Two things; if you can have the casting in the drag it's much better because if you have a casting in the cope both hydrostatic pressure and gravity will be working towards forcing the cope away from the drag allowing the molten metal to leak out. Secondly, if you are casting metal and have the capability to machine your castings you should place your riser directly in contact with the thick part of the casting that you are trying to prevent from shrinking. Remember, cardinal rule; the risers must be filled with the hottest metal so that when the casting is cooling the riser will remain molten and feed the casting where it needs it. Enjoyed the video mark! Sweet handrammer. You should get some nice ramming done that way.
Hi Sandrammer, your my number two site for casting after martins and it good to see that your following Mark who is a good site. in regard to your comment about "pressure and Gravity", I believe it is unfounded (no pun intended). From a structural engineers point of view (see Catcam Group) I view the dynamics of both the hydrostatic pressures and gravity acting identically at the parting line between the Cope(top) and the Drag (btm), so there will be no difference in the forcing of the two part of the mold, so no difference in the leakage, for this reason. I am not say there is no difference in leaking, but only that there will be no difference in leaking as a result of gravity nor hydrostatic pressures. To explain, When calculating the hydrostatic pressures at a depth, it is a function of the depth of the fluid from the free surface to the point being measured and the density of the fluid and of course gravity. Both gravity and the density remain constant so it is only the depth that is a variable that affects the hydrostatic pressure. The hydrostatic pressure at the depth of the parting line determines the force created that acts in separating the cope from the drag. now as long as the mold geometry is not varied, in either the cope or the drag, which we are not considering, the depth to the parting line is fixed and also a constant, irrespective of whether the pattern is in the cope or the drag. Therefore the actual hydrostatic pressure that forces the cope and the drag apart is the same regardless whether the void is in the drag or the cope, this excludes the second order slight change in weight of the cope as i has less sand in it if the void is located in the cope. In any case as martin can be seen doing, just place some weights on the cope to help keep the two together. I have used school case latches between the cope and drag to prevent the two separating but on large slender copes there is a tendency for the sand to bulge up irrespective of how well the cope and drag are latched together. in these situations the placing of weights on the sand surface works a treat.
Here's two more things. I totally forgot to weigh the flasks down to prevent the hydrostatic pressure from forcing the boxes apart. I also had a bit of a brain fart when I put the riser on the opposite side of the casting cavity. I don't know what I was thinking there. However the casting turned out OK and I factored in the shrinkage when I designed the pattern. I have still to have a go at casting the handwheel for the Bridgeport quill and I made a mental note to take your advice to top off the riser with the hot metal from the crucible. I truly appreciate the feedback and I take it all on board but I must say I don't have much of a plan when I do these videos. It really is just a fly on the wall approach and I sometimes regret that I don't edit out my failures but authenticity comes with a cost! 😀 Regards, Mark
@@Preso58 , If the castings turn out ok, fine but if they don't you now have things to try to make your castings come out better. Keep up the good work!
@@Preso58 Hi Mark, please don't regret editing out the failures in your videos. The successes as well as the failures are both educational for both the novice as well as the experienced. the various points of the videos, of either description, are talking points, that open the forum to airing the pros and cons of the various points of view. There will be many different views and everyone can take away the perspective that they perceive at the most suitable for their way of working. not many people are positioned to produce the videos but they can help by providing a layer of expertise over the various comments made. I feel that your modus operandi is at a good balance so keep it going. good woek.
@@Preso58 Keep up with the warts and all approach Mark as everyone learns that way. If you only showed successful castings no one would learn anywhere near as much or have such interesting discussions in the comments section.
Thanks Mark! My video next week will be discussing runners and gates but will also be casting in the cope. So thanks for the nice segue 😄 One note, we want to keep the sprue full. Now that in actuality may be the same thing as keeping the metal to the top of the basin but the goal is to keep the sprue full so we can, as you said, keep from sucking air down the sprue. In my opinion, casting tall parts in the cope is the way to go. As you said, having the metal fall into a deep hole in the drag causes turbulence. Having said that, I cast plenty of stupid little plaques in the drag. I do this because it's just plain easier to cast the letter side down. But I'll justify it with the fall entering the part is insignificant so the resultant turbulence is pretty small as well. Great job pointing out that we want to keep the metal entering the part as calm as possible.
Perry, I think that was the first time I had seen the metal flow accelerate as the sprue filled up. I was totally focused on trying to watch for that moment and speed up the pour. Easier said than done though. I only have a little brain and by the time my eyes saw the metal suck down the sprue my hands took a while to catch up. Maybe it is like muscle memory and if you do it often enough it just becomes automatic. Regards, Mark
@@Preso58 Hey, you don't need to explain to me, It seems to still catch me off guard even though I'm expecting it. I think you're right, it is a bit of muscle memory or at least something like that and it does seem to require us to be looking at multiple things simultaneously. "little brain"... pish...
Hi Mark, I am very much into learning about foundry work at the moment so thank you for the tips in Ol Foundry Man and SWdeeb and I've just notice the other guys you mention in the video description. Plenty for me to watch now. Take care Paul,,
ol foundyman is a great guy. Of course he would be, as a fellow Australian. He definitely knows his stuff for sure. Love the humor at the end of the video. Sounds like you have fun making your video,s. Looking forward to coming back for the machining.
