Fixing 10mm studding into wood

[robgul]

I need to fix some short (125mm) lengths of studding into some table legs made from laminated plywood (72mm square) - the studs will protrude about 25mm and screw into plates fixed to the underside of the table - see pic of legs with studs loose in the holes. The bottom of the legs will have threaded inserts and feet in TRHC of pic.



Some sort of resin/glue is the obvious - but what is the best sort? The stress on the studs will be minimal. First thought was just the 2-part epoxy in the little dual-cylinder trigger packs from the likes of Poundland . . squirting both parts in the hole, stir with a skewer and stuff the stud in! Or is there a better material ?

I did consider threaded inserts for the tops of the legs but I don't think they would be stable enough.

 

[sams93]

I need to fix some short (125mm) lengths of studding into some table legs made from laminated plywood (72mm square) - the studs will protrude about 25mm and screw into plates fixed to the underside of the table - see pic of legs. The bottom of the legs will have threaded inserts and feet in TRHC of pic.

View attachment 166520

Some sort of resin/glue is the obvious - but what is the best sort? The stress on the studs will be minimal. First thought was just the 2-part epoxy in the little dual-cylinder trigger packs from the likes of Poundland . . squirting both parts in the hole, stir with a skewer and stuff the stud in! Or is there a better material ?

I did consider threaded inserts for the tops of the legs but I don't think they would be stable enough.

I think I would do similar to what you are suggesting for that. Is there any reason that you couldn't use some large threaded inserts (like these), firstly installing the inserts which you could glue in too, and then glueing the studs in place.

I have never had much success with the cheapo poundland epoxy, it never seems to go off fully whenever I have used it. I might go with something like this which is a polyester resin - fairly cheap and designed for securing fixings. In the reviews there is a bloke who reported good success securing metal studs into wood.

The stress forces on the stud when it is screwed in will presumably be trying to pull the stud out of the holes you have made in the leg.
The more rough that you can make the inside of the hole in the plywood the better as it will allow for more mechanical pull-out resistance once the epoxy has gone off.

 

[robgul]

I don't think the threaded insert idea would be stable enough as they're only gripping a very short part of the stud on a pretty long (71cm) leg - and the table top is plywood 160 x 90cm (18mm with 100mm "rails" laminated all round underneath to give the appearance of 36mm plywood edge. (There's a post about Stretek ply that describes what I'm doing)

I have had some success with other projects using these Insert Nuts Type D M6 x 13mm 50 Pack - Screwfix which are more aggressive in terms of gripping wood (you wind them in with an Allen key - Amazon sell them as M10 about 25mm long)

The resin you suggest looks like the stuff to use - it's in my Screwfix basket. Thanks.

For interest I'm using these X-TREME Table Leg Mount | New Product - BPFonline Blog to fit the legs to the underside of the table . . . the wedge mechanism pulls the stud/leg up to the plate and ensures correct positioning of the leg (i.e. square to the table top)

 

[ChaiLatte]

Two of these. Trim off the excess:

https://www.toolstation.com/fischer-sanitary-fixing-kit/p86297

 

[profchris]

Surprisingly, just screwing the threaded rod into the wood holds remarkably well.

I'd guess a 9mm hole, lock two nuts together on the threads and then use those to screw it in, backing off from time to time - it cuts its own thread as it goes. But definitely find an offcut and try it first, in case your laminated legs decide to split.

Once threaded in, i'd remove, apply epoxy, and screw in again.

 

[robgul]

Surprisingly, just screwing the threaded rod into the wood holds remarkably well.

I'd guess a 9mm hole, lock two nuts together on the threads and then use those to screw it in, backing off from time to time - it cuts its own thread as it goes. But definitely find an offcut and try it first, in case your laminated legs decide to split.

Once threaded in, i'd remove, apply epoxy, and screw in again.

As it's plywood laminated together to I'd be drilling into vertical layers and be concerned about spliting, or failing with any flexing. I have just screwed 12mm studding into some hardwood with results that worked. The current project being a pretty heavy table needs stability!

 

[dizjasta]

Another option?

 

[robgul]

Another option?View attachment 166527

It's half in my mind to use them as well as the resin/glue - the one slight concern is that they may split the laminated plywood - and I have to drill out a slightly larger hole for the first n?mm to accommodate the insert, with the rest of the dept of the hole (total in leg will be about 100mm)

 

[Housey210]

I need to fix some short (125mm) lengths of studding into some table legs made from laminated plywood (72mm square) - the studs will protrude about 25mm and screw into plates fixed to the underside of the table - see pic of legs with studs loose in the holes. The bottom of the legs will have threaded inserts and feet in TRHC of pic.

