How to drill screw inserts in D.I.Y. table?

Hi @timothyleong

That sounds like an interesting project... hopefully we will get to see the finished product here on Bunnings Workshop.

I haven't used those particular Inserts, but there should be a drill size guide on the pack - and the feedback below the product page from users who have used them suggests that they can be fragile, so a cautious approach is needed.

The size of the hole can vary slightly - depending on the softness\/hardness of the timber being used.

Generally, you measure the outside of the Insert's barrel - that is imagine that the threads have been removed.

If your timber is relatively soft, use that as the hole the hole size so that the max amount if thread bites in. If the timber is hardwood, add another 0.5mm so that you are not straining the insert itself when inserting.

You can "measure" by eye - hold up a drill bit behind the Insert to get a good idea of whether it will clear a hole for the Insert's body while also leaving enough timber to grip the thread.

To insert it, especially given the reports of fragility, I don't recommend using the hex driver.

A better way that protects the Insert is to get a bolt of the size that screws into the insert (6mm) and a nut and washer to suit.

Screw the nut part way up the bolt, followed by the washer, and then insert that into the insert such that it occupies all the insert's thread.

Then tighten the nut onto it (finger tight should do).

Now use that to drive in the Insert, tightening via the bolt head. This will ensure that you get it to the correct depth (ie flush with the top) while also protecting the body of the Insert from sheering forces (as would be the case when all the force comes only from the top of the Insert) as it goes in.

Make sure you keep it square as you go, which is easier to see using the bolt and nut method.

You can use a power driver, since this method prevents over shooting the depth (the washer stops it at the correct depth).

I hope that helps.

Hi @timothyleong,

That's some brilliant advice @TedBear has provided. Start with a 5.5mm drill bit if this is Pine, and you might need to go up to 6.0mm if you encounter resistance. Please do not use an impact driver on these inserts, as they will most likely break.

Let us know how you go.

Mitchell

Hi guys,

Thanks for the helpful and really detailed responses.

I forgot to mention that the table is a walnut rubberwood desk. So im guessing 6.omm bit would be better?

My screws are 15mm and the table is 25mm , do I need to drill 15mm into the wood as well?

And also would this drill be enough for the job? https://www.bunnings.com.au/ozito-pxc-18v-cordless-multi-chuck-drill-kit_p0370064

I will definitely try to post photos when im done!

EricL

Hello @timothyleong

The screw inserts are 13mm deep, drilling 15mm deep means that the inserts will sit further into the table. If you want the inserts to finish flush with the table, I suggest drilling only 13mm deep and testing one of the inserts. If the insert does not sit deep enough add 1 millimetre to make the drill hole 14mm deep.

The drill you've chosen is good, if you're planning on doing more D.I.Y projects it's an excellent one to start with.

Please keep us updated with your progress, we look forward to seeing your table assembled and ready for use.

If you need further assistance, please let us know.

Eric

Hi @timothyleong, further to EricL's advice, if you need further depth to accommodate the length of the screws then drill the hole for the insert first at the correct depth for the Insert, then use a thinner bit that is correct for the screw to add depth for the screw. That way the insert should go down to the right depth, while the screw tip can continue further if necessary. Use a depth stop on the bit so you don't go too far. If you don't have one, use a piece of tape wrapped firmly to the bit, with a piece sticking out to the side (like a small flag) to let you know when you're there. (When the dust gets cleaned off the work by the flag. )

Hi there, just an update so far. I drilled the hole on the right with a size 6 drill bit. It felt abit too small for the insert. I then used a size 8 drill bit the drill the hole on the left. I managed to screw the insert abit but now im stuck. Do you have any suggestions how to push in the insert more? And is the size 8 drill just right or too small? Thanks for your help and patience so far!

The 8mm is looking about right @timothyleong, and you couldn't go much larger before the thread doesn't grip anymore. The idea is that the thread cuts into your timber, so there will be resistance when it starts to cut. When you say you're stuck, what's happening? Is it just getting stiff to screw, or has it stopped no matter what amount of force you put on it?

Is that an insert you've managed to get in further down the table?

Mitchell

Noyade

Hello @timothyleong

I used something similar - TaskMaster Code 12243 - 6 X 20mm. But for the life of me I can't remember what the project was.

My external examination revealed they are slightly tapered and if you disregard the outer wood-biting thread diameter, the tubular body is 8.3 mm in diameter at the top and 7.5 mm at the bottom. Mine don't have the flange at the top.

They are of a brittle aluminium construction. I'll type that word again "brittle."

From memory I had to practise on spare wood with various drill sizes and I think in the end I used a lubricant to assist with the 'insertion.'

And that was for softwood.

