Tso plywood rau hauv pem teb ntoo nrog koj tus kheej tes: nta, technology thiab cov lus pom zoo

Cov txheej txheem:

Tso plywood rau hauv pem teb ntoo nrog koj tus kheej tes: nta, technology thiab cov lus pom zoo
Tso plywood rau hauv pem teb ntoo nrog koj tus kheej tes: nta, technology thiab cov lus pom zoo

Video: Tso plywood rau hauv pem teb ntoo nrog koj tus kheej tes: nta, technology thiab cov lus pom zoo

Video: Tso plywood rau hauv pem teb ntoo nrog koj tus kheej tes: nta, technology thiab cov lus pom zoo
Video: Tshuaj theem vim li cas thiaj tau nqi ?/ Siv kho mob dab tsi?/paris polyphylla use for? 2024, Hlis ntuj nqeg
Anonim

Ntau zaus, thaum lub sijhawm kho hauv tsev lossis chav tsev, nws tsis raug nquahu kom rhuav tshem cov ntoo qub, tab sis qhov saum npoo yuav tsum tau leveled thiaj li ua tau haujlwm ntxiv. Nyob rau hauv tas li ntawd, koj muaj peev xwm ua ib tug ntxhib plywood pem teb, yog li tsim ib tug zoo kawg nkaus tiaj tus. Plywood pem teb yog ruaj thiab resistant rau ntau yam deformations. Lub hauv paus plywood zoo meej rau kev ua tiav ntxiv, yog nws laminate, parquet lossis khoom ntoo. Lub hauv paus no muaj ntau lwm yam zoo. Cia peb saib yuav ua li cas plywood nteg raws li lub hauv paus ntxhib.

Khoom zoo

Cov ntawv Extruded yog cov khoom siv zoo heev rau kev ua haujlwm hauv pem teb. Cov ntawv yog pheej yig, lawv yooj yim thauj, nruab. Plywood yooj yim tshem tawm qhov siab me me sib txawv ntawm hauv pem teb. Plywood feem ntau yog pwUa ntej txhim kho parquet, laminate thiab lwm yam hauv pem teb tiav.

ua-nws-koj tus kheej plywood flooring
ua-nws-koj tus kheej plywood flooring

Cov ntawv txo lub sijhawm xav tau rau kev npaj ua ntej ua ntej txhim kho pem teb tiav. Plywood zoo tiv thaiv lub hauv qab ntawm cov txheej tiav los ntawm kev lwj - cov khoom muaj peev xwm "ua pa". Qhov no tuaj yeem siv tau thaum tsuas yog cov pob zeb ua pob zeb muaj nyob ua subfloor.

Plaub uas muaj qib nrog plywood pab tiv thaiv kev hnav lossis deformation ntawm linoleum, ntaub pua plag thiab lwm qhov chaw mos, yog li txuas lub neej hauv pem teb. Siv plywood, koj tuaj yeem tau txais ib qho chaw tiaj tiaj. Tus nqi ntawm kev tso plywood rau hauv pem teb yog tsawg heev, thiab tag nrho cov txheej txheem yog ua los ntawm tes.

Cov ntawv yog tus yam ntxwv los ntawm qhov hnyav, siab hardness, tsis kam mus rau ntau yam loads (xws li abrasion). Cov khoom siv tsis muaj ntxhiab tsw, muaj suab zoo heev thiab cov yam ntxwv ntawm cov cua sov. Plywood tsis cia cua sov los ntawm, tab sis khaws cia rau hauv. Cov nplooj ntawv raug txiav hauv qhov ntau thiab tsawg - qhov no tso cai rau koj kom txo tau cov pob qij txha hauv cov txheej txheem ntawm plywood. Cov nplooj ntawv yog polished ntawm lub Hoobkas - qhov no tiv thaiv kev swb ntawm plywood nws tus kheej thiab lwm yam ntaub ntawv uas tau muab tso rau ntawm lawv. Plywood kuj yog dej tsis huv, ua rau nws zoo tagnrho rau cov plag tsev hauv cov chaw ntub dej xws li chav dej, chav dej thiab chav ua noj.

