Aluminium extrusions

I have tried the usual searches without finding what I am looking for.

Does anyone on the Forum know if a tapered section is included as a standard shape for extrusions or do you have to supply the die for it to be made from?

I rather suspect that is the case.

Specifically, I am looking for a 5 degree angle on one side of a strip of 6 mm thick aluminium 60 mm wide in a length of 3 metres. The angle isn't critical, it could be 8 degrees; it is more a search for what might be regarded as a standard supply shape. I am sworn to secrecy on the intended use.

Any leads you can provide would be very welcome

Thank you Brian

Have you tried CAPALEX in Cumbria.

I have bought from them in the past, but now they refer individuals to one of their stockists, none of which are local!

There is an online catalogue of 'standard sections'

Hello Keith,

Thank you for the information but they only offer standard regular sections in the profiles they show.

The search continues!

Brian

Brian,

Depending on how many you need, and the finish required, it might be worth considering using standard rectangular material and then machining the bevel, much as you might on wood using a spindle molder. There are off-the-shelf metal bevelling machines – the one in this link only goes to 14 degrees but I’m sure something similar could be found to do a shallower bevel.

https://www.baileighindustrial.co.uk/beveling-machine-cm-6-1

Hello Dave,

I really want to avoid the need to do any machining other than sawing sections off the profile as necessary.

It will only add unacceptable costs to the project, as well as time and holding problems that can be avoided completely by getting the profile right from the start.

Thank you though for the suggestion, it was valid but not what I was looking for I'm afraid!

Kind regards

Brian

Brian, how about a plasterer's Feather Edge in aluminium some are solid some are hollow section depends on size / length. Link is to Amazon but plenty of variations in style and suppliers Might be a bit pricey if you need lots!

John

Internal or external bevel? How far across? Eight degrees over 60mm is greater than the original thickness.

Take your length to someone who would machine it, is my advice, if you are not prepared to do it yourself.

Hello John,

Rather pricey as you say and the wedge angle needs to be full width across the section for the intended application . Otherwise a good suggestion but not right in this case I'm afraid. Thank you for pointing it out

Regards

Brian

Hi Brian

If you need more than a couple of tons it might be worth getting a die (and backing) made, otherwise machining a stock profile or cut sheet would probably be cheaper.

This would probably need to be a two or three port die to reduce the pressure and avoid breakage. I don't think an extruder would use a die you supplied, if only because it would most likely require 2 or 3 caustic + rework operations before producing a clean and accurate profile. If the face of the profile is to be visible, a pattern of fine grooves and ridges would hide any lines from die pickup.

I am a bit out of date now, with most of the extruders I used to deal with being long gone or swallowed by Hydro but once you get to 5-10 tons or so, the price per tonne, even including the die cost, should be comfortably less than from a stockholder.

Brian

Hello Brian,

Thank you for some useful information from someone with field experience.

The project is currently in it's very early stages and far from the stage of committing to that sort of investment. What is being looked for at this stage is to try and get it off the ground and become self supporting, facing as it does an uncertain sales reception for something a bit out of the ordinary.

So you will see that there are many uncertainties here for a new concept and any major expenditure is going to kill it at birth.

Hence the quest for an established profile that is available as required and can be used as required until the idea gets some maturity.

That avoids having to buy in large quantities with a far from certain hope of recovering even the outlay, let alone hope to make a modest profit to plough back into the enterprise

I am beginning to think that the concept is struggling to get born at this stage, but continue to remain hopeful !

Kind regards

Brian

Edits for spelling

Edited By Brian Wood on 07/03/2018 13:55:56

Would laser cutting be an option?

I wonder if a wood router would do the job in minutes ??
BobH

Hello Brian,

I take you mean slicing off the taper down the side of 6 mm flat strip. I really have no idea but I imagine it would be too expensive to consider as a means of making the stock for this project. By the same token water jet cutting would work equally well, but the jigging for both on a sensible length of strip might be rather tricky to set up and hold to spec.

