Rounding corners, any suggestions?

[Lord Kitchener]

I like to round the corners of my doors (which are 19m thick) with about 1.5mm to 2mm radius. At the moment I do this by hand, but would like to find a more consistent method. I round the edges of the doors easily enough with a hand-held trimmer and suitable bearing guided cutter, but corners are a lot trickier. Any suggestions as to better method, and one that could be used by a less skilled person would be welcome. Consistency is what I am looking for here, speed is less important.

 

[Cheshirechappie]

100 grit sandpaper and a sanding block.

 

[Stormer1940]

Clamp a wider block to the flat of the door to create a larger area for the router/trimmer base... The block would obviously need to flush with edges of door...

 

[adidat]

make a wooden profile and then glue sandpaper inside it, this would give you accuracy.

adidat

 

[AndyT]

A small radius out-cannel gouge would make a paring cut of consistent shape.

 

[Lord Kitchener]

100 grit sandpaper and a sanding block.

To get the consistency I mentioned earlier, that would require even more skill than is needed at the moment.

Clamp a wider block to the flat of the door to create a larger area for the router/trimmer base... The block would obviously need to flush with edges of door...

There might be something in that but it would need a block either side of the door… and would take quite a long time to do if there were several door each door requiring 4 clamp-ups...

make a wooden profile and then glue sandpaper inside it, this would give you accuracy.

The problem here would be the radius, to bend sandpaper to 1.5mm radius would be tricky and it would have to be prevented from touching the door anywhere else than where the radius is required. Plus it would need to be moved in a dead straight line, tricky to do by hand.

A small radius out-cannel gouge would make a paring cut of consistent shape.

Another possibility, but I haven’t yet found a gouge in the required 1.5mm or 1/16” radius, plus it would still need a good deal of skill to get a perpendicular cut.

 

[Stormer1940]

Why would you need a block on both sides? You would only need one on the lead out side and this could be easily cramped on with a one handed cramp in a matter of second. Having a block on the leadout side will also help with breakout.

If you made the block eg 40mm, with the thickness of the door you are giving the base of the chosen trimmer 59mm to rest on. You may want to put some pads on the cramps jaws to protect the work piece.

 

[petermillard]

As the doors are only 19mm, then a template for the radius clamped to the top face of the door and a bearing-guided template/profile cutter would do this, surely?

 

[Jacob]

What's wrong with a bit of sand paper? You just pull it over the corner using both hands like drying your back with a towel.
A few practice goes and every one will be perfect.

 

[Stormer1940]

As the doors are only 19mm, then a template for the radius clamped to the top face of the door and a bearing-guided template/profile cutter would do this, surely?

I think we are thinking along the same lines.

 

[joez71]

How about something like this:

http://www.finewoodworking.com/pages/w00113.asp

Although I think it still might be tricky on such a small radius...

joez71

 

[AndyT]

If you are talking about a whole batch of cupboard doors, removed from the cupboards, you could clamp them all together in a stack and use the same roundover router cutter as you used for the long edges. Add a sacrificial block to the top and bottom of the stack.

 

[Cheshirechappie]

How much skill do you need to use sandpaper and a sanding block? You'd need far more skill (and safety knowledge and PPE) to use a router!

 

[Jacob]

You don't even need a block if you use fabric backed paper (from a sander etc) and pull it over the corners. Very controllable.

 

[Lord Kitchener]

Yetty has sent me a pm with a good idea, and I will almost certainly adopt it. I'll give him a chance to post it here, if he chooses not to I'll draw it up in sketchup and post it.

 

[Yetty]

I keep a 1/4" router [near] permanently fitted with roundover cutter in a small homemade table.
When a round-over is needed, I just lift this table onto the bench, ready to work straightaway.
Here's a pic of the table

First cuts are the edges shown rounded in His Lordship’s diagram. The work is held vertical while cutting, using the 90 deg end of the sacrificial piece.
Sorry don’t have exact photo to hand but I bet you get it...

I more than likely pinched the idea from somewhere near the internet. It works well for repetitive jobs and is consistent. The 12-edges are rounded in less than a minute, all nice and even!