How deep should the housing joint (?) be for a drawer base

[el_Pedr0]

Hi all,

I'm designing some drawers for my wardrobe - about 800mm x 500mm x 140mm deep. The sides and back will be made from 15mm thick solid walnut, front from 19mm walnut, and the base from 6mm veneered mdf. How deep should I router the channel in the sides, front and back to slide the drawer base in?

Thanks

 

[harryc]

6mm is enough.

 

[Cabinetman]

It’s quite subjective, but I would say 6 or 7mm and I would make the groove in the front the same as the sides, if it was me I would have the back shorter so that you can slide the base in afterwards and screw up Into the back.
Traditionally the grain in the base would have gone front to back and in a drawer that wide you would have a muntin, ( a thicker piece of wood to help support the base).
It’s a groove by the way, a housing normally goes across the grain, as if you were supporting/ sliding a shelf in for instance. Ian

 

[Sgian Dubh]

Traditionally the grain in the base would have gone front to back and in a drawer that wide you would have a muntin ...

I suspect a wee brain fart. I think you probably meant to say the long grain normally goes from one side to the opposite side. A typo maybe? Slainte.

 

[Cabinetman]

Did I really write that? Doh! Yes obviously t' other way

 

[el_Pedr0]

Further questions:

1) Do I need to leave some extra space in the groove to allow for the mdf drawer bottom to expand with humidity/temp? If so, how much extra do I need to allow in total in each direction?

2) does a muntin deserve a particular joint like a mortise and tenon, or would it be sufficient to simply stick it on. (That feels stupid even as I write it - I suspect I know the answer).

3) can the muntin be mdf or ought it to be a piece of solid wood?

 

[Cabinetman]

1, no extra space needed as ply movement is virtually nonexistent
2,I think you can get away with it under the plywood, just a tongue into the drawer front and screwed up into the drawer back, in olden times the drawer bottom was in two halves which slotted into grooves in the sides of the muntin.
3, a piece of solid wood really, anything will do. Unless you want to make a feature? Of it, as in the old days, then it will show in the bottom of the drawer. Ian

 

[el_Pedr0]

Thanks @Cabinetman ,though the base is 6mm mdf not ply.

 

[recipio]

Is that 140 mm high rather than deep ? If not you will end up with wide and shallow drawers which will rack as you use them. To answer the question. about 5 mm is fine for a groove in 15 mm timber. Of course if you let the mdf into the back it will all have to be assembled in one go. Otherwise you could shorten the width of the back so that the base is simply screwed into it. Many will cut the base extra long so that it hits the back of the wardrobe and acts as a stop.
Ply would be more durable than mdf.
( I'm assuming you are not going to use metal runners ) Lastly its a bit pricey using walnut for the drawer sides - a cheaper wood or even baltic ply would give a bit of contrast with the front but that's entirely down to you.

 

[el_Pedr0]

Sorry - yes 140mm high.

I don't think I mind too much about assembly all in one go (he says never having made a drawer before). I was kinda thinking that the drawer bottom would actually help keep everything square during glue up. I'm going to be using Blum movento runners, so they'll do the stopping for me.

Primary reason for choice of mdf over ply is that mdf is cheaper and I'm already using 6mm mdf for the cabinet backs. Therefore it will be quite a saving not having to purchase a whole sheet of a different material...

...However, this is meant to look, feel and perform as high end as I can reasonably make it (hence why I'm going to first price it up with real walnut drawer sides). And so if an extra 100 or 200 quid on walnut veneered ply drawer bottoms is clearly the right decision, then that's what I should do.

Are ply bottoms clearly the right way to go?

 

[Cabinetman]

Oh yes MDF, well it’s veneered which stiffens it up no end so it will be fine in drawer bottoms, particularly if you fit a muntin as discussed, I’ve never glued drawer bases in so can’t comment but I can’t see why it wouldn’t work and you could do away with the muntin probably then.

 

[recipio]

The standard depth for hanging clothes in a wardrobe is 600 mm so if 500 mm is the depth it will be a bit tight. If the drawers are 800 wide you will definitely need a solid wood muntin for support and veneered mdf would be fine as the base. The muntin can be let into the underside of the front and back or if you really want high end construction you might consider using a profile and scribe router bit on the router table ( if you have one ) which will machine all the joints of a base frame and the groove for the mdf - a bit like making a panel door.

 

[el_Pedr0]

Oh - bottoms aren't glued?

In the meantime - I've spoken to the hardwood store, and actually if I buy a sheet of veneer, a sheet of heat activated glue and some wpb ply it might not be so much more expensive (though I've still got to run the numbers).

@recipio
The hanging part of the wardrobe is 520mm deep. But it works out OK because there's no back (so it saves a bit of space that would otherwise be a void), but mostly because there are no doors. It looks fine though - I've done one to these dimensions before and the clothes don't jutt out.

I've just today bought a good second hand router (a massive upgrade from my wobbly lidl thing). Planning on doing dovetailed joints for some of the drawers and have a Leigh jig to help - because the last dovetail I did was 30 years ago so out of practice to say the least. Don't have a router table at the mo...

 

[el_Pedr0]

@recipio Re: profile and scribe for the muntin. Are you suggesting the the muntin doesn't just sit below, but that the bottom is split into two parts, sitting in a groove either side of the muntin? Like the 'in the old days' construction that @Cabinetman refers to in his point 3 above?

 

[recipio]

@recipio Re: profile and scribe for the muntin. Are you suggesting the the muntin doesn't just sit below, but that the bottom is split into two parts, sitting in a groove either side of the muntin? Like the 'in the old days' construction that @Cabinetman refers to in his point 3 above?

Yes. A muntin should be about 18 mm thick to offer real support. 6mm grooves in the sides take the mdf so its exposed on the upper side of the base. Putting it under the base means it will be thin - more like 8 mm. The mdf should be glued in. This was the traditional way to make a chest of drawers as of course the drawers run on the side of the frame. If you are using metal runners you could use an easier construction - using a Leigh jig will add another learning curve so stand back and mull over it. You know that if you use metal runners you will need a false front to hide the gap between the drawer sides and the side panel. ? Just sayin'

 

[el_Pedr0]

False front hopefully isn't necessary in this case because I've got 'fascias' (not sure what to call them) on the sides of the cabinet. So I can make the drawer sides flush with the edge of the draw fronts, and the gap due to the runner is hidden by the fascia. - Just realised I haven't posted a picture in this thread so here it is:

Leigh jig learning curve - I'm up for that (he says naiively).

 

[el_Pedr0]

If you are using metal runners you could use an easier construction

Please could you elaborate a bit. Some of the complexity I'm doing conciously because of a benefit (e.g. dovetails = strength and beauty). But there's probably a lot that I'm not aware of that's unnecesarily complex.

 

[recipio]

Please could you elaborate a bit. Some of the complexity I'm doing conciously because of a benefit (e.g. dovetails = strength and beauty). But there's probably a lot that I'm not aware of that's unnecesarily complex.

With respect, you are probably making the job too complex. Dovetails are nice but a bit over the top for wardrobes with utilitarian metal runners. ( I had a Leigh Jig but gave up on it as it made clunky industrial style dovetails ).
There will be a 12 mm gap between the face frame and the drawer side and that needs to be hidden. Most people use an overlaid drawer front as you can adjust it when the drawer is in place . I'm pretty sure that you can do the same with insert drawer fronts with careful fitting but haven't done so personally.
Fitting side metal runners can be tricky and you could use undermounted runners instead. The problem is really that the costs add up and you might even need the specialised drilling jigs for the Blum range that professional fitters use.
If you are going to commit £1000 + to the project I would do your research thoroughly and maybe make a mock up of a drawer fitting. Accuracy is everything with these projects.

 

[el_Pedr0]

Thanks recipio. Appreciate the advice and sanity check.

I'll be using the undermounted blum movento runners. This means that the beauty of the drawers wont be spoilt by the utilitarian metal runners. The blum runners also give a degree of adjustment themselves, giving me a mm or two's grace. I recognise that this is an expensive route, and yes, my ballpark estimate was around £1000+. It might sound a bit mad, but I'm confident it's in keeping with the spec of the house and is a sound investment.

Actually very keen to finish the sketchup model which will then give me quite a precise cutting list that I can get costed up.

Agree with the need for accuracy. I'm definitely going pretty far on the planning stage. and I'll make sure I do some mocks of the critical joints and components.

 

[Sgian Dubh]

Sketch for a typical drawer muntin, this being of the quadrant pattern that matches quadrant style drawer slips rather than the flush pattern that matches flush slips. Slainte.