Cutting Thick Aluminium "Box Section"

[Richard10002]

I recently bought and fitted a Lagun pivoting table mount which, amongst other things, can be raised and lowered.

 

It works great, but I want to be able to lower it by a further 2 inches, which requires cutting 2 inches off the bottom of the leg.

 

The leg is effectively a box section of quite thick aluminium which I was hoping could be cut with my Dremel. Given time, I could probably do it, but it wasnt going to look neat, and would take forever. I've also tried a small hacksaw, which would take longer than forever  

 

I'm wondering what other ways people would use to do the job.

 

This is the leg that needs cutting:

 

https://shop.chastheboat.co.uk/products/spare-leg-for-lagun-frame-32109

 

 

[Higgs]

5 minutes ago, Richard10002 said:

I recently bought and fitted a Lagun pivoting table mount which, amongst other things, can be raised and lowered.

 

It works great, but I want to be able to lower it by a further 2 inches, which requires cutting 2 inches off the bottom of the leg.

 

The leg is effectively a box section of quite thick aluminium which I was hoping could be cut with my Dremel. Given time, I could probably do it, but it wasnt going to look neat, and would take forever. I've also tried a small hacksaw, which would take longer than forever  

 

I'm wondering what other ways people would use to do the job.

 

This is the leg that needs cutting:

 

https://shop.chastheboat.co.uk/products/spare-leg-for-lagun-frame-32109

 

 

 

I don't think a Dremel-like tool is a good idea. The disks will not handle it and will disintegrate quickly. Something like a cutting disc on a grinder would be better. Failing that, a slower job with the hacksaw. Some chop saws are ok with aluminium. 

 

 

Edited October 24, 2022 by Higgs

[Tracy D'arth]

Get a proper hacksaw frame and some 12" or 14"blades meant for aluminium. Forget the junior toy hacksaw.

[Jen-in-Wellies]

6 minutes ago, Tracy D'arth said:

Get a proper hacksaw frame and some 12" or 14"blades meant for aluminium. Forget the junior toy hacksaw.

This and a mitre box to keep the cut perpendicular. Will go through it in no time at all.

[bizzard]

With a set square or whatever draw a line around it that you can follow with hacksaw or cutting disc in an angle grinder, if you have no mitre box.

[Ronaldo47]

For cutting metal, a 1mm disc on an angle grinder works for me.  

[dmr]

Ali is dead soft and a full sized (not junior) hacksaw with a good blade will cut it easily. If you are not an expert then it can be tricky to do a neat square cut so maybe cut just a fraction over-size and tidy up with a file.

A 1mm cutting disc in a grinder is probably overkill, but these are a great tool and with confidence can do very tidy cuts quickly. Its worth learning how to use these things but maybe practice on an offcut first.

[beerbeerbeerbeerbeer]

Full sized hacksaw. 
👍

I think I’d cut across each flat face one at a time. 
Turning the square of the leg each time in the vice. 
 

 

[pete23]

I’ve a electra becham chop saw saw I use for fine woodwork it has a 80 tooth non ferrus blade in it and loves cutting aluminium..

[blackrose]

17 hours ago, Ronaldo47 said:

For cutting metal, a 1mm disc on an angle grinder works for me.  

 

Me too. With aluminium the disc will drag as it cuts the soft metal and will wear out quickly but it works fine. Let the disc do the work. 

 

If you already have an angle grinder then just buy a couple of slitting discs. If not then use a hacksaw and a file to clean up the burrs.

Edited October 25, 2022 by blackrose

[Slim]

19 hours ago, bizzard said:

With a set square or whatever draw a line around it that you can follow with hacksaw or cutting disc in an angle grinder, if you have no mitre box.

An easier way is to wrap a sheet of A4 paper around the tube tightly a couple of times making sure that the edge is perfectly aligned then stick with a bit of tape. Cut to the 'leading' edge.

[Martin Nicholas]

A metal cutting blade in any sort of circular saw is the thing. The blade in my Parkside plunge saw is for: "Soft wood, soft metal such as aluminium, copper, plastics." Recently used it to cut 6mm Al plate.

