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Box construction

PostPosted: 01 Dec 2016, 21:51
by Wizard9999
Hi all, question on technique.

I am making a box at the moment as a Christmas present. I have cut a dado in each side to receive the base and have made a base by edge jointing two boards and then running it through the thicknesser to get it to the required thickness. When I cut the base to size I have allowed a little room for expansion of the base across the grain.

My question is this. When I assemble the box should I simply leave the base free floating or should I glue it in the centre of the two sides with end grain. I am instinctively drawn towards glueing it and think that should be fine as it will not stop the panel moving across the grain. I presume there is much less scope for movement along the grain. If it is material to the advice the base panel is about 220mm square and 7mm thick.

Many thanks in advance,
Terry.

Re: Box construction

PostPosted: 01 Dec 2016, 22:55
by TrimTheKing
Yep I would do that Terry. Couple of small dabs of glue, no longer than about 10mm.

Cheers
Mark

Re: Box construction

PostPosted: 01 Dec 2016, 22:58
by Wizard9999
Thanks Mark. I can crack on tomorrow now. Realise I should not be asking such things at this stage, but kind of making it up as I go along with insufficient planning.


Terry.

Re: Box construction

PostPosted: 01 Dec 2016, 23:01
by TrimTheKing
Not at all mate, the only daft question is the unasked one when you aren't sure!

Cheers
Mark

Re: Box construction

PostPosted: 02 Dec 2016, 00:45
by Rod
Wood shrinks less along the length so glue one side IE not End grain side.

Rod

Re: Box construction

PostPosted: 02 Dec 2016, 00:54
by TrimTheKing
Rod wrote:Wood shrinks less along the length so glue one side IE not End grain side.

Rod


Not sure what you're saying here Rod. He should be glueing the centre of the end grain ends of the base (in theory the short ends on a rectangular box) to allow the timber to expand and contract across the width on either side of the centre...

Unless you are suggesting glue only one 'long' side and allow it to shrink and grow all the way across?

I would go for my suggestion personally (as I would ;)) as it means less overall movement for each side of the glue joint.

Cheers
Mark

Re: Box construction

PostPosted: 02 Dec 2016, 00:55
by TrimTheKing
And I mean just a dab in the centre of that endgrain, not all the way along.

Mark

Re: Box construction

PostPosted: 02 Dec 2016, 04:10
by Rod
I was taught as your 2nd para Mark
But your suggestion would work too.

Rod

Re: Box construction

PostPosted: 02 Dec 2016, 09:37
by Wizard9999
I can see how both methods would work. My only concern with glueing one long side is that this means all of the expansion gap in the dado would be on one side, so all things being equal that would mean that gap would be twice as deep as if the gap were split between the two sides. As my base and dados are already cut I am worried that this would mean a risk the base could contract so far it comes out of the dado.

If I were at an earlier stage and using the glue one long side technique would the right approach be to cut asymmetric dados? So a shallower one on the side the base will be glued and a deeper one on the opposite side, thus meaning a bigger expansion gap can be left. Does that make sense? Any merit in this or am I over thinking it?

Terry.

Re: Box construction

PostPosted: 02 Dec 2016, 09:55
by 9fingers
I agree with your concerns terry. A dab in the centre of the end grain sides seems the best way to me.

Bob

Re: Box construction

PostPosted: 02 Dec 2016, 10:17
by Tusses
I agree with the theory ... but it depends how big the box is.

most small boxes I see are fully glued.

I made a frame and panel box about 20 yrs ago .. fully glued .. and just big enough for 1 bag of sugar, for an idea of size.
Made from pine, panels are apprx3mm thick.
I had concerns of movement .. but it's been fine, and still used as the sugar box in the kitchen today :-)

I made a tea caddy at the same time .. sort of coopered, in the shape of a kettle .. so segmented barrel.
The base is fully glued to the "barrel", and had also been fine. it's approx 5" diameter

Re: Box construction

PostPosted: 02 Dec 2016, 10:48
by meccarroll
For solid wood construction (frame and panels) it is not common practice to glue the panels in place.

For a panel of 220 square it's not necessary to glue the panel at all. I have made numerous pine cabinets with solid pine door panels of around 400mm square and not glued any of them in situ, I have also used larger end panels unglued and all have been fine :) .

The panels were set in a 1/2" groove with a total of 1/8" clearance for expansion (1/16" each edge). Just condition the wood to the end climate before assembly to minimise movement ;) .

If you are set on gluing the panel, then I'd do it as Mark stated, it won't do any harm and would centre any movement to equal sides of the panel.

Rod is correct is saying that in most cases wood shrinks less along the grain than the width. But you would not glue along the grain on one edge in practice because, if shrinkage does occur, all the shrinkage would have to be taken up in (the unfixed side) the groove on the other side (possibly forming a visible gap).

Having said all of the above for the size panel you are working with you could probably do it either way without much detrimental effect from shrinkage provided you condition the wood first :? :eusa-doh:

Mark

Re: Box construction

PostPosted: 02 Dec 2016, 10:57
by Tusses
meccarroll wrote:For solid wood construction (frame and panels) it is not common practice to glue the panels in place.
Mark


Egg Zackery !

Nine was an experiment . as there is no top rail.
Maybe having it filled with sugar, stabilises the moisture content ???

anyhoo .. it's still not split in 20 yrs :-)

think about all the really REALLY !! cheap tools (or whatever sets) you get , likely from china (or screwfix etc.) lots come in fully glued boxes. most are ply , but some are solidwood.

