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  1. 1. Do you currently own a cutting machine?

    • Yes
    • No, but I want to in the next 12 months
    • No, I have no plans to buy one
    • I'm undecided at the moment


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Andy, it's interesting the sheet is so out, I wonder if I should have done more lighter cuts? It sounds like Jim has an answer. Would the stretching be consistent enough to allow the cutting diagram to take it into account, or would the change have to be measured each time? I'm really going to have to try to find a copy of the David Jenkinson book, they are like hen's teeth! Maybe with the surge of popularity of the cutter and everyone going off to build coaches now's the time for a reprint. ;)

 

Hi Allan, thanks for dropping by. If the plastic stretched then it'll be interesting to see his we get around that - frequent lighter cuts maybe. It's interesting that you use Sure Cuts A Lot (SCAL) for the cutting, did you consider the CutWizard or Silhouette Connect, or did SCAL just do what you needed? It's out of my price range, but the Silver Bullet looks interesting.

 

I agree with Allan, some of the other people on the thread will tell you that on my Wainfleet thread I was concerned that I was "cheating" but now I see a cutter as no different to a lathe, or 3D printing, they are a (very interesting) means to an end that, once mastered will allow people to build things more quickly, and to venture off and try things they wouldn't necessarily tried with a scalpel and a ruler.

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My new toy was delivered to my brother this morning, so I can't wait 'til christmas to have a play.

 

Can anyone please point me in the direction of a supplier of the CB 09 blade that I have seen mentioned in this thread.

 

Cheers SS

 

edit for spelling. I might get the hang of making posts using a tab one day.

Edited by Siberian Snooper
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Hi SS, I just went onto eBay and found a Chinese supplier that will deliver to Canada. You need to make sure you get the CB09, not the CB15. Some sellers sell the blades separately, I specifically looked for one that sold 60 degree blades. Great it's turned up!

 

I've put a quick poll up to see approximately how many machines are out there and are likely to be before asking about a special interests section.

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Andy,

 

You might have to watch out for the styrene sheet stretching under the cutting action of the blade.  This is a known problem when cutting the panelling layer out by hand.   David Jenkinson shows his method of getting round the problem in his book and I do remember a demonstrator at the London Easter show way back in the 60s advising builders to cut the panelling layers first then cut the main sides to match the size of the panelling. :-)    You could check that just by putting a ruler on the panelling layers after cutting to see if there is any stretch.

 

Jim.

 

 

Not sure whether or not this will help out, but I found that when cutting out anything intricate like Georgian windows for example, it was best to cut within a very generous margin of material which would allow the finest of work to be cut out withoud warping, buckling or stetching and then cut to size after. If you've time, check out the rose window in my cathedral, all cut out of postcard quality card in one piece.

 

This is probably totaly irelevent to the way things are cut out by a machine but it was just a thought and I hoped it may be of use.

 

Cheers.

Allan.

 

Edited for atrocious spelling !

Edited by allan downes
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I think you're right Allan, a generous margin would definitely work. On a smaller scale, it helped me with the beading on my shorter coach. I had quite a margin around it. Andy G, maybe I should have included a larger margin around yours and not been quite so tight on the use of plastic. :-/

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Hi Allan

 

Ha, an ironing press! I was given a hot press by a photographer friend a couple of years ago, but I've never had the courage to turn it on. Maybe if I do some stuff in card (which is my preferred building building material is you see what I mean) I could give it a go; outside to start off with. I can get Gorilla wood glue here in Canada.

 

I think it was when I was producing some gates that you mentioned that latex spray glue was too flexible. You were definitely right there as you could bend them quite a way without them creasing, though they did spring back. It didn't matter when I was putting the gates together, but I definitely wouldn't use it on a building that didn't have some sort of stiff core. Your mini paint roller sounds like an interesting way to glue evenly. Do you get any rippling  or is the glue laid down really sparingly?

 

cheers

 

Jason

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Sash Windows

A quick one this time to show how the cutter can do the sash windows. Obviously these could be cut by hand, but imagine consistently cutting all of the windows for a mill or a Georgian mansion. Or even, dare I say, for a large cathedral!