From the experience I gained at my last place of work, the boss had experiments done on these forms of profile cutting in flat 10 mm boron steel plate and found they were more expensive than plain old oxy-acetylene torch cutting. Being a canny Yorkshireman he would know fine well what he was taking about! The finish was superb with smooth edges, but that didn't count at all in the financial considerations

Thank you though for the suggestion, this post is plumbing people's imagination if nothing else

Kind regards

Brian

Hello BobH

I really wanted to avoid all methods of machining the plain strip and just buy in profiled stock I can use directly with no more to do that bandsaw it to the lengths needed. That was why I was seriously considering the extrusion process, the shape is truly simple and length is only limited to the size of the billet that is extruded. Thus far it is not a stock shape, even as a taper of any narrow angle.

To rout this shape would need a hefty router to hog off a taper on 60 mm wide material in one pass and just holding the work down at the required angle to do so would present real problems. Milling with a full face or fly cutter is equally limited by the length that can be held on the table and a jig would be essential in both cases to hold it under control , the narrow edge in only 1 mm or so from breakthrough.

Likewise I think a spindle moulder would struggle to do this, they don't as a rule provide a means of angling the cutter to make a full face taper, the fence yes, and without looking into getting custom shaped carbide cutters made, which would not be cheap, I can't see my bespoke cabinet maker acquaintance in town being very keen to stuff aluminium through his expensive spindle moulder that his living in part depends on!

So I am sorry, I've already dismissed those kinds of solutions as being far too expensive and only capable at best of producing short lengths. If this project gets off the ground as I hope, the supply situation needs to be as rapid and easy as possible.

Kind regards

Brian

Brian,​ would it be at all possible, even it it were to be purely for the prototyping and maybe alpha or beta test stage of product development, to utilise folded sheet section? As you state that you will saw to length, short sections could be folded in one piece with an internal flange bonded to the 'flat' side,though 3 metre long pieces would most likely require to be made of 2 pieces bonded together, one a vee and the other a channel. Redux or some such process might suit? This would not be as cheap as bulk produced extrusion, but much cheaper than converting 45% stock to swarf!

Trevor

My inclination would be to see if teh section can be designed out, at least for the prototype stage.

It's hard to make definitive suggestions as we don't even know if its cosmetic or a critical working part, let alone the likely duty etc.

Is it absolutely essential to have taper section rather than a rectangular section at an angle, or just a thick plate at an angle, perhaps pop riveted to a supporting section?

Neil

Trevor and Neil

Thank you both and taking your points in turn. Folded section is not on Trevor I'm afraid as there will be pressure applied to the tapered face when these components are used in anger and the rigidity will not be there to meet it, and to answer Neil the taper shape on one side of the strip is essential to the function.

I'm sorry to be so cagee about the planned use but I really don't want to reveal the concept as it is novel and I would like to exploit the idea if that is possible, so please accept that a solid material is essential, the tapered face to the rear ditto and the front face is to be held upright by pressure applied from the back.

I may in the end have to accept defeat on the plan simply through lack of suitably shaped material as a feed stock. Making the shape I am looking for is too fiddly and expensive to justify the expense for a final product that is intended to be cheap and cheerful and have the appeal to fly off the shelves. If that is the case then I will write it off to experience and present it in an article for MEW as an idea which any individual can easily make for him or herself as a piece of workshop tooling

Until then though I am hopeful of a breakthrough of some sort that I have missed or failed to see but it is beginning to look to be a rather unlikely result

Thanking you all again for your thoughts and suggestions, even if they are not what I was hoping to read.

Kind regards Brian

Found this company name who do seem prepared for small runs or one-offs...

Holden Aluminium

**LINK**

Or these people, Aluminium Shapes

https://alishapes.co.uk/approach/extrusion/

Edited By Brian Sweeting on 07/03/2018 23:55:23

Brian

Does it have to be aluminium? (in which case, you would be looking at an aluminium producer, not a stockholder).

What about a hard plastic, nylon or similar?

These people may be able to produce what you want **LINK**

Does it have to be ally? You can get steel tapered washers made for putting under nuts when bolting through the tapered sections of large steel I beams or channel. They are a square shape with hole in the middle and tapered in cross section to match the I beam shape. Or could you use sections cut out of a large I beam or channel, on the tapered flange sections? (Groping in the dark here without knowing the application!).

Edited By Hopper on 08/03/2018 01:51:59