Cutting metal

[steamcoal]

A general question.

If one is to cut and trim plate metal, thin brass or steel,say for tender construction or running boards and the like, what is the preferred equipment to undertake that task?

Might it be a cut-off disc and grinder, metal cutting bandsaw or manual shear or a combo shear, rolls and folder used.

Be interested in what people use in their workshops.

Hayden

[simplyloco]

Apr 1, 2022 10:09:11 GMT steamcoal said:

A general question.

If one is to cut and trim plate metal, thin brass or steel,say for tender construction or running boards and the like, what is the preferred equipment to undertake that task?

Might it be a cut-off disc and grinder, metal cutting bandsaw or manual shear or a combo shear, rolls and folder used.

Be interested in what people use in their workshops.

Hayden

Hi. 
I made a bench shear out of 3/8" gauge plate for the bigger bits. I normally use a combo shear, roll and folder, and a jeweller's saw for the tricky bits!

[stevep]

I find shears tend to distort the edges, so I keep a second hacksaw frame with the blade mounted sideways for cutting sheet, although it does limit the width you can cut to the depth of the frame.

[rrmrd66]

Hello Everybody

Whilst on the subject what are members preferred methods for tackling the edges left by laser/water jet/gas(?) cutting equipment.

The excellent frames that MEL provide have a very hard "wound" that looks unsightly. Is it a question of draw filing off dressing them with an abrasive belt sander?

Cheers

Malcolm

[Deleted]

Hi Malcolm..I use a belt sander and dremel drum sander for tighter spots before finishing with files ( or machine when doing rods) once the hard surface is gone.

[Roger]

I use the CNC Mill for all of those items. You can drill all of the holes and apertures at the same time. if it's really thin, you can make a sandwich and clamp on top of a thicker material. You can also use double sided tape to stick it down. I use a liquid Label Remover to soak the tape so it can be removed.

[92220]

For all shaped pieces of sheet metal, I use the mill and mill the outline. If the sheet is as thin as a piece of shim, I sandwich it between 2 pieces of 2 or 3mm plate and then mill the outside shape, and drill all the holes with clamps close to the holes to get a well shaped hole with almost no burrs. I've cut holes from 0.6mm right up to 7/8" dia in 0.2 nickel silver sheet, and in shim steel. I just hate hand working sheet material, so always try to find a way of machining on the mill. At least I can be sure edges are straight and dimensions are within 2 or 3 thou of what I want. It does allow me to make some very small, accurate, and fiddly scale fittings.

Bob.

[Gary L]

Apr 1, 2022 11:00:25 GMT rrmrd66 said:

Hello Everybody

Whilst on the subject what are members preferred methods for tackling the edges left by laser/water jet/gas(?) cutting equipment.

The excellent frames that MEL provide have a very hard "wound" that looks unsightly. Is it a question of draw filing off dressing them with an abrasive belt sander?

Cheers

Malcolm

If I understand what you mean correctly, the unsightliness of the ‘wound’ is mostly oxide discolouration that will disappear under the paint. In some ways it is easier to deal with than a machined edge, because there is no burr to get rid of.

It is true that the laser finish on (say) the edges of a frame is not perfectly smooth, but then this kind of cut is not perfectly smooth in full size either, where flame-cutting would have been the general rule. But to reduce the roughness, draw filing is as good as anything. I would personally avoid a belt sander, because the laser-cut edge is accurately square (except in thicknesses >¼” or so), and the belt sander can be a bit fierce and might make matters worse in this respect.

However bear in mind that laser-cut steel (and only steel) has a thin but very hard skin, which will soon blunt any file you use on it. That might be discouraging on long lengths! In general I content myself with breaking the sharp corner so that it will take paint better, but that could just be a reflection of the large scale I am working in.

HTH

Gary

[coniston]

I use a number of options depending on what I am cutting and how big it is, as mentioned a hacksaw with blade at 90 degrees, or combined shear/roll/brake press as Simplyloco mentioned. for long lengths I have had success using a DIY jig saw against a straight edge, use a fine metal cutting blade and take it easy, surprising how quickly it goes through.

Chris

[doubletop]

I hack out what I need from the sheet with a jigsaw and then use the mill to finish. If you have DROs on the mill, Other than the standard X and Y cuts you can acheive some pretty intricate shapes with the Smooth Arc and Line of Holes functions in plunge milling mode. As I have a small mill usually go for a 1/4" cutter 0.020" step which can easily cleaned up with a quick run over with a file and wet and dry. A larger cutter does leave a cleaner cut for the same step size, but a larger radius in the corners.






I have one of the small combo brake, press, rollers but it can't handle long cuts above, say, 1mm brass



Pete

[SteveW]

Maybe a bit off-the-wall but with very thin brass material I have had some success using a Stanley knife and straight edged. If not cutting completely through it is some times a score and break technique but this depends to some extent on the hardness of the sheet metal.

[92220]

I've been playing around with 0.008" steel shim. I have found I can cut intricate shapes with a pair of decent quality scissors...even where 2 pieces overlap by 10mm, where I've joined them using structural epoxy glue. The scissors don't seem to be getting blunt either! I have gone as far as using the same scissors to cut 2 pieces of 0.01" steel shim. Though the joint is harder to cut, it can be cut with the scissors.

As an 'Aside'...I don't know if others have found, and used, this structural epoxy. It is amazing stuff. Itn first came to my attention in a TV program about supercars and how some use this adhesive to fit tyhe bodies to the chassis, with no metal fixing like nuts and bolts. So far, the best one I have found, is Araldite 2021-1. It is one of the quickest, that I have found, to cure to a state where the assembly can be handled. I also use Loctite EA9466. The Loctite is cheaper and is slower curing, but a slightly stronger joint than the Araldite. Both adhesives come as a double syringe and have top use a "glue gun" which you can get with a 'first buy'. The glue gun will then be used for future syringes. There is no mixing involved because the nozzles are mixer nozzles. There is always a bit of wastage of glue with each use because the nozzle is always left in place and the tip dries hard. It can then be removed at a later date and be replaced with a new nozzle. The nozzles that suit the Loctite are much cheaper than the nozzles that fit the Araldite syringes. I keep a pack of each epoxy, and only use the Araldite when I need a quick handling of the assembly. As far as the strength of a joint goes, I have glued 2 lumps of aluminium together and the only way I could break the joint was to find a place where the adhesive hadn't quite filled the joint and I was able to just get the end of an old woodworking chisel into it and I had to hammer it really hard, with a lump hammer, to break the joint.

Bob.

[simplyloco]

Apr 7, 2022 8:06:02 GMT 92220 said:

I've been playing around with 0.008" steel shim. I have found I can cut intricate shapes with a pair of decent quality scissors...even where 2 pieces overlap by 10mm, where I've joined them using structural epoxy glue. The scissors don't seem to be getting blunt either! I have gone as far as using the same scissors to cut 2 pieces of 0.01" steel shim. Though the joint is harder to cut, it can be cut with the scissors.

SNIP

Bob.

Hi Bob
I've discovered recently 'JB Weld' which dries overnight to a steel colour and is immensely strong.
Don't look too closely at my recent creations...
John

[92220]

Hi John.

Thanks for that info. I will try it to see how it compares. I've just had a look on the 'net. It does look very interesting!!

Bob.

Edit:  It's also a whole lot cheaper than either of the epoxies I've used!!!

Bob.