How To Drill A Hole In Opal

Obrada...

To drill a hole in Opal is not as simple as it sounds. We find many people buy Opal or Gemstones and try to drill a hole in it and don’t succeed. This can be very frustrating if the following procedure is not followed.

Here is a home made version made out in the opal fields Winton Queensland for drilling holes in boulder opals.

Its a dremel drill set up on a hand press shaft so it can be levered up or down. On the base he has set up adjustable drill shank to hold the bottom drill. This is a great idea as if anyone has tried to drill hole it is hard to get the holes to match up.

As if you try and drill all the way though the opal will chip at the end so this system is easy to make at home and to drill holes both ends of the opal and thy will match perfectly.

What tools do I need to Drill a Hole In Opal?

Diamond tip drills are suitable for drilling small quantities of Opals. These drill bits have been tipped with diamonds of different grades and shapes can be round, arrow pointed, long shape or hollow point. 120 grit is suitable for drilling holes.

These drill bits can be attached to any standard home drill or dremel drill but if the drill speed is set on high speed the diamonds will burn off in a matter of seconds. This happens frequently as there is incredible heat when a diamond drill bit touches the stone and it needs constant water on the stone when you drill. The drill must be on slow speed.

Standard home drill attachments that hold a drill are suitable but you will need a block to hold the Opal stable for drilling.

How to Drill A Hole In Opal

Drill a hole only half way through the stone. To start the hole tilt the drill and slowly with no force go to vertical if the drill is hand held. Keep removing the drill bit from the hole to clean out excess material and this allows water to wash out the hole and keep the drill from over heating. Do not use pressure to drill the hole.
Then turn the stone and drilled in from the other side so that the join is in the middle of the Opal. This is not easy to get exact but if you just drill all way through the Opal the drill will protrude on the other side and it will chip off edges and you will get an unsatisfactory finish.

Tips

Some commercial clamps are available that can turn the stone over 180 degrees
Wooden clamps can be made but it is important that you can turn the stone over and drill in exact hole so it is a clean join
Some cutters glue the Opal to bench so it is solid and then drill the hole
If your drill doesn’t have slow speed control keep the depth of drill so it is only slightly touching the stone
Slow speed slow work is best and plenty of water
Have a tube or hose connected to tap so water flow is constant
Set drill to slowest speed 7,000 to 10,000 rpm, this is slowest setting on dremel drills
Many large cutting factories have sonic drilling machines and these cut a hole by using a high frequency vibration. This is good for large commercial operators but are expensive and the cheap versions that we have seen do not give a satisfactory finish.

Making Opal Beads

Standard diamond tip wheels can be purchased that are 3-4 inches wide and these are curved so semi shaped beads are formed. Most are 100 to 140 grit.

To start shape the opal, mainly boulder opal or ironstone opal with colour bars to a rectangular shape are best. This long rectangular shape fits against the diamond tip curved wheel by another attachment that can be spinning or manually turned. The result will be uniform beads with two blocks on each end that can be sliced off with a saw blade.

Many cutters do get disappointed when making beads as rough is usually good to start but, most of the colour disappears when making beads so make sure you use Rough Opal that has colour veins running through them as they normally produce a good finished bead.

This bead cutting machine will make the boulder opal beads perfectly round. First the cuter has to cut the opal into a rectangular shape to make the bead. If you have ever tried to cut an opal into a round shape you will realize how difficult this is.

Tips

Matrix opal is also suitable for making beads
Black Opal is rarely used to make beads due to cost of Opal Rough

Polishing Tips

Rubber tips are also useful when making holes or polishing undulating surfaces on Opals.
Diamond impregnated rubber tips are ideal for finishing off edges after the hole is drilled or any undulating surface.
If you don’t have any rubber tips you can set up 1-2 inch diameter sandpaper on flexible rubber disk and use contact adhesive glue so sandpapers can be changed easily when worn.
No water is required.
You must have air suction to take air away and wear a mask whenever polishing with no water.
Vacuum cleaners can be used but it must have a strong suction and most household vacuums are not strong enough to take dust particles away from your face and mouth.
For the final polish you can use a lap and polishing power made into paste with concave and convex heads. They are good for difficult to get at spots especially on undulating Boulder Opal.
Opal books are also helpful in giving practical advice for Opal cutting and polishing. Example ‘Opal & How to work it’ by Frank Barnet.

I’m sure that you will agree that after you try and make some beads yourself you will appreciate why good quality Opal Beads are so expensive.

SHOP FOR OPALS

Boulder Opal

Izbušiti rupu u Opalu nije tako jednostavno kao što zvuči. Nalazimo da mnogi ljudi kupuju opal ili drago kamenje i pokušavaju izbušiti rupu u njima, ali ne uspijevaju. Ovo može biti vrlo frustrirajuće ako se ne slijedi sljedeći postupak.

Ovdje je domaća verzija izrađena u opalnim poljima Winton Queensland za bušenje rupa u kamenim opalima.

To je dremel bušilica postavljena na osovinu ručne preše tako da se može podići ili dolje. Na podnožje je postavio podesivi dršku svrdla za držanje donjeg svrdla. Ovo je sjajna ideja jer ako je itko pokušao izbušiti rupu, teško je postići da se rupe podudaraju.

Kao da pokušate izbušiti do kraja, iako će se opal okrhnuti na kraju, tako da je ovaj sustav lako napraviti kod kuće i izbušiti rupe, oba kraja opala i vaš će savršeno odgovarati.

