Wood splitting

[Kev grant]

Hi good evening to everyone, I'm in need of some serious help and would be so gratefull if someone on here could maybe answer a few of my questions. This is my first time I've ever posted so please excuse if I mess it up lol. To give you a brief explanation of the situation I'm in, i sarted my own small buisness in April making red pine toy boxes , we sold a fair amount over Xmas but all the boxes I have done are either totally warping to the point it's almost round lol and the others are splitting wide open down the middle front and or back, I use gorilla glue when gluing and clamping, and really just don't know what's going wrong. Any help would be great , I'll try attach a pic to try give u an idea of what I meen. Sorry for the huge message, cheers again (hammer)

 

[Jacob]

Wood not dry.
If you are buying typical redwood it needs something like 6 months at normal room temperatures before it is stable. It also need to be near finished size (thickness and width) plus about 6mm before you start drying it.
If you are trying to reduce thick timber to size it may need 6 months after you saw it, even if the thick stuff has already been drying.
In other words buy your materials a year in advance - or buy guaranteed kiln dried to 8% ish, but I doubt you could get redwood that dry. But you certainly could get hardwoods.

But the good news is you have been selling them so it's worth getting your act together!

PS if you are buying PAR (stuff already planed to size) you are on a loser - it's for joinery only and will distort all over the place given a chance. You have to be able to plane up and thickness your own dry stock

 

[RobinBHM]

Hi Kev, congratulations for starting a business in woodworking and sorry to hear youve had a set back.

Some more info is needed to identify the cause:

timber type, source and section use. (I know you mention pine, but that could be spruce or redwood in diff grades)

design -if you could put on pic would help hugely -although you need 3 posts first, so respond a couple more times.

Regards Robin

 

[CHJ]

Obvious answer as already mentioned is that the wood you are using is not dry enough (seasoned) and is splitting or warping as it dries out.

For positioning in a modern centrally heated home the wood needs to be 8-10% moisture content, especially if the items are likely to be positioned near a radiator or exposed to direct sunlight.

 

[beech1948]

The other thought is that your supplier may be at fault. IF you asked for kiln dried timber ( probably at or around 8%) and did not get it then the supplier is at fault. Time to go back and have a strong conversation with them.

If you bought the timber from B&Q for example then its worth atry but they are very obscure about levels of moiture in their timber.

Hope that helps.

In future maybe consider using ply and a painted finish. See here:-

https://www.youtube.com/watch?v=j6rebBggLvY

Alan

 

[Kev grant]

Trying to work out how to reply lol

 

[Kev grant]

Nailed it lol, thanks for getting back to me so quickly. And thanks robin it's great but a headache at the mo.
I use 19/95mm redwood for the side panels and trim it with 12/45mm redwood top and bottom. I glue and clamp then router the joins. Some have split open by almost an inch, I'll sent pics ASAP
Cheers again everyone

 

[Kev grant]

I get my wood from a local building suppliers as to the eye it seems to be the best about where I am.
I thought it was prob the wood not being dry but didn't think for 1 min it would take 6 months. I had it stacked for a week in my workshop at 10 degrees and thought it would do the trick!!! How wrong I was !!!

 

[Random Orbital Bob]

Just as an aide memoir....the rule of thumb for naturally (air drying) wood is 1 year per inch of thickness plus a year! Obviously it's not an exact science since it depends on many variables including temperature, timber density etc.....but you get the picture.....it takes a hell of a long time naturally. Kiln drying of course aims to improve that time considerably. If kiln drying is to be successful it has to remove an awful lot of moisture right down to the levels other posters have mentioned ie below 10%. Here's the problem, because different suppliers advertise "kiln dried" wood with different standards, you need to be able to focus down and research one that guarantees the moisture content. Longer term, it will be cheaper to manage your own stock. Short term, you need a reputable supply source.

Even if the wood is at 8% MC and then you cut it to your box dimensions, the very act of cutting wood with all its myriad different grain variations can and often does release tensions which cause the warping and bowing. You'd be surprised at how strong those forces can be too. So that's why it's best to a) keep it dry to below 10% MC and b) to mill your own stock well in advance and then final finish it just before you use so any stresses that will cause twist etc have already been exposed in advance.

Now you know why man made boards like Ply and mdf get used so much....cos they're stable!

But persevere...and keep posting

 

[Kev grant]

Thanks guys all your help is much appreciated, I've scrolled the internet for a week now trying to get answers. I'm glad I tried you guys tonight, I'm gonna upload a few pics for you to have a look at to make it all a little clearer. I hav done 36 of these boxes for Xmas and I'm sure everyone will come back I'll put up the pics I have back from some customers. Thanks again in advance (hammer)

 

[Kev grant]

Hope these pics help folkes, these are just a few I hav been sent and are in no way the worst, 1 box in particular has 10mm gaps front and back and another is almost round :lol:

 

[undergroundhunter]

Is that a T&G joint or just a plain edge joint?

