How do I cut a 140mm circular hole through 5mm ply, without a jigsaw?

[Greenheart]

Suddenly realised I don't know how to cut large round holes for the inspection hatches in my replacement bulkhead.

The rims of the hatches will cover any rough edges, just as well because I don't much want to shell out on a jigsaw for this one simple job.

Is it a case of drilling lots of small holes in a circle?

 

[Hugh Foulis]

Stitch drilling. T
hats how I have done it in the days pre-jigsaw.

 

[johnphilip]

At £18.87 is a jigsaw such an extravagance?
http://www.toolstation.com/shop/Power+Tools/Jigsaws/d40/sd3251
I have not tried the jigsaw but at £26 their planer has proved excellent.
This one job will save a fiver's worth of frustration.

 

[steveallan]

buy or hire a hole cutter

Suddenly realised I don't know how to cut large round holes for the inspection hatches in my replacement bulkhead.

The rims of the hatches will cover any rough edges, just as well because I don't much want to shell out on a jigsaw for this one simple job.

Is it a case of drilling lots of small holes in a circle?

 

[Cloven]

buy or hire a hole cutter

http://www.ebay.co.uk/itm/HOLE-SAW-...BOR-EXTENSION-SHANK-PILOT-DRILL-/251323979953

 

[nigelmercier]

buy or hire a hole cutter

I use one of these for large holes: http://amzn.to/1lapqSX
For 140mm you may need a larger one: http://amzn.to/1iI5KIW

Cut half way from one side, then the other. Drill slowly.

 

[DanTribe]

A padsaw would do the job but is laborious and needs practice to get a reasonable fair cut.
A hole saw would give a neater job with less sweat.

 

[prv]

140mm holesaw.

Pete

 

[cliff]

140mm holesaw.

Pete

+1

 

[savageseadog]

140mm holesaw.

Pete

++1. Don't mess about, it might be possible to borrow one. It's safer using a hole saw as well as being neater, easier and quicker, there's less chance of accidentally cutting something that you shouldn't.

 

[Poignard]

Tank cutter

 

[Lakesailor]

Now is the time in your life to step up to jigsaw ownership.

 

[KellysEye]

I had one of these http://www.ebay.co.uk/bhp/drill-hole-cutter

 

[ghostlymoron]

I used one of those to cut a hole in bulkhead for my compass - it was completely bu33red after it. If you don't want to buy a jigsaw, stitch drill then pads and file but i would strongly recommend a jigsaw.

I use one of these for large holes: http://amzn.to/1lapqSX
For 140mm you may need a larger one: http://amzn.to/1iI5KIW

Cut half way from one side, then the other. Drill slowly.

 

[JumbleDuck]

Is it a case of drilling lots of small holes in a circle?

That's how I do it. A drill with a flap wheel smoothes it all nicely.

 

[philip_stevens]

http://www.toolstation.com/shop/Pow...stable+Hole+Cutter+40+300mm/d80/sd1400/p44999

View attachment 42449

40 - 300mm

 

[Brighterhope]

I would use a 140mm hole saw. This is one I saw on E bay and is of good quality. It will give you a good result.

http://www.ebay.co.uk/itm/Starrett-...Home_Garden_PowerTools_SM&hash=item51bd3dd3c8

 

[Rigger Mortice]

Drill the holes and sand/file to clean it up.
You'll have it done in less time than it would take to get a hole/jigsaw.

 

[PCUK]

What other tools have you already got? Dremel? Multi tool saw? router? All these would do it. I think many folk here can't understand why you aren't using this job as an excuse just to buy a jigsaw!:nonchalance:

 

[mrming]

What other tools have you already got? Dremel? Multi tool saw? router? All these would do it. I think many folk here can't understand why you aren't using this job as an excuse just to buy a jigsaw!:nonchalance:

That's exactly what I was thinking.

I have so many power tools that I would simply never own if I didn't have a boat. You buy them for a one off job, but they usually come in handy again and again.

I'm hoping not to have to use the random orbital sander in anger again for a while though. Maybe once my course of counselling is complete.