It's very easy with a 6mm allen key to shatter the top section, and if you do that they can be hard to remove.

Go slow.

Not a product I'm in a hurry to use again.

Best of luck to you.

Hi @MitchellMc so the insert is quite stiff to screw and dosen't move anymore. I feel that it would screw in more if alot more force was added but am afraid to break the insert.

I only tried using a screw driver and allen key at the moment. Im probably going to get a socket wrench and try the bolt/washer and try to screw it in somemore.

I also thought of getting an impact driver but would that be too much to break the insert do you think?

Yeah the insert further up was done by the manufacturer... But im using different legs thats why had to screw in my own.

Thanks @Noyade, yeah everyone stressed that it was brittle too. Do you remember what lubricant you used or what sort do you recommend?

Or do you recommend other inserts? And where I could get them?

Thanks again guys!

Screw-in inserts are by nature quite stiff to screw in @timothyleong. They won't just screw in with no resistance; they need to cut their own thread into the timber as they go. However, I can certainly understand your hesitancy given feedback on them. Perhaps you could try one in a non-critical location to get an idea of whether this will work. As a lubricant, you could use an oil or wax.

Mitchell

https://www.youtube.com/watch?v=ZvcNG6bQcRE

Hi @timothyleong

since a picture is worth a thousand words - I have found a Youtube video which shows the method that I suggested.

Hopefully seeing it done in practice will give you the confidence to proceed.

The interesting section starts at about 2 minutes in...

Hi guys,

I saw that video and I tried that method but without an impact driver. I currently have one insert that is broken and another for some reason the bolt is loose in the insert and wont come out. Im trying to find youtube videos to solve those problems but if you guys have any tips that would be appreciated.

Also one of the holes I drilled was too small, is there any way that I can drill a bigger hole over it?

Once again thanks for all your help!

Noyade

Afternoon @timothyleong

You asked this on the previous page...

"Or do you recommend other inserts?"

Right at the very end of the YouTube video Ted provided above - the presenter made it very clear to buy steel inserts.

I used the aluminium ones mentioned earlier on the underside of a very old bar stool. I replaced the old wood with new plywood and used the inserts to anchor the four legged base. I managed this with an appropriate sized hole (using a drill press), allen key and WD-40. I treated the insert like a metal die, turning one revolution and backtracking half a revolution. Fractured one but in the end managed to insert four of them.

You mentioned above that one bolt (M6) is loose and won't come out - most likely that very soft aluminium thread has been stripped by the steel bolt.

When it came to attaching the back of the stool, I gave up on these aluminium inserts. I used large screws strategically sized and cut with an angle grinder. I just did not trust the holding power of these inserts should someone lean back heavily on the stool.

I would love to see the legs you're going with.

I would love to see the legs you're not going with.

And I would love to know why. 😀

You mentioned the table top is 25mm?

You don't want wood screws?

Hi @timothyleong , the picture you attached shows the nut part way up the bolt used to drive the Insert in.

I hope that at the time you drove the Insert in, the nut was screwed down to engage the top of the insert. That would be essential for this method to work.

As for removing it, If you get a grip (spanner) on the head of that bolt and then tighten the nut against the Insert (& washer), it should all become as one and then be able to be wound out by turning the bolt head.

You may have to retighten the nut as it comes out, if it works loose, maybe even keep a spanner on it to keep it tight as you go.

--- I may have misinterpreted your query - is it the bolt that you wish to remove, not the Insert?

That may be as @Noyade stated, that the bolt has broke the thread. If that is the case, I would still try the method I've stated to remove the Insert, as it won't be usable anyway if the thread has stripped.

How are you going @timothyleong? Did you try a lubricant like WD40? If you continue to have issues placing the inserts, then it would be best to look at other solutions. Your timber might be too hard for these inserts. If you provide some details on the legs you've chosen, I'm sure our helpful members will be able to suggest some alternate fixing methods.

Mitchell

Hi everyone, sorry I havent had the change to work on it recently hence the lack of updates.

So I got the Trotten table from Ikea originally. Its the manual standing desk version. I liked the table legs but wanted to get a much bigger table, a wooden finish and maybe hardwood instead of mdf as I was thinking of using monitor mounts.So I got a desk top from somewhere else.

I think most people recommended using screw inserts and I thought it would be a nice project for myself.

@TedBearOh yes the nut was screwed all the way down when I was screwing in the insert. Yeah im trying to remove the bolt. The insert is pretty much flushed to the table top. And yeah I have given up on the aluminum inserts too.

Thanks again guys for your help. Im going to make another trip to bunnings to get more stuff before I continue.

Keep us updated @timothyleong; I'm keen to see you get this sorted.

Mitchell