A Hands- on Tutorial by

Orville and Robert Milburn

재 료

French polishing에 쓰이는 도구와 재료는 매우 적고 간단하다. 사실 몇 달러만 투자하면 당신도 많은 장비(악기)에 쓸 만큼을 얻을 수 있다. 이 글 끝에 필요한 재료들을 구입할 수 있는 곳의 목록을 달아두겠다.

쉘락

락은 락 딱정벌레라고도 하는 '코쿠스 랔카'라는 곤충에 의해서 모아지는 자연물질이다. 이 물질은 곤충의 집 역할을 하는 많은 종류의 나무에서 모아진다. 락(Lac)은 나무의 가지와 껍질에서 얻어진다. 수확된 락은 정제되고 따뜻한 락 주머니에 싸인 수공의 형태(쉘락)를 포함해 수많은 형태로 가공된다.

Shellac flake on left and ground shellac on right. The shellac flakes were ground using a coffee grinder. Shellac is non-poisonous and is approved for use in food by the FDA.

수확된 락의 주머니는 열에 의해 가열된다. 락이 녹으면 락 주머니를 락이 주머니 바깥쪽으로 새어 나올 만큼의 충분한 압력으로 교압기를 이용해 짠다. 락의 많은 양은 쉽게 저장하기 위해 바삭바삭한 조각으로 부숴지기 쉬운 얇은 판으로 가공된다. 쉘락은 대개 공업에 쓰이는데 페인트가게나 기자재점에서 살 수 있는 일부는 쉽게 사용할 수 있도록 가공되어있다. 쉘락 조각의 상당부분은 고급 수제품 전문 마무리공들에게 들어간다. 시간이 흐르면서 '쉘 락'은 '쉘락'으로 불리게 되었다. 쉘락이 수확되고 가공되는 과정에 대한 가장 좋은 설명서는 "American Lutherie No. 54, summer 1998."이다. 이것은 미국 최고의 Luthier이며 French polisher 중 한 명인 Cyndy Burton이 쓴 것이다. 우리가 쓸 쉘락은 조각으로 팔고 있는 것이다. 쉘락 조각은 적어도 네 가지가 될 수 있다. 쉘락의 타입은 색깔을 표시하는데 밝은 것부터, white, blonde, orange, dark(garnet)이라고 부른다. 일단 쉘락을 필요한 만큼만 알콜에 녹인다. 용해된 쉘락은 유효지속시간(shelf-life)이 짧기 때문이다. 쉘락과 알콜 혼합물은 시간이 지나면 습기를 흡수하면서 가수분해되어 질이 떨어진다. 수개월 내에 사용할 만큼만 섞는 것이 바람직하다. French polishing에는 가게에서 파는 기혼합 쉘락이나 캔에 담긴 것을 사용하면 안 된다. 기혼합 쉘락에는 유효지속시간을 늘리고, 유동성을 높이고 브러쉬를 사용할 수 있게 만들기 위해 건조를 지연시키는 첨가물이 많이 들어있다. 믿을 만한 가게에서 양질의 쉘락 조각을 사기 바란다. 이 글 끝에 쉘락 조각을 살 수 있는 곳의 이름과 주소를 적어 두겠다.

알콜

알콜을 많이 사용하게 될 것이다. 알콜은 쉘락 조각을 녹이는 데, 희석하는 데, 공극을 메꾸는 데, 그리고 French polishing의 다른 과정에도 쓰일 것이다. 양질의 기자재점에서 파는 알콜이면 충분하다. 하지만 일부 사람들은 변성과정에서 알콜에 첨가된 물질에 예민하다. 변성알콜은 메탄올이 약간 들어간 에탄올이다. 무엇보다도, 변성알콜은 어린이의 손이 닿지 않는 안전한 곳에 닫아두어야 한다. 사려깊은 사람이라면 알콜 취급점-또는 주류점-에서 순수한 알콜을 살 것이다. 이렇게 하면 많은 돈이 들긴 하지만 순수한 에탄올을 구할 수 있다. 변성알콜의 증발하는 정도가 좀 문제가 될 수 있다. 알콜의 라벨을 잘 보고 메탄올만으로 변성작업 된 에탄올을 구입해야 한다. 다시 말하지만, 필요한 만큼만 섞어야 한다. 알콜은 열어두면 증발하면서 수분을 흡수하게 되므로 순도를 유지하기 위해 병의 뚜껑을 닫아 두어야 한다.

속돌(Pumice)

Pumice는 갈고 pore filling하고 연마하는 데 쓰인다. Pumice는 다른 마무리작업에서 광택재로 쓰이기도 하며 특수도장재상점에서 구할 수 있다. 여기서는 아주 좋은 FFFF등급의 속돌을 쓴다. 처음에는 pore filling과 Pumice를 사용하는 것이 어려울 수 있지만 익히고 나면 작업이 쉽게 진행될 것이다.

These are the main materials used for French-polishing. The containers are chosen to aid in dispensing proper amounts of the various materials.

기름

올리브유는 French Polish를 할 때 윤활유로 쓰인다. 쉘락에는 뮤네카(정확히 뭔지는 모르겠습니다만 후반부에 만드는 법이 나옵니다)나 접은 패드(부드러운 소재의 두툼한 조각을 pad라고 하는데 이것도 그림 참조하시기 바랍니다)만 사용해야 한다. 뮤네카는 쉘락이 제대로 퍼지게 하기 위해 나무 표면에 잘 눌려야 한다. 이렇게 잘 누르는 것은 각각의 미세한 쉘락 층이 기존의 쉘락 층과 융합되어 풍부하고 깊은 칠을 만드는 작업이기도 한데, 쉬운 작업이 아니다. 기름을 현명하게 사용하면 뮤네카가 붙거나 끌리는 일 없이 나무에 강하게 누를 있다. 쉘락이 표면에 앉으면서 기름은 칠을 통과해 위로 올라오려고 한다. 따라서 칠의 아래 갇혀 칠을 망치지 않는 기름을 사용하는 것이 중요하다. 순도 100%의 올리브유(100% virgin olive oil)를 쓰는 것이 바람직하다. 왈넛오일(호두기름)이나 베이비오일, 파라핀 오일 등은 산화방지제나 향신료 같은 불순물이 포함되어 도장에 문제를 일으킬 수 있다. 따라서 초보자는 우선 순수한 올리브유를 사용해야 한다.