More machining coming up next week. I have just about finished the bracket for a worklight. I did the powdercoat today and it should be on the mill tomorrow. Regards, Mark
Good luck Gary! It is so rewarding when you finally reveal a nice casting. For me at least, I can now make things that I would find very hard to do any other way. A fabricated part always looks a bit rubbish along side a nicely proportioned and machined casting. Regards, Mark
Nice work Mark and another interesting video for the collection. I vote that you keep doing the warts and all approach as there are many lessons to be learnt along the way.
Very nice and clean castings....Sigh...one day I will get around to casting something!...In the meantime I appreciate all the lessons I receive on how to go about it the right way. Nice workshop by the way! Keep up the good work!
Thanks for that. I still have the very first castings I made which were a pair of lathe dogs for mounting work between centres on the lathe. Nobody was more surprised than I was when they were retrieved from the mould. They were almost as good as the castings I am now doing 8 years later. I guess I am a bit more efficient at the process now but it's not as hard as I imagined it would be. Casting iron is still a distant goal but I would like to do it one day. Regards, Mark
Mark. I also had trouble remembering which was which. After making many moulds I learned that the drag is the first box to be rammed up and you tend to drag it across the bench when you turn it over to assemble the cope. Regards, Mark
Hi Presso. Keep up the Vids. I’m based in Sydney and want to start casting some Ally to machine. Trying to save money over buying chunks of it. Where do you buy the sand and the stuff that makes it sticky amd harden please? Any tips be appreciated
Hi Mark, I believe it is generally better to have the riser/feeder on the runner side of the casting, rather on the opposite side. The metal cools when it traverses the sand mold and the material that fills the riser when it is on the far side is cooler and will not feed as well as if it was hotter and more fluid. The riser material needs to stay fluid to feed the shrinkage of the casting, so should be part of the last bit of metal poured.
Charles, yes, that was a big mistake. I was taken to task by Martin for my very poor choice of placement of the feeder. I don't know what I was thinking. However, I now know what not to do and that's the thing about the pursuit of knowledge. For every setback there is a teaching moment. Should I have just edited that whole debacle out? I did consider it but it highlighted the point that the casting is still usable it just needs a bit more work to make it serviceable. I dodged a bullet in that the shrinkage was factored in at the design stage of the pattern. Regards, Mark
@@Preso58 Hi Mark, as I commented above , please include all the blunders in the videos and don't edit them out, as they are very useful for airing commonly made blunders that all the newbies should be aware of. I appreciate he format that you provide, please keep it going.
Very satisfying to watch. How thin can you make the castings? Are there thin wall metal casting and casting finishing guidelines available for the complete amateur to duplicate a motorcycle engine side cover by this method or do you have to pressurise the metal going into the mold to fill out the voids? The parts you made are fit for purpose and can be cleaned up with a large flat auto body file and a Linishing belt sander on a bench grinder (Scotchbrite belt for polishing), no machining required for what it is. How would you finish more complex shapes without a vertical mill?
The problem with really thin walled parts is that the molten metal will chill and solidify before it completely fills the mould. That's why most thin castings are pressure or gravity die cast in heated dies. Olfoundryman has an excellent video on the process here th-cam.com/video/MuifHNq38NE/w-d-xo.html I have had some success with castings in sand moulds with wall thicknesses of around 4mm. Having sufficient height in the top box (cope) does help with filling the mould and also the size and placement of the feeder is important too. The feeder will keep a reservoir of molten hot metal close to the gate of the mould cavity so that as the metal shrinks it is topped up to avoid local shrinkage. Having said all that, it is often the case that you just have to experiment. I will often have to cast a single part three times before I get any success. There are lots of other variables too. like how hot your metal is, how wet your greensand is and how quickly you can get the metal into the mould. If your casting comes out relatively clean you can do most of the cleanup with files and scotchbrite discs. If you have a large flat surface like a piece of old kitchen benchtop and a big piece of coarse sandpaper (large sanding discs or sanding belts are good) you can rub any mating surfaces on the sandpaper to render them almost flat. After that you probably really do need a milling machine or at least a good drill press for drilling out bolt holes and/or reaming bearing holes etc. Regards, Mark
Greg, sorry but I got his name wrong. It's Andrew Martin th-cam.com/channels/FpsAJppHZPEiPQruNfhGgA.html I haven't seen any uploads from him for a while. I hope he's OK. Regards, Mark
Good Show Mate...as always. So the cat was harmed after the video was done. Just funnin'. I will probably never do any casting. I'm somewhat clumsy. I would probably be wearing the casting metal. But I cast vicariously with Mark. I love it and it cuts down on hospital visits. Your reputation is entirely intact.
That gag about the whole cat thing is just my way of saying how foundry work is one part black magic and one part science. It seems like every time I think I've got it figured out I am humiliated by another failure. Regards, Mark
@@Preso58 Mark, people who do stuff have more failures than people who don't do stuff. No reason to be humiliated. If you weren't doing whatever you were doing, you'd just being doing something else. Be well.
Look like some nice, clean castings 😁. Probably should avoid barrying a cat like that... ever see pet cemetery? Some serious hoo doo there 🤣. Great vid, Mark. Cheers!
