Started cutting cross halvig joints and have some M & T joits
to do soon.
What type of fit is ideal?

eg
slip fit - slips into place without pressure.

nice fit 1 - pushed together firmly by hand

interference fit 2 - requires pushing together with the tap with a mallet

interference fit 3 - requires pushing together with a few belts with a
mallet

Incidentally I am using red hardwood for the verticals and mahogany for the
horizontal members
for an external door frame with side and toplights.
It may be a bad mixture but I'm not going to change it now.

Thanks.

Arthur

Arthur2 wrote:
Started cutting cross halvig joints and have some M & T joits
to do soon.
What type of fit is ideal?

eg
slip fit - slips into place without pressure.

nice fit 1 - pushed together firmly by hand

interference fit 2 - requires pushing together with the tap with a
mallet
interference fit 3 - requires pushing together with a few belts with a
mallet

I'd go for Nice fit 1.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

"Arthur2" wrote in message
...
Started cutting cross halvig joints and have some M & T joits
to do soon.
What type of fit is ideal?

eg
slip fit - slips into place without pressure.

nice fit 1 - pushed together firmly by hand

Somewhere between the two is the usual fit for a mortice and tenon joint -
push together with light resistance. You may need to assemble and dismantle
the frame a few times, to get all the joints right, so you don't want
anything more difficult to assemble, but too loose will weaken the joint. If
you need extra strength, as you will for a door, make it a haunched through
wedged mortice and tenon.

The first drawing here shows a through wedged joint - note the taper on the
outside of the mortice. You tap the glue-covered wedges in as part of the
final assembly, when you are also gluing the joints. The third drawing shows
a haunched tenon. The haunch supports the joint to the edge of the wood and
gives extra area for glue..

http://en.wikipedia.org/wiki/Mortise_and_tenon

Colin Bignell

Depends on the size of the timbers. Significant persuasion is ok if
you're jointing oak beams. Generally you want to stop short of any
danger of the joint bulging or splitting, and particularly for m&t
joints that will be clamped, glued and back-wedged, a smooth sliding
fit is fine.