Accurate router templates in MDF with hand tools?

[DigitalM]

Hybrid hand tool / power tool question, apologies if it looks like it's not in the right forum, I think it probably is.

So I've got to make a bunch of router templates for a quick project, using the old guide bush and calculating the offset etc. So I'm on top of all of that. But I've got to know them up with hand tools as I can't get over to the workshop until the weekend and want to max my time there.

So I'm looking for tips on how to cut 6mm MDF (or is there something better) with handtools. Yeah, I know about drilling in the corners and then using a coping saw and all that malarkey, it's the next bit - cleaning up those rough cutouts into sharp, vertical, straight lines, and smooth curves.

I've thought about files, sandpaper, chisels.

Anyway, for the sake of argument, let's imagine two templates.

1. A rectangle.
2. A letter D shape but not a circular curve, something a little more bezier.

And the scenario is cutouts for electronics, a bit like what is done for guitar controls, which are then covered with a nice plastic plate with the electronics recessed below.

 

[MikeG.]

No plane or spokeshave?

I would cut a line with a straight edge and a knife, pare aware on the waste side of that then cut some more with the knife, and repeat until you get to full depth. That's the straight stuff dealt with. For the curves, I would lay out the geometry on cardboard then cut that out. Use this to transfer the shape to the MDF, where you mark it with a pencil. Then cut outside this line with something crude (coping saw, maybe). I would then lay the MDF flat on the bench and slice away manually with a sharp chisel until you were back to the line. Sandpaper would round the edge profile over, so I'd try to avoid its use. Finish with a blade.

 

[DigitalM]

Will have to try just getting straight lines to depth progressively with a knife. I hadn't imagined that would work in MDF (grabbing some tomorrow or I would try it tonight).

Your curve strategy is pretty much the same as mine, but the knife idea for the straight lines sounds like it could be bang on quite easily.

Thanks.

 

[DigitalM]

Well I found a bit of MDF in the attic and conducted some tests.

The knife cuts well enough but it's not terribly easy to stick to vertical and takes a bit of cleaning up - no doubt it can be improved with practice and care (neither of which I had on a Monday night - out of alcohol, two hours of book keeping earlier in the evening, no motorbike racing on the telly).

Now here's a shocker. I have a Record No 730 buried in among my GumTree tool haul - tried that and it worked really well - totally vertical cut, easy to clear the waste during the process by means of a stanley knife. A bit of a pain to align and I didn't have any clamps handy, just ran it against a reasonably straight off cut - but such a clean and vertical cut. I think with a little patience/experimentation it would be great for MDF templates. I'm not saying it's the best way to proceed, I was just messing about with it and found the results quite surprising, I had sharpened the blade quite carefully a while back, mind. Well, it's a bizarre idea (or is it?) but it does work, maybe that's actually what they're for. I thought it was going to be a total 'harrumph' but it was something of a 'hurrah'.

There we go. Let the Record No 730 hate mail begin!

 

[sunnybob]

I use ply for all my templates. Easy to cut with normal handsaw and smooth with sandpaper. lasts forever and doesnt crumble with use. lighter than the same thickness mdf and comes in any thickness from 3 to 12 mm

 

[Paddy Roxburgh]

A sharp block plane will cut the mdf no problem. With a bit of practice the convex curve can also be cut with the block plane. Sore the line with a knife and then carefully plane to your lines If you don'y have one a bench plane would also work. Paddy

 

[DigitalM]

Thanks for the input guys, I've got three days to mess about with it all!