Hi Mark Great video very helpful Where did you get the crucible you used in the video ( i have copied your furnance just need to get it up and running) Cheers Tim
Tim, I purchased my crucible on Ebay. It is an A8 and is supposed to take 8Kg of metal although they don't stipulate what sort of metal. I only paid $29 for it which may have been a mistake since they are now selling for around $90. www.ebay.com.au/itm/8KG-Graphite-Crucible-Smelting-Melting-Gold-Silver-Copper-Casting-Furnace-HOT/164303664266?hash=item264142f48a:g:Zd0AAOSwU9NfJvjh Regards, Mark
@@Preso58 The "8" is indeed the capacity of the crucible in Kg of pure copper brim full. Beware Ebay crucibles tend to be a bit er well ordinary.... Martin
Joel, the greensand is pretty porous and the trapped air is able to escape easily. If the casting were very large and the flask had to be very deep it would help to form vents. Regards, Mark
Generally, metal is poured into a mound as rapidly as possible so as to heat the mold evenly, and to prevent the metal from cooling too quickly, locally, as the metal is poured. The mold itself absorbs heat from the metal. A slow pour can cause stratified temperatures throughout the metal, causing stress. Thin parts, of course, are less affected. But thicker parts, and ones with complex shapes will be more affected. It’s one reason why large castings were often left out for up to a year before being machined, and then sometimes left out again for weeks after being rough machined.
I recall seeing rusty cast iron bathtubs sitting in an open field beside a factory where they were eventually enamelled. This was at Metters in Brisbane back in the 70's. The operator told us that the iron had to season before it went into the enamelling oven. However, there is some disagreement in the home or DIY casting community about how big the sprue should be and how quickly or slowly the metal should enter the mould cavity. I must say that I have adopted the slow and steady regime and I can report that my castings have far less porosity than they used to. I still have the odd disaster where the metal freezes before filling the cavity but it's a bit of a balancing act. I hope to learn a lot more about the process. It's fascinating and frustrating in equal measure. Regards, Mark
True. The bigger the spruce the faster the pour. But often there’s a need for more than one exit. I found that having a greater area for the exits makes the pour more reliable. This is as much art as science, though it’s amazing how industry has been able to make millions of identical objects through this primitive process.
Luv those shaky old hands, I have had a set of them installed as I have gotten older ?? Can be a bit frustrating, but just another thing you have to workaround as you get older ? I always remind myself of the 'old saying' that I heard from most of the old fellows when I was an apprentice, " Youth is wasted on the young" ? Didn't appreciate it when I was young, but sure do now ???
Gary, the shakiness is manageable but I now find that I am having to deal with a severe lack of flexibility in my fingers and hands. I ran into an old friend who was an avid clock collector and restorer. He had to give up on his cherished hobby because he could no longer manipulate the delicate tools required to repair clock movements. His rather frank observation was that he now has more time to observe and appreciate the beauty of his clocks. Having said that I also recall talking to a model engineer who built two large scale traction engines despite being a paraplegic. He worked entirely from his wheelchair in a modified workshop. We just have to learn to adapt. Regards, Mark
Mark, I thought that Martin recently did a video which included pointing out that the "10 mm" of a pouring basin was the depth from the top surface of the sand to the top of the weir, not the height of the weir. Or do I have that bass-ackward? Either Olfoundryman or Sandrammer talked about what I'm trying to say here. Was that your neighbor's cat? ;) I'm looking forward to seeing the machining, finishing, & installation of these parts!
I am sure that Martin, stated that it was the height of the weir from the base of the basin. Also in regard to Marks casting the second cast, there was no need to have the running go across the whole pattern as the pattern void would have carried out this function and would have resulted n less material to machine and less shrinkage.
Bob, I commented to Martin that the whole 10mm thing was confusing because he tends to place his camera directly over his workbench so it was difficult to see whether he meant the weir was supposed to be 10mm from the top of the basin or the bottom. He did do a follow up video where he stipulated that the weir was meant to be 10mm from the bottom of the basin. Our neighbour has no cats. Just two slightly asthmatic English bulldogs. Regards, Mark
G day mark this is just a thought but if you can 3d print the moulds for casting why not 3d print a pouring basin that you can ram the sand around rather cutting in as a second operation That way you can get consistent basin geometry that will allow for observation and improvment of the design
I actually have a 3DP pattern for a sprue and basin but the problem is that you would need to have different patterns for different depths of flasks. Also the pattern for the basin would end up very close to the edge of the cope and it would be hard to ram the sand consistently so close to the edge. There is also the issue that the top of the basin is bigger than the sprue so the sand can end up badly compacted directly under the basin. Many DIY foundry operators use 3DP patterns for gates, runners and risers but I don't find it much of a problem to hand cut these details. They don't have to be pretty since they end up as scrap to be remelted anyway. Regards, Mark
@@Preso58 all good I have not cast anything my self it's on the list of skills to acquire it was just the thought I had while watching your video this morning But your reasoning is sound thank you for your time
Craig, I am a big fan of Clarke and the Windy Hill Foundry. I am a regular viewer now. He does some amazing stuff with iron which is still the holy grail for me. Regards, Mark
Yes, I must try that. More often than not though, the charring comes from overflowing the basin as the riser fills or when something gets blocked up. Even though your eyes see the metal overflowing the hands just keep pouring the stuff in. The brain suddenly kicks in and instruct the hands to stop doing their thing but it's too late and your flask is now on fire! I wish I had some sexy cast aluminium flasks like Olfoundryman has. Regards, Mark.
