Guys

Making a dolls house for the girls xmas. Putting about 10 windows in
it..so made up a nice template from a 9mm offcut of mdf - basically 8
windows about 1 inch square in a row of 4 x 2.

Bought a template bit ( with a bearing at the top of the cutter) and
off I went with my router. I am cutting through 9mm mdf with the bit...

First window went fine..Then noticed as I cut more that the bearing
appeared to be reshaping the mdf template...Suffice to say, after 1
usage some of the template was wonky and cutting curvy window shapes...

Essentially the bearing was routing the edge of the template...I
presume this is the soft MDF..any clues as to what wood to use to avoid
this...Would ply work before I buy a bloody big sheet..

Cheers

Ged

wrote:
Guys

Making a dolls house for the girls xmas. Putting about 10 windows in
it..so made up a nice template from a 9mm offcut of mdf - basically 8
windows about 1 inch square in a row of 4 x 2.

Bought a template bit ( with a bearing at the top of the cutter) and
off I went with my router. I am cutting through 9mm mdf with the bit...

First window went fine..Then noticed as I cut more that the bearing
appeared to be reshaping the mdf template...Suffice to say, after 1
usage some of the template was wonky and cutting curvy window shapes...

Essentially the bearing was routing the edge of the template...I
presume this is the soft MDF..any clues as to what wood to use to avoid
this...Would ply work before I buy a bloody big sheet..

MDF is soft but you must be pressing really hard to notice a problem
after such little usage. You could try plastic electrical tape f it's a
one off or recut the edges and put some formica or something equally
hard in as a lining. A strip of tin or some such or even lollypop or
chopsticks. Whatever is hard and handy will fit the bill.

You might be able to drill out most of the orifices with an auger bit
to ease the load. I don't know if if that helps?

PS

You might prefer to get a router guide that follows a template laid
over the work:
http://www.diydata.com/tool/router/guide.jpg

The follower will need to run in a hole marginally larger than the one
the cutter is making -by the difference in the size of the follower and
the diameter of the bit.

E.g.:

If the bit is 1/8" smaller than the guide, the template has to be 2 x
1/8" larger or 1/8" larger for each edge cut. The followers come in as
many varieties of sizes as the bits do. Just make sure the bit isn't
too large for the one you buy.

The follower looks a perfect solution. Thanks for your advice..

Ged

wrote:

The follower looks a perfect solution. Thanks for your advice..

Take the router with you or make a note of the make and model and
remember the cutter size too. Some makes will need different followers
to others. Bloody silly really, like battery chargers and other
manufacturing hazards.

You could screw a thin mdf plate to the sole of the router if you can't
find one to fit and screw it to that.

wrote:
Guys

Making a dolls house for the girls xmas. Putting about 10 windows in
it..so made up a nice template from a 9mm offcut of mdf - basically 8
windows about 1 inch square in a row of 4 x 2.

Bought a template bit ( with a bearing at the top of the cutter) and
off I went with my router. I am cutting through 9mm mdf with the bit...

First window went fine..Then noticed as I cut more that the bearing
appeared to be reshaping the mdf template...Suffice to say, after 1
usage some of the template was wonky and cutting curvy window shapes...

Essentially the bearing was routing the edge of the template...I
presume this is the soft MDF..any clues as to what wood to use to avoid
this...Would ply work before I buy a bloody big sheet..

MDF works.
Are you sure your bearing is working?
If its not rotating freely you will wear or possibly burn the MDF.

As others have said a template collar is probably better but it will leave a
bit more waste in the corners.
You probably want rounded corners on a dolls house if its for kids as they
are easier to clean.

wrote:
Guys


First window went fine..Then noticed as I cut more that the bearing
appeared to be reshaping the mdf template...Suffice to say, after 1
usage some of the template was wonky and cutting curvy window
shapes...

Essentially the bearing was routing the edge of the template...I
presume this is the soft MDF..any clues as to what wood to use to
avoid this...Would ply work before I buy a bloody big sheet..

Either bearing not working properly (common on cheap bits, or too much
pressure. Coat the edge of the template with PVA glue to harden it up, that
helps.


--
Dave
The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257

On 6 Nov 2006 14:46:07 -0800, wrote:

Guys

Making a dolls house for the girls xmas. Putting about 10 windows in
it..so made up a nice template from a 9mm offcut of mdf - basically 8
windows about 1 inch square in a row of 4 x 2.

Bought a template bit ( with a bearing at the top of the cutter) and
off I went with my router. I am cutting through 9mm mdf with the bit...

First window went fine..Then noticed as I cut more that the bearing
appeared to be reshaping the mdf template...Suffice to say, after 1
usage some of the template was wonky and cutting curvy window shapes...

Essentially the bearing was routing the edge of the template...I
presume this is the soft MDF..any clues as to what wood to use to avoid
this...Would ply work before I buy a bloody big sheet..

With moderate pressure against the guide the outer part of the bearing
should not rotate.

It sounds like the bearing is sticking, try a drop of oil on it and
then rout some scrap to get rid of the excess.

Also consider fitting some small aluminium strip or angle to the edge
of the template to protect it.

cheers,
Pete.


Cheers

Ged