|Martin Kyte||22/06/2020 15:51:14|
2462 forum posts
Just a curious question really. It's me that is curious not the question. Do people find that it ends up as false economy working from scrapyard chuck outs, bin ends and other assorted size materials or is it really worth it. as opposed to close to size parent material of known composition. I frequently read of members here spending ages wrestling with large lumps of steel etc on smallish machines just carving out a blank to actually set to and machine a componant. Fair play to them and it may be heroic and all but are you spending too much time just cutting stuff up instead of actually making parts. With the internet and delivery times making correct sized material available almost next day is it really worth the hastle of reducing that peice of 2 inch by 1 inch bar down to 2 1/4" x 7/8" before you even start on the job let alone the time spent and the wear on sawblades/ milling cutters etc. I used to do all this but managed (largely) to kick the habit and I find I not only get more done but there is more of the enjoyable bits compared to the hard work.
I'm sure a lot of it is just habit. I wonder what others think.
Edited By Martin Kyte on 22/06/2020 15:51:34
5926 forum posts
Of course you get he experience which is 'priceless'
|Clive Foster||22/06/2020 16:07:54|
|2739 forum posts|
I too need to kick the habit too, except for unfeasibly expensive large lumps for large jobs.
I've got the equivalent of 3 or 4 filing cabinet drawers full of potentially useful bits. Which, truth to tell, only realistically come in handy a few times a year.
Objectively I do the worst of both worlds. Buy for anything of respectably predictable size and keep all the crap I shall, most likely, never use.
Old farts like me still remember when getting materials in small quantities at affordable, or even un-affordable prices was all but impossible. Access to works scrap bins being a prized privilege.
I suppose the real answer is a modest collection of known offcuts in useful sizes. Once full the box is periodically refreshed when a "more useful than whats already in the box" size arrives with the least useful being binned. Instead of starting another box. So far I've tried twice resulting in dismal failures. I guess I'm a born pack-rat.
20908 forum posts
I just wish I was able to turn 2 x 1 bar into 2 1/4" x 7/8" like you
I don't think it is worth it by the time you have faffed about trying to get a good finish, made more swarf than you really need to and worn out cutting tools there is not much of a saving.
|Andrew Tinsley||22/06/2020 16:31:09|
|1447 forum posts|
I quite often use scrap material, but only if it is about correct dimension and it machines OK. I can't really see a problem if you keep to those rules.
|Mark P.||22/06/2020 17:03:10|
619 forum posts
Being time rich and monetary poor, I tend to use scrap bin materials.
|1382 forum posts|
I do as Andrew. Most of the scrap I get for free from a milling, turing and welding shop and they tend to use S355 steel which machines OK. If I find the steel unsuitable I just return it to the skip. Some of the Cast Iron I use come from old disc brakes, it is fine grained and machines well. Certainely not as expensive as ordering online.
|not done it yet||22/06/2020 17:26:26|
|6092 forum posts|
If my brother gets excess structural steel left over from a job, I am quite happy to use that steel.
I know of someone, recently, that paid a fiver for a metre length of 50mm x 3mm square steel tube. Not stolen!
I cut up an exercise bike recently, for the steel for a cutting and welding job. Should be OK as it was all welded together originally. More than adequate to make the support for a cutting table conversion of the band saw, for vertical operation. I expect I shall retain some round from it, too.
Anyone want the cast wheel? It is about 300mm diameter x 25mm at the rim. Still has a free-wheeling sprocket affixed to it.
I’ve often annealed steel shafts from scrap agricultural machinery - as long as the material machines OK. Stick a piece in the kiln, heated on E7 power and left to cool slowly.
You don’t think that Myford Boy (on you tube) buys in freshly produced aluminium for his casting projects, do you?
I have a stock of bought-in materials as well, of course.
I have machined down socket drive extension bars before now. And lots of other bits, too.
|Rik Shaw||22/06/2020 17:32:34|
1432 forum posts
My steel / iron stock of known flavours would probably weigh in at a ton or more but my first port of call for a new job is invariably the four large hoppers of scrap under one of the benches. I get a kick out of turning a rusty lump of tat into a useful tool or model part. For me it is all part of the pleasure !
Rik (eying up a sash weight for the pair of pistons I need) .
|pgk pgk||22/06/2020 17:50:18|
|2193 forum posts|
I get bits of steel plate as scrap from a local steel framed agri building place via local scrappy - pick out what i want when he collects a trailer load and it's quite satisfying to turn rusty black stuff into parts. If I was commercial or in a rush it'd be a different matter. Other sized stuff gets bought from ebay, m machine etc depending on price.
