Hot rolled angle problems

[Mick BaileyParticipant @mickbailey28509]

I started a Duclos Odds ‘n Ends engine but quickly ran into problems with the steel angle. I went to collect a length of 75x75x10 and didn’t look to closely but when I got it back theres an unequal heavy radius on the corner. I cut the pieces anyhow, but when I checked, the cylinder block screws break out of the edge of the radius. I suppose a heavy fillet of JB weld would disguise this, but it isn’t an entirely satisfactory solution.

Also, the angle isn’t flat across the face – its quite convex which I wasn’t expecting.

Today’s mission is to locate some angle with a square corner. The problem is that when calling the stockholders you get through to the office and they don’t know what the stock looks like – it’s a measurement and a price. I saw Andrew Whale’ s build and he has some decent material – is there something specific I need to be asking for?

 

 

[JasonBModerator @jasonb]

Not sure why the cylinder block screws should be breaking out they should be well away from the internal fillet. The ones that hold the side plates to the base do break through the fillet on the Duclos drawings but I would be tempted to drill those blind.

How concave are the sides, The original was 3/8″ material so you have 0.5mm to skim off to flatten them down. Personally I would leave it with the mill finish as the texture will make it look more like a casting. Once the basic 3 parts are joined together you can treat it a sa casting anyway and there is nothing critical that mounts to the sides so just set out from the ctr line.

You won’t find black bar without an internal fillet and bright angle will be hard to locate if it is even made.

I have seen others  build it with just flat sides screwed to the base or you could make the “U” from 3 pieces

[HopperParticipant @hopper]

Be aware that the two sides of the angle are unlikely to be dead square to each other, either. That might need to be taken into account when machining the top surfaces of those two legs. It might need assembling first and then machining.

[JasonBModerator @jasonb]

What plans are you working to? Just had a look and the book and he shows how the base screws breaking into the fillet are dealt with so it is not a problem if they do as it does not show on the finished engine.

And to answer Hoppers point the top and bottom faces both get machined by clamping back to back and milling as a pair. The rest of the feature sare machined once assembled into the basic frame.

[Mick BaileyParticipant @mickbailey28509]

The radius is on the outside corner, hence the screws breaking out. The vertical face measures 9.5mm and will be below 3/8″ when skimmed. The angle measures 10.1mm on one leg and 9.5mm the other. Maybe a quality issue?

Ideally I’d want to start with 10mm on both legs with a square or lightly radiussed outside corner. I see that some places list square edge or radiussed angle, but they’re out of the area. I’ll go up to the workshop and photograph what I have for furthe opinions.

[JasonBModerator @jasonb]

In that case use the angle with the 9.5mm along the bottom and the 10mm vertical. The bottom face gets skimmed thinner anyway and you will loose some of that external radius.

At 8-32 or M4 you could probably move the holes in 1mm

Even if there is an external radius the whole thing gets hidden so nothing to worry about.

[Mick BaileyParticipant @mickbailey28509]

This is how it looks;

 

 

[noel shelleyParticipant @noelshelley55608]

Hot rolled material of any shape is unlikely to be dimensionaly accurate or sometimes even true. Cold rolled may be better but then when you machine it things may change. Good Luck. Noel.

[HopperParticipant @hopper]

Looks like poor quality rolling. Most good quality angle is “sharper” than that. You might try a different supplier, but really you need to look at the material before purchase in today’s world. Bit of JB weld if the area is at all visible might be easier.

[noel shelley]

On noel shelley Said:

Hot rolled material of any shape is unlikely to be dimensionaly accurate…

That is misleading.

Hot rolled material is made to a specification. Part of that specification is dimensional tolerances.

For the item in question, the specification is BS EN 10056-1 and BS EN 10056-2. If the dimensions of the supplied item fall without those tolerances, it should be rejected.

See:

https://roymech.org/Useful_Tables/Sections/Angles_dim_prop.html

https://www.ajnsteelstock.co.uk/wp-content/uploads/2014/08/Rolling-Tolerances-2.pdf

[JasonBModerator @jasonb]

It’s a bit of a poor one, maybe end of the roll?

But at the end of the day it won’t show once it is all filleted in with Bondo (body filler)

[DC31k]

On DC31k Said:

On noel shelley Said:

Hot rolled material of any shape is unlikely to be dimensionaly accurate…

That is misleading.

Hot rolled material is made to a specification. Part of that specification is dimensional tolerances.

For the item in question, the specification is BS EN 10056-1 and BS EN 10056-2. If the dimensions of the supplied item fall without those tolerances, it should be rejected.

See:

https://roymech.org/Useful_Tables/Sections/Angles_dim_prop.html

https://www.ajnsteelstock.co.uk/wp-content/uploads/2014/08/Rolling-Tolerances-2.pdf

I think Noel sums it up correctly.

OP says he wants to start with 10mm material. But as your link shows he could get anything between 9.25mm and 10.75mm thickness so expecting 10mm nominal to be an accurate 10mm thick is not realistic.