View attachment 166520

Some sort of resin/glue is the obvious - but what is the best sort? The stress on the studs will be minimal. First thought was just the 2-part epoxy in the little dual-cylinder trigger packs from the likes of Poundland . . squirting both parts in the hole, stir with a skewer and stuff the stud in! Or is there a better material ?

I did consider threaded inserts for the tops of the legs but I don't think they would be stable enough.

M10 x 100mm Wood To Metal Furniture Dowels With T25 Torx Drive BZP​

https://www.tcfixings.co.uk/product...urniture-dowels-with-t25-torx-drive-bzp/15862

 

[clogs]

either drill out a slightly larger hole say ,5mm and use industrial anchor resin or as said before drill and make the studding cut it's own thread.....
I have used that idea a fair bit with no real probs....
BUT
u need to find the correct size drill as in tapping metal and modify the first 6 threads to make cut like a tap.....

PS, anchor resin is what hold industrial buildigs and machines down.....
if fact my 2 poster car ramp is held down this way.....only thing is the resin sets in just a few mins.....so u need to be ready....

 

[ChaiLatte]

...concerned about spliting

Whatever you do in the centre of the leg, clamp up the leg tightly with two opposing pieces of timber in both directions. That will prevent splitting when doing whatever you do, and stop the material moving away from the hole-forming device, ensuring the material is cut and removed rather than just displaced.

 

[robgul]

Whatever you do in the centre of the leg, clamp up the leg tightly with two opposing pieces of timber in both directions. That will prevent splitting when doing whatever you do, and stop the material moving away from the hole-forming device, ensuring the material is cut and removed rather than just displaced.

The legs have already been drilled with 10mm holes for the studding - see pic. I made a jig that clamped around the leg and them clambed a "mini-drill press" on the top to get the hole absolutely vertical. I had expereimented with drilling a sample leg section for the "screw in bolt!" idea but even with clamps and a pilot hole the ply "end-grain" distorted.

I think I have the way forward- drill a short hole in the existing to enable M10 nut inserts, then epoxy and screw the studs through the nuts and to the depth of the hole. Belt & braces!

 

[Jameshow]

Can you not get the thread insert that has a flat plate across the face and corner spikes that go in the wood? I'll have a gander for them....

These....
https://www.toolstation.com/pronged...&ranSiteID=pfxNKSnglIM-uDB1Nn4PSg4XYrGp0SFHBg

 

[Samkilby]

Yeah use resin.
Particularly don’t use the tee nut above as that won’t work at all, it is intended to be fixed the other side (in this application fixed to the bottom of the foot, with the threaded rod then having to extend through the whole leg.) it would just pull out as you tightened whatever on top, or even if you weren’t tightening anything on there would be nothing pulling it’s teeth into the timber.
Have a look at west systems. We use that at work. Don’t use araldite or similar if you can avoid it. Make sure you have some digital scales for weighing it out, and mix it for about 2 minutes. If you leave it for a long time in the same pot it gets hot (very hot) so suggest having several clean takeaway trays to decant to upon finishing mixing.

I would also in this context probably make 4 little guides or jigs to guide the rod both vertically, and centred on the leg as it sets. I guess something the same section as the leg, with something to locate it over the leg and a fairly tight hole that slips over the o/d of the thread. Or a birds mouth block (which will at least show it vertical and plane.) It will probably take 12-24hrs for the resin to go off properly.
You want to cover everything that you don’t want bonded with shiny parcel tape.

In future as suggested above I might consider “metal threaded dowel” or “metal dowel to coach screw” but hey ho. If you drill the pilot hole at the exact shank thickness of whatever you are screwing in it would help prevent deforming, as only the thread is then finding a home.. you could even wind it in a bit, then all the way out, wind it in a bit further, then all the way out etc to clear any material the thread has cut away. I would also likely drill pilot 10mm over length in this instance.

If you are affixing it to a ply or similar table top, I would likely soft pencil the top on the bolts, gently sit the top in position, then give it a heavy whack with a mallet above each leg to transfer the markings, effectively scribing it. You could cut some temporary “rails” for the legs to help with laying it out and clamp them in position. Similarly you could do the same with some blocks of timber to line up the overhang of the top. Or do the same with the whole thing upside down..
then if they are through holes, I.e. you intend to put a nut on the other side, I would likely drill a clearance hole, a mm or so larger than the o/d of the thread.

