GNJC Posted February 22, 2012 Author Share Posted February 22, 2012 Thanks for that Owen. There is no doubt that cast iron can be vulnerable in the situation you give; fortunately, the block in normal use won’t be under tension and would need a colossal blow to break it even then. I, too, have had cast iron break on me; but it has always been fairly thin e.g. pipe or motor casing. The thinnest place on the block that may take a stray hammer strike is pushing 2” thick; also, during working there will be soft metal between the hammer and the block; I'll also be surprised if anyone is daft enough to use a large hammer for the sort of work that the block has been designed for. I have really whacked what I think are the most vulnerable areas, using a 7lb hammer and have had no effect other than to produce dents. The block I have will go back for melting when I finish playing around with it, but before I take it back – Friday week – I shall get my wife to film me hitting it with my short-handled 14lb hammer and my long-handled 8lb hammer; a sort of destructive test. It may go first whack, or last forever. I’ll pass this on to any interested party. Colleen, I think the 4” thickness of a block will make a difference to its resilience, but I don’t know, so I’ll also try dropping it in the test above… before or after whacking? I’m often at friends’ places around Tring (near Ivinghoe Beacon and Aldbury), so I’ll happily drop a block off as and when. Is your chum a professional smith by any chance…? I intend to use the block on an adapted ‘table’ fitted on my current swage block stand. I’ll post a pic’ of my current stand tomorrow and one of the ‘table’ once I have made it. It will allow me to work at about navel height. Quote Link to comment Share on other sites More sharing options...
tzonoqua Posted February 22, 2012 Share Posted February 22, 2012 Giles, the pillar drill table was only about 30-50mm in places, with "struts" of thicker material, (if you know what I mean), and obviously not meant to be dropped from over a metre in height... I am sure the block will be fine!!! (Anyway, I don't have a power hammer to put it under, and I'm not one for picking up a 3 kilo sledge!!! :P ) My friend is not a blacksmith, although is a very skilled and competent metalworker, (among other things). He is atm restoring an old bedford lorry, and has a fleet of hgv's, mostly vintage but of all sorts!! He lives near marsworth. I lived in a narrowboat on the canal along there for a while, there is a forge just at Bulbourne, I think it's an old British Waterways yard, but I could be mistaken, was about 7 yrs ago, but I wasn't smithing at the time as I was pretty pregnant!!! Quote Link to comment Share on other sites More sharing options...
GNJC Posted February 22, 2012 Author Share Posted February 22, 2012 Ha! I'll be sure to put a large, red, block capital note on my 'instruction sheet' advising against use with power hammers. :) Quote Link to comment Share on other sites More sharing options...
GNJC Posted February 23, 2012 Author Share Posted February 23, 2012 Here, as promised, are pic's of the stand I use for my regular block and the add-on that allows use of the new block too. As you can see, I like a waist-height for working. I used 2"x2" because I was given a lot for nothing, but any size from that up would probably be fine. I prefer wood stands to metal ones. Quote Link to comment Share on other sites More sharing options...
Jonny Foreigner Posted February 25, 2012 Share Posted February 25, 2012 Hi Giles, From my perspective I am OK with cast iron - I will be using the block for thin plate work so lighter weight hammers will be the order of the day for me. A lot of what I have produced in the past has been cold worked using formers held in a cheap 6 inch cast iron machinist bench vice without problems and I know they have a name for breaking if used in this way. A waist high oak beam off cut to is awaiting to sit it on which will support it entirely so would avoid the situation Owen describes. I needed to get rid of a large wood burning cooker once (really awful french thing - worth nothing more than scrap, before I get berated) and took a sledge to it, very easy to break but the metal was only 1/4 inch in places so not surprising. I would of thought the biggest issue on a heavy block such as this would be chipping but again, for me using hot thin plate, can't see it being an issue. If it was the kind of block you show in the second picture above I would possibly be more wary. Good to talk to you on Tuesday even if it was a really crappy line, pity we could not meet up but c'est la vie. Took the kids to Bath on Wednesday and showed them The Baths. Look forward to seeing the finished product. Guy Quote Link to comment Share on other sites More sharing options...
