Open (?) mount

[pramsay13]

I had to reframe an old mount that got damaged in a fire, and I was to copy the existing mount exactly.
It's like a v-groove, but 10mm wide so that it shows the bottom mount. I've already done it and it has turned out fine, but I'm just checking I did it right, and if there is a better / easier way.
I cut smaller aperture 115mm from edge, flipped mountboard around and cut it 95mm from edge. This gave me a 20mm rectangle of mountboard. I then turned it back over and cut it 85mm from edge. I put on bottom mount, stuck the smallest internal piece back on and cut it 125mm from edge. Then I stuck 20mm rectangular bit in the right place. This gave me 85mm of upper mount, 10mm showing through to bottom mount, 20mm of upper mount, and 10mm bottom mount.
Despite my long winded description, it sounds easier on here than it was in practice, and there was a lot of measuring before cutting.
Any comments?

[birdman]

It's hard to say, hard to read too. Do you have a photo that might make it a little easier to understand please?

[pramsay13]

I thought that might be the response once I read through it.
I'll post a photo later.

[prospero]

I do them like this......

First, if you are bottom-weighting the margin, cut the margins as if all the margins were the same as the bottom and trim the top/side down when you finish.

Second, cut a corner sample first as the widths can go haywire because the of the bevels and they don't always come out how you designed them. Remember the settings in case you get it right first time.

OK. Cut the top mount window to the outside of the 'groove'. (First make a pencil line across the back so you can keep the dropout in the same orientation). Tack the bottom board to the top in the same way as doing a double mount. Cut the bottom board window.
Take the dropout and shave the width of the 'groove' off each side, face up in the cutter. Flip over and cut the window. Careful here not to ding the nice crisp corners.
Put strips of d/s tape behind the inner bit. On one side, use three bits. Only peel the middle bit which only needs to be 1" or so long. Peel the ends of the rest of the strips, just enough to fold the release paper into the window area. Leave the middles stuck. This will prevent the tape grabbing when you try to align it. Use the shaved off portions of the groove as a gauge to get the spacing exact. When it's in the right place, press down gently on the peeled bit of tape to tack it. This will hold it, but allow you to lift it again if it has wriggled out of place. Check the spacing again before pulling the protruding ends of the release papers and smoothing down in turn.

Easy init?

** this is the second time I have typed this. If you read the first version, please ignore it as I was thinking of fillets.

** Use proper double-stick tape to attach the inner bit. DON'T use AT tape. Rub it down well an it won't shift. You can add a dot of PVA for extra security, but in this application it's very easy to get it where you don't want it.

[stcstc]

or just type some numbers in a cmc

[prospero]

Does the CMC stick it all together for ya?

[IFGL]

I'm pulling the manual cutter out of the cellar in January, looking forward to using it again,

[pramsay13]

Sorry just realised I've returned this without taking any photographs so my meaning will forever remain a mystery

[misterdiy]

Since the CMC will cut it in one go you would use the drop out to place the inner mount correctly. It's dead easy and quick with a CMC.

[easypopsgcf]

I think it's known as a double inset bevel mount, easy enough

[Roboframer]

It's like a v-groove, but 10mm wide so that it shows the bottom mount

That, at least on the Valiani software, is called an "open 'V' groove" - which seems like a fairly self-explanatory description.

Pretty naff though; never even looked at it; if I ever had to do one and if there were no fancy bits, just a square/rectangle.... or even naffer, a circle/oval, I'd probably just plot it without the facility the software provides.

[Sam Cook]

Hi, think you all have this covered by now but just thought I would post a quick picture in case anyone reading it was still confused!
Wizard call it an Open V Groove as well (as opposed to the Closed V Groove were the 2 bevels are touching, which is what most people would just call a v groove). Personally I think they can look pretty effective, and can look nice done with a double mount using the same board colour.

[Roboframer]

I rest my case

[Sam Cook]

Now, now, each to their own and all that ..........