 

A sash window or hung sash window is made of one or more movable panels or "sashes" that form a frame to hold panes of glass, which are often separated from other panes (or "lights") by narrow muntins.[1] Although any window with this style of glazing is technically "a sash", the term is used almost exclusively to refer to windows where the glazed panels are opened by sliding vertically, or horizontally in a style known as a "Yorkshire light", sliding sash or sash and case (so called because the weights are concealed in a box case). The oldest surviving examples of sash windows were installed in England in the 1670s, for example at Ham House.[2][3]

 

From Wikipedia

 

Creating the sash window effect manually needs a good eye and a steady hand as they tend to be comprised of numerous small panes of glass separated by narrow muntins. Cutters can cut down on the work needed to create one of these windows. You can cut styrene, card, paper or labels to produce sashes of various styles and sizes. The example here is a basic one with a rounded top created for the signal box at Wainfleet that was made from several layers of card glued together. In my case, the windows were actually cut in situ inside the walls instead of cut separately and glued as inserts.

 

For the windows I used the following card layers:

  1. The cutout in the wall
  2. Window frame (slightly smaller than the cutout)
  3. Upper panes
  4. Lower Panes
  5. “glass” – plastic sheet

The window frame was glued to the front of the wall, and the other pieces were glued to the back. In my case the card I used wasn’t very thick, so I put the “glass” behind the whole window, instead of using separate layers. You might want to create a gap where the top two panes are if you wish to glaze the windows on different layers (if you see what I mean)

 

The different layers were produced as follows:

 

post-14192-0-77489900-1386394857_thumb.jpg

The first image called full shows how all of the windows stack up, and below is the horrifically enlarged finished window itself - the glass was that dusty, honest! And yes, there should be a brick arch there...

 

post-14192-0-41453000-1367260291.jpg

 

post-14192-0-90088700-1386395594.jpg

 

As Allan was saying, a wide margin will help to stop the styrene from warping, so I haven't included the outside edge of the material that you would be cutting. I created my sash windows in card when I put together my signal box, and though my gluing was suspect, the windows themselves were cut square.

 

Of course, if you produced your windows in styrene, I’m sure a way could be found to make a positionable version. Now there would be a challenge - how about it in your next building Lee?

Edited by JCL
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Those signal box cut outs JCL - mighty impressive and as clean cut and as accurate as any kit I've ever seen - absolutely superb

 

Just one observation if I may.

 

The vertical bars on the sash window are too thick. One needs to consider that a glazing bar is about half an inch thick and in model terms represents little more than a hairline but of course there has to be a limit to dead scale.

 

Anyway JCL, please forgive me, but I've taken the liberty here to show you a coupla three signal boxes with  brass etched windows of such fine dimensions that I would be extremely hard pressed these days to equal by hand, if at all.

 

Cheers.

Allan.

 

post-18579-0-54517800-1386413111_thumb.jpgpost-18579-0-85860600-1386413180.jpgpost-18579-0-71970800-1386413229_thumb.jpg

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Thank you all for the info and experiments. About 18 months ago I exchanged messages with Allan when I was wondering about the Cameo and plastikard and was in touch with a firm that was developing blades. I didn't get any sort of helpful response. This thread has awakened my interest.

 

I do recall comments about the material stretching and it will be interesting what solutions emerge, especially to see whether it is even across the piece or not.

 

Am I right in understanding that the Portrait only differs from the Cameo in width of the cutting area and that in all other respects the capabilities and techniques are the same.

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Lessons can be learnt as much from the mistakes as the successes.

 

There is a feature of the Silhouette machines typically referred to as print and cut. What this means is that an image is first printed, together with registration marks, then loaded into the Silhouette and cut out.

 

I thought I would try an experiment with the sample coach section I featured previously, but this time printing the full livery to the material before cutting. The artwork was modified, still using Inkscape having imported the Studio registration markings. This was printed on Inkjet 200gsm matt paper:

post-3717-0-33654900-1386422383_thumb.jpg

 

This close up shows what has been included in the colour print:

post-3717-0-18270400-1386422438_thumb.jpg

 

The print was allowed to dry and then sprayed with UV protector. Print was then added to the Silhuoette cutting board, loaded in the machine and a cut using the new CB09 cutter performed.