Koji su mi alati potrebni za bušenje rupe u opalu?

Svrdla s dijamantnim vrhom prikladna su za bušenje malih količina Opala. Ova svrdla imaju dijamante različitih stupnjeva i oblika koji mogu biti okrugli, sa strelicom, dugački ili šuplji vrh. Granulacija 120 pogodna je za bušenje rupa.

Ova svrdla mogu se pričvrstiti na bilo koju standardnu kućnu bušilicu ili dremel bušilicu, ali ako je brzina bušilice postavljena na veliku brzinu, dijamanti će izgorjeti za nekoliko sekundi. To se često događa jer postoji nevjerojatna toplina kada dijamantno svrdlo dodirne kamen i potrebna mu je stalna voda na kamenu dok bušite. Bušilica mora biti na maloj brzini.

Prikladni su standardni kućni dodaci za bušilicu koji drže bušilicu, ali trebat će vam blok koji će Opal držati stabilnim za bušenje.

Kako izbušiti rupu u opalu

Izbušite rupu samo do pola puta kroz kamen. Za početak bušenja nagnite bušilicu i polako, bez sile, idite okomito ako je bušilica ručna. Nastavite uklanjati svrdlo iz rupe kako biste očistili višak materijala i to omogućuje vodi da ispere rupu i spriječi pregrijavanje svrdla. Ne koristite pritisak za bušenje rupe.
Zatim okrenite kamen i izbušite ga s druge strane tako da spoj bude u sredini Opala. To nije lako točno odrediti, ali ako samo probušite do kraja kroz Opal, svrdlo će stršati s druge strane i odlomit će rubove i dobit ćete nezadovoljavajuću završnu obradu.

Savjeti

Dostupne su neke komercijalne stezaljke koje mogu okrenuti kamen za više od 180 stupnjeva
Mogu se napraviti drvene stezaljke, ali je važno da možete okrenuti kamen i izbušiti točnu rupu kako bi spoj bio čist
Neki rezači zalijepe Opal za stol tako da bude čvrst, a zatim izbuše rupu
Ako vaša bušilica nema kontrolu male brzine, držite dubinu bušilice tako da samo malo dodiruje kamen
Spora brzina, spor rad je najbolji i puno vode
Priključite cijev ili crijevo na slavinu kako bi protok vode bio stalan
Postavite bušilicu na najmanju brzinu od 7.000 do 10.000 o/min, ovo je najsporija postavka na dremel bušilicama
Mnoge velike tvornice za rezanje imaju zvučne strojeve za bušenje i oni izrezuju rupu pomoću visokofrekventnih vibracija. Ovo je dobro za velike komercijalne operatere, ali je skupo, a jeftine verzije koje smo vidjeli ne daju zadovoljavajuću završnicu.

Izrada Opal perli

Mogu se kupiti standardni kotačići s dijamantnim vrhom koji su široki 3-4 inča i zakrivljeni su tako da se formiraju poluoblikovane perle. Većina je od 100 do 140 grita.

Za početak oblikovanja opala, uglavnom je najbolji opal u obliku gromade ili opal od željeznog kamena s trakama u boji u pravokutni oblik. Ovaj dugi pravokutni oblik pristaje uz zakrivljeni kotač s dijamantnim vrhom pomoću drugog dodatka koji se može okretati ili ručno okretati. Rezultat će biti jednolične perle s dva bloka na svakom kraju koji se mogu odrezati oštricom pile.

Mnogi se rezači razočaraju kada izrađuju perle jer je grubo obično dobro za početak, ali većina boje nestaje kada izrađuju perle pa se pobrinite da koristite grubi opal kroz koji prolaze vene boje jer obično daju dobru gotovu perlu.

Ovaj stroj za rezanje perli napravit će savršeno okrugle perle od opala. Najprije slatkiš mora izrezati opal u pravokutni oblik kako bi napravio perlu. Ako ste ikada pokušali izrezati opal u okrugli oblik, shvatit ćete koliko je to teško.

Savjeti

Matrix opal također je pogodan za izradu perli
Crni opal se rijetko koristi za izradu perli zbog cijene grubog opala

Savjeti za poliranje

Gumeni vrhovi također su korisni kod pravljenja rupa ili poliranja valovitih površina na Opalsima.
Gumeni vrhovi impregnirani dijamantima idealni su za završnu obradu rubova nakon bušenja rupe ili bilo koje valovite površine.
Ako nemate gumene vrhove, možete postaviti brusni papir promjera 1-2 inča na fleksibilnu gumenu ploču i koristiti kontaktno ljepljivo ljepilo tako da se brusni papiri mogu lako promijeniti kada se istroše.
Nije potrebna voda.
Morate imati usis zraka za odvođenje zraka i nositi masku kad god polirate bez vode.
Mogu se koristiti usisavači, ali oni moraju imati jako usisavanje, a većina kućnih usisavača nije dovoljno jaka da ukloni čestice prašine s vašeg lica i usta.
Za završno poliranje možete koristiti lap i snagu za poliranje izrađenu u pastu s konkavnim i konveksnim glavama. Dobre su za teško dostupna mjesta, posebno na valovitom Boulder Opalu.
Opal knjige su također korisne u davanju praktičnih savjeta za Opal rezanje i poliranje. Primjer "Opal & Kako to raditi" Franka Barneta.

Siguran sam da ćete se složiti da ćete, nakon što sami pokušate napraviti neke perle, shvatiti zašto su opalne perle dobre kvalitete tako skupe.