Thickness Planing MDF

T

The Cobbler

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I need some strips of 1/2" MDF to replicate some trim that I made a bunch of years ago.
I have 5/8 but it will show ( to me anyway)
I know carbide blades are recommended for planers. My power plane has carbide but my thickness planer is just regular HSS. It could use a change of blades ( which I have) . How bad would the MDF be on the old blades... will I get the job done ? about 40' of 5/8X4" 5/8 planed to 1/2"
 
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N

Nobody-named-Olli

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With @loganb on this. MDF is nasty, even if it’s just the ‘backing’ of some man made material … MDF is the one material that I will only lightly sand in preparation to any sort of coating myself. All other steps cutting/routing i.e. are done by the supplier. I refuse to expose myself to that these days.

Kind regards,
Olli
 
P

PCustoms

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Typically once you break the "skin" on MDF it gets very fuzzy...

I suppose you could put that on the back, but be aware.

Depending on how wide id consider re-sawing before I put it through the planner
 
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RTM

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I would not do that to my power planer, a hand plane, or my lungs. Like said above, I think the finish will get gross.
 
M

Miss the Pontiacs

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Never done it, I don’t even like X cutting mdf on my slider and I have a pretty good dust recovery. I have to rip a 10’ piece of mdf down the center. But waiting to move the table saw outside and hoping for a bit of a wind as well. Our 6” snow dump stopped me from doing it today.
If you take an 1/8” off the back would loosing the relief cut be a deterrent?
Remember to take some pics for this thread.
 
S

strutaeng

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Dallas, TX
Does it have to be mdf?

I did a bunch of casings using preprimed, finger-jointed 1x3 from the home center. Initially I used it full thickness but found the 3/4" thickness was too much, especially meeting the baseboards which were like 9/16".

For the next project, which was rather larger, i ran them through my Dewalt lunchbox thickness planer and thicknessed them to 5/8" or so.
 
M

manwithtools

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For future reference I'll add that I recently did this with my Dewalt 735 planer with helical carbide cutting head and good dust collection and it worked beautifully. To the OP as long as you are due for a change of knives, I'd give it a go on your existing ones with a small piece and see what the results are. You do need good dust collection for this operation.
 
J

Jayman17

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I think it would be easier resawing that on a table saw if you have one. You would have to flip it over side for side to make the 4 5/8 width.
 
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