GNJC Posted February 28, 2012 Author Share Posted February 28, 2012 Hello Guy, Yes, I agree that some of the 'industrial' blocks do have vulnerable points; if there were not already so many of them around, I would think about having a go at designing an improved version. As I explained to you on the 'phone (it was a bad connection), and earlier in this thread, I do not think that the use of cast iron will be a problem. Well, my attempt at a destructive test will happen on tomorrow or Thursday, which will be interesting. If it is particularly so, either in breaking or withstanding my whacks, I'll put it on disks and send one out with each block! Quote Link to comment Share on other sites More sharing options...
GNJC Posted March 1, 2012 Author Share Posted March 1, 2012 This afternoon I took out the cast iron block along with several large hammers and proceeded to bash it while being filmed. I hit it while it was standing upright, to allow me a good target and to show how hard I was hitting it by its movement after each strike. Starting with a 6½ lb short handled hammer, I whacked it in what I think is the most vulnerable place – the top corner of the thinner part at one side of the ‘swoosh’. The result was that the block went flying but suffered no damage other than a dent / smear; several more hits and the result was the same. A short handled 14 lb hammer was next. The block jumped a bit further, another smear / dent but no other obvious damage. More blows, same result. Lastly, a long handled 8 lb hammer was used several times; with a good swing it, too, sent the block flying but did not break the block. Just more dents. So, having done that I decided to set Colleen’s mind at rest; I held the block at chest height and dropped the block – flat faced – on to a concrete slab. No visible effect, so I did it again, same result. I think it should dispel any fears that people have regarding the suitability of modern cast iron for such a block. Youtube link available if I can get it to work, if not I'll send a disk with each block sold. Having just finished all that, I received a ‘phone call from the head foundryman. They have done a run of castings, but… each one has ‘rubbish’ (politer than the word he used) to a greater or lesser degree on the flat part of the upper face. He said he thinks this can be fixed by using metal at a slightly higher temperature; he’ll do another run at the start of next week, if that does not succeed he’ll try it hotter still. (I don’t know how a higher temperature will improve things, but clearly he’s the expert, not me.) Irritating, but I’ve seen the quality of stuff they turn out, so I think it is worth waiting. But, if it still does not cast perfectly after the heat ‘experiments’, I shall start thinking about seeking outside expert advice. Any comments / advice regarding this matter from those who know about casting will be most welcome. Quote Link to comment Share on other sites More sharing options...
beth Posted March 1, 2012 Share Posted March 1, 2012 thanks for your efforts giles, it will come together - wish i could offer some better help really, but all i can say is keep the faith - the blocks will be brilliant - the wait is no problem, it has to be done right :) Quote Link to comment Share on other sites More sharing options...
pkrankow Posted March 2, 2012 Share Posted March 2, 2012 Hotter should flow better and draw from the risers nicer because the mold will be hotter. I am no expert either. You beat the tar out of that thing! Did it feel good? Phil Quote Link to comment Share on other sites More sharing options...
tzonoqua Posted March 2, 2012 Share Posted March 2, 2012 Can't wait to see this vid giles!!! With regards to the foundry, it's always worth waiting for the niggles to be smoothed out. Quote Link to comment Share on other sites More sharing options...
GNJC Posted March 2, 2012 Author Share Posted March 2, 2012 I have managed to get a video uploaded onto Youtube. However, the quality is not brilliant because my attempts at uploading my original footage failed, forcing me to convert to a more basic type of file. I’ll send the original, higher quality, footage out with the blocks. Apologies if the filming seems rushed; I was doing it on a concrete slab that I didn’t mind breaking, but having to finish it quickly before the postman arrived. Quote Link to comment Share on other sites More sharing options...
Dave Budd Posted March 2, 2012 Share Posted March 2, 2012 i don't think you were trying to break it :P Quote Link to comment Share on other sites More sharing options...
GNJC Posted March 2, 2012 Author Share Posted March 2, 2012 Well, I didn't take it back to the foundry today so it's still here. I'll do another film if you like, instructions please Dave... <_< Quote Link to comment Share on other sites More sharing options...