[HopperParticipant @hopper]

I doubt the steel mills in China and India take much notice of BS anything. There is some pretty poor steel on the market in recent years. Yes it should be rejected, but who checks it? Nobody. Once again it is left to the consumer. Who only finds out when he gets it on the job and has started cutting it up, or starts hitting “diamonds” that even carbide tooling will not cut. (Rumour has it that Chinese recycled steel contains discarded carbide inserts that somehow make it through the smelting process. Seems unlikely, but some of those hard spots in their bright bar seem that hard, or harder. They will tear the tips off carbide tooling and snap HSS clean in half.)

[Mick BaileyParticipant @mickbailey28509]

It looks like I’ll need to work with what I have, or fabricate my own angle by welding. I rang around and nobody has anything close to 75mm – I’d have to order a 6m length. I never used to have a problem with steel quality or dimensions but about 20 years ago noticed a big shift towards lower standards with hot rolled sections as well as box section.

[JasonBModerator @jasonb]

having welded two bit sof angle into C channel a couple of times you do have to watch for it closing up. I’d be inclined to use 10mm flat material and use 3 pieces to make the U shape. Sides full height and middle cut to fit between. Some counterbored holes in from the side will hold it together and can be filled with JBW or body filler at the end when the other cosmetic work is done.

This sort of thing wich is the sole plate of an engine

 

[Mick BaileyParticipant @mickbailey28509]

I’ve tried running three heavy beads of weld along the radius then ground and filed back to give a sharp corner, but just on one piece. It’s too much work and I don’t fancy doing another. It would have been quicker to have welded up the angle from flat.

I cut another piece so that I still have a matching pair with the radius. At the moment I’m inclined to go with what I have then fill afterwards, as I already have the material. If I was starting afresh I would go down the route of a bolted assembly and use BDMS flat as you suggest.

 

 

[bernard towersParticipant @bernardtowers37738]

Ive just squared up a piece of hot rolled angle 75 x 90 on the shaper and it only needed 0.4mm shaved off each face to leave a razor sharp corner so if I were you it would go back.

[Mick BaileyParticipant @mickbailey28509]

I’ve already cut it up and can’t take it back- I should have checked when I bought it. I checked my other various offcuts and none has this radius. I can’t think why it would be like this, a rounded corner is understandable but not something asymmetric. If I had the choice a better piece would be preferable but there are no other stockholders that has anything even close. I thought 75×75 would be easy, even 100×100 in 10 mm, but nothing. Either that, or they have no interest in a hobbyist after a short length.

[David George 1Participant @davidgeorge1]

Not long before I retired i was involved in making a mould tool for Jaguar. One half weighed about 500Kg and we had spent two weeks CNC machining when we found a hard spot which would not cut as when tested with a hardness tester it was about 60 RC hardness. The customer would not accept the piece of material and it had to be replaced and the metal supplier would only replace the steel, P20 sulpher free and no compensation for time and tooling loss. It was found the material was from China and had a delay in replacing from alternate source.

David

[JasonBModerator @jasonb]

If you want to pay the few quid extra for postage then M-machine list 75x75x10 and if you e-mail them that image and say you want a fully formed corner I’m sure they will find you a good bit, they cut to length

[Mick BaileyParticipant @mickbailey28509]

There are a few things I need and it looks like ordering and paying postage for a job lot is going be the best way. It’s a nagging feeling of regret when making a decent job of something where the material is unsatisfactory.

 

[David George 1]

On David George 1 Said:

Not long before I retired i was involved in making a mould tool for Jaguar. One half weighed about 500Kg and we had spent two weeks CNC machining when we found a hard spot which would not cut as when tested with a hardness tester it was about 60 RC hardness. The customer would not accept the piece of material and it had to be replaced and the metal supplier would only replace the steel, P20 sulpher free and no compensation for time and tooling loss. It was found the material was from China and had a delay in replacing from alternate source.

David

I had the same problem in miniature recently on a piece of 50mm square BMS bar. Towards the end of hours of machining time, hit a “diamond” that just could not be cut. Ruined several carbide boring inserts and then snapped off a T section HSS parting blade. Mates still working in the trade tell me it’s not uncommon with Chinese steel these days. Frustrating to say the least.

[noel shelleyParticipant @noelshelley55608]

Where are you ? I have assorted off cuts of alsorts and may be able to help. Another thought is to use a lump of C section and cut out the middle. How long do you need ? Noel.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi, well I’ve cut, drilled, bolted, welded, etc.  very many tons of hot rolled angle iron, both equal and unequal, and of many different sizes. Very often, none of it has been exactly square, and not always the exact size that it should be, and occasionally some of it, both legs have been noticeably tapered from one end to the other, this over time includes that of which, much was made in the UK. As far as I’m aware, hot rolled sections have always been considered as structural, and not directly associated with precision work, but can be used if you are prepared to do a certain amount of machining on it, but you need to get a larger size than the finish you want. I have fabricated things where they have had 20% or so of the sections machined away, to be sure they finish to spec size.

Regards Nick.

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