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

[David2452]

I used to to do everything to perfection. Then I realised how much of my life I was wasting. Now I limit it to the bits that matter and the bits you can see.

< anal hat on > Not sure that would apply to this situation, a good hole saw would take about 30 seconds and to a proper job, same goes for using the right tool for any job, i sometimes cut holes for free in my own marina base (for existing customers) as I can't bear bodges of any sort.

 

[Lakesailor]

There you are Dan. A free hole cutting service......... Just sail around there.


I agree about doing it right. I am refurbishing a trailer at the moment. I cut a pad out of a kitchen cutting board to bolt between the axle beam and the trailer floor (gap 5mm), in the centre of the floor, just to stop that annoying clattering you hear from unloaded trailers as the floor flexes and taps the chassis.
But now and again I see the big picture and accept that "as new" is not always needed.

 

[Birdseye]

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?

hole cutter off ebay. I have one of a similar size - I'll check if its 140 and if it is you can borrow it.

 

[Greenheart]

That's more than kind, Birdseye, but given my restricted turning-power with the hand-drill, I believe I'll do as the Drascombe-owner did on the site in post 32...

...it's slow and laborious, but he managed to make it look very tidy, with very basic tools.

I'm very grateful for the offer, though! :encouragement:

 

[Mudisox]

I used to to do everything to perfection. Then I realised how much of my life I was wasting. Now I limit it to the bits that matter and the bits you can see.

Bit like my scheme for washing when on the boat!

 

[realslimshady]

I used to to do everything to perfection. Then I realised how much of my life I was wasting. Now I limit it to the bits that matter and the bits you can see.

Amen to that

 

[zzyyxx]

That's more than kind, Birdseye, but given my restricted turning-power with the hand-drill, I believe I'll do as the Drascombe-owner did on the site in post 32...

...it's slow and laborious, but he managed to make it look very tidy, with very basic tools.

I'm very grateful for the offer, though! :encouragement:

I still reckon a gaffer-tape (or the stanley knife someone suggested) handle on a hacksaw blade would make a neater job.

 

[Lakesailor]

Train some wasps to form circles and they will eat the wood. They do on our fence.

 

[Mudisox]

Train some wasps to form circles and they will eat the wood. They do on our fence.

Not my first thought on helping the washing problem.

 

[itchenseadog]

I thought the challenge was to come up with a way to cut a hole without using any of the tools that are normally used for cutting holes?

When I started out as an apprentice boatbuilder in the days before hand power tools, we had a pad saw handle with various width blades to fit. We used to cut 9" porthole appertures in 1 1/4" mahogany topsides by hand drilling 2 or 3 3/8" holes and joining them up before using the appropriate padsaw blade to cut the apperture. It wasn't too bad until you hit, and had to cut through, another 1 1/4" of rib. We thought we were doing well if we cut and fitted three portholes in a 9 hr day. I remember when we got our first 240v jigsaw. It was a heavy old thing and I think it was made in Switzerland, but what a difference that one jigsaw made to our output. The lads were practically fighting one another to use it !

 

[Greenheart]

When I started out as an apprentice boatbuilder...We used to cut 9" porthole appertures in 1 1/4" mahogany topsides by hand drilling 2 or 3 3/8" holes and joining them up before using the appropriate padsaw blade to cut the aperture.

I'll think myself lucky, having only 1/5" marine ply to cut through!

 

[zzyyxx]

When I started out as an apprentice boatbuilder in the days before hand power tools, we had a pad saw handle with various width blades to fit. We used to cut 9" porthole appertures in 1 1/4" mahogany topsides by hand drilling 2 or 3 3/8" holes and joining them up before using the appropriate padsaw blade to cut the apperture. It wasn't too bad until you hit, and had to cut through, another 1 1/4" of rib. We thought we were doing well if we cut and fitted three portholes in a 9 hr day. I remember when we got our first 240v jigsaw. It was a heavy old thing and I think it was made in Switzerland, but what a difference that one jigsaw made to our output. The lads were practically fighting one another to use it !

Padsaw! I was trying to remember what you called the bloody things!

 

[Lakesailor]

I knew I had a picture of stitch drilling somewhere.

Bit thicker than your stuff