Cov khoom siv hauv eco, nyab xeeb rau tib neeg, tsiaj thiab menyuam yaus. Ib qho txiaj ntsig tseem ceeb yogtus nqi pheej yig. Leveling pem teb nrog plywood yog qhov zoo tshaj plaws.

txheej txheem ntawm kev tso plywood yog qhov yooj yim, thiab qhov no cuam tshuam rau lub sijhawm ua haujlwm - lawv tsawg heev. Qhov no tuaj yeem piav qhia yooj yim los ntawm qhov tseeb tias cov khoom siv tuaj yeem ntsia tau rau ntawm txhua lub hauv paus.

Flaws

Cov khoom muaj qhov tsis zoo, tab sis tsis ntau heev. Plywood tsis ruaj khov rau hluav taws: nws yog ntoo. Qib ntawm kev nyab xeeb hluav taws yog tsawg heev. Tsis tas li, qhov tsis zoo tuaj yeem suav tias yog tus nqi thaum piv nrog cov chipboard zoo sib xws thiab fiberboard. Ib pem teb theem nrog plywood, tsawg kawg yog me ntsis, yuav ua rau kom qhov siab ntawm cov qauv kawg. Yog tias lub qab nthab hauv chav qis, ces qhov kev xaiv no zoo dua tsis txhob siv.

tso plywood rau hauv pem teb nrog koj lub cuab yeej
tso plywood rau hauv pem teb nrog koj lub cuab yeej

Daim ntawv twg xaiv rau hauv pem teb?

Tso plywood nrog koj tus kheej txhais tes yuav tsum xaiv cov ntaub ntawv zoo. Qhov tsim nyog plywood yog tus yuam sij rau kev ua tau zoo. Kev lag luam tsim nws hauv cov ntawv txheeb, thiab nws raug cais raws li cov txheej txheem hauv qab no. Cov no yog cov txheej txheem thiab muaj cov impregnations, hom plywood, tus naj npawb ntawm cov khaubncaws sab nraud povtseg nyob rau hauv daim ntawv, muaj kev kho deg, ya raws.

Yog tias ib feem ntawm cov qauv ua los ntawm cov plywood tau muab zais los ntawm kev pom, cov kws tshaj lij pom zoo kom xaiv cov kev xaiv dej noo-resistant ntawm qib thib ob lossis qib peb. Cov nplooj ntawv yuav tsum muaj lub thickness tsis pub tsawg tshaj kaum millimeters. Tab sis nws yog qhov zoo tshaj plaws los siv cov ntawv los ntawm 14 mus rau 22 millimeters thaum tso plywood hauv qab laminate. Cov ntaub ntawv nyias yuav tsis tuaj yeem tiv taus qhov hnyav. Cov ntawv tuab dua tsis yooj yim ua haujlwm nrog.

Yuav tsum muaj pes tsawg txheej ib daim ntawv?Nws tsis muaj teeb meem rau kev teeb tsa hauv pem teb. Cov kws tshaj lij pom zoo kom yuav plywood sanded ntawm ob sab.

About ntau yam thiab hom

Plywood yog tsim nyob rau hauv plaub qib. Cia wb mus saib lawv. Paub txog ntau yam yuav pab xaiv:

  • Cov khoom ntawm qib plaub muaj ntau yam tsis xws luag ntawm txheej. Qhov saum npoo yog ntxhib, muaj qhov los ntawm cov pob caus, vim cov khoom siv qis tshaj plaws yog siv rau kev tsim khoom.
  • Plywood ntawm qib peb yog qhov zoo dua. Muaj kev sib yuav tsawg dua ntawm nws qhov chaw, tab sis nws muaj.
  • Qib thib ob yog yam ntxwv los ntawm qhov muaj cov kab nrib pleb me me, tab sis qhov saum npoo ntawm cov plywood yog du.
  • Cov khoom zoo tshaj plaws yog qib thawj. Qhov no yog qhov kim tshaj plaws plywood. Cov nplooj ntawv tau ua tib zoo sanded ntawm txhua sab, thiab tsis muaj qhov tsis xws luag ntawm txhua qhov chaw.
tso plywood rau hauv pem teb los ntawm tes
tso plywood rau hauv pem teb los ntawm tes

Raws li txoj kev ua, plywood tuaj yeem yog sanded lossis unsanded. Rau kev tsim kho ntawm cov plag tsev ntxhib lossis qib uas twb muaj lawm, lawv tau txais cov khoom polished ntawm ib sab xwb.