Mark if you put strips of metal such as 1" X 4" around the sprue and riser pouring basin etc. the flow will stop and save your flasks. I also recommend weights to prevent lifting or run out. I find the aluminum flasks are too heavy for my liking Cheers Gene
Hey Presso..What sort of 3D printer and software do you use for printing your patterns..I’m wanting to get one for my shop but wasn’t sure which way to go
Gary, I have a Creality Ender 3 printer and I use Cura as my slicing software. The Ender 3 is a good entry level printer for the price and there is plenty of support for the hardware and upgrades are readily available. Cura is also free and it has regular updates Regards, Mark
@@Preso58 Thanks Mark... I was leaning that way or even the later Ender 5.. seems like it is very similar to the Ender 3 with a bigger build area and a few other fine tuning things... Many of the Ender 3 Mods will also fit the the Ender 5 as well.
One of the enjoyable things about your videos is you often include “experiments” and the result of same. Didn’t make much difference this time and that’s good to know, too.
Glenn, just about everything I make is a prototype so experimentation is a requirement for getting the job done. Things don't always go to plan but that makes for a better learning experience. Thanks for watching. Regards, Mark
Actually, maybe I misunderstood your question. I don't use any forced air draft on my furnace. If you were referring to the air gun I used to clean out the mould cavity it is run at around 5 PSI. Regards, Mark
I wish I could say there was a definitive methodology but every time I think I have the process sorted out I see some example that goes against the accepted wisdom. Sigh!
Nice work Prezzo! One note, as I understand the runner should be about the same cross sectional area as the bottom of the tapered sprue. Yours seem a bit bigger. 🙂 Just another thing to remember 🤣
No, I still use it. Many years ago, before I found out about the work done by Olfoundryman and SWDweeb, I was using a straight, large diameter piece of copper pipe to cut my sprues and although it worked I found that a lot of my castings had porosity and sand inclusions. Since adopting the tapered sprue all those problems went away. The other thing that Martin (Olfoundryman) encouraged me to do was to buy good quality ingots for my castings instead of melting scrap. This has also made a huge improvement to the machinability and strength of my castings. Regards, Mark
Believe me when I say it's a rabbit hole you don't want to go down unless you are in desperate need of some stress and disappointment. Not to mention the danger and serious risk to life and limb. Still, a man's gotta have a hobby! Regards, Mark
Ray I must say that I don't normally put my head on camera ( I have a good head for radio). I also noticed that I was looking at the monitor but you will see in my next video that I have addressed that particular rookie error. Regards, Mark
There are many other very knowledgeable practitioners in the metal casting community. I tried to name them all in the video description. These are just the ones that I have learned from. I am sure there are many, many more. I started out as a rank amateur and I still feel like I am a long way down the learning curve. Regards, Mark
Two things; if you can have the casting in the drag it's much better because if you have a casting in the cope both hydrostatic pressure and gravity will be working towards forcing the cope away from the drag allowing the molten metal to leak out. Secondly, if you are casting metal and have the capability to machine your castings you should place your riser directly in contact with the thick part of the casting that you are trying to prevent from shrinking. Remember, cardinal rule; the risers must be filled with the hottest metal so that when the casting is cooling the riser will remain molten and feed the casting where it needs it. Enjoyed the video mark! Sweet handrammer. You should get some nice ramming done that way.
Hi Sandrammer, your my number two site for casting after martins and it good to see that your following Mark who is a good site.
in regard to your comment about "pressure and Gravity", I believe it is unfounded (no pun intended). From a structural engineers point of view (see Catcam Group) I view the dynamics of both the hydrostatic pressures and gravity acting identically at the parting line between the Cope(top) and the Drag (btm), so there will be no difference in the forcing of the two part of the mold, so no difference in the leakage, for this reason. I am not say there is no difference in leaking, but only that there will be no difference in leaking as a result of gravity nor hydrostatic pressures.
To explain, When calculating the hydrostatic pressures at a depth, it is a function of the depth of the fluid from the free surface to the point being measured and the density of the fluid and of course gravity. Both gravity and the density remain constant so it is only the depth that is a variable that affects the hydrostatic pressure.
The hydrostatic pressure at the depth of the parting line determines the force created that acts in separating the cope from the drag.
now as long as the mold geometry is not varied, in either the cope or the drag, which we are not considering, the depth to the parting line is fixed and also a constant, irrespective of whether the pattern is in the cope or the drag.
Therefore the actual hydrostatic pressure that forces the cope and the drag apart is the same regardless whether the void is in the drag or the cope,
this excludes the second order slight change in weight of the cope as i has less sand in it if the void is located in the cope. In any case as martin can be seen doing, just place some weights on the cope to help keep the two together.
I have used school case latches between the cope and drag to prevent the two separating but on large slender copes there is a tendency for the sand to bulge up irrespective of how well the cope and drag are latched together. in these situations the placing of weights on the sand surface works a treat.