연마용구

French polishing을 위한 세부사항과 기타(guitar)의 준비사항도 도장 그 자체만큼 중요하게 다루겠다. 모든 등급과 형태의 연마도구 목록이다;

• 220 grit open-coat dry sandpaper 3M "Gold" 216U
• 320 grit open-coat dry sandpaper 3M "Gold" 216U
• 400 grit wet/dry automotive sandpaper 3M "Imperial 401Q
• 800 grit wet/dry automotive sandpaper 3M "Imperial" 401Q
• 1200 grit wet/dry automotive sandpaper 3M "Imperial" 401Q
• Micro-Mesh "Cushioned abrasive" 3200
• Micro-Mesh "Cushioned abrasive" 3600

위의 연마도구가 당신이 처음으로 French polishing을 완성하는 데 필요한 전부이다.

Here are some of the sanding blocks we use in leveling the finish. In the back is a large wooden block with a cork pad. Next to it is a mahogany block with a round edge to smooth the inner surface of the string slots. Also shown are various rubber blocks. Some are made of pink pencil erasers. Note the various sizes and shapes.

천

일단 모직물이나 수술용 거즈를 내부재로, 티셔츠 재료와 같은 100% 면직물을 외부재로 하여 문지르개 또는 뮤네카(헝겊인형의 스페인 말)를 만든다. 울이나 거즈를 쓰는 것은 뮤네카 안의 쉘락이 손이 누름에 따라 바깥으로 빠져 나가는 것을 막기 위해서다. 깨끗한 면 거즈나 순수한 모직물을 내부재로 쓰지 않는다면 쉘락은 제대로 퍼지지 않을 것이다. 인조직물이나 인조 합성물은 뮤네카에 절대 쓰면 안 된다. 낡은 티셔츠는 외부재에 적합하고 모직양말 조각은 내부재에 적합하다. 부드러운, 닦아낼 천(wiping clothes)도 많이 준비해 둬야 한다. 직물점에서 한 야드쯤 되는 티셔츠 소재를 좀 나으면 두어 벌의 낡은 티셔츠를 준비하고 싶을지도 모르겠지만 그렇게 많은 양은 필요 없다. 기타와 닿는 것들은 전부 불순물이나 먼지가 없는지 확인해야 한다. 아주 작은 먼지 입자도 도장에 눈에 띌 만한 상처를 낼 수 있다. 도장은 굳기 전엔 아주 약하다.

세정및 광택제

전에 말했듯이, French polishing에는 광택재가 전혀 쓰이지 않는다. 그러나 도장을 끝내고 나서 남은 기름 찌꺼기를 제거하고 지문을 없애기 위해 악기를 닦을 필요가 있다. 이를 위해서 ‘Meguiar’s No.7 Show Car Glaze’를 사용한다. Meguiar’s #7은 연마제가 들어있지 않으므로 지속적으로 반복해서 써도 안전하다. 좀 더 강한 광택재가 필요하다면 ‘Meguiar’s #9 Swirl Remover’를 쓰면 된다. #9은 고급의 연마제가 들어있어 도장을 일부 제거할 것이다. 미세한 상처들을 제거하기 위해 사용하기에 알맞지만 지속적으로 쓸 수는 없다. 이들은 도장이나 나무에 상처를 낼 수 있는 실리콘 성분이 전혀 첨가되지 않은 양질의 상품들이다. 자동차 부품점이나 자동차 도색점에 가면 구할 수 있다.

기타

• . 폭 1”, 길이 5/4, ?인치 두께의 갈아낼 조각(rubber sanding block). 정확히 사각형인 나무조각에 아래쪽에 코르크가 붙어있으면 충분하다. 대개의 페인트 가게에 가면 작게 자를 수 있는 ‘갈아낼 조각’을 판다. 다른 데서도 비슷한 것들을 구할 수 있을 것이다. 코르크를 붙일 때는 에폭시를 이용해서 붙여야 한다. 다른 접착제는 기름과 용매에 의해서 떨어질 수 있다.
• 압착할 때 쓸 작은 병도 쉘락과 알코올을 퍼뜨리기 위해 중요하다. 작은 풀통 정도면 적당하다. 최소한 두 개는 준비해야 한다.
• 뮤네카와 문지른 천들이 마르지 않게 저장할 밀폐용기가 있으면 좋다.
• pumice를 퍼뜨릴 소금통 하나(salt shaker)
• 기름을 퍼뜨릴 약통 하나(medicine dropper bottle)
• 나프타 용매 1.14리터 정도(a quart)
• 기타 넥 지지대. French polishing을 하는 동안 기타는 넥으로 지지되어야 할 경우가 많다.
• 강력접착제와 5분에폭시(SuperGlue and 5-minute epoxy)
• 스탑워치
• 작은 깔대기
• 타이핑 페이퍼

끝으로, 작업할 공간이 필요하다. 당신은 작고 밝은 곳이나 집에 남는 방을 작업실로 쓰려고 할지 모르겠다. 온도가 적당하고 먼지가 없는 곳이 적절하다. 먼지를 좀 적은 구석이 좋을 것이다(공기중의 먼지는 작업 후반에 고려한다). 이제 French polishing에 필요한 것들을 전부 살펴봤다. 자 에제 시작합시다 …

기타 손질하기

모든 피니시(도장)의 질은 그 악기가 어떻게 손질되었는가에 크게 영향을 받는다. 좋은 도장을 사용할수록 결점(악기의 흠 같은 것)은 더 뚜렷이 드러날 수 있다. 지금은 목재 다루는 법은 깊이 다루지 않고 기타가 잘 마무리되어 있고 사포작업도 잘 되어 있으며 각 틈이 제대로 메꿔져 있다고 간주하겠다. 가장자리 장식과 바인딩은 완전히 평면을 이루고 있어야 한다.

Detailing the guitar edges with a sanding "stick".

