The Framers Forum

Ok,

So this is a bit embarrassing but I'm not sure how to get really tight miters with the under pinner and I'm hoping someone can offer some advice.

I've got a basic underpinner - the CS79 but every time I try to pin my small oak mouldings, it seems to not pull together the mitres.

I've tried both soft and hardwood Vnails and neither seem to produce the results I get by using a stanley band clamp. With the clamp, there is Zero gap. It takes some aligning in the vertical plan but I've had a bit of practice at this now and they always look pretty good. But it's time consuming and I only have so many clamps...

Here's the really embarrassing bit - I then take the frames to the underpinner to put in a nail once the glue is dry just as a back up in case the frame is ever dropped or knocked, so that it would at least not fall into pieces, even if the mitres did break. Is this totally unnecessary? I know how strong wood glue is and that in normal use conditions, the nail offers no additional strength to the frame, I've only ever done it for the reason mentioned above.

I cut my mitres on the Morso but I've never been shown how to make frames, or underpin and I feel like I might be missing a trick here.

One thing I've wondered while using the underpinner is how much force should I use to press the mouldings together i.e manually closing the mitre gap up before pressing the pedal? I've never been shown how to use an underpinner so I've maybe got my technique wrong? Can technique go far wrong with an underpinner?

Any suggestions of methods that I can have a go at would be kindly received, tested and reported back on.


Tom

Hi Tom,

Have you checked that the receiver block, which dispenses the wedges is level with the sliding top plate? There is not any positive stop which ensures this is automatically locked in position at the correct level. You can check this is level with the sliping top plate with a straight edse.

Hi Mark,

I Have not checked that.

I bought the underpinner from a framer who was selling some old equipment that had been in use so I'd assumed it was ready to go. I will definitely give it a check though. Thanks for that.