Here's two more things. I totally forgot to weigh the flasks down to prevent the hydrostatic pressure from forcing the boxes apart. I also had a bit of a brain fart when I put the riser on the opposite side of the casting cavity. I don't know what I was thinking there. However the casting turned out OK and I factored in the shrinkage when I designed the pattern. I have still to have a go at casting the handwheel for the Bridgeport quill and I made a mental note to take your advice to top off the riser with the hot metal from the crucible. I truly appreciate the feedback and I take it all on board but I must say I don't have much of a plan when I do these videos. It really is just a fly on the wall approach and I sometimes regret that I don't edit out my failures but authenticity comes with a cost! 😀
Regards,
Mark
@@Preso58 , If the castings turn out ok, fine but if they don't you now have things to try to make your castings come out better. Keep up the good work!
@@Preso58 Hi Mark, please don't regret editing out the failures in your videos. The successes as well as the failures are both educational for both the novice as well as the experienced.
the various points of the videos, of either description, are talking points, that open the forum to airing the pros and cons of the various points of view. There will be many different views and everyone can take away the perspective that they perceive at the most suitable for their way of working.
not many people are positioned to produce the videos but they can help by providing a layer of expertise over the various comments made. I feel that your modus operandi is at a good balance so keep it going.
good woek.
@@Preso58 Keep up with the warts and all approach Mark as everyone learns that way. If you only showed successful castings no one would learn anywhere near as much or have such interesting discussions in the comments section.
Thanks Mark! My video next week will be discussing runners and gates but will also be casting in the cope. So thanks for the nice segue 😄
One note, we want to keep the sprue full. Now that in actuality may be the same thing as keeping the metal to the top of the basin but the goal is to keep the sprue full so we can, as you said, keep from sucking air down the sprue.
In my opinion, casting tall parts in the cope is the way to go. As you said, having the metal fall into a deep hole in the drag causes turbulence. Having said that, I cast plenty of stupid little plaques in the drag. I do this because it's just plain easier to cast the letter side down. But I'll justify it with the fall entering the part is insignificant so the resultant turbulence is pretty small as well.
Great job pointing out that we want to keep the metal entering the part as calm as possible.
Hit me up or let me know how to get in touch with you before you go doing that... there are much better ways of doing it than what you're being told.
Perry,
I think that was the first time I had seen the metal flow accelerate as the sprue filled up. I was totally focused on trying to watch for that moment and speed up the pour. Easier said than done though. I only have a little brain and by the time my eyes saw the metal suck down the sprue my hands took a while to catch up. Maybe it is like muscle memory and if you do it often enough it just becomes automatic.
Regards,
Mark
@@Preso58 no, it's just poor methoding. Check your email =)
@@Preso58 Hey, you don't need to explain to me, It seems to still catch me off guard even though I'm expecting it. I think you're right, it is a bit of muscle memory or at least something like that and it does seem to require us to be looking at multiple things simultaneously.
"little brain"... pish...
Hi Mark,
I am very much into learning about foundry work at the moment so thank you for the tips in Ol Foundry Man and SWdeeb and I've just notice the other guys you mention in the video description. Plenty for me to watch now.
Take care
Paul,,
ol foundyman is a great guy.
Of course he would be, as a fellow Australian.
He definitely knows his stuff for sure.
Love the humor at the end of the video.
Sounds like you have fun making your video,s.
Looking forward to coming back for the machining.
More machining coming up next week. I have just about finished the bracket for a worklight. I did the powdercoat today and it should be on the mill tomorrow.
Regards,
Mark
@@Preso58
Thanks for letting me know Mark.
Looking forward to watching.
All the best.
Peter.
Haha, poor cat... Castings look great! Nice shoutouts to 3 of my favourite youtube metal casters also.
I'd heard it was a dead donkey, or was that when you plant a fig tree, or was it both!
I have been getting the same 2 suspicious 'flixzone' replies as seen here on several of my youtube comments recently, from different posters. FYI
I am so interested into casting for myself and getting things made and ready. Soon, I hope, soon. Thumbs Up!
Good luck Gary! It is so rewarding when you finally reveal a nice casting. For me at least, I can now make things that I would find very hard to do any other way. A fabricated part always looks a bit rubbish along side a nicely proportioned and machined casting.
Regards,
Mark
Nice work Mark and another interesting video for the collection. I vote that you keep doing the warts and all approach as there are many lessons to be learnt along the way.
Thanks, will do!
Regards,
Mark
Pleasure to watch you do your thing, Mark!
Thanks for that. Trust me, I am getting better. I edited out a lot of bad words in that video.
Regards,
Mark
Very nice and clean castings....Sigh...one day I will get around to casting something!...In the meantime I appreciate all the lessons I receive on how to go about it the right way. Nice workshop by the way!
Keep up the good work!
Thanks for that. I still have the very first castings I made which were a pair of lathe dogs for mounting work between centres on the lathe. Nobody was more surprised than I was when they were retrieved from the mould. They were almost as good as the castings I am now doing 8 years later. I guess I am a bit more efficient at the process now but it's not as hard as I imagined it would be. Casting iron is still a distant goal but I would like to do it one day.
Regards,
Mark
Nicely done. You had a very clear methodologym thanks for sharing.
Interesting video Mark👍🏻 nice sticker in the background too, always amazes me where they pop up. Glenn
Thanks, I got yours in a job lot from John Creasey!
Regards,
Mark
Great video. Very instructive. Awesome links to other foundry channels. Mahalo for sharing! : )
As always very enjoyable video and lots to learn, thanks a lot for sharing 👍👍👍
Very well put together clip. Thanks for the links.