백과 사이드, 탑은 로제트를 포함하여, 상감으로 처리된 모든 부분과 만져봤을 때 가능한 한 평면을 이루고 있어야 한다. 도장작업에 들어선 다음에 어떤 흠을 발견한다면 괜한 일을 더 해야만 한다는 것을 명심하라. 눈으로 변색되거나 흠집 또는 상처가 난 부분, 기타 흠이 있는 부분들을 점검하라. 점검이 만족스럽게 끝났다면 기타 전체를 나프타 용액으로 문질러 닦는다. 예전에 발견하지 못했던 흠들이 놀라울 만큼 많이 보일 것이다. 이것들이 당신이 French polish를 시작했을 때 나타날 흠들과 같은 것이다. 이 작업에 나프타를 이용할 때 얻는 이점 중 하나는 나프타 용액이 상당히 천천히 증발한다는 점이다. 주의가 필요한 부분에 살짝 표시하는 데는 많은 시간이 걸린다. 표시한 부분들을 마른 220 grit open-coat 사포로 문질러라. 220 grit 사포는 기타 탑의 두께를 바꿀 만큼 강하지는 않다. 사포로 살살 문지르는 정도로도 작은 상처들은, 기타의 음색에 손상을 주지 않으면서, 없앨 수 있다. 만약에 꽤 크게 팬 자국이나 긁힌 상처가 있다면 사포로 문지르기 전에 증기를 조금 쐬도록 한다.

Using cyanoacrylate adhesive (SuperGlue) to fill small defects in the rosette.

사포질을 좀 쉽게 할 수 있을 것이다. 상처에 증기를 쐬기 위해서는 그 부분을 살짝 적시고 젖은 천을 그 지점에만 올려놓는다. 다리미를 켜고 그 흠을 덮고 있는 천 위에 댄 다음 몇 초간 있는다. 그 부분을 말린 다음에 220 grit 사포로 위와 같은 작업을 한다. 깊이 파인 곳은 ‘cyanoacrylate’(강력접착제)나 에폭시로 메꾼다. 눈에 띄는 파임이 있을 때는 5분에폭시와 사포질에서 나온 가루를 섞어 메꿀 수 있다. 평평하게 사포질을 했다면 눈에는 보이지는 않지만 좋은 수리가 된 것이다. 나프타 용액이 증발하기 전에 표면의 작은 변색 부분들을 확인해야 한다. 결과가 만족스럽다면 기타를 젖은 천만으로 닦는다. 이 작업은 기타의 갈린 찌꺼기들을 제거하며 결을 살짝 드러낼 것이다. 또한 나프타 용액을 사용했을 때 보이지 않던 융기한 부분들을 드러내줄 것이다. 기타가 완전히 마른 후에 400 open-grit 의 마른 사포로 표면 전체를 문지른다. 마지막 사포질을 마무리 한 다음 표면을 나프타 용액으로 닦아내고 완전히 말린다.

쉘락 녹이기

우리의 쉘락을 준비할 시간이다. 다음 단계에서는 알코올과 쉘락 조각의 적당한 ‘컷’이 필요하기 때문에 적절한 컷을 얻기 위한 알코올과 쉘락의 혼합 비율을 알아야 한다. 1파운드 컷은 1파운드의 쉘락 조각을 1갤런의 알코올에 녹인 것을 의미한다. 만약 2파운드 컷(두껍거나 무거운)을 원한다면 쉘락 조각 2파운드를 알코올 1갤런에 넣는다. 전에 말했듯이 단기간에 쓸 수 없을 만큼 많은 양을 혼합하는 것은 안 좋다. 게다가 2파운드 컷 1파인트면 기타 하나를 완성하는 데 충분한 양이다. 적당한 양으로 만들기 위해서 쉘락과 알코올의 양을 비율에 맞게 나누어보자. 1파운드 컷은 쉘락 조각 16온스를 알코올 128온스에 녹인 것이다. 이것은 1온스의 쉘락 조각이 8온스의 알코올에 녹은 것과 같다. 따라서 적절한 2파운드 컷의 양은 쉘락 조각 2온스를 알코올 8온스에 녹여 만들 수 있다. 여기서 최종 혼합물을 결정적으로 망칠 정도가 아니라면 비율의 정확성에 지나치게 신경 쓸 필요는 없다.

Various shellac solutions. From far right: Very thin cut of "luna" shellac, 2-pound cut of "luna", 2-pound cut of garnet shellac, olive oil for comparison.

쉘락 조각을 알코올과 섞은 다음 완전히 용해되도록 24시간 동안 둔다. 쉘락 조각을 커피 믹서(분쇄기)에 넣고 갈아서 고운 가루로 만들어 사용하면 금방 쓸 수 있다. 가루는 조각보다 몇 배나 빨리 녹을 것이다. 어느 정도의 진동이나 적절한 열도 이 과정에 필요한 시간을 단축시킬 수 있다. 혼합물은 물중탕으로 가열하며 열판이나 레인지는 사용하지 않는다. 이렇게 하면 몇 시간 만에 용액을 준비할 수 있다. 용해됐으면 쉘락을 짜낼 용기에 옮겨담는다.

주의사항

• 작업실에서는 담배를 피우지 않는다.
• 난로 등의 직접적인 불이 있는 방에서 작업하지 않는다.
• 통풍이 적당히 되는 공간에서 작업한다.
• 쉘락과 알코올을 어린이가 만질 수 없는 곳에 보관한다.

단위 :
1 ounce = 30 grams
1 gallon = 128 ounces or 3840 grams
1 gallon = 8 pints
1 pint = 16 ounces or 480 grams

기타 실코팅(seal-coating)하기

이제 French polish를 위한 기초작업을 할 준비가 됐다. 이 기초작업은 ‘spit-coat’, ‘wash-coat’, ‘seal-coat’라고 부르는 작업이다. 목적은 세 가지이다. 기타에 칠할 쉘락 미세층에 점성 있는 표면을 제공한다. 쉘락은 점성이 강해서 세계 최고의 우드 실러(wood-sealer)로 알려져 있다. 둘 째, 백과 사이드의 기름과 염료에 의해 상감장식, 가장자리 장식, 로제트 등이 더러워지는 것을 막아준다. 세째 Pumice와 목재염료가 나무의 공극에 잘 섞여 들어가게 해 준다.

Sealing the edges of the back of a rosewood guitar. You can easily see the seal coat left by the wet pad.

첫번째 작업은 가장자리 장식과 바인딩, 백의 기다란 조각(백 가운데로 지나가는 거 말하는 건가요? Back strip이라고 표현되어 있습니다-이하 백스트립)을 막는 것이다. 이것으로 나무의 기름과 천연염료가 상감장식을 더럽히는 것을 막을 수 있다. 넉넉한 티셔츠 재료를 4” x 4”의 사각형으로 자른다. 4” x 4”를 반으로 접고 한 번 더 잡는다. 쉘락 혼합물(이하 쉘락)이 든 짜는 병으로 접힌 천의 모서리를 충분히 적시고 기름 한 방울을 그 자리에 떨어뜨린다. 기타의 백을 먼저 한다. 기타의 윤곽을 따라 가장자리 장식과 바인딩을 먼저 문지른다. 이 작업은 한 번에 한 쪽 반씩만 한다. 중간에 멈추거나 좌우로 흔들림 없이 한 방향으로 이루어져야 한다. 빠르고 정확하게 되었다면 상감장식에 색이 들지 않을 것이다. 천을 깨끗한 쪽으로 바꾸어 쉘락과 오일을 보충하여 위와 같이 다른 반을 작업한다.