Rau cov khoom siv rau kev tsim khoom

Plywood nplooj ntawv yog tsim los ntawm cov ntoo tawv thiab cov ntoo coniferous - feem ntau cov tuam ntxhab siv birch thiab ntoo thuv. Lub veneer yog tuav ua ke nrog ntuj los yog hluavtaws resins. Cov txheej saum toj kawg nkaus yog kho nrog cov tshuaj tiv thaiv dej.

Ntxiv rau kev faib los ntawm qib, plywood raug cais raws li qib ntawm kev tiv thaiv kom ya raws. Yog li, cov npe hauv qab no yog qhov txawv - FBA, FSF, FC.

Rau cov plag tsev hauvchav pw thiab lwm qhov chaw nyob uas cov av noo tsawg, koj tuaj yeem siv cov khoom ntawm FK thiab FBA hom. Lawv yog tsim los ntawm carbamide thiab albumin-casein kua nplaum. Plywood yog eco-phooj ywg thiab tib lub sijhawm tiv taus noo noo.

FSF yog qhov nyiam rau chav dej, chav ua noj, txoj hauv kev thiab muaj feem cuam tshuam hauv lwm chav uas cov av noo siab. Tom qab ntawd, tom qab theem hauv pem teb, tso cov vuas ntawm plywood rau hauv pem teb tuaj yeem nqa tau.

Yuav ua li cas npaj plywood?

Ua ntej pib ua haujlwm, qhuav cov khoom siv li 2-3 lub lis piam. Cov nplooj ntawv yuav tsum tau qhuav vertically. Nyob rau hauv cov ntaub ntawv no, qhov kub thiab txias nyob rau hauv lub chav tsev yuav tsum yog me ntsis siab dua chav tsev kub. Thaum ziab tiav lawm, cov nplooj ntawv raug kho nrog cov khoom siv tshuaj tua kab mob thiab chav tsev yog qhov cua zoo. Yog tias koj xav tau kom muaj zog ntawm cov nplooj ntawv, ces ob peb txheej ntawm acrylic kua roj vanish yog siv rau lawv.

Ob hnub ua ntej pib ua haujlwm nrog plywood, cov khoom raug coj mus rau hauv chav tsev uas yuav ua haujlwm.

Nyob plywood rau ntawm ib tug qub ntoo pem teb

Nyob rau hauv cov txheej txheem ntawm kev teeb tsa ntawm cov ntoo hauv pem teb, cov ntawv tuaj yeem kho tau ntau txoj hauv kev - nrog rau tus kheej tapping screws, ntawm cov kua rau tes, ntawm cov kua nplaum.

Thaum tso cov plywood rau cov kua nplaum, cov kua nplaum ua kua dej, cov kua nplaum ob, cov nplaum sib dhos, thiab cov bustilat yog siv. Tab sis nws yog qhov zoo dua los kho cov nplooj ntawv ntawm tus kheej tapping screws.

Cov cuab yeej thiab cov khoom siv

txhawm rau txhim kho cov ntawv plywood kom ua tiav, cov cuab yeej thiab cov khoom siv hauv qab no yuav tsum tau ua. Yog li, koj xav tau plywood nws tus kheej, jigsaw, kev tsim khoqib, daim kab xev ntsuas, cwj mem los yog cim. Kuj tseem muaj qhov xav tau rau lub tshuab grinder, cov menyuam, primer. Cov ntaub nplaum thiab cov khoom sib khi tau npaj.

ua haujlwm ua ntej

Hauv pem teb yog leveled nrog plywood nkaus xwb yog tias qhov siab sib txawv tsis ntau tshaj kaum millimeters. Hauv qhov no, koj yuav xav tau lub substrate uas them nyiaj rau qhov tsis sib xws, nrog rau cov nplaum nplaum rau cov khoom sib txuas.

Tom ntej no, nws yog ib qho tseem ceeb uas yuav tsum tau soj ntsuam qhov dav dav ntawm lub hauv pem teb qub. Yog hais tias muaj creaking floorboards, ces lawv muaj zog. Rotten ntsiab los yog damp - hloov. Tsis txhob sim kho lub floorboard uas tau raug tawm tsam los ntawm pwm los yog mildew.

