simple and possibly less risky approach to getting that broken pin out might be to drill a small diameter hole (1/8”?) through the other side until you hit the pin, then use a punch or a sacrificial drill bit to knock it out.  An 1/8” hole on the nice side could be filled with a similarly colored caulk, or wood filler, or epoxy.

Pin base removal

Using a drill bit a size smaller(*) than an empty pin base hole, drill out that soft plastic remnant (use a Dremel w/ a cutting bit to lower the height of the pin remnant, until the drill bit self-centers in the hole).  Use a pick to remove the thread fragments, if the bit doesn't grab them when drilling *carefully* to the bottom of the hole.

You could probably thread an intact pin into the hole, and force the old thread fragments loose.

*If you have a machinist's drill index, take a 1/32 down from the hole.  If 1/4", take a 7/32" bit...

Just throwing it out there.

Tim B

I ordered some replacement

I ordered some replacement pins and a screw extractor set tonight, we'll see how that works when it comes (sept 2, due to international shipping).

The surround of the pin is plasic, but the pin is pot metal, in a + shape. If the extractor won't get it, or sufficiently destroy it to get a grip on the rest, I'll try the hole from the other side, I like that idea. I'm not too concerned about looks, but I don't want to make a mess of it either. The laminate is black most places, immitation wood grain on the table tops, so the black will be easy to hide a little hole in.

I succeeded by drilling a

I succeeded by drilling a hole from the other side and punching out the broken pin. I tried smaller holes with nails but couldn't get enough punch, eventually I had to drill a 1/4" hole and use a bit designed for drilling metal to get it out. 

I'm finding most of the broken pins have left the rubber grommet portion sticking out enough that I can get it out without resorting to drilling from behind. The replacement pins I ordered work just fine, and I've used up the first 8 and ordered 16 more. I have two of the five desk parts (3 desks, two shelf units) put together.

All this is just in the way of getting around to model railroading.