What tool to drill 4" circular hole ?

[capricorn]

What tool to drill 4\" circular hole ?

Hi All,

I need to drill a 4" diameter circular hole in a wooden bulkhead (in order to flush mount my ICS Navtex).

What tool should I use ? Biggest drill mounted hole saw I can find is 89mmwhaich ain't big enough. !

Hole will be visible other side of bulkhead so the usual bodge I might attempt with my jugsaw won't be good enough.

Thanks once again !

 

[Skysail]

Re: What tool to drill 4\" circular hole ?

I would try looking again for a 4in hole saw; we have recently cut a 5in dia hole in a locker to get at a stanchion base. Can't think of anything else that would do it. Maybe a tool hire shop?

 

[Marsupial]

Re: What tool to drill 4\" circular hole ?

Try a tank cutter, they are made for making round holes up to 6" in dia in galvanised tanks but you could use it on wood with no problems. Normaly mounted in a brace - not a power tool!

Monument is the brand name on mine.

 

[LittleShip]

Re: What tool to drill 4\" circular hole ?

Try these

http://www.tooled-up.com/Product.asp?PID=9063

Please dont use a tank cutter its not design for what you want to do??

 

[Wiggo]

Re: What tool to drill 4\" circular hole ?

Try an electrical factors. Our local lot is City Electrical Factors, and they have huge hole saws available.

 

[AndrewB]

Re: What tool to drill 4\" circular hole ?

As others say, a 4" diameter drill-mounted hole saw really should cause no problems - fairly certain I saw one in B&Q last weekend.

As you want it to look good from both sides, if possible drill in from both ends and meet in the middle, specially with plywood. Maybe there are other ways to stop the exit hole from splintering, but if so they don't work for me.

 

[ashanta]

Re: What tool to drill 4\" circular hole ?

Have you thought of using a pad saw or coping saw following the circle drawn out from a compass?
The finish can be much better than using a power tool or jig saw.

Regards.

peter.

 

[discovery2]

Re: What tool to drill 4\" circular hole ?

Ask a signwriter (or some locksmiths) to make you a plate in plastic laminate sheet (the sort that name plates are made from for doors in offices etc.) with a 4" hole. The outside shape can be any you choose, as can be the colour!

Cut the hole through the bulkhead with a jigsaw, and use the laminate plate to neatly mask the internal face. To avoid unsightly screws, fix the plate with double sided tape.

I have used this arrangement for a facia around a VHF radio. The radio was rectangular with curved sides and the fascia fitted perfectly.

Hope this helps. Send me a pm and I may be able to find a picture if this helps.

Good luck.
David.

 

[gorb]

Re: What tool to drill 4\" circular hole ?

Not really a problem. Screwfix do a 102mm hole saw for £8. You would need an arbor to go with it - another £4 or so from Screwfix.

 

[starboard]

Re: What tool to drill 4\" circular hole ?

Be carefull if you use the 102mm hole saw. After drilling the pilot hole for arbour, replace drill bit in arbour with metal rod of same dia as arbor drill but about 150mm long. This will act as guide pin for hole saw and if saw kicks back which it will it will stop the drill jumping out of the hole and running across bulkhead and causing damage......just as I did when cutting hole out for stereo speakers!!!!!

Good luck

Paul.

 

[Talbot]

Re: What tool to drill 4\" circular hole ?

As has already been said - screwfix for the 102mm bi-metallic hole saw plus the appropriate arbor. Make sure you use a decent electric drill - burnt my old one out cutting all the holes for eberspacher piping.

 

[tome]

Re: What tool to drill 4\" circular hole ?

I bought one from B&Q when I mounted my ICS Nav 6 plus.

 

[Benbow]

Re: What tool to drill 4\" circular hole ?

Exactly - What tool to drill 4" circular hole ? - a 4" circular hole cutter.

Why use anything else?

 

[TFJ]

Re: What tool to drill 4\" circular hole ?

Serves you right, whats all this about nancy's having ovens. you wait until you get hungry again!!
Terry

 

[TrueBlue]

Re: What tool to drill 4\" circular hole ?

You are supposed to drill the hole SLOWLY - max rpm 50 -70. Nobody - including me ever does, but if you are slow and gentle with the pressure, it shouldn't cook the drill. a half inch chuck masonry type should do.

 

[catskipper]

Re: What tool to drill 4\" circular hole ?

After just scoring the 4" circle with the blade of the saw, drill a 1/2" hole or two inside but just touching the cut line. The improvement in cutting from the hole clearing chips is monumental.

Scott

 

[pappaecho]

Re: What tool to drill 4\" circular hole ?

If you look in the Screwfix catalogue, you will find a tool which is designed for cutting holes in plywood, plasterboard etc, which is adjustable, from about 2 inches to nearly 5 inches. It has a central drill hole and a sliding chisel shaped tungsten carbide scribe which cuts a nice neat hole in plastics, wood etc, but not steel or aluminium. Well worth the money as it cuts almost any round hole that you will need on a boat