Cov plag tsev tau ntxuav ntawm cov plua plav thiab av, lawv tau dhau ob zaug dhau ntawm qhov chaw nrog primer ntawm ntoo - qhov no yog qhov tsim nyog los ua kom adhesion. Tom ntej no, lub hauv paus yog qhuav rau li 16 teev.

Plywood yuav tsum tau txiav nyob rau hauv xws li ib txoj kev uas tus naj npawb ntawm cov pob qij txha yuav tsum tau kom tsawg kawg nkaus, coj mus rau hauv tus account damper pob qij txha ntawm nplooj ntawv ntawm 3-4 hli, thiab kuj 8-10 hli ntawm daim ntawv thiab phab ntsa. Qhov no yuav zam tau qhov o ntawm cov nplooj ntawv yav tom ntej. Nyob rau hauv tus txheej txheem ntawm kev khiav hauj lwm thiab kub hloov, lub workpiece yuav nce.

Sawing yog nqa tawm siv lub jigsaw. Nws raug nquahu kom ua tib zoo tshuaj xyuas qhov kawg ntawm plywood blanks - yuav tsum tsis txhob muaj delaminations. Ntawm thaj chaw loj, plywood raug txiav rau hauv ib lub xwmfab ntawm 50x50 cm lossis ntau dua. Cov txheej txheem no yuav raug ntsuas hauv pem teb thiab tshem tawm cov teeb meem kev teeb tsa. Cov sawn blanks yog suav nrog thiab cov layout yog tsim los ntawm cov lejblanks rau pem teb.

txheej txheem Styling

Muaj peculiarities nyob rau hauv lub installation txheej txheem. Yog tias tsim nyog, cov txheej txheej qub yog them nrog lub substrate qhov twg nws xav tau. Qhov rau fasteners tau ua ua ntej nrog tus kheej tapping screws, thiab tom qab ntawd lawv tau ntxiv countersinked. Lub taub hau ntawm tus kheej tapping ntsia hlau yuav tsum tau muab tso rau hauv daim ntawv.

Tso plywood nyob rau hauv linoleum los yog lwm yam txheej yog nqa tawm los ntawm niches, podiums, ntau ledges. Tom qab ntawd cov nplooj ntawv tau npaj los ntawm nruab nrab mus rau cov npoo nrog kev hloov pauv zoo li brickwork. Txhua qhov tawg thiab qhov khoob yog ntim nrog kua nplaum.

Ntawm rau ntawm lub cav

Yog tias qhov siab sib txawv ntawm lub hauv paus yog ntau tshaj 1 centimeter, ces nws raug nquahu kom nteg plywood rau ntawm cov laug cam lossis cov cav ntoo. Cov tom kawg tuaj yeem ntsia tau rau hauv pem teb qub, tab sis koj yuav tsum paub tseeb tias txhua yam nyob rau hauv kev txiav txim zoo nyob rau hauv nws.

Lub hauv pem teb qub yog ntxuav cov khib nyiab thiab hmoov av. Nyob rau hauv rooj plaub no, koj yuav tsum tau them sai sai rau qhov sib txawv ntawm cov floorboards. Yog hais tias cov kab nrib pleb loj, ces lawv tau ntim nrog kua nplaum los yog sealant. Nyob rau tib lub sijhawm, cov ntawv plywood tab tom npaj - cov khoom yog sawn, cov cim ua rau ntawm daim ntawv, cov ntsiab lus raug suav.

Lags yog cov lus qhia rau qib hauv pem teb. Cov no yog cov slats, qhov ntev yog kwv yees li 1.5-2 meters, qhov hla ntawm lub rooj tsavxwm yog 40x15 millimeters. Cov cav yog txuas rau hauv pem teb nrog dowels los yog tus kheej tapping screws. Lawv tau teem kom lawv cov ciam teb sab sauv muab ib lub dav hlau, thiab cov slats muab ib lub crate. Yuav muaj qhov chaw nruab nrab ntawm cov lus qhia - nws tau ntim nrog cov khoom siv suab nrov. Koj tseem tuaj yeem zais kev sib txuas lus nyob ntawd.

Ntxiv mus, cov plywood squares yog mounted raws li daim duab. Kev kho yog ua tiavntawm kua ntsia hlau, tus kheej tapping ntsia hlau los yog kua nplaum.

