Morso UNDERPINNER (UPM) advice

[cleaver]

Hi All,

I’m finally getting some framing done in the new workshop.

Managed to change the Morso blades without slicing any fingers, so all good there (touchwood the accuracy of cuts seems good with new blades).

Sticking point is the Morso Underpinner – and I wondered if we had any UPM users around?

Basically, anything except dead flat moulding is a problem. On non-flat mouldings it wants to prise the mitres apart (and won’t even stack wedges on such mouldings). It doesn’t help that only the V-shaped pressure pad came with the machine .

Anyway, I wondered if anyone has any tips and advice on this issue?

The machine itself seems to have plenty of welly, and it feels something like as smooth and powerful as a compressor-driven machine (I had a tiny bit experience with a compressor-driven pinner).

Any advice would be great.

Ta

[Justintime]

Try this
https://www.underpinner-spares.co.uk/co ... ngular-pad
Cut off what you dont need with a blade and superglue it to what you have.
Worked a treat.
Spreads the load!

[prospero]

Just about to say what Justintime said.

Spread that load.

On some mouldings that have a high back/front, the top pressure is always on the high point. But the nail
insertion point may be offset from this high point by a big margin. Thus when the hammer comes up it lifts
the two pieces and makes a bad join.
You need to keep the top pressure point right over the nail insertion point. This might seem impossible, but with the aid of
some little 'helpers' you can work round this. The simplest one is and L made from square timber and faced with cork or
polyurethane. Placed on the lowest point of the profile it allows you to exert the top pressure in the right place.

If you are pinning a particularly awkward shape regularly the elegant solution is to make a reversed chevron from a scrap
piece of the same moulding. Placed face-down over the corner it effectively makes a complex shape into a flat moulding.

[cleaver]

Thanks so much, chaps.

Am I also going wrong (compounding the issue, if you'll forgive the pun) in not moving the hammer for the 2nd wedge position? I'm currently bringing the hammer down on the highest part of the moulding (usually the back), and inserting all wedges with the hammer in that same position.

Getting better results by putting the back wedge in 1st, then the one on the rebate side.

I really want to make it work with this machine: if you haven't used one, it's just what you'd expect from Morso....rock-solid engineering, and the hydraulic action is very smooth and powerful. But someone else told me it doesn't like non-flat mouldings.......so I am worried.

I've just ordered that Veritas clamp, which will be useful whatever happens, as I might try gluing up, then pinning when dry. But that can't be a long-term fix, I know.

BTW, I've seen the other hammers on Danslist, but can't work out how one buys from them. Anyone ever bought from them?

Thanks for the link, JT.....I'll grab one of those.

[cleaver]

Sorry, when I say 'hammer' in my last post, I mean the clamp that holds the moulding from the top.

[Justintime]

I think it depends on the width of the moulding, if you need to move the head for the second position or not. If the head is no where near above the second position, then yes you need to ensure that the head is applying pressure above where the wedge is being pushed up. Also the head/clamp needs to be just above the moulding in order to provide sufficient clamping pressure. If the clamp is set too high, there will not be enough pressure from above. Does that make sense?
If you're using a glue like Titebond 3 remember that you have a working time of about 5 minutes.
Any Morso supplier like Lion's Wessex etc should be able to supply you with Danlist parts, if they are still available new, otherwise Mark at Underpinnerspares.co.uk or Peter at Framers Equipment might be able to help with used parts.
Now I have glued that soft white part onto my Cassese L shaped head, I rarely use the circular bung option.
It's trial and error to get the positioning and pressure right. As long as you're using the basic techniques, the rest is tweaking.
If I've got spare, I often test first on an offcut.

[cleaver]

Thanks, Justin - you're a top lad

Tiling the living room fireplaces today, but will get that pad on order pronto.