Dave Budd Posted March 2, 2012 Share Posted March 2, 2012 was only kidding :) I had it in my head that you had properly layed into the block with a sledge, like trying to smash concrete. I don't know if having the ground under the line of strike will make a huge impact on the block (it seems t be pretty tough stuff!), but if somebody were to try using it with a sledge hammer then they will have a solid stand beneath the blow. Like you say though, its pretty much a moot point since if the swage is subjected to 'proper use' then it shouldn't be subjected to these stresses. The fact that it survived unscathed a drop and some errant side blows proves it to be up to fool proof (dare you try to make it totally idiot proof? ie the dumbass youtube testers who often wear hockey masks?) Quote Link to comment Share on other sites More sharing options...
GNJC Posted March 2, 2012 Author Share Posted March 2, 2012 No problem, but I take your point Dave. I didn’t do any roundhouse hits because I was trying to take that top corner off. Bear in mind its weight of 79 lbs / 36 kg and you’ll appreciate it was hit fairly hard to move it. Nonetheless, I shall ‘properly lay into it’ tomorrow and also whack it while flat on the ground (if it is still in one piece). It will probably break up then; I was surprised that it didn’t crack / break up when it was dropped flat. Assuming Youtube is compliant I’ll post the video once taken. Quote Link to comment Share on other sites More sharing options...
Dave Budd Posted March 2, 2012 Share Posted March 2, 2012 I guess I'm just one of those people that take the phrase 'destruction testing' to it's limit :ph34r: I would try the things that replicate likely use-damage first and then move on to more and more severe attacks. I think if I were to pick a weakpoint ot strike I would stand it on end so that the nike swish is uppermost and strike a blow from in line with the length of that side off towards the smaller corner (so the force is directed towards the outside but still has ground beneath it). I'm definately not saying that your tests thus far don't show how tough the block is (If I thought that then I wouldn't still want one!). Just playing devil's adovcate really. Also, since you are returning it for melt down anyway, You may as well have fun and see what it will take! Who knows, it might help to sell a few blocks in the future! Quote Link to comment Share on other sites More sharing options...
GNJC Posted March 2, 2012 Author Share Posted March 2, 2012 Right ho, I'll start like that and do it until breaks or I'm too knackered to carry on (good point about giving it 'support'). Following that, I'll hit what is left in various positions, aiming to break it from the centre outwards while being supported from underneath. We shall see... Quote Link to comment Share on other sites More sharing options...
pkrankow Posted March 2, 2012 Share Posted March 2, 2012 I like the plan. It is good to know the limit, even if you demonstrated it isn't delicate the first time. Phil Quote Link to comment Share on other sites More sharing options...
beth Posted March 3, 2012 Share Posted March 3, 2012 dont hurt yourself giles!! Quote Link to comment Share on other sites More sharing options...
GNJC Posted March 3, 2012 Author Share Posted March 3, 2012 Hello all, there were requests for harder hitting, so this afternoon I gave the block some serious whacking and did indeed manage to break a piece off. Strength proven. The pic' at the bottom was taken afterwards. Enough said & done! :) Quote Link to comment Share on other sites More sharing options...
Jonny Foreigner Posted March 3, 2012 Share Posted March 3, 2012 Hammer with a saw cut in the handle and a rubber mallet... :D I could understand where Dave Budd was coming from however from my perspective I'm happy. Take a "grasse matinée demain matin" Giles Quote Link to comment Share on other sites More sharing options...
pkrankow Posted March 3, 2012 Share Posted March 3, 2012 I think that qualifies as unreasonable abuse. Phil Quote Link to comment Share on other sites More sharing options...
beth Posted March 3, 2012 Share Posted March 3, 2012 Ha! yeah, please stop now giles, im starting to feel like i should step in and take that sledge off you :0 Quote Link to comment Share on other sites More sharing options...
eric sprado Posted March 4, 2012 Share Posted March 4, 2012 Any tool we have can be broken. "Why do it?????" Committing waste is not a part of my frugal upbringing and way of life. I invite most to my shop to play. You may come but keep your hands off the sledge hammers. Quote Link to comment Share on other sites More sharing options...
Cross Pein Posted March 4, 2012 Share Posted March 4, 2012 Wow poor guy - You're not hitting it hard enough! Your hitting it too hard! I think you have a nice block there and I hope you sell a lot of them. Bill Quote Link to comment Share on other sites More sharing options...
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