Cov haujlwm kawg

Txawm hais tias lub cuab yeej, tso plywood rau hauv pem teb nrog koj tus kheej txhais tes kuj txhais tau tias ua haujlwm tiav. Nws los mus ua cov pob qij txha ntawm cov nplooj ntawv nrog emery kom du tawm irregularities. Tom qab xuab zeb, tag nrho saum npoo yog varnished.

Mounting plywood on a coupler

Peb tau saib cov yam ntxwv ntawm mounting rau hauv pem teb ntoo. Tab sis nyob rau hauv feem ntau cov chav tsev cov plag tsev yog pob zeb. Cia peb saib cov yam ntxwv ntawm kev tso plywood hauv qab screed.

Ua ntej pib ua haujlwm, qhov saum npoo kuj raug ntxuav kom huv si. Nws yuav zoo heev yog tias qhov chaw ntxuav tsis yog nrog tus txhuam hniav, tab sis nrog lub tshuab nqus tsev. Cov khib nyiab, xuab zeb, nrog rau cov plua plav - tag nrho cov no yuav cuam tshuam qhov adhesion ntawm cov nplaum rau hauv pem teb. Tsis tas li ntawd, los ntawm cov kua nplaum, qhov tsis sib xws hauv daim ntawv ntawm cov khib nyiab yuav twb tshwm sim ntawm cov av tiav.

Tom qab ntawd tag nrho saum npoo ntawm cov screed yog them nrog nkag mus rau primers. Cov kua nplaum yog siv nrog ib daim duab spatula, thiab tom qab ntawd txiav plywood yog nteg los ntawm cov lej. Yuav kom plywood lo zoo rau hauv pem teb, nws yog attracted nrog ib tug dowel-ntsia hlau. Siv lub perforator, ib lub qhov yog ua nyob rau hauv lub plywood thiab hauv pem teb, thiab ces ib tug dowel yog hammered rau hauv lub qhov nrog ib tug rauj.

Plywood nteg thev naus laus zis txhais tau tias cov nplooj ntawv tau muab tso rau ntawm qhov deb ntawm ib leeg. Yog li, nruab nrab ntawm lawv nws yog ib qho tsim nyog yuav tsum tau thim rov qab txog 4 millimeters, thiab los ntawm phab ntsa - 1 centimeter. Qhov no yog tsim nyog los them rau qhov khoob vim hloov pauv hauv cov duab geometry ntawm plywood vim muaj kev hloov pauv ntawm kev nyab xeeb lossis av noo.

ua-nws-koj tus kheej plywood nteg ntaus ntawv
ua-nws-koj tus kheej plywood nteg ntaus ntawv

Yog hais tias ntawm cov khoom sib caismuaj irregularities, ces lawv raug tshem tawm nrog ib tug sib tsoo tshuab. Qhov khoob ntawm cov nplooj ntawv yog ntim nrog kua nplaum. Kev tawg tuaj yeem raug kaw nrog gypsum-based finishing plaster. Tom ntej no, cov seams yog rubbed nrog ib tug tshwj xeeb grout mesh. Kev tsis sib xws ntawm plywood kuj tseem npog nrog plaster.

Ntxiv mus, txhua txoj hlua ntawm plaster yog glued nrog ib daim kab xev tshwj xeeb ntxiv. Tom qab ntawd koj tuaj yeem ua tiav mus rau qhov ua tiav ntawm lub hauv paus.

Cov lus pom zoo rau cov ntawv txuas rau ntawm pob zeb

Koj tuaj yeem muab cov plywood waterproof hom FK rau ntawm screed. Nws muaj cov ntoo veneer, uas txhais tau hais tias tsis muaj teeb meem phenol siv hauv kev tsim khoom. Cov plywood no tau siv dav hauv thaj chaw nyob. Cov nplooj uas tsis muaj xuab zeb yuav tsum tau xuab zeb tom qab tso. Koj tuaj yeem muab plywood rau ntawm screed, uas tsuas yog ua tiav ntawm ib sab. Lub thickness yuav txawv ntawm 1.2 mus rau 1.5 centimeters.

plywood rau hauv pem teb ua-nws-koj tus kheej ntaus ntawv
plywood rau hauv pem teb ua-nws-koj tus kheej ntaus ntawv

Cov ntawv tau muab tso nrog qhov sib txawv kom tag nrho plaub lub seams tuaj yeem koom nrog hauv ib qho chaw. Tsis txhob hnov qab txog waterproofing - txheej yuav tsum tau muab tso rau ntawm lub screed ua ntej txhim kho plywood. Cov ntawv tau pom zoo kom kho nrog cov roj kom qhuav hauv ob txheej ua ntej tso.