Obviously, if fully varnished / sealed .. they "shouldn't" move

Re: Box construction

PostPosted: 02 Dec 2016, 11:14
by Pinch
Terry, where is the WIP report chap? ;)

Movement is always going to be perpendicular to the direction of grain and depending on timber species, moisture content etc will vary in the performance of movement - albeit not that much for a base of a small box. This can be over analysed. In the past, I've glued panels in fully, dry fitted them, dabs of glue down the sides with the grain or just the corners etc etc and I've never had any issues. Most finishing applications will also adhere to all the joints as well and a bit of movement will slightly open the junctions where the base meets the box.

Interestingly, I watched the Guy Martin programme where he got a little bit involved with rebuilding a MK1 Spitfire - great programme loved it. He was shown how to make some large rivet bolts (not sure of their correct name) which connect the wings to the fuselage. When he finished one of them to the correct tight fit size, he was chatting to the camera holding the rivet. The warmth of his hand expanded the rivet enough so it wouldn't actually fit into the hole. The rivet was then left to contract back to it's correct fitting size.

Also (yes I know, I'm rambling on now), Guy kept saying this funny two word term which I couldn't make sense of at first and then the penny dropped. Guy's term for 'bosom buddy' is 'tit mate'. :lol: :lol: Made I laff it did :lol: :lol:

Re: Box construction

PostPosted: 02 Dec 2016, 11:25
by meccarroll
Tusses wrote:
meccarroll wrote:For solid wood construction (frame and panels) it is not common practice to glue the panels in place.
Mark


Egg Zackery !

Nine was an experiment . as there is no top rail.
Maybe having it filled with sugar, stabilises the moisture content ???

anyhoo .. it's still not split in 20 yrs :-)

think about all the really REALLY !! cheap tools (or whatever sets) you get , likely from china (or screwfix etc.) lots come in fully glued boxes. most are ply , but some are solidwood.

Obviously, if fully varnished / sealed .. they "shouldn't" move


Ok, except China and Screwfix............. "SPOOK"......... :lol:

EDIT TO THIS:.....We must have been typing at the same time Rich, as I only saw your reference (Post) as I pressed the submit button and thought....Oh well I'm sure he will be alright with! :D :?

LOL

Re: Box construction

PostPosted: 02 Dec 2016, 11:29
by Pinch
:lol: :lol:

You'll all be doing it tomorrow! :lol:

Re: Box construction

PostPosted: 02 Dec 2016, 11:41
by DaveL
The other way to stop the panel moving is to use little rubber balls, iirc they used to be sold as space balls. I think you could make some using a bead of silicon, left to set and then cut into short lengths.

Re: Box construction

PostPosted: 02 Dec 2016, 12:07
by Tusses
meccarroll wrote:
"SPOOK"[/i]

LOL


:lol:

see .. everyone is doing it tomorra !

Re: Box construction

PostPosted: 02 Dec 2016, 12:42
by Wizard9999
Well it's in clamps now, with a dab of glue in the centre of the end grain. I suspect you are right in that the movement over such a small piece would not be consequential anyway. But as much as anything as a novice I am keen to know which ways are right and wrong and most importantly why, all part of my education.

Pinch, no WIP I'm afraid, as much as anything because being on the first step of the woodworking ladder it takes all my concentration to get something vaguely reasonable, so no spare brain capacity to think about pictures. If the end result is not ridiculously embarrassing I'll post a picture when it is finished. So if you never see a picture best not to ask :lol:

Any recommendations for small butt hinges for the lid? I have looked at Brusso but are there others I should consider?

Terry.

Re: Box construction

PostPosted: 02 Dec 2016, 12:58
by Tusses
how small is it ?

if it's small enough would folded leather be ok for hinges ? ads a nice touch when done properly :-)

Re: Box construction

PostPosted: 02 Dec 2016, 13:55
by Wizard9999
Tusses wrote:how small is it ?

if it's small enough would folded leather be ok for hinges ? ads a nice touch when done properly :-)


It's about 220mm square by about 100mm high. It's the doing it properly that worries me :lol:

Terry.

Re: Box construction

PostPosted: 02 Dec 2016, 14:18
by Tusses
not quite tiny then ... a lot of "craft" hinges are just pinned in .. using a punch to just push the pins(nails) in place

Re: Box construction

PostPosted: 02 Dec 2016, 14:29
by 9fingers
Terry, one tip that is no help to you now now but maybe for future boxes is to choose and buy your hinges first..

Then you can choose the thickness of the timber to suit the hinge. either rebate for the full thickness of the timber to match the hinge or make the timber a good few mm thicker than the hinge leaf width.
What you want to avoid is cutting rebates for the hinges just leaving a couple of mm strip intact. Quite likely to end in tears. DAMHIKT!

Another reason is that IME vendors are poor at giving comprehensive dimensions of their hinges. I was trying to match a cock bead size from router cutter range to match the knuckle dimension of the hinge.

Bob

Re: Box construction

PostPosted: 02 Dec 2016, 14:30
by RogerS
DaveL wrote:The other way to stop the panel moving is to use little rubber balls, iirc they used to be sold as space balls. I think you could make some using a bead of silicon, left to set and then cut into short lengths.


Correct. Terry, I have some you can have if you like. They entered the country a while back via Bob :eusa-clap:

I am in the 'Don't glue' camp. The downside is that it might rattle but once you've stuffed it full of stuff, that 'problem' will go away !

Re: Box construction

PostPosted: 02 Dec 2016, 14:30
by RogerS
Note to self. Read the whole thread before commenting :oops: