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PostPosted: Wed May 25, 2011 9:15 pm 
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When I set about my own tweed-style cabinet project, I had a few key questions for which I could not find satisfying answers. I looked and searched and read and asked questions - just couldn't make sense of the process. Nonetheless, I got the stuff and laid it all out and looked at it until the "now what?" finally turned into a "how, now"!

It turned out to be even more straight-forward a process than everyone had been trying to tell me it was. But - without the material in hand - it can still be hard to believe that it's a possible job for an inexperienced hand. A beginner's failure to trust? Anyway, I thought I'd run the risk of being useful and tell how it all went for me.

To start: this is the tweed that Mojotone sells, part number 8300001, "Fender Style Tweed Brown Stripe Coated/64" W". The same stuff appears to be available in Canada through Steamco Music, at similar prices. It's a quality product, and it's nice to work with; note that the back of the material has a coating, which is obviously flexible along its plane - that is, you can roll and bend and fold the stuff - but which makes the fabric rigid across its plane, allowing you to cut absolutely precise shapes with no fraying, and without worrying about stretching your carefully measured rectangle into a wonky parallelogram while you're cutting it out. And, the backing appears to make a more-or-less bleed-through-proof surface for adhesion.

I used the rolling cutter in the photograph, but, because of the backing, a straight razor-edge cutter will do the job perfectly.

Image

It was helpful to start by cutting precise rectangles to suit the dimensions of the cabinet, with straight edges at 45 degrees to the stripes. The edges on the material wander a bit away from 45 degrees, and won't work as reference lines.

To get the look "right", the stripes on all surfaces must slant from 10 o'clock to 4 o'clock, no matter how you look at the cabinet. By all reports, every original follows this orientation.

I kept my cabinet in front of me, looked at the material, made some measurements, double-checked the orientation of the stripes, and then cut the basic rectangles.


Last edited by quill on Thu May 26, 2011 12:26 am, edited 2 times in total.

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 Post subject: tools
PostPosted: Wed May 25, 2011 9:17 pm 
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Here's the tools I used (borrowed from a seamstress), to align the edges with the stripes:

Image

The stripes on the material I got are really straight, with almost no wandering at all over several feet.

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I thought I'd prepare my panels a bit before gluing with a few additional cuts, so the folding would go a little more easily. I'm willing to bet an experienced hand wouldn't need to bother with this step.

I used a red coloured pencil to make alignment marks on the back - which was not a good idea. I think an ordinary pencil would have been better; the red showed up on some trimmed edges, which wasn't too bad until it came in contact with the shellac, when it became quite unsightly - and it's a pain, trimming away material when you are trying to apply finish.

Image


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 Post subject: glue, and brush
PostPosted: Wed May 25, 2011 9:21 pm 
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This water-based contact cement is very good, and went on easily with the brush in the picture. It went on easily with the shown brush, cleaned up easily, and made a good bond between the tweed and the pine. I wanted to work inside a house while I did this, so organic solvents were out of the question - and I was thrilled at how well this glue worked. Almost no odour, and clean-up was simple.

Image_Image

However - I made a number of test pieces, to try out the glue and have some things ready for finishing tests, some on bits of pine and some on scraps of birch plywood, and I found that this glue did not work well with the birch plywood. In fact, a few days after application, I pulled the tweed off the plywood with almost no effort! Almost fell off. I really don't know why the plywood test pieces didn't work and the solid pine did. Maybe the pine was more porous?

I'd never worked with contact cement before, and it was a bit strange at first - you mean, I have to let it dry out before I put the parts together? - but after a couple test pieces, it all made sense. Apply to both pieces; two coats on porous surfaces; twenty to thirty minutes after last application, and the pieces are ready for bonding.

I did find that I had to use two coats of glue on the pine, while one coat on the tweed seemed to be enough - perhaps because of the backing on the tweed. So, I applied one coat to the part of the cabinet I was working on, while leaving the tweed dry, and let it sit for about twenty minutes, until dry to the touch; then I'd apply a coat to the tweed, then another coat to the cabinet, let them both sit until ready (another twenty minutes or so), and put them together.

Here's the side of the cabinet and the first piece of tweed, ready for application:

Image_Image


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 Post subject: the corners
PostPosted: Wed May 25, 2011 9:22 pm 
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The corners. Once the material is in hand, it is incredibly obvious what to do about the corners - but when I first started looking into this, I could not understand how this was done. Note - most do a "mitred" (or angled) corner seam, but I did one on a back corner and didn't care for the look - so I did a different thing, as the photos show. But all the photos I've seen of originals show cabinets with mitred seams in the corners.

Regardless of the preferred seam line - the point here is, the excess fabric in the corners is simply pressed together, and then trimmed away later.

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I used a razor knife to trim the corners.

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A caution about this method: I've had a lot of practice working with razor knives and am confident that, in most cases, I can do very neat, clean work, and do it safely - but with this stuff, I could not get the cuts right, as you can plainly see.

Image_Image

But even with my poor quality cuts, it's still clear in the photos that the trimmed edges did not fray and the seams lay together nicely. And even these bad cuts look good after shellacking and lacquering. But I think the proper tool for that step ought to have been a pair of fine-point scissors. Lesson learned.

Anyway - one side finished!

Image


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 Post subject: the top
PostPosted: Wed May 25, 2011 9:23 pm 
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Once both sides were done, I next applied the top. I wanted the material to wrap right around and cover the back of the top panel (the piece against which the top edge of the baffle-board is screwed). To prep the piece, I wrapped the fabric (with no glue on it, of course) around the front panel and clipped it in place.

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A bit of low-tack tape worked well to mask off the fabric - didn't want any excess glue at all on the fabric at all, as such a bit of spillage seemed likely to bugger up the finishing.

I think it looks really good when the stripes align across the seam, at this spot on the cabinet, so I fussed a bit here to get it that way - and it was quite a trick. I made coarse alignment marks on the tape, and planned to fine-tune once I had the glue ready.

Image_Image

Contact cement applied; as before, two coats on the pine, one coat on the trimmed top piece. Note the small pieces in the second photograph below that are prepped with contact cement at the same time as the top piece; these are for cutting into triangles and fitting into the gaps that will open up where the fabric is folded down around the curves in the top of the cabinet.

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A few wire hangers worked well to keep the glued surfaces apart until I had the stripes lined up at the front, and the tweed smoothly applied to the panel.

Image


Last edited by quill on Wed May 25, 2011 9:29 pm, edited 1 time in total.

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 Post subject: a bit more on the top
PostPosted: Wed May 25, 2011 9:25 pm 
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To fill the inside of a curve - as mentioned above - a small triangular insert is cut and applied. I don't have a good picture at this step, but there are some more details on this later on, taken of the upper back panel.

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Tape comes off, leaving a nice, clean seam.

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... mostly. It's wise to check for any glue that might ooze out along the seams, so it can be removed while still soft. I cleaned up this bit by rolling it off the fabric with a round toothpick.

Image

The stripes don't line up perfectly, but the compromise looks pretty good.

Image_Image


Last edited by quill on Thu May 26, 2011 12:41 am, edited 2 times in total.

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 Post subject: the bottom
PostPosted: Wed May 25, 2011 9:26 pm 
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Dry-fitting and trimming the bottom piece:

Image

Last piece, ready for application:

Image


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PostPosted: Wed May 25, 2011 9:27 pm 
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The back panel. I got a bit carried away with mine, and created some tweed-envelope challenges for myself - but why not push that envelope, given the chance? Why not indeed.

It is a big piece, given the part to be covered; but I wanted the inside of the panel covered with tweed for reasons that may or may not become obvious and it's not important anyway. What is more likely to be of some use in the following shots is the inside-corner details. Note again the small pieces that are prepped with contact cement at the same time as the large piece:

Image

Then, once the large piece is applied and wrapped around the inside corners - the need for the slits is made clear in the photo - the inserts can be cut to size and applied.

Image

Looks a mess from the inner surface, but from the outside, it's ok:

Image


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 Post subject: the results
PostPosted: Wed May 25, 2011 9:28 pm 
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The results so far:

Image
Image

After this - sealing, shellacking, applying the bonding layer and lacquering. I may follow up with a few of the things I learned about that, but there's already a lot of great, very professional instruction on all that readily available.


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PostPosted: Wed May 25, 2011 10:01 pm 
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THAT is Freakin' Amazing!!!

I owe you a BEvERage of your choice!

Thanks for taking the time to post that.

I have spent HOURS looking for some of those details.

LOVE THIS FORUM!!!!


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PostPosted: Wed May 25, 2011 11:21 pm 
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I have to say, that is a very well put together essay on how to tweed a cabinet. Everyone does it a little differently, but a first effort - excellent!!

Thank you for posting that.

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PostPosted: Thu May 26, 2011 1:19 pm 
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The best and clearest demonstration I have seen on how to apply tweed.

Your pictures are excellent also and help a lot to understand each stages of the procedure.

I would not have dared to try applying tweed to a cabinet. But after reading and seing your post I think I would.

Thank you for posting this.

The results you obtained are excellent.

I look forward to seeing the cabinet after the shellacing.


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PostPosted: Sun Jun 05, 2011 4:42 am 
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Thank you both so much for your kind read-through, and kinder comments.

But that's merely the fabric. The whole idea is to get it from this point:

Image

To this point - in your own preferred shade and hue, of course:

Image

Image

Here's how I went about finishing mine.

The last layers, the lacquer, were simple enough. I just bought two spray bombs of Mohawk Pre-catalyzed Nitrocellulose Lacquer (Gloss), and emptied them both onto the cabinet - in about five thinly sprayed coats, of course. I may take the sheen off with some 4/0 steel wool (but not just any old 4/0; the kind intended for woodworking and finishing, which has no or very little grease in it). But right now, I love it, just as it is.

And as I've insisted elsewhere, I'll be damned if the whole cabinet does not sound inexplicably and indescribably better wrapped in the tweed and finished with the shellac and the lacquer.

Leading up to the lacquer:

To the unfinished tweed, I brushed on two coats of Zinnser Universal Sanding Sealer - the exact product is pictured below - following the application and drying times on the product label to the letter;

Image

On top of that, I applied, with a brush, seven thin coats of a beautiful shellac - pictured above! the stuff in the jar - that I solvated and de-waxed myself;

On top of that, I applied, again with a brush, two more coats of the Zinnser Sanding Sealer, to create a "bonding layer", and became very upset by the colour shift caused by the slightly dark sealer;

And finally the lacquer, which weirdly seemed to reverse the sealer's effect on the colour - differing qualities of reflection or refraction between the products? - maybe. Regardless of why it happened - it was a relief!

I so wanted to stop after the seventh layer of shellac. The texture of this stuff is really interesting, like an organic glass ... almost feels alive ... and the colour is incredible, so deep and rich. But, it's not furniture, and needs the protection of the lacquer. Besides, the lacquer might age in an interesting way - especially the really hard pre-catalyzed stuff. It might get some great cracks in it!


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PostPosted: Sun Jun 05, 2011 4:44 am 
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Ok, ok. You don't have to make your own shellac. Lots of great pre-formulated shellac on the market, ready for your quick purchase and immediate use. But wait, just wait, until you see how much fun I had, making this stuff! And having made it, I was quite sure about what was in it, and what wasn't.


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PostPosted: Sun Jun 05, 2011 2:35 pm 
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That looks AWESOME!

You "wrote the book" for us.

Thanks again.

I can't wait to catch up to you! (My amp kit shipped today!!!)


(Note to self: remember to shellac and finish the inside of the cabinet too.)

Quill... if doing again, would you finish the inside differently? Or was it easy enough to do at the same time as the tweed?


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PostPosted: Mon Jun 06, 2011 4:34 am 
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Bruce, the only thing I would do differently on the inside of the cabinet would be to be a bit neater with the woodwork! I did not clean up the glue dribbles all that well, as I didn't expect it to matter - and it doesn't, really. I just decided on the fly to put a couple coats each of shellac and lacquer on the inside - with no bonding layer between, to test the compatibility, and there was no problem. I'm glad I did it, as I expect that those layers of finish on the inside may be giving the cab some of it's focus - but I really don't know, and can't say for sure. But it's nice that it's nice, on the inside, too.


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PostPosted: Mon Jun 06, 2011 4:38 am 
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Yes, I know, shellac comes in a can. I'm not telling anyone this is how it has to be done.

But I am telling everyone who will listen to be very careful with your solvent, both in choice of solvent and in its handling, should you decide to try it the really old-fashioned way. And I'm reminding everyone who will listen that it is the user's responsibility to read the Material Safety Data Sheet on any unfamiliar material. It's all online - no excuses.

Methyl Hydrate: http://www.pcsscreston.ca/MSDS/MSDS1/RECOCHEM/METHYL%20HYDRATE.pdf

Methyl Hydrate, Methanol, Methyl Alcohol - whatever you call it, whatever the water content, it's extremely toxic. And what a lot of people don't realize is that it's highly volatile and very, very small - so small that it'll slip right through even the very best organic-solvent respirators. Yes, it will dissolve the shellac - people will sell it to you, for this purpose, and tell you they use it all the time - in big shops, with hopefully the proper controls and PPE. The fact is, the hobbyist or home user just can't protect him or herself from this nasty stuff by any simple, convenient method - except that most convenient method of all, which would be to just use something else.