Sealing the edges of an instrument. Note the "field" is already sealed. Here we are sealing the purflings and bindings a second time.

기타의 양쪽을 다 했으면 천을 깨끗한 쪽으로 돌려접고 백스트립을 직선으로 작업한다. 깨끗한 면으로 천을 다시 돌려접고 쉘락과 기름에 적신다. 원을 그리면서 백의 작업하지 않은 부분 즉, 넓은 면을 문지른다. 이제 천조각은 나무에 의해 더러워졌을 것이다. 이제 그 천을 내려놓고 똑 같은 천 조각을 하나 더 만든다. 깨끗한 천으로 힐조인트(heal joint)의 각 면을 한 방향으로 문지른다. 기타를 옆으로 세워놓고 사이드의 가장자리 장식과 바인딩에 백에서와 같은 작업을 한다. 가장자리가 되었으면 넓은 부분을 한다. 각 단계마다 천을 깨끗한 면으로 바꿔 접는 것에 주의한다. 넓은 부분을 다 했으면 더러워진 천을 버린다. 기타의 다른 면에 같은 작업을 반복한다. 참고: 밝은 색의 나무가 더러워진다 싶으면 언제든 천을 버린다. 사이드를 끝냈으면 깨끗한 면으로 로제트와 탑의 가장자리 장식에 작업을 한다. 깨끗한 천으로 탑의 넓은 면을 작업한다.

An example of a folded pad after it has been used to seal a section of a guitar edge. This coloration will contaminate white purflings and light wood.

더 이상의 깨끗한 면이 없을 적마다 새 천을 만들어야 한다. 이 작업을 기타 전체에 세 번 반복해서 한다. 각 부분마다 천을 깨끗한 면으로 바꿔 접는다. 더러워지는 것을 막기 위해서 탑에 작업할 때마다 새로운 천을 쓰는 것도 좋은 생각이다. 전체 기타를 실코트 하는데 약 15-20분이 걸릴것이다. 첫번째 실코팅이 되었으면 가장자리 장식을 살핀다. 만약 가장자리 장식에 색이 묻었다면 작은 고무조각과 올리브유를 이용해서 닦아내거나 400 번의 젖은 또는 마른 사포로 살짝 문지른다. 스크레이퍼에 익숙하다면 변색된 부분을 긁어내고 쉘락을 다시 입힌다.

Removing purfling contamination using a small scraper made from a heavy single-edge razor blade

약 30분 정도 첫번째 실코팅을 말린 뒤 과정을 반복한다. 쉘락을 입힐수록 천은 조금씩 덜 더러워질 것이다. 이것은 가장자리 장식이 잘 밀폐되었으며(well sealed) 쉘락의 기초작업이 잘 되고 있다는 표시이다. After applying three spit coats to the entire guitar, we will take a small artist's brush and again paint all of the purflings to provide additional protection for all of the inlay work since pumicing acts as an abrasive and can burn through the shellac to the purflings. In addition to painting the purflings, you may wish to apply a wash coat to the classical guitar machine slots as well.

Filling the grain and pores

Pumice is of volcanic origin and has been around for hundreds of years and used for a variety of purposes. Before modern technology developed the fine sandpapers that are common in the marketplace today, pumice along with many other materials were used as abrasives. The wood finisher used a felt block and often a leather-covered block with pumice powder to sand the wood smooth. Pumice was also used to polish shellac and resins to fine high-gloss finishes. The pumice for the wood finisher was ground and filtered into many different grades and sizes much the same way as we buy different grades of sandpaper today. No doubt, at some time during sanding, it was discovered that the pumice not only acted as an abrasive but filled the wood grain at the same time. The pumice method of grain filling has been with us for hundreds of years and is still the preferred method of grain filling for many wood finishers.

Lets start our grain filling now . . .

After sealing the instrument is allowed to "gas out" (remaining alcohol is allowed to evaporate) for a few hours. We are then ready to fill the pores and grain. This is the pumicing operation. At this point we should mention that there are some species of wood that do not require grain and pore filling. The top of the guitar will not have to be grain filled. Spruce, Cedar, and Maple are examples of "closed-pore" woods which do not have to be grain filled, and with some experience you will recognize woods which require grain filling and those that do not. Most rosewoods have large, open pores and will need to be filled. If the pores of an open-pored wood are not filled properly the finish will slowly shrink back into the pores. The result will be thousands of tiny craters in your finish.

Applying the Pumice

We will not be using any new shellac during the entire pumicing process. This is very important- additional shellac during the pore-filling process will inhibit the operation. We will be using the already dry shellac "spit coats" that we have previously applied to the guitar. All that is used is the muneca loaded with alcohol and a very small amount of pumice applied to the muneca surface.

The muneca is touched to a bit of pumice on paper. The pumice is then distributed over the surface of the muneca with a finger.

The alcohol will dissolve the dry shellac while the abrasive action of the pumice is pulling off microscopic wood fibers which will be deposited into the pores of the wood along with the natural colored oils. Do not use any shellac while pumicing. As Eugene Clark says, "You would be better off if someone stole your shellac at this point." Your muneca must touch the surface of the wood. A heavy layer of shellac would prevent this.
The actual pumicing procedure is simple and is as follows . . .
Add a generous amount of alcohol to the surface of the muneca. Be careful not to overdo the alcohol (about 10 to 12 drops is what we call generous). You will always have to add extra alcohol to a dry muneca. Once wet, however, just a few drops(4 or 5 for each recharge will be enough). Note that we will always load the muneca from the outside. Tap the muneca against the back of your hand to help distribute the alcohol throughout the wool pad. Fill your salt shaker with pumice and sprinkle a small amount onto a sheet of typing paper. Now, use the bottom edge of the muneca to "bite" off a small portion of the pumice. With the pumice sticking to the bottom of the muneca, add a few drops of alcohol (4 to 5) and rub with your finger until the pumice becomes transparent. This "clears" the pumice. NEVER APPLY PUMICE DIRECTLY TO THE SURFACE OF THE INSTRUMENT. Beware of clever gimmicks such as powder puffs and "pounce bags" used to add pumice directly to the surface of the instrument. They are unnecessary and silly.

The pumice is made transparent by wetting it with a few drops of alcohol.

Adding pumice directly to the wood surface will result in the particles of pumice showing through the finish. In addition, putting pumice directly on the instrument will result in piles of pumice that cannot be removed except by sanding. Any dry sanding at this stage may also cause the pumice to show through the finish. Now, press the muneca firmly to the guitar's surface and rub in small circular patterns. Do one small area at a time changing to a direction of rotation often. This is a good time to practice changing directions without stopping the muneca. Never use straight and forward pressure with the grain. This will tend to remove the material from the pores. Mentally divide the surface into small areas and finish these sections one at a time. Add only a little alcohol and pumice as you work. Soon you will see the grain being filled. You can actually feel and hear the muneca sanding the surface of the wood. When the muneca runs dry, recharge with alcohol and add a "bite" of pumice. Continue this same pattern over and over until you can no longer see the grain and pores of the wood. Be especially careful not to add too much pumice. You should be able to see any excess pumice on the surface of the guitar. It is now obvious why only a small section should be pumiced at a time.

The grain is filled by moving the pumice-loaded muneca in small circular motions. Direction should be changed often. The grain is best filled when the muneca is moved against the grain direction. Don't move the muncea in long strokes parallel to the grain.

Any excess pumice can be moved to an area of the guitar that needs the additional pumice. If you accidentally add too much pumice, add more alcohol and work the excess pumice to an area of the guitar that needs additional pumicing. The pumice is an abrasive and will tend to wear the muneca cover very rapidly. It will be necessary to provide a new cover periodically. When the pores on the back of the instrument are satisfactorily filled, turn the guitar on its side and repeat. Use only small circular motions changing from clockwise to counterclockwise movements as you work. When you encounter the heel joint, change to a small folded cloth and wet with alcohol. Add a bit of pumice and rub it into the cloth until it "clears." Rub the pumice onto the sides up to the joint until the grain has filled. This area of the guitar is perhaps the most difficult to pumice and may require 3 or 4 attempts before the pores are well filled. Next, you may want to pumice the neck of the guitar. Many luthiers would rather leave the neck natural without filling the grain. If you do choose to fill the grain, complete it exactly the same as if were the back or sides of the guitar. If the neck is Spanish Cedar or Mahogany be especially careful to "clear" the pumice as you work. Remember, don't use shellac as your pumice.

REVIEW

Now lets review the grain filling procedure . . .

1. First, "seal-coat" or "wash-coat" all of the purflings with 3 sessions of shellac, being careful to protect the inlay work from color contamination. Seal the "field" areas similarly.
2. While spit coating, fold your shellac cloth often to avoid discoloring the inlay work. Pull the cloth in one direction with a single motion. After spit coating the guitar three times, you can then paint more shellac on the purflings using a soft camel hair painter's brush. Do this if you are having contamination problems.
3. Use no shellac or oil during the grain filling process. The spit coats of shellac with the alcohol, combined with pumice, will be all that is necessary to fill the grain.
4. Remember to "clear" the pumice. Dab the wet muneca on a little sprinkle of pumice. Add additional alcohol and rub the pumice evenly on the bottom of the muneca to clear the pumice.
5. Always load the muneca from the outside with alcohol. Be careful to not add too much alcohol. 10 to 12 drops to a dry muneca and 4 to 5 thereafter should be all that is necessary.
6. Using firm pressure, rub the muneca onto the surface using circular motions and change directions often.
7. Grain fill only small sections of the guitar at a time. Any excess pumice can be moved to an unfinished area using a little alcohol.
8. Inspect your work often and use very little pumice as you work. Do not get impatient and try to hurry. This may result in more work in the long run. A bright lamp at a low angle will help visualize unfilled pores.

Making the muneca

Lets start our project by first making our muneca. There are a number of ways that a muneca can be made but to simplify the task we will explain several ways that we make ours.

A muneca cover made of several layers of wool.

First, cut three round disks out of a thick wool sock or sweater. Be sure that it is 100% wool. If it contains any synthetics it may not dispense the shellac properly. The first disk should be about 1 & 1/4" in diameter.The second one should be 3/4" in diameter and the third about 1/2" in diameter. Now, stack all three together starting with the largest going down to the smallest. With a needle and thread sew the edge of the large disk to the top of the small disk. Do not pull the edges tight. Sew them just enough to keep them together. Next, cut a 4" x 4" square of t-shirt material and lay it flat on the table. Lay the stack of wool with the large flat side in the middle of the square.

A muneca core made of 18 inches of cotton gauze.

Grasp the four corners of the t-shirt material and twist all four corners until the encapsulated wad of wool lays firmly between the thumb, index, and forefinger. Another way to make the muneca is to cut a small wad of wool from a wool sock or sweater about 3" x 3" square. Form into tightly in the muneca cover as we did before. Attach a rubber band around the base of the core and really flood it with some 2-pound cut shellac. Let the muneca sit in the open air for several hours. Once most of the alcohol evaporates the core will retain its shape. Cotton is an alternative to using wool for the muneca core. Surgical gauze (from a pharmacy) makes a good core. Cut about 18 inches of gauze and begin by

Before using the muneca, twist it tightly to make it harder.

folding one end over and over again. Rotate the folded portion after each wrap while attempting to make the core as tight as possible. Ideally, you would like to make a finished core that has a somewhat rounded bottom and about one-half as high as it is in diameter. Once the gauze has been wrapped into the shape and size you want, wrap a cover around it and hold it in place tightly with a rubber band. Flood it with shellac and let it evaporate as in the above example. In both these examples you will probably want to make new covers rather than use the covers with the dried shellac as they will take quite some time to soften. Always put your munecas into a sealed container when you are not using them. Add a few drops of alcohol to the container. This will help prevent the muneca from getting hard. Also take care to change the muneca cover whenever it becomes damaged (often when you use pumice) or stained.