Matt

 

[PAC1]

As others have said the wood was not dry enough. However even with properly kiln dried wood you need to design so that the wood can move as it will and nothing will stop it. A large panel of pine glued up from several pieces will split unless it can move freely. The alternative is to make the boxes from MDF. It is stable and paints well once you learn the right technique. The downside is it is heavy and horrible to work with due to the dust.
Having said that good luck with the business.

 

[oakfield]

From the pictures, it looks like you've used tongue and groove, and glued all the joints - this effectivly creates a large solid panel and this is where the problem is.

The point of tongue and groove is to NOT glue them together so they can all expand and contract individually.
If you have 10 boards and all of them shrink by 1mm it will not be noticeable, if they are glued together, the whole panel will then shrink 10mm - this will be noticeable!!

 

[Random Orbital Bob]

Right...I see your problem now. I hadn't imagined the boxes were quite as large as that for some reason. I would call those "chests" I think.

I can see 3 simple alternatives with varied costs/effort:

1) Use kiln dried tongue and groove pine and avoid any glue in the T&G joints....glue (or even just mechanical fixings) only the frame elements
2) Use beadboard (google search it) which is a very useful sheet material (stable) with the vertical "beads" pre engineered which give the effect of T&G....its actually just one sheet so easy to work with.
3) Use a cheaper sheet good (like regular mdf) and route the grooves yourself before painting.

Your problems look two fold superficially.....the dryness of the wood and the method of edge jointing ie the design of the joinery. The good news is it's not difficult to fix with the correct materials. The even better news is you've clearly got a rather good little business model and I suspect, production challenges are easier to fix than revenue demand challenges

Edit: Mine and Oakfields crossed in the ether

 

[Mr T]

You can get MDF sheets with beads and v grooves routed already this would save time and you would not have to allow for movement.

Chris

 

[Kev grant]

Hi everyone and good aftrnoon, thanks for all your in put. The boards I use set just square edge and I routrer them with a v groove once clamped to give them a T&G effect, I thought if I glued and clamped all the boards then glued and nailed the 12/45 trim top and bottom this would hold it all together, how stupid was aye. I originally made it out of MDF for pictures but when we started selling them we made them out off red pine as after a bit of research that was what everyone said the were wanting, the problem I have is that on my website and Facebook etc we are selling them as solid pine toy boxes so don't want to start using ply or MDF but think its gonna have to be my only option. I was thinking if I bought pre-fab T&G boards without gluing them up would this give me the same look but also allow the wood to move freely???? Not sure if that all make sense guys, thanks again in advance

 

[Random Orbital Bob]

Yes it does (make sense). One of the previous posters mentioned it but let me reiterate......the whole purpose of tongued and grooved boards is to allow the wood to shrink across its grain (the width of the board) without showing any gaps. Of course the vertical v groove effect is nice aesthetically too but its joinery design is to avoid EXACTLY what you're experiencing.

So what you need to do is use dry (MC circa 8%) pre T&G pine boards (or get a T&G router bit and do it yourself on a router table) and only apply glue to the frame elements and NOT the boards where they slip into one another. That may just work. The "proper" way to do it really is to build a square/rectangular frame with mortise and tenon'd joints where the members meet (styles and rails) and rout a housing top and bottom into which you fit the t&g pine boards with NO GLUE at all on either the top or bottom or vertical joint of the pine boards. The pine just "floats" in the routed channel top and bottom and any movement is accommodated by the gaps either side of the panel. Movement in wood is vastly mostly across its grain so you needn't worry so much about the tops and bottoms being flush. The sides need a few mm of movement potential.

Let me gig out a picky of a planter I made recently to illustrate the design I mean. Hang on.

 

[Random Orbital Bob]

This should show the principle of joinery behind a wooden frame that houses a floating wooden tongue and groove panel. For the sake of cost and tool avoidance, you could probably join the corners with dowels or just mechanical fixings to avoid the hassle/time of mortise and tenon. But the principle of the floating panel is what I'm driving at here. That's the solution in first principles, the frame joinery could even be done with metal L brackets!! Or use the bead board/mdf and change the promise on your website

Hope this helps anyway.

 

[Random Orbital Bob]

Incidentally, all the wood in that was rescued from a pub skip. The frame was the legs of one of those classic pub benches and the side panels were pallet wood that I T&G'd with a router table. (Only 1/2" thick)