1141 forum posts
I needed some material for a small solid flywheel, it was either going to be brass or stainless; my brother in law worked at a local engineering company before he retired and they used the full spectrum of stainless alloys from 316 to hastelloy and inconel. He said he would get me a bar end of 316 from one of the autos, he duly arrived with a 3 inch diameter blank about 3 inches in length, just what I needed. When I came to machine it I couldn’t touch it with a HSS tool I had to use carbide tooling and wind the speed up to remove any material, the finish I got was good. I think the reason that it was so hard to machine was because it was a bar end from an auto which obviously cuts at high speed generating a lot of heat subsequently work hardening the material adjacent to the cut area. The provenance of the bar end was not clear, it had no material ident, it could have been some other stainless alloy which might have been a difficult proposition for machining anyway. I think the moral is try to obtain materials with a known provenance, it can make life easier.
20908 forum posts
He certainly buys in the ZL12 Ingots
|Martin Kyte||22/06/2020 18:49:44|
2462 forum posts
Some interesting comments. I'm particularly bad at storing excess wood which is a dreadfull eater of space. It's all about balance really. I think we all suffer from old habits which suited our purpose once but as time change tend to hang around. As far as time rich, well yes I guess I am time rich as I'm semi-retired but I'm also cash rich too compared to years ago. However when I think ahead maybe I'm not so time rich as I might think. There certainly is 20 years less time left than 20 years ago. My mate died suddenly recently and he thought he was time rich too.
|not done it yet||22/06/2020 18:54:38|
|6092 forum posts|
Sorry, not picky proof without the “all’ which I should have inserted between the ‘for’ and ‘his’.
|Mike Poole||22/06/2020 19:11:23|
3014 forum posts
Nothing wrong with scrap and off cuts, but if you know what they are it helps, some are best left in the bin.
|Oily Rag||22/06/2020 19:56:17|
448 forum posts
I have had some genuinely brilliant 'gifts' of scrap from friends and neighbours.
One instance I had a knock on my door around tea time and opened it to find a near neighbour who is a builder with 3 10 ft (3mt) lengths of 25mm steel bar on his truck - "these just fell of a wagon on the by pass and I picked them up as they may be dangerous, thought you might be able to make use of them"
Another time, I have a friend who worked for Rolls Royce and I needed some 614 Titanium so I asked him if he could get me some 'noggin ends' - after a time he came round and said it was too difficult to get but he gave me the address of the scrap yard that handled all RR scrap and suggested I went there asked to see a named guy and mention that I'd been given his name by a certain person at RR. I went to the yard and they threw open the place for me to hoover up whatever I wanted! I asked how much and they surprisingly said 'no cost' so I made a tea kitty donation in thanks - that's always appreciated.
Since then I have had the run of their scrap! PB, Incalloy, Alum 2068 bar,EN 19, 24,32,33,40 - even some Copper Berylium off cuts. the later make excellent valve seats and valve guides.The great part about the scrapyard is they 'spark test' all the incoming scrap to sort it into grades for onward processing.
4572 forum posts
You learn a lot about different materials, but it can waste a lot of time concerning the learning curve
The time lost has been largely made up with new skills using an angle grinder and welder which allow me to fabricate some pretty ridiculous projects
It's about what floats your boat really
Some guys just cut out the middle bit and buy a fully built model steam loco while other guys spend 6 years of their lives putting one together
|Martin Kyte||22/06/2020 20:37:07|
2462 forum posts
Totally agree with that. I have allways maintained that the primary product of the workshop is enjoyment. Some get that from making something out of nothing, others like building up the workshop and still others really just want to get the model done. All pockets all ages. I guess my point was, just now and again it's good to re-evaluate practices and habits so we don't get stuck in a groove. I'm sure I 'made do' long after I didn't have too.
|Mark Rand||22/06/2020 21:27:28|
|1028 forum posts|
Picking stuff out of the skips at work can cause problems.
That 1 metre length of 3" diameter CZ121 brass* very nearly crippled me.
*Marked on the bar, complete with purchase order number...
|old mart||22/06/2020 21:36:32|
|3197 forum posts|
I made some super engine plates for a motorcycle back in the sixties with some very nice 1/4" aluminium plate from the scrapyard near where I worked. I have a hoard of metal under the benches at the museum, when the metal budget is zero, you learn to keep anything just in case.
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