is 18mm thick MDF ok for 3/4" T-Moulding?

[jimmy2x2x]

Im looking around for a local MDF supplier and the closest they seem to stock 3/4" is 18mm.

According to online conversions, 3/4" is actually 19.05mm

Can you actually buy 3/4" MDF

[The Lumberjackass]

hi jimmy,

here's the deal.
the mdf sheet when you buy it, will be 18mm , but the t-moulding will actually be the full 19mm wide.
so thats 1mm wider than the sheet. why you ask ?

well, for starters , alot of wood products that are on sale today are nowhere near the proper spec listed by the manufacturer.
a good example is 2" x 4" lumber, which is used for houses . the final dimensions are closer to 1.5" x 3 1/2" . so technically ,
calling it 2 x 4 is well off the mark. sometimes the reason given , is that the wood IS actually cut to spec at source, but during the treatment prior to sale,
the heat and different factors can sometimes change the dimensions of the wood. so , as for mdf , the same can be said .
in ireland, where i live, if you leave mdf out on a cold day , it'll widen to the 19mm easily, sometimes more . it all depends on moisture in the air.
other factors are the different measurement methods, i.e metric and imperial , so sometimes they just round off at the nearest measurement for comprimise.

but as for your question, 19mm mdf can be bought , it just depends where you go. but i'd stick with 18mm as the t-moulding
needs to be a bit wider so it'll cover the edge perfectly. trust me on this, stick with 18mm , as if you make a small mistake with the accuracy
of the slot cutter ( i.e - if you miss the dead center of the panel ), at least you have 0.5 of a mm to cover the small inaccuracy .

my cab is 18mm mdf , the t-moulding is 19mm . most , to all cabs are the same , unless the moulding is " blended in " with a router to match the edge.

[jimmy2x2x]

Thanks for the comprehensive answer

18mm it is

[Roo]

I just wanted to add that the t-molding samples I just received from t-molding.com are a slightly bigger than advertised.  I'm measuring almost 13/16" or right on 20mm.  And that's before you install it.  the molding has a slight curve, so depending on how deep you set into the slot, it will expand even more.  Like Lumber said, the molding is slightly larger by design, to cover slots that are not exactly centered.

Somewhere here I saw a good tutorial on using a chisel to trim t-molding.  I'll try to find it.  I wouldn't use a router, since the molding is round, you wouldn't have a good base to sit your router on.

Edit:  here ya go:
http://forum.arcadecontrols.com/index.php?topic=86699.0

[The Lumberjackass]

I just wanted to add that the t-molding samples I just received from t-molding.com are a slightly bigger than advertised.  I'm measuring almost 13/16" or right on 20mm.  And that's before you install it.  the molding has a slight curve, so depending on how deep you set into the slot, it will expand even more.  Like Lumber said, the molding is slightly larger by design, to cover slots that are not exactly centered.

Somewhere here I saw a good tutorial on using a chisel to trim t-molding.  I'll try to find it.  I wouldn't use a router, since the molding is round, you wouldn't have a good base to sit your router on.

yeah, sorry i didnt explain that one better. im used to woodworking , so i have all the tools needed to trim down an edge. most pro's use a router ,
but its a small router and designed specifically for edge banding or triming the likes of t-moulding. so , ya sorry bout that, using a full size router you'd
be asking for trouble, lol.

you can also use an edge banding tool to trim. here is one, i also have it : http://www.axminster.co.uk/jet-edge-banding-trimmer-prod576751/ , but i dont reccomend you trim any t-moulding on an arcade cabinet. even if the t-moulding is sticking out 1mm each side. if you trim it , you run the risk of not being able to re-fit it perfectly, should you ever feel the need to remove it for maintenence etc etc.

check this vid of mine out :

you'll see me using t-moulding on a wardrobe , yes, a wardrobe i trim it with the trimmer too :p