 

An angle grinder is the WD40 of the machine tool world.

[beerbeerbeerbeerbeer]

You could of course have it laser cut. 🤡

[Jon57]

50 minutes ago, Goliath said:

You could of course have it laser cut. 🤡

Or even drill a large hole in the floor 🤣🤣

[dmr]

Gas Axe ?????

[Richard10002]

Thanks for all the advice.

 

In the end I bought a proper sized hacksaw and a £35 angle grinder. Hacksaw worked a treat, and I now have a grinder for that job that I dont even know exists yet  

[dmr]

12 minutes ago, Richard10002 said:

Thanks for all the advice.

 

In the end I bought a proper sized hacksaw and a £35 angle grinder. Hacksaw worked a treat, and I now have a grinder for that job that I dont even know exists yet  

Get a couple of grinding discs, a couple of 1mm cutting discs and a wire cup brush and find out what the angle grinder can do (and take care, ear and eye protection essential). I have used angle grinders all my adult life but a couple of years ago I treated myself to the Makita battery version and its just great on the boat, ready and waiting for all sorts of quick little jobs without having the faff of extension leads.

[Jon57]

4 hours ago, dmr said:

Get a couple of grinding discs, a couple of 1mm cutting discs and a wire cup brush and find out what the angle grinder can do (and take care, ear and eye protection essential). I have used angle grinders all my adult life but a couple of years ago I treated myself to the Makita battery version and its just great on the boat, ready and waiting for all sorts of quick little jobs without having the faff of extension leads.

Yep can even cut off chained up locks if you feel the need. Used mine on a swing bridge which the locals put a bike lock on to stop it be opened. Not for long. 😁😁

[Alan de Enfield]

21 minutes ago, Jon57 said:

Yep can even cut off chained up locks if you feel the need. Used mine on a swing bridge which the locals put a bike lock on to stop it be opened. Not for long. 😁😁

 

Everyone seems to walk about with a small rucksack these days - add a battery angle grinder and the scrotes can easily 'go equipped'

No padlock, no fuel filler or battery straps, or cables, immune.

 

Simply "wizz-cut-and go".

[bizzard]

7 hours ago, dmr said:

Get a couple of grinding discs, a couple of 1mm cutting discs and a wire cup brush and find out what the angle grinder can do (and take care, ear and eye protection essential). I have used angle grinders all my adult life but a couple of years ago I treated myself to the Makita battery version and its just great on the boat, ready and waiting for all sorts of quick little jobs without having the faff of extension leads.

And flap discs for the angle grinder brilliant for cutting through paintwork to metal without scoreing it.  I take it Richard bought the usual 4.1/2'' angle grinder and not a 4'' which are about.

[Richard10002]

3 hours ago, bizzard said:

And flap discs for the angle grinder brilliant for cutting through paintwork to metal without scoreing it.  I take it Richard bought the usual 4.1/2'' angle grinder and not a 4'' which are about.

 

It's a Black and Decker from B & Q, which came with 5 x 3.5mm discs, and I bought a couple of 1mm metal cutting discs as well. The discs are 115mm, which seems to be about 4.1/2" .

 

Seems quite chunky and solid.

[dmr]

I've been using a workshop at a local farm, they find changing discs a faff so have a rack of angle grinders, one for each disc,, a grinder, a 1mm cutter, a flap wheel and a cup brush, that really is luxury.

[cuthound]

On 26/10/2022 at 16:56, Alan de Enfield said:

 

Everyone seems to walk about with a small rucksack these days - add a battery angle grinder and the scrotes can easily 'go equipped'

No padlock, no fuel filler or battery straps, or cables, immune.

 

Simply "wizz-cut-and go".

 

The scrotes local to me use battery angle grinders to remove and weigh in the farmers galvanised gates. ☹️

[Samp94]

Evolution rage mitre chop saw with a tct with cut that in seconds with a perfectly clean cut