|Chris TickTock||04/09/2020 14:05:50|
|586 forum posts|
I have lost a few pounds cutting 50mm square aluminium with my 12 inch hacksaw. I tried cutting liquid but still hard.
Is there a better way to cit this would a bigger tooth saw be better? How does aluminium cut with an angle grinder, my memory tells me it snatches?
|larry phelan 1||04/09/2020 14:21:55|
|820 forum posts|
I would imagine that a course blade and WD40 would help [fine blades clog up with Ali ]
50x50 is not too big and the exercise will help to build up a thirst to justify a trip to the pub later on.
Plan "B" would be to buy a Chinese junk bandsaw, like mine, still going strong after 20 years, and let it do the cutting while you do something else [like drinking the afore mentioned beer ] Just looking at it working would give a thirst. How do I know ? Ask me !
Life is too short to waste your time in that manner, cop yourself on. I gave up that game long ago and now use the hacksaw only when I have to. That,s what bandsaws were made for.
|800 forum posts|
How many TPI on your hacksaw blade ? 12" blades are available in various tooth counts from 10 to 32 TPI.
For a 50mm section soft material bar you would want a coarse pitch blade (10 TPI) & I would be lubricating it with WD40 or similar.
I would not try a cut-off wheel on aluminium unless the wheel was specifically rated to such use - aluminium clogs abrasive wheels, which can have unpleasant consequences.
|202 forum posts|
Try some chalk on the blade and in the cut, it helps stop the aluminium clogging the teeth. At the end of the day, big teeth, wide kerf and a bit of sweat. Oh sorry, and beer!
|Mike Poole||04/09/2020 14:55:57|
2739 forum posts
A coarse blade, 18tpi is probably the most common coarse blade. A rage type chop saw will make short work of this task. I have used a wood chopsaw but it can be a bit grabby and it did chip some Carbide teeth So not recommended. Using cutting fluid on a hacksaw with aluminium is a bit of a win and lose, it cuts nicely but clogs up more.
|Peter G. Shaw||04/09/2020 15:19:10|
1165 forum posts
Yes, 18tpi blades and use paraffin to lubricate the cut and to help wash out the chips (it doesn't need much).
Peter G. Shaw
|Dave Halford||04/09/2020 15:50:15|
|921 forum posts|
In my youth I was guilty of using a B&D circular saw attachment on a two inch block of ally.
Drill in low gear and a slightly blunt HSS blade. The shrapnel was murderous, but the block was cut, the drill survived and the blade was not noticeably blunter.
|455 forum posts|
Now, as for technique with your new blade:
With the bar in your vice, start sawing 'uphill' (from bottom front to top mid) then saw 'downhill' (from top mid to rear bottom). This will give you an inverted V shaped slot. Cut off the apex then resume as before. The logic behind this is that your cuts are shorter than just cutting straight across the bar.
Thanks to Tubal Caine (Tom Walshaw) for this method.
Now I've got a power hacksaw, my muscles have become all flabby without the use of Armstrong's Patent.
|Adam Mara||04/09/2020 16:04:44|
|118 forum posts|
At work they cut a lot of aluminium section, from memory its a DeWalt chopsaw with a aluminium cutting blade, which are available.
|Stuart Bridger||04/09/2020 16:18:32|
|476 forum posts|
I feel your pain, I went through the same with a 3 x 1 1/2 section and purchased a bandsaw for the next time!
Edited By Stuart Bridger on 04/09/2020 16:24:23
|Chris TickTock||04/09/2020 16:33:35|
|586 forum posts|
Thanks guys I appreciate all posts and will note comments for the next time.
6322 forum posts
Don't ask how I know, blush, but a common beginner mistake is sawing too fast and with too much pressure.
Let the tool do the work! Gentle down pressure only with each cutting stroke taking about a second. Also try to use the full length of the blade otherwise all the wear occurs in the middle, and the blade goes blunt quickly on the section doing all the work. Have a good look at the teeth in the centre of the blade through a magnifying glass - they may be blunt or clogged. Dump blunt blades.
Blades wore quickly and sawing was exceptionally hard work when I started. They last longer and the job is easier now my technique has improved. I put it down to learning to work the teeth in the sweet spot between excessive wear due to forced cutting, and blunting caused by rubbing. Teeth should cut with as much of their edge as possible but no more. Forcing a blade deeper than the length of its teeth causes severe wear and multiplies the effort needed to remove metal.
In other words, try slowing down and don't force the blade into the metal.
I love my cheapo 6x4 band-saw! Sawing by hand is too tiring and tedious.
|479 forum posts|
I learnt from my Grandfather about sawing, he was not an engineer but a carpenter. He had a little rhyme to which you applied to the sawing "hold on tightly press on lightly" sawing to the rhythm of the rhyme. It works for wood as well as metal.
|Noel Murphy||04/09/2020 17:11:02|
|12 forum posts|
How can you tell if a cut off disk is rated for aluminium? Is there a special symbol? Searching for 'aluminium cut off disk' doesn't help because they all contain aluminium oxide.
18868 forum posts
Should have it written on the disc like these
|larry phelan 1||04/09/2020 18:07:48|
|820 forum posts|
Like me, S-O-D got a pain in his butt with the hacksaw !!
Long live the cheapy junk bandsaw !!!!!
|Bob Worsley||04/09/2020 18:15:16|
|55 forum posts|
If cutting with something toothed then must use a lubricant to stop it welding to the tooth tip, WD40 is fine.
Any stone angle grinder disc will happily cut aluminium, steel will not work. I know because I cut a CVRT aluminium tank in half to shift it to the scrappy.
The Evolution metal cutting saws are brilliant, the Clarke ones aren't.
|norman valentine||04/09/2020 20:13:56|
|249 forum posts|
i use 1mm cut off blades in my angle grinder, they work fine.
The cheapest I can find>
|roy entwistle||05/09/2020 10:32:49|
|1251 forum posts|
Norman For cutting aluminium ?
|norman valentine||05/09/2020 10:35:31|
|249 forum posts|
Roy, yes for aluminium.The blades are designated for cutting stainless steel and they do not clog up on aluminium.
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