Denatured Alcohol: http://www.sciencelab.com/xMSDS-Alcohol_denatured_with_IPA_and_MeOH-9922820

Also Denatured Ethanol, mixed with additives that make it undrinkable and therefore slightly more simple to regulate. But still - it's really hard to find, at least in my area. And I've seen mixtures that contain methanol ... I don't like that ... also mixtures with benzene and toluene - I like that even less - but the quantities of the really bad things are small, and I'll use it if, for some reason, it happens to be right there in front of me - before I found something I liked better, I did find some; Mohawk Finishing has a thing called "Shellac Reducer" that is a mix of Denatured Ethanol with other things - the can's out in the shop, I think it was isobutanol and isopropanol, but I'm not sure, and it doesn't matter. I will use it, sometime. What matters is that you be informed about the materials you are handling. Don't make me start telling you construction-site horror stories ...

Isopropyl Alcohol, 99%: http://www.ee.iitb.ac.in/~nanoe/msds/ipa.pdf

It's not perfectly safe in some ideal, water-like way, but it's cheap, and it's not regulated - you can buy it in any drugstore; it hasn't shown itself to be carcinogenic in lab tests, and diluted a bit, it won't kill the little fishes; you can breathe in a bit of it and not be in terrible, immediate danger; and it does a beautiful job of solvating the shellac. It also seemed to me to almost drive the wax out of solution. Just worked great for me.


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PostPosted: Mon Jun 06, 2011 4:59 am 
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So! Here's the flakes - aren't they beautiful?

Image

Of the options available at the shop I was at (Mohawk Finishing in Vancouver), I just bought the inexpensive orange ones; I enjoyed looking at the beautiful blond flakes, but they were four times the price, and the garnet were expensive, too.

Did you know that shellac is the secretion of the female lac bug? That the lac bug eats sap from trees, and that the time of year and the weather and all kinds of other random occurrences affect the colour and the quality of the shellac? And that the stuff is actually edible? Isn't that wild? Isn't that beautiful?

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I found that a nice ratio for reasonably easy solvation was fifty grams of shellac in one litre of 99% isopropyl alcohol. In a closed glass jar, with a little shaking every so often ...

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... it went completely into solution in about a day.

But at that point, it's not yet ready. It needs a chance for the wax to fall out, which in my case took another whole day. I would look at it every so often and watch the drops forming and slowly falling down; I think isopropanol is quite dense, and the wax only slightly more so - anyway, it was interesting for your very patient and probably quite mad Quill.

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Here's a couple shots showing the precipitated wax - aren't you just on the edge of your seat? it's sooo fun:

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With a light touch and a cheap baster, it's a simple task to draw off the clear solution and transfer it to a clean jar - and it might need to be done a couple of times; one jar I think I went through the process three times to get it really clear:

Image

And there's the shellac, in the jar on the left.


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 Post subject: The sealer
PostPosted: Mon Jun 06, 2011 5:02 am 
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Some sealer on the tweed is probably a good idea. I think it helped a lot; I did a test piece without it, and it was quite blotchy and soaked up a ton of shellac without developing much colour.

But as I've already complained, I didn't like the coloration of the Zinsser sealer at all. Again - sorry if this image is tiresome, but you must admit, it's useful having it right here, for ease of comparison - here's the bare tweed:

Image

And here's the tweed after two coats of sealer:

Image

Image


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PostPosted: Mon Jun 06, 2011 5:18 am 
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The development of the colour is beyond me to describe or otherwise represent; it's frustrating, because who doesn't love colour as much as music? But both are beyond description - anyway. The grey stones help to give a bit of reference, at least for the first few photographs. Of course, the light was changing through the day, and the pictures of the sixth and seventh coat are useless. But the last layer of shellac is presented again, against a white-ish background, and you can get some idea from that.

What you see is one hundred grams of shellac, solvated into two litres of 99% isopropyl alcohol, dewaxed (somewhere between twenty-five and fifty grams of wax came out of the solution) and brushed progressively through seven coats onto the cabinet. And there are I think three coats on the inside, too, just for the fun of it.

Here goes ...

First coat:
Image

Second coat:
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Third:
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Fourth:
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Fifth - each time, pictured dry, by the way, just before application of the next coat:
Image

Sixth - it was completely dark, apologies for the complete loss of useful reference:
Image

Same problem with the last coat:
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I hereby reappropriate the term, "Shellacked!" for the sole and exclusive use of craftspeople and serious hobbyists everywhere. For here is a thing that, for all intents and purposes, represents the results of a proper shellacking (and not yet any lacquer). Ain't it a lovely thing - and a lovely word!

Image


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