BODY SESSIONS

Assuming that the pumicing and grain filling went well and has been completed, we now begin our French polishing "sessions". We use the term sessions rather than "coats" such as a furniture finisher would use. We will be applying literally hundreds of microscopic layers of shellac to the instrument resulting in one single amalgamated layer of shellac. As you can see, in the case of French polishing, the term "coats" does not apply. During each session we will apply dozens of layers of shellac and will complete as many sessions as it takes to "body" the guitar (which is usually 6 to 8). Before proceeding, you may wish to examine the entire guitar very closely for any defects or unfilled grain that may have been overlooked previously. A little pumice and alcohol will take care of the unfilled grain. Remember, it is never too late to pumice. If the defects can be taken care of by a light sanding, use only 400 grit wet and dry sandpaper with oil as a lubricant. At this stage of finishing, in areas where there are "sink-outs", nicks and dents will tend to show where they previously were not apparent. This is the time to take care of and remedy any trouble spots that are visible. Any sink-outs, pin holes, or nicks can be filled using SuperGlue. First clean the area with naphtha, apply the glue and sand with 400 grit wet or dry sandpaper using oil as a lubricant. Now remove any excess pumice that may be left on the surfaces of the guitar using alcohol and a new muneca cover. The new muneca cover, along with alcohol, will tend to collect excess pumice. Now that we're satisfied with our inspection, lets begin "bodying" the guitar with shellac.

BODYING

Bodying is the process of applying shellac in many thin applications until a sufficient thickness is achieved. The body is sufficient when it can be sanded level with very fine sandpaper without burning-through to wood. Hundreds of passes of the muneca will be required, though individual layers are not the result. All the passes merge into one amorphous "sheet". Downward pressure of the muneca is critical for achieving a good degree of hardness of the final finish. We will be using a full 2-pound cut for the first 6 to 8 (body) sessions. Since we will not be too concerned about how smooth the body sessions go on, our efforts will be to build up the base finish as rapidly as we can. Later we will "level" the body coats to a perfectly smooth surface. Remember that we have already mixed a 2 pound cut of shellac and should be ready to proceed. The object of bodying is to build up enough finish on the instrument to allow it to be sanded level with fine sandpaper.

Glide the muneca onto the surface and move it in circular or oval patterns that overlap

Lets start by first installing a new muneca cover. As a matter of fact, you should cut a number of 4" x 4" squares of t-shirt material for muneca covers to have on hand as we proceed If at all possible find some well worn and laundered t-shirts. They tend to be softer than new material. Now add about 8 drops of 2 pound cut shellac. To this, add about 6 drops of alcohol. After a while you will be able to accurately estimate the amounts without counting drops. Finally add a drop of olive oil. Just wet the tip of your finger with oil and rub onto the bottom of the muneca. Smack the now loaded muneca against the back of your hand (several times) to distribute the shellac. Why the back of the hand? You will want to have a clean left palm to hold the guitar tightly while you work. The most difficult part of French polishing to master is in knowing when you have the muneca properly loaded. A good gauge is to use a piece of folded typing paper placed next to your work. When you load the muneca, smack against your hand several times and then blot against the paper. If you have added too much mix, the muneca will be too wet and the blot will also appear wet. If the mix is too little, no blot will show. If you have the correct amount, the blot will appear as many individual, separated spots on the paper. Another positive indicator of a properly loaded muneca is the famous "cloud" that is left behind the muneca as it lays on the shellac. This cloud is much like the cloud that your windshield wipers leave when there is oil on the windshield- appearing and disappearing as the wipers work back and forth.

"Pulling-over" the surface using long, straight strokes. Note that the finish is building nicely. Also not the small amount of oil on the surface- indicated by the arrow.

When the blot test shows that you have the right amount of mix, glide the muneca onto the surface of the guitar, using circular strokes, starting with the back (why the back? It is the easiest surface of the instrument to start with. It is relatively flat and has no obstructions or corners) Watch for the cloud or film of shellac left behind the muneca. Always glide onto and off of the surface of the instrument to prevent the muneca from sticking. NEVER STOP MOVING THE MUNECA WHEN IT IS IN CONTACT WITH THE INSTRUMENT. If you stop the muneca on the surface it will stick and damage the finish where you stop. Press firmly and use circular (or oval) and overlapping strokes as you cover about 13 of the back of the guitar. Move the muneca in patterns that will insure coverage of the entire surface. Be very methodical as you work. Be certain that you are getting even coverage over the area that you are working on.

Always blot the newly charged muneca on paper prior to contacting the instrument. This will help prevent damage due to an overly wet muneca.

Edges often get too little attention. Pay particular attention to all edges and "difficult" areas like the neck/body joint and the edge of the fingerboard. The cloud, or vapor trail of shellac left behind the muneca, will appear only if the shellac is going on properly. It will appear and disappear behind the muneca as you work. With a little practice, loading the muneca and applying shellac will become fairly routine. The loaded muneca should do about 13 of the back of the guitar. Reload your muneca as you complete each half. Early on you will need to reload more often- you will notice as you go along that each loading will cover more area. When you complete both halves, reload and work the back edges of the guitar. While working the edges hold the muneca at a 45 degree angle against the corners of the guitar and follow the contour of the guitar. When you have covered the entire back of the guitar, recharge your muneca, and use straight passes from one end of the guitar to the other. When you use these straight firm strokes it will help keep your work even. When you have completed the straight line passes, change back to the circular patterns and continue bodying. These straight strokes followed by circular strokes are called "pulling over". The straight line pattern tends to flatten out the marks left by the muneca during the circular passes and if your pressure is firm enough will result in a harder smoother body. Do not use too much oil. A single drop is all that is necessary when you load the muneca. Add additional oil, though, if you note the muneca sticking. Remember, the edges are often over looked and should be treated with special attention. Give the edges additional attention by reloading your muneca and carefully bodying the last 2 inches around the edges of the guitar. If everything is going well, you should be able to see a building of the shellac at this point. You should body the back at least twice before this first session is complete.

No, this is not the result of consuming too much ethanol during polishing. This represents a method of changing directions without stopping or lifting the muneca.

After completing the first session on the back, we will "stiff" off the shellac that we have just applied. This is done after each bodying session to remove oil and to reduce ridging from the muneca. "Stiffing" is done only with alcohol and maybe a drop or two of shellac added to the muneca. Add a few drops of alcohol to the bottom of the muneca and glide onto the guitar starting in the center. Again, watch for the tell-tale cloud! Press firmly and stroke in one direction from the heel of the guitar to the tail. Work your way systematically from the center of the guitar to the outside edges of the guitar gradually adding a little more pressure as the muneca runs dry. You can tell by observing the trail behind the muneca as the muneca get dryer. Load the muneca only with alcohol and one or two drops of shellac each time the muneca runs dry. You may not have to add oil during stiffing. There should be enough oil already in the muneca to complete the stiffing process. You can also use circular or oval strokes for stiffing. Do this if there are particular trouble spots or areas that need more attention. Use less pressure when the muneca is wetter and more pressure as it runs dry. During stiffing you will want to really exert pressure as the muneca is somewhat dry (but not totally dry). A lot gets done during bodying and stiffing during that critical point where the muneca has just the right amount of wetness to allow you to really push. Keep in mind, though that the guitar is fragile and don't push so hard as to cause damage. It is very important that the muneca be blotted each time it is loaded. Do not contact the guitar with the muneca unless you have blotted it and are certain it is not too wet. Now that the guitar has been stiffed off, the first session on the back of the guitar is complete. Turn the guitar on its side and reload the muneca with shellac, alcohol, and another drop of oil. With small circular motions, starting at the tail, work all the way to the heel of the guitar. When you get to the heel, squeeze the muneca so that it has a sharp edge and press firmly into the joint with each circular pass. Switch to a flat folded cloth and load with shellac, alcohol, and a drop of oil just as you would the muneca. With small circular motions rub the folded pad (from now on, just called a "pad") along the guitar side right into the neck joint. Repeat the process from the neck side of the joint. Use the blot test for the folded cloth the same as you would with the muneca. If the cloth is too wet it will not lay on shellac. Instead, it will actually tend to remove any previously applied shellac. Remember, look for the telltale cloud! Now, with a recharged muneca, go from circular motions to straight line passes from the heel toward the tail systematically, assuring even coverage. You should cover the sides of the guitar at least twice before stiffing. Start on the outer edge and at the tail of the guitar. Move the muneca in a straight line to the heel. When you get to the heel, do not stop the muneca. Return to the tail by looping around to the other edge of the guitar and then going to the tail. Repeat until you get to the middle of the side. Never stop the muneca. Always use a pattern that will allow you to change directions without stopping. Next, stiff off the side of the guitar just as we did on the back. Use only alcohol and straight strokes. Reload when you lose the cloud and add more pressure as the muneca starts to run dryer. Repeat this over and over until the side is entirely covered. You will probably want to do the top next so you can avoid turning the guitar onto the newly done side. This will give it some time to harden a bit and avoid damage to your new work. The top plate or soundboard is finished exactly the same way as the back and sides of the guitar except that it is not pumiced. The muneca is charged with shellac, alcohol, and a drop of oil, and with circular motions press firmly applying the shellac. If the bridge is installed, the top will be a more difficult to French polish. Many luthiers prefer to install the bridge after the guitar is finished in favor of an easier and better finish. Some luthiers like to install the bridge and string the instrument before the guitar is finished in order to provide any additional modifications to the thickness of the soundboard if necessary. If you prefer to install the bridge first, you may treat the bridge area the same as the neck joint. Use small circular motions up to the bridge and then, with your loaded and folded cloth pad, press firmly into the joint and wipe with a straight line along the full length of the bridge being certain that the joint is well covered. This takes practice, but after a few attempts, it should become easier. You will also use this same technique at the finger board/sound board joints. The neck is bodied exactly the same way as the back and sides. Go over it at least two times using small circular patterns, then in a straight line. Then as always, stiff off in a straight line.

The arrows indicate how the fingerboard or other obstruction is dealt with. Overlapping ovals are made that run up against the edge of the fingerboard.

The string slots of the classical guitar headpiece can be painted with shellac using a small camel-hair painters brush. The head slots can also be finished using a folded cloth, loaded with shellac, alcohol, and a very small drop of oil the same way as you would finish the heel joint. After a few sessions, the slots can be sanded smooth and a final finish layer applied. Another way is the "shoe-shine" method. Fold a piece of t-shirt material into a long, folded piece about 5 inches long and 1 inch wide. It should contain about 4 layers. Load all but the last inch of each end and blot it. Now use "shoe-shine" strokes to body the slots and crest of the head. This may leave a tiny ridge of shellac on the flat surfaces and these will need to be removed by leveling prior to continuing. Eugene Clark always admonishes his students to learn to form the muneca to the shape of the corner to access these difficult areas. This takes practice but once learned becomes second nature. Again, use circular patterns and then stiff off using straight passes. This will help keep the bodying even. The very nature of the small area of the head cap can make it very difficult to French polish. If your head piece is intricate with "V" cuts and complex shapes you will want to use your folded cloth in these areas. Do the machine slots first with the folded cloth then switch to the muneca for the flat areas. Any spillovers from the machine slots will be smoothed out when you change to the muneca. Running the muneca a bit dryer seems to help build the finish a bit faster. Be certain to press firmly in order to amalgamate each layer of shellac. The muneca can be obstructed by the machine slots and the nut slot and can cause the muneca to remove as much shellac as it puts on, so do not dwell on a single small area. Keep moving the muneca over and over the head piece until you see the shellac starting to build evenly on the entire surface. You may want to make a smaller muneca and use smaller circular patterns for the head piece. You can also try short deliberate strokes in much the same way as you would shine your shoes. Glide on and off many times until you see a buildup of finish. This should finish our first bodying session. The guitar should be left to "gas out" for several hours between each session.

Spiriting

After the guitar "gases out" for about an hour, you are ready to "spirit off" the guitar. Spiriting is the procedure used to remove the excess oil that has accumulated on top of the guitar's finish.

Spirit the surface using long, straight strokes. Use less pressure when the muneca is wetter and more pressure when it is relatively dry.

Time and pressure of the muneca has allowed the oil to permeate to the surface. We will want to remove the excess oil to prepare for the next bodying session. Spiriting is done in the exact same way as stiffing. In fact, there is really no difference between the two except for the reason you are doing it. A small amount of alcohol is loaded in the muneca and, with straight even strokes and firm pressure, go from one end of the guitar to the other. Use overlapping strokes, covering the entire surface of the guitar. There will be a very small amount of shellac left in the muneca which will guarantee that we will not be removing any shellac during the spiriting. After spiriting the entire guitar we are ready for the next bodying session. Even though the shellac is almost dry to the touch as it is being applied, it is advisable to let it continue to harden

During most French-polishing processes "reading" reflections can be a valuable method of evaluating your progress.

before more finish is applied. If too much finish is applied in a short period of time without allowing it to harden there is a danger of the finish "crazing". Crazing is a term given to a finish that has microscopic cracks in the surface. This occurs when solvents get trapped in the underlayer of a finish. The top layer, when exposed to air, will harden faster than the underlayer. When the solvents in the underlayers try to gas out, the top layer cracks as it shrinks. Crazing will also occur if the top layer is not properly amalgamated with the previous layers. This is why it is very important to press firmly on the muneca as you polish. French-polish will not craze if properly applied. After completing the first body session and the guitar's surface has been spirited off, look over the entire guitar for areas that may not have all of the grain filled. With alcohol and a little pumice, go over these areas again until they are filled. It is never too late to fill overlooked places that might have been missed- it just gets more difficult to fill pores as the finish builds.