 

Now when cutting from Inkscape the cutter goes through an initialisation process which looked as if it was searching for its registration marks. I hoped that on cutting it would find the registration marks and align the cuts to the printed image. Unfortunately not so I will need to try exporting into Studio and seeing if I can control it from there.

 

The cutter performed perfectly.

 

The problem was when I tried to remove the printed/cut image from the cutting matt, it tore to pieces:

post-3717-0-32786900-1386422776_thumb.jpg

 

Now I have read on many posting that the original "stick" on the cutting matt is too strong and needs reducing, so when I finally manage to clean it up I will attempt to do so and perhaps try again.

Edited by MikeTrice
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Chaps,

 

Have been following this with interest!

 

A couple of doubts are nagging at me and it relates to the sticky mat.  On the one hand, if the "stick" is too keen, we end up with the problem Mike had above.  On the other hand, if the stick is not keen enough, it seems that the material moves under the knife - there are a number of examples of coach panelling earlier in the thread where the thickness of the bars were inconsistent - a problem which (given that the machine is accurate) would seem to stem from such a cause.  I also noticed that there was a significant amount of burr round the cut edges.

 

Forgive me if I have missed the answer to this somewhere else in the thread, but since it is possible to get the machine to re-trace a cutting path acurately as many times as you like, what is the effect of cutting, say, 10 thou plasticard in, say three passes rather than one?  that would reduce the burr, minimise the chances of the blade displacing the material on a thin cut and reduce the need for a strong bond to the mat?

 

- again please tell me to look harder if the answer has already appeared!!

 

Cheers,

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is possible to get the machine to re-trace a cutting path acurately as many times as you like, what is the effect of cutting, say, 10 thou plasticard in, say three passes rather than one?  that would reduce the burr, minimise the chances of the blade displacing the material on a thin cut and reduce the need for a strong bond to the mat?

It is perfectly possible. When I cut my coach sample in plasticard I did two passes for the 10thou layer. Once a single cut has been performed, providing the job is not ejected from the machine, further cuts can be performed.

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Yes, the mat is too sticky to start off with. It's fine for styrene, but you can't easily pull the card off. Allan's palette knife is a method prescribed by the manufacturer, but I'm a bit tight, so I slip a Stanley knife style blade under the card at a shallow angle. An alternative could be to do what they do with sticky tape and dab a fleece or something onto the mat. If you don't go overboard, some fibres will stick to the mat, reducing its stickiness. My guess is that this is what happens naturally over time anyway as when you pull card off the mat some card fibres will be left on there.

 

Once the mat has settled down, it seems to be at the same level of stickiness for a long time, which meant that I didn't need to refurbish my mat for a full year - and that's including having a large and hairy dog in the house! Going back to my maintenance post, you would then use goo gone and respray with 3M repositional glue. I think that replacement mats are 12GBP each in case you would want to go that way.

 

With regards to the cutting, yes, you can recut the diagram any number of times and the knife will follow the same path. In the Silhouette Studio software you can cut once or twice. If I want to get on with something else, and I want to get the software to cut the plastic more than twice, what I've done in the past is:

  1. Save your work (Ctrl-S)
  2. Select all (Ctrl-A)
  3. Group (Ctrl-G)
  4. Copy and paste - this will paste the second copy at an offset
  5. Click on the align button to open the align window
  6. Align centre
  7. Align middle

The codes in brackets are the key presses you can do to run the actions, you can also click on toolbar buttons or menu options.

 

This will move the new copy so it is exactly above the original copy. When you come to print, it will then print the two copies twice, obviously making four passes while you get on with something else. Of course, you can always watch it working. :)

 

With regards to the coach cutout Howard, I'm not 100% sure what the difference in widths was, it was possibly a combination of draftsmanship (it was Andy G's first go at drawing it one up and only my second one, so we were both on a learning curve) and cutting. Experimentation is ongoing!

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Hi Allan - yep, you're right, the verticals are too thick - I did them when I first got the machine and, as with Mike, I was having problems lifting the sheet from the mat. I think that, now I've been experimenting, and I've had the mat longer, I can get them to be much finer. In .010" styrene I'm down to about 0.45mm, but I haven't been back to card yet to see how thin I can get it.

 

Mike, you beat me to it! One thing, how will you get around the white cut edges? I know I'm probably telling you how to suck eggs, but I bought a couple of Clever Models kits and I think they said to use a felt tip or watercolour pen on the back of the card and the ink from this should soak through the thickness. Those watercolour pens are expensive though!

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With regards to the coach cutout Howard, I'm not 100% sure what the difference in widths was, it was possibly a combination of draftsmanship (it was Andy G's first go at drawing it one up and only my second one, so we were both on a learning curve) and cutting. Experimentation is ongoing!

 

It was Andy Gs which I noticed (no criticism intended!) and it does not look like a drafting issue:-

 

post-11380-0-65594300-1386443197.jpg

 

- rather, I think I see the same effect I have experienced trying (not successfully!) to do it by hand - the blade drags the material from under the straight edge if you press too hard - hence the gentle curve in what ideally should be a straight line and a different radius in the bottom corner compared with the top..

 

In an instructional video on Youtube, I noticed that you can just get the machine to re-cut the same image any number of times if you don't eject the cutting mat: many light cuts ought to be better than one or two heavy ones - even if it is a machine wielding the knife!

 

Best wishes,

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One thing, how will you get around the white cut edges? I know I'm probably telling you how to suck eggs, but I bought a couple of Clever Models kits and I think they said to use a felt tip or watercolour pen on the back of the card and the ink from this should soak through the thickness. Those watercolour pens are expensive though!

I picked up a large set of 30 coloured fibre pens from a pound store in the UK. I plan to use the nearest colour and just run it around the cut edge.

 

Following on from my earlier post, I have (almost) got my cutting mat clean after a lot of scraping. I think the problem with the registration is I need to do everything from within Silhouette Studio. Have been watching a couple of youtube tutorials.

 

I am still having great problems trying to export from Inkscape to dxf, and yes the problems are with inkscape. Instead I should be able to simply export the coloured parts as a png file, import it into Studio then trace to get the cutting paths, so viable. Problem is my little Grandson is with us so I dare not get it all out to try it.

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Not only do I admire your expertise guys, I also admire your sense of humour - a great asset in my case when putting a Superquick kit together !

 

 I read tis thread with a mix of  ignorance and delight - the ignorance because I haven't got a clue as to what you're all talking about, and the delight at what you are all achieving - anyone know the co-ordinates of a moon shot, that could be interesting too !

 

Keep this thread going guys cos here lies the future of modelmaking !

 

Allan.

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Ok things seem to have moved on a bit from the top of the page, but I am going to put peoples faith back into the portrait (or Cameo in this instance)!

 

The registration issues I believe were actually a drawing issue (How I have no idea!), but when I drew registration checking lines all over the file (About 50 of the things!) I discovered that the windows on all but the top layer were all over the place (consistant with each layer, but not where they should have been. So I have ammended them to where they should be and done some other adjustments to.

 

Interestingly enough the 'movement' was all less than 1mm out, but enough to be noticable. I think we should check everything with multiple layers before we cut, with lines and maximum zoom. It sounds tediuos (and in practise it does take time) but I think it will pay off in the end.

 

Mind you, having said that the result from the trial side is no worse than some of the kits you can pick up!

 

Also some of the cut variations (Like the one that Jason picked out above) were again down to drawing not cutting, or down to the sticking down. The worst bit (which must have been down to the blade) is the top of the windows in the top layer, although I don't know why. Could be a dull blade wandering slightly, or the grain in the sheet. It didn't do it of the long cuts, which is strange.

 

But lets face it, this is top level pickiness, as I would be bl**dy amazed if I could ever achieve anything near as fine as this with a blade and a ruler. Nothing in life is perfect, and even machines have limitations, and we must be right on that edge asking for this level of fineness.

 

Will little things like this put me off. Hell no!

 

Andy

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Have been following the trials and tribulations with interest, and comparing these with my experience in hand cutting styrene and card. Have also been examining the true motion of the blade via loci diagrams through different angular movements -

 

In cutting styrene, pressure to hold the sheet firm is paramount because the surfaces on both sides do not resist movement whilst cutting, and therefore requires a sharp blade and a number of shallow passes. With card the amount of pressure required is not as great as the surfaces are not as smooth, however by the same token the drag on the blade is greater, and a number of passes is still required

 

Single deep cuts will depart from the true path due to movement of the media, and also in the case of hand cutting the straight edge or the uneven side pressure induced by the hand

 

Thick materials increase the possibility of drag and stretching, as the blade thickness forces the sides of the cut apart. Close parallel cuts in materials are more susceptible to movement of the material across the cutting mat, again as the blade thickness forces them aside

 

An increase in the number of lighter blade passes reduces the wear on the blade 

 

When the blade is being dragged round curves the side and forward drag/pressure will change due to variation in angular movement causing non-uniform curve paths

 

Speed and depth of cut should be kept to absolute minimum, especially when using a machine. By hand it is easier to control these if not the accuracy of the movement

 

Straight horizontal and vertical cuts are ok

 

Because the cutting edge of the blade is slightly offset to the centre of the blade holder, the path the blade takes around curves is not true, but follows a path outside the true path. The smaller the curve radius the greater the inaccuracy

 

I am not sure how and in what order the machine decides to make the cuts. Ideally for accuracy all horizontal cuts should be made first, then vertical cuts, followed by curves, and then repeating the same cuts. Even better would be to develop absolute registration and make successive cuts from both faces (mirror fashion obviously)  

 

Hope some of this information will be useful in finding answers to address the visible inaccuracies which have been identified so far

 

Tests carried out so far (as previously in this thread) have shown speed and depth of cut are very important

 

Tests with different 'stickiness' mats may show varying results with different materials and thicknesses

 

I have found that card and styrene of the same thickness from different manufacturers vary by quite a degree, which throws yet another variable into the arena

 

Looking forward to getting my hands on this machine - next week

 

Cheers

 

Ron

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(Snip)

 

So here's a list that I've found. They are assuming a knife that isn't dull:

  • Styrene - .050”, .010” and .015” can be cut.
  • Styrene - .020”, .040” (I haven’t tried thicker) can be scored and snapped.
  • Paper, tissue paper, labels and Card – all sorts of card can be cut pretty much up to cornflake packet thickness.
  • Fabric, including thin canvas – a number of materials could be cut (for wagon hoods for example).
  • Vinyl
  • Chipboard (very thin chipboard, about 1/16"!)

(End Snip)

 

Hi JCL,

 

A very interesting topic. Three items to ask, add and say.

 

Ask - what is the resolution of the cutter head? What's the smallest increment it can do.

 

Add - Google Sketchup can export it's files in .dxf format but don't know if it's one of the compatible versions!

(Just looked, AutoCad Release 12/13/14 and versions 2000,2004,2007,2010)

 

Say - Think that's a typo in post #11, should it be 0.005" ?

          <Quote>

          So here's a list that I've found. They are assuming a knife that isn't dull:

Styrene - .050”, .010” and .015” can be cut.

Styrene - .020”, .040” (I haven’t tried thicker) can be scored and snapped.

<Unquote>

 

Getting more tempted to get one the more the thread progresses!!  :secret: (May have to have a word with Santa) 

 

Dave

 

edit :- Not connected with this site http://www.softshop24.com/, and not used them at all either, but they are showing AutoCad2008 to download for £19.95

Edited by Shadow
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Hi Dave

 

Yep, .005", I'll get that changed.

 

I've just had a go at Sketchup, but I'm afraid its a couple of years since I used it, so I can't help there - anyone else?

 

With regards to resolution, the software seems to go to 0.01mm, but I think that, as mentioned in Ron's post above, the accuracy of the cutting has a number of different factors, the material to be cut and who manufactured it, the thickness of the material, the stickiness of the mat, the sharpness of the knife, and the offset of the knife that allows it to pivot. I think the one thing that everyone here has worked out is that cutting to these fine tolerance is as much as a an art as a science.

Edited by JCL
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