I don't know if it was my laughing or the cat scream that made our cat jump so at the end. : )
Love the humor.
I laughed when you mentioned Martin from olfoundryman TH-cam channel. I know Martin he’s a wealth of knowledge 👍
I am in awe of his skill and knowledge. He doesn't hold back if he spots me making a rookie error either!
Regards,
Mark
Nice video. It was cool to see all the steps that went into creating that. Funny end to the video too 😂
Thank you for the text translating cope and drag. I have watched several casting videos but always get confused by the jargon.
Mark. I also had trouble remembering which was which. After making many moulds I learned that the drag is the first box to be rammed up and you tend to drag it across the bench when you turn it over to assemble the cope.
Regards,
Mark
@Barry Manilowa OK Barry, I'll let this one slide, for now!
Some useful tips and the castings turned out well. Regards Kevin
Top job Mark (as always). Martin makes it look so easy and I know it's not.
No, it's difficult to get right first time. It always amazes me when I do get it right.
Regards,
Mark
Hi Presso. Keep up the Vids. I’m based in Sydney and want to start casting some Ally to machine. Trying to save money over buying chunks of it. Where do you buy the sand and the stuff that makes it sticky amd harden please? Any tips be appreciated
Well done Mark👌
Thanks Clarke.
I am grateful for all the tutorials I can get. I am still hoping to make it to the next level and cast some iron!
Regards,
Mark
Hi Mark,
I believe it is generally better to have the riser/feeder on the runner side of the casting, rather on the opposite side. The metal cools when it traverses the sand mold and the material that fills the riser when it is on the far side is cooler and will not feed as well as if it was hotter and more fluid. The riser material needs to stay fluid to feed the shrinkage of the casting, so should be part of the last bit of metal poured.
Charles, yes, that was a big mistake. I was taken to task by Martin for my very poor choice of placement of the feeder. I don't know what I was thinking. However, I now know what not to do and that's the thing about the pursuit of knowledge. For every setback there is a teaching moment. Should I have just edited that whole debacle out? I did consider it but it highlighted the point that the casting is still usable it just needs a bit more work to make it serviceable. I dodged a bullet in that the shrinkage was factored in at the design stage of the pattern.
Regards,
Mark
@@Preso58 Hi Mark,
as I commented above , please include all the blunders in the videos and don't edit them out, as they are very useful for airing commonly made blunders that all the newbies should be aware of.
I appreciate he format that you provide, please keep it going.
@@charles1379 I agree with Charles, keep the mistakes in the video.
Very satisfying to watch. How thin can you make the castings? Are there thin wall metal casting and casting finishing guidelines available for the complete amateur to duplicate a motorcycle engine side cover by this method or do you have to pressurise the metal going into the mold to fill out the voids? The parts you made are fit for purpose and can be cleaned up with a large flat auto body file and a Linishing belt sander on a bench grinder (Scotchbrite belt for polishing), no machining required for what it is. How would you finish more complex shapes without a vertical mill?
The problem with really thin walled parts is that the molten metal will chill and solidify before it completely fills the mould. That's why most thin castings are pressure or gravity die cast in heated dies. Olfoundryman has an excellent video on the process here th-cam.com/video/MuifHNq38NE/w-d-xo.html I have had some success with castings in sand moulds with wall thicknesses of around 4mm. Having sufficient height in the top box (cope) does help with filling the mould and also the size and placement of the feeder is important too. The feeder will keep a reservoir of molten hot metal close to the gate of the mould cavity so that as the metal shrinks it is topped up to avoid local shrinkage. Having said all that, it is often the case that you just have to experiment. I will often have to cast a single part three times before I get any success. There are lots of other variables too. like how hot your metal is, how wet your greensand is and how quickly you can get the metal into the mould. If your casting comes out relatively clean you can do most of the cleanup with files and scotchbrite discs. If you have a large flat surface like a piece of old kitchen benchtop and a big piece of coarse sandpaper (large sanding discs or sanding belts are good) you can rub any mating surfaces on the sandpaper to render them almost flat. After that you probably really do need a milling machine or at least a good drill press for drilling out bolt holes and/or reaming bearing holes etc.
Regards,
Mark
Another great video, Mark. I've been able to find all the channels you reference but Andrew Thomas' . Can you provide a link?
Greg, sorry but I got his name wrong. It's Andrew Martin th-cam.com/channels/FpsAJppHZPEiPQruNfhGgA.html
I haven't seen any uploads from him for a while. I hope he's OK.
Regards,
Mark
Good Show Mate...as always. So the cat was harmed after the video was done. Just funnin'. I will probably never do any casting. I'm somewhat clumsy. I would probably be wearing the casting metal. But I cast vicariously with Mark. I love it and it cuts down on hospital visits. Your reputation is entirely intact.
That gag about the whole cat thing is just my way of saying how foundry work is one part black magic and one part science. It seems like every time I think I've got it figured out I am humiliated by another failure.
Regards,
Mark
@@Preso58 Mark, people who do stuff have more failures than people who don't do stuff. No reason to be humiliated. If you weren't doing whatever you were doing, you'd just being doing something else. Be well.
Interesting informative video, Cheers!
Great job yet again mate, dead cat loved it.
Thumbs up if only for the cat at the end!
For a big mistake, it seemed to turn out well enough. Just extra cleanup to mill that ridge off, no?
That's it. The only damage done was to my reputation! 😁
Look like some nice, clean castings 😁. Probably should avoid barrying a cat like that... ever see pet cemetery? Some serious hoo doo there 🤣. Great vid, Mark. Cheers!
I read the book. It scared the living daylights out of me.
Regards,
Mark
Hi Mark
Great video very helpful
Where did you get the crucible you used in the video ( i have copied your furnance just need to get it up and running)
Cheers
Tim
Tim, I purchased my crucible on Ebay. It is an A8 and is supposed to take 8Kg of metal although they don't stipulate what sort of metal. I only paid $29 for it which may have been a mistake since they are now selling for around $90. www.ebay.com.au/itm/8KG-Graphite-Crucible-Smelting-Melting-Gold-Silver-Copper-Casting-Furnace-HOT/164303664266?hash=item264142f48a:g:Zd0AAOSwU9NfJvjh
Regards,
Mark
@@Preso58 Thanks Mark
@@Preso58 The "8" is indeed the capacity of the crucible in Kg of pure copper brim full. Beware Ebay crucibles tend to be a bit er well ordinary.... Martin
I think stirring the metal with a spoke is the equivalent of a dead cat. Good to see the use of a spoke.
Love it 😻
Would it help to have very small vents at the top of the highest features?
Joel, the greensand is pretty porous and the trapped air is able to escape easily. If the casting were very large and the flask had to be very deep it would help to form vents.
Regards,
Mark
Generally, metal is poured into a mound as rapidly as possible so as to heat the mold evenly, and to prevent the metal from cooling too quickly, locally, as the metal is poured. The mold itself absorbs heat from the metal. A slow pour can cause stratified temperatures throughout the metal, causing stress. Thin parts, of course, are less affected. But thicker parts, and ones with complex shapes will be more affected. It’s one reason why large castings were often left out for up to a year before being machined, and then sometimes left out again for weeks after being rough machined.
I recall seeing rusty cast iron bathtubs sitting in an open field beside a factory where they were eventually enamelled. This was at Metters in Brisbane back in the 70's. The operator told us that the iron had to season before it went into the enamelling oven. However, there is some disagreement in the home or DIY casting community about how big the sprue should be and how quickly or slowly the metal should enter the mould cavity. I must say that I have adopted the slow and steady regime and I can report that my castings have far less porosity than they used to. I still have the odd disaster where the metal freezes before filling the cavity but it's a bit of a balancing act. I hope to learn a lot more about the process. It's fascinating and frustrating in equal measure.
Regards,
Mark
True. The bigger the spruce the faster the pour. But often there’s a need for more than one exit. I found that having a greater area for the exits makes the pour more reliable. This is as much art as science, though it’s amazing how industry has been able to make millions of identical objects through this primitive process.
great videos mark
Luv those shaky old hands, I have had a set of them installed as I have gotten older ?? Can be a bit frustrating, but just another thing you have to workaround as you get older ? I always remind myself of the 'old saying' that I heard from most of the old fellows when I was an apprentice, " Youth is wasted on the young" ? Didn't appreciate it when I was young, but sure do now ???
Gary, the shakiness is manageable but I now find that I am having to deal with a severe lack of flexibility in my fingers and hands. I ran into an old friend who was an avid clock collector and restorer. He had to give up on his cherished hobby because he could no longer manipulate the delicate tools required to repair clock movements. His rather frank observation was that he now has more time to observe and appreciate the beauty of his clocks. Having said that I also recall talking to a model engineer who built two large scale traction engines despite being a paraplegic. He worked entirely from his wheelchair in a modified workshop. We just have to learn to adapt.
Regards,
Mark
Very bunny. 🐈 Not many people around the world are old enough to remember or know about the cat-tastrophe to control the feral rabbit invasion 🐇.
Mark, I thought that Martin recently did a video which included pointing out that the "10 mm" of a pouring basin was the depth from the top surface of the sand to the top of the weir, not the height of the weir. Or do I have that bass-ackward? Either Olfoundryman or Sandrammer talked about what I'm trying to say here.
Was that your neighbor's cat? ;) I'm looking forward to seeing the machining, finishing, & installation of these parts!
I am sure that Martin, stated that it was the height of the weir from the base of the basin.
Also in regard to Marks casting the second cast, there was no need to have the running go across the whole pattern as the pattern void would have carried out this function and would have resulted n less material to machine and less shrinkage.
Bob, I commented to Martin that the whole 10mm thing was confusing because he tends to place his camera directly over his workbench so it was difficult to see whether he meant the weir was supposed to be 10mm from the top of the basin or the bottom. He did do a follow up video where he stipulated that the weir was meant to be 10mm from the bottom of the basin. Our neighbour has no cats. Just two slightly asthmatic English bulldogs.
Regards,
Mark
G day mark this is just a thought but if you can 3d print the moulds for casting
why not 3d print a pouring basin that you can ram the sand around rather cutting in as a second operation
That way you can get consistent basin geometry that will allow for observation and improvment of the design
I actually have a 3DP pattern for a sprue and basin but the problem is that you would need to have different patterns for different depths of flasks. Also the pattern for the basin would end up very close to the edge of the cope and it would be hard to ram the sand consistently so close to the edge. There is also the issue that the top of the basin is bigger than the sprue so the sand can end up badly compacted directly under the basin. Many DIY foundry operators use 3DP patterns for gates, runners and risers but I don't find it much of a problem to hand cut these details. They don't have to be pretty since they end up as scrap to be remelted anyway.
Regards,
Mark
@@Preso58 all good I have not cast anything my self it's on the list of skills to acquire
it was just the thought I had while watching your video this morning But your reasoning is sound thank you for your time
Phhhh, dead cat. Nice one! You should check out "Windy Hill Foundry" too. He does cast iron but is a great resource.
Craig, I am a big fan of Clarke and the Windy Hill Foundry. I am a regular viewer now. He does some amazing stuff with iron which is still the holy grail for me.
Regards,
Mark
In the trade single sided patterns are known as "flat backs". Nice video.
I didn't know that. I'll add it to the knowledge bank.
Regards,
Mark
I know, I know its only been up for 41 seconds, but its another metal casting video from Mark. What's not to like?
To keep your wood flasks from being burnt try using a piece of steel (angle iron, etc) it will create a chill and stop the flow
Yes, I must try that. More often than not though, the charring comes from overflowing the basin as the riser fills or when something gets blocked up. Even though your eyes see the metal overflowing the hands just keep pouring the stuff in. The brain suddenly kicks in and instruct the hands to stop doing their thing but it's too late and your flask is now on fire! I wish I had some sexy cast aluminium flasks like Olfoundryman has.
Regards,
Mark.
Mark if you put strips of metal such as 1" X 4" around the sprue and riser pouring basin etc. the flow will stop and save your flasks. I also recommend weights to prevent lifting or run out. I find the aluminum flasks are too heavy for my liking
Cheers Gene
Hey Presso..What sort of 3D printer and software do you use for printing your patterns..I’m wanting to get one for my shop but wasn’t sure which way to go
Gary, I have a Creality Ender 3 printer and I use Cura as my slicing software. The Ender 3 is a good entry level printer for the price and there is plenty of support for the hardware and upgrades are readily available. Cura is also free and it has regular updates
Regards,
Mark
@@Preso58 Thanks Mark... I was leaning that way or even the later Ender 5.. seems like it is very similar to the Ender 3 with a bigger build area and a few other fine tuning things... Many of the Ender 3 Mods will also fit the the Ender 5 as well.
One of the enjoyable things about your videos is you often include “experiments” and the result of same. Didn’t make much difference this time and that’s good to know, too.
Glenn, just about everything I make is a prototype so experimentation is a requirement for getting the job done. Things don't always go to plan but that makes for a better learning experience. Thanks for watching.
Regards,
Mark
Dumb question but, how much psi are you using with the air blower?
John, the pressure is quite low, probably only about 5 PSI. Any more than that and you risk dislodging the sand grains.
Regards,
Mark
Actually, maybe I misunderstood your question. I don't use any forced air draft on my furnace. If you were referring to the air gun I used to clean out the mould cavity it is run at around 5 PSI.
Regards,
Mark
Looks good to me
Looks like either way works but after centuries of doing it the traditional way their must be a reason for putting the pattern in the bottom.
I wish I could say there was a definitive methodology but every time I think I have the process sorted out I see some example that goes against the accepted wisdom. Sigh!
Nice work Prezzo! One note, as I understand the runner should be about the same cross sectional area as the bottom of the tapered sprue. Yours seem a bit bigger. 🙂 Just another thing to remember 🤣
i guess it is pretty randomly asking but does anybody know a good place to watch newly released movies online?
I thought you have given up on tapered sprue
No, I still use it. Many years ago, before I found out about the work done by Olfoundryman and SWDweeb, I was using a straight, large diameter piece of copper pipe to cut my sprues and although it worked I found that a lot of my castings had porosity and sand inclusions. Since adopting the tapered sprue all those problems went away. The other thing that Martin (Olfoundryman) encouraged me to do was to buy good quality ingots for my castings instead of melting scrap. This has also made a huge improvement to the machinability and strength of my castings.
Regards,
Mark
I've watched enough guys casting stuff to know that I really want no part of it.. but I know if I really need to cast something I could pull it off.
Believe me when I say it's a rabbit hole you don't want to go down unless you are in desperate need of some stress and disappointment. Not to mention the danger and serious risk to life and limb. Still, a man's gotta have a hobby!
Regards,
Mark
@@Preso58 Pfft, Danger is all relative.
Here kitty kitty
Hey preso if you are looking for ideas to impress your subscribers watch this video on youtube, shank cam by Henry Davis, you will be amazed!
Please remember to look at the camera not the viewfinder LOL
Please remember to be nice - at all times.
Ray
I must say that I don't normally put my head on camera ( I have a good head for radio). I also noticed that I was looking at the monitor but you will see in my next video that I have addressed that particular rookie error.
Regards,
Mark
Wait! There's an Aluminum tree? Why hasn't anyone of the usual suspects mentioned that before? You named all 3 of them. 😳
There are many other very knowledgeable practitioners in the metal casting community. I tried to name them all in the video description. These are just the ones that I have learned from. I am sure there are many, many more. I started out as a rank amateur and I still feel like I am a long way down the learning curve.
Regards,
Mark
Just sent you an email Mark. Hopefully I can help remedy some poor information you've been given here.
Got it! I take on board any help I can get.
Regards,
Mark