 

[robgul]

Yeah use resin.
Particularly don’t use the tee nut above as that won’t work at all, it is intended to be fixed the other side (in this application fixed to the bottom of the foot, with the threaded rod then having to extend through the whole leg.) it would just pull out as you tightened whatever on top, or even if you weren’t tightening anything on there would be nothing pulling it’s teeth into the timber.
Have a look at west systems. We use that at work. Don’t use araldite or similar if you can avoid it. Make sure you have some digital scales for weighing it out, and mix it for about 2 minutes. If you leave it for a long time in the same pot it gets hot (very hot) so suggest having several clean takeaway trays to decant to upon finishing mixing.

I would also in this context probably make 4 little guides or jigs to guide the rod both vertically, and centred on the leg as it sets. I guess something the same section as the leg, with something to locate it over the leg and a fairly tight hole that slips over the o/d of the thread. Or a birds mouth block (which will at least show it vertical and plane.) It will probably take 12-24hrs for the resin to go off properly.
You want to cover everything that you don’t want bonded with shiny parcel tape.

In future as suggested above I might consider “metal threaded dowel” or “metal dowel to coach screw” but hey ho. If you drill the pilot hole at the exact shank thickness of whatever you are screwing in it would help prevent deforming, as only the thread is then finding a home.. you could even wind it in a bit, then all the way out, wind it in a bit further, then all the way out etc to clear any material the thread has cut away. I would also likely drill pilot 10mm over length in this instance.

If you are affixing it to a ply or similar table top, I would likely soft pencil the top on the bolts, gently sit the top in position, then give it a heavy whack with a mallet above each leg to transfer the markings, effectively scribing it. You could cut some temporary “rails” for the legs to help with laying it out and clamp them in position. Similarly you could do the same with some blocks of timber to line up the overhang of the top. Or do the same with the whole thing upside down..
then if they are through holes, I.e. you intend to put a nut on the other side, I would likely drill a clearance hole, a mm or so larger than the o/d of the thread.

Yep the "spike nuts" wouldn't work as the would/could pul out of the plywood "end grain" - although I am using them for the adjustable feet which are a) to level the table as it straddles two surface finishes, and b) to keep the end of the plywood legs off the floor in case of any water/mopping etc drawing into the wood.

The legs are being fixed to the table top using some clever plates with a wedge mechanism that pulls the studding into the fixing - see link up-thread in the 3rd post. I shall be fitting them with the top upside down on trestles as there is a shallow aperture to be routed out for the wedge.

 

[Jameshow]

Yep the "spike nuts" wouldn't work as the would/could pul out of the plywood "end grain" - although I am using them for the adjustable feet which are a) to level the table as it straddles two surface finishes, and b) to keep the end of the plywood legs off the floor in case of any water/mopping etc drawing into the wood.

The legs are being fixed to the table top using some clever plates with a wedge mechanism that pulls the studding into the fixing - see link up-thread in the 3rd post. I shall be fitting them with the top upside down on trestles as there is a shallow aperture to be routed out for the wedge.

I was thinking of using the in addition to the epoxy. Knock them in and pour glue down the holes.

I wouldn't have a problem with aridite or any other quality epoxy brand like gorrilla glue etc. Poundland probably isn't the best place though!

 

[robgul]

I was thinking of using the in addition to the epoxy. Knock them in and pour glue down the holes.

I wouldn't have a problem with aridite or any other quality epoxy brand like gorrilla glue etc. Poundland probably isn't the best place though!

I've just ordered some of the heavy duty screw in things that work with an Allen key - with them and epoxy down the holes that should work. I'm going to use the resin that works in a caulking gun as it has a long thin nozzle to pass through the threaded insert - just then need to be quick with screwing the studs in!

 

[Agent_zed]

If you really dont want it to ever come out you could drill a 3 or 4 mm hole in through the side of the wood and the stud and then knock in a metal rod (nail shank) of the same size. Capped with a piece of dowel you'd barely be able to see it once all sanded flat. If it was 1.5 inches down it would also be hidden by the table top.

 

[throbscottle]

If you can get them big enough, why not use barrel nuts? The only real disadvantage is the hole you'd have in one side of the leg, but you can hide that.

 

[robgul]

Thanks for all the suggestions - I have now decided what to do . . . but am waiting on the spangly fixing plates which are on order from the UK agent of a Danish manufacturer. If I remember I'll post some snaps of WIP when I get to assemble it all as it does seem a nifty solution.