Review

Now, lets review the bodying procedure . . .

1. Load your muneca with alcohol, shellac, and a single drop of oil. If your muneca is new you should wet it with at least 10 drops of alcohol for the first loading. Once the muneca is used, 6 to 8 drops of drops of shellac to five or six drops of alcohol will be sufficient to load the muneca from then on.
2. Smack the loaded muneca against the back of your hand to help distribute the shellac/alcohol mix. Use a sheet of typing paper to blot the muneca. A wet blot means too much mixture. No blot at all means it's too dry. A water mark print means that the muneca is correctly loaded.
3. Always glide on and off the guitar. Use rotating strokes, never stopping the muneca. Doing so will damage the finish where you stop.
4. Be methodical. Mentally divide the guitar surfaces in sections and do each section, one at a time, assuring even coverage. Apply shellac to the surface using circular overlapping strokes followed by long straight strokes pulling over the shellac. Pressure is very, very important. In general, use low pressure when the muneca is wetter and more pressure when the muneca is drier.
5. Watch for the telltale cloud behind the muneca! No cloud means that no shellac is going on to the guitar.
6. Use a paper towel or dry rag to blot excess moisture from the muneca. A muneca that is too wet will damage the instrument.
7. Use only alcohol while stiffing off the surface. The residual shellac in the muneca will assure that no shellac is being removed during stiffing.
8. Stiff the guitar in one direction. From the heel to the tail, start from the middle and work to the edges. When stiffing the sides, start at an edge and work to the middle.
9. Develop a technique that will allow you to change directions without stopping the muneca. Circular and figure 8 patterns followed by long straight strokes are used by experts.
10. Pay close attention to the edges and the corners of the guitar. It is natural to neglect the edges. Always treat the edges as separate surfaces. This will assure that the finish on the edges will not be too thin
11. Remember, use the oil sparingly. It is not necessary to add oil each time that you recharge the muneca. Use oil only when the muneca begins to drag or has a tendency to stick
12. In most cases, twice over the guitar using circular patterns, once using straight passes, and stiffing between bodying is considered a session. Remember, the muneca is gliding over the surfaces of the guitar many times as you work methodically in an area. In actuality, you have (or should have) covered every square inch of the guitar many times during each session.
13. Look over the guitar very carefully and re-pumice areas that may have been missed.
14. Spirit off the entire guitar using only alcohol added to the muneca using firm even strokes.
15. Continue to body for at least 4 more sessions
    
    

    Glazing

    
    Glazing is different from that of bodying the guitar by two major distinctions. First, we will use a very thin cut of shellac instead of the 2 pound cut that we have used up until now. Second, we will apply the shellac without using more straight patterns and fewer circular patterns. We will apply the shellac almost exactly the same way as we stiff the guitar. That is, we will start in the middle of the back of the guitar and apply the shellac mixture in a straight line from the heel to the tail. Circular patterns are used less often and are a method to correct problem areas. The object of glazing is simply to fill scratches left by the final leveling (sanding). Lets proceed as follows . . . You can make the thin glazing cut of shellac by simply adding several parts of alcohol to 1 part of shellac that you have been using up until now. Install a clean muneca cover and add a few drops (about 3 or 4 drops) of the 2 pound shellac. Add an equal amount of alcohol to the muneca and a drop of olive oil. Again as always, smack against the back of your hand to distribute the mix. Now, in a straight line press the muneca firmly starting from the heel and go to the tail of the guitar. Remember to glide on and off the guitar.

    Having adequate light will greatly help in gauging your progress.

    Repeat this pattern working from the middle to the edges of the guitar always watching for the cloud. Repeat this on the top, sides, and neck of the guitar. If you discover any defects while glazing the guitar use a very fine 1200 grit wet or dry sandpaper to level the area and continue to glaze the guitar. Remember to glaze the corners of the guitar and take extra care around the perimeter. This glazing procedure serves three purposes. First, it tends to smooth any ridging while filling the micro-scratches left from the final leveling. Second, the very thin cut of shellac tends to polish the instrument to a higher gloss while adding additional shellac to the guitar. Third, since more pressure is used, it tends to harden the finish. Many expert French polishers will add additional body coats after the final leveling and then use a liquid abrasive/polishing compound in place of using the glaze coat method that we use. You do, however, run the risk of actually polishing through the finish to the wood. An abrasive such as automotive rubbing compound will remove the very thin shellac finish. We have tried both methods and agree that the glazing method leaves a much richer and deeper finish without the risk of ruining a great deal of work. Once the glazing procedure is completed, inspect the work to locate any dull areas or defects. Lightly sand defects with 1200 grit wet or dry sandpaper and add additional glaze coats to the entire area. Dull areas are probably a result of the finish being too thin or of scratches not fully filled (glazed). If you discover a defect in the side of the guitar, sand and re-glaze the entire side. The same should be done on the top, back, neck and any other area that requires attention. When the final glaze coats are dry (about 4 days) we can now polish out the guitar. Polishing This is the simplest part of French polishing. First, go over the entire instrument with Meguiar's #7 Show Car glaze. Once again, if you discover a thin or dull area, add additional glaze coats. You will need to wait at least two days after any glazing process before you can use the Meguiar's and complete the project.

    Again, good light is a must. Note the smears of oil on the surface that is being glazed. The Meguiar's #7 will remove this residue easily.

    If you discover a slightly dull area or tiny scratch at during the #7 process you can attempt to correct the problem with Meguiar's #9 Swirl Remover. Be careful since this product contains a fine abrasive. The idea is to polish out a defect rather than fill it with more glaze sessions. This will only work if there is enough finish present to allow for abrasive polishing. Keep in mind that many times dull areas are a result of the finish being too thin. Abrasive polishing will only worsen this type of problem. On the other hand- a thin, dull area will need to be re-glazed with more sessions anyway so the abrasive polishing with Meguiar's #9 may be worth a try.

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