Nws tsis yog ib txwm tsim nyog los txiav cov ntawv rau hauv me me - tshwj xeeb tshaj yog rau cov tsev nyob hauv nroog. Qhov no tsuas yog ntxiv ua haujlwm ntxiv xwb.

Plywood hauv qab linoleum

Qee tus kws tshaj lij pom zoo kom tsis txhob siv plywood rau linoleum, tab sis nrov OSB. Tab sis cov phiaj xwm tsis zoo txawm tias, nyob rau hauv qhov kev thauj khoom tas li, ib feem ntawm cov chips tuaj yeem tev tawm ntawm daim ntawv - qhov no yeej yuav cuam tshuam qhov sib npaug ntawm hauv pem teb. Chipboard thiab fiberboard kuj tsis haum. Plywood- qhov kev xaiv zoo tshaj plaws.

Nws yog qhov zoo tshaj plaws los yuav cov nplooj ntawv nrog lub thickness ntawm 12 millimeters lossis ntau dua. Rau lub tiaj tiaj tiaj tiaj, cov ntaub ntawv nyias txog li 8 millimeters tuab yog tsim nyog. Nrog rau qhov tshwj xeeb tsis sib xws, lawv tau cov plywood tuab ntawm 20 millimeters.

ua-nws-koj tus kheej hauv pem teb nteg ntaus ntawv
ua-nws-koj tus kheej hauv pem teb nteg ntaus ntawv

Cov txheej txheem ntawm kev ua haujlwm, yuav ua li cas nteg plywood rau hauv pem teb, nruab plywood pem teb - txhua yam tau piav qhia hauv qab no.

Nruab parquet thiab array ntawm plywood

Ntau tus neeg paub tseeb tias lub hauv paus ntxhib rau hauv pem teb parquet yog ib qho nyiaj pov tseg. Txawm li cas los xij, tsis yog. Cov kws tshaj lij nrog kev paub paub tseeb tias nrog kev pab ntawm plywood koj tuaj yeem tau txais txiaj ntsig zoo. Lub subfloor yuav ua kom lub hauv paus tiav los ntawm kev hnav sai.

Raws li rau cov cuab yeej ntawm kev tso parquet boards ntawm plywood, cov txheej txheem mus zoo dua yog tias lub hauv paus yog pob zeb. Ua ntej kev teeb tsa, nws yog ib qho tseem ceeb los txiav txim siab seb lub parquet pawg thawj coj yuav nyob li cas.

Tom ntej, cov ntawv plywood tau npaj - ib daim ntawv raug txiav rau hauv cov squares ntawm 50x50 centimeters. Nws yog qhov zoo tshaj plaws los xaiv plywood waterproof. Installation yog nqa tawm nrog los yog tsis muaj kua nplaum. Cov ntsiab lus tuaj yeem ua kom nrawm nrawm nrog qhov sib txawv them nyiaj. Tsis tas li ntawd, cov nplooj ntawv raug kho nrog cov fasteners tshwj xeeb. Lub thickness ntawm plywood yuav tsum yog 70 feem pua ntawm cov parquet thickness. Tsis tas li ntawd, tom qab cov kua nplaum tau qhuav, koj tuaj yeem txuas ntxiv nrog kev teeb tsa ntawm parquet board.

plywood tso
plywood tso

Tau ib lub rooj tsavxwm rau ntawm plywood txawv tsuas yog tias cov khoom ntoo yog cov khoom sib txawv me ntsis. Raws li kev teeb tsa ntawm plywood, cov txheej txheem zoo sib xws.

Zoo kawg

Yog li, peb tau saib yuav ua li cas nteg plywood rau hauv pem teb kom zoo. Nrog rau qhov kev ua haujlwm no, koj tuaj yeem yooj yim thiab nrawm rau theem ntawm qhov chaw thiab yuav luag tam sim ntawd pib txhim kho hauv pem teb npog. Feem ntau cov plywood yog siv nyob rau hauv thiaj li yuav nruab laminate boards.

Pom zoo: