Casting an aluminium gang tooling block for a small CNC lathe

[@jagboy69]

That's impressive! I only dork with ceramic shell, but understand the complexities of casting thick stuff. Why you don't have more people following your work is beyond me!

[@olfoundryman8418]

World, Yes, thick work is a bit of a pain particularly with aluminium where the long solidification times of thick work give plenty of time for gas to come out of solution even in well degassed metal! Why don't more follow me? I really would like to know but its one of those mysteries of YT that mere mortals like us are never mean to understand! But why Oh why do people who seem to spent their lives pouring metal over smarties or whatever - to what purpose I cannot imagine - get well over 500K subs. Sigh, life is what it is Iknow but whatever it is it is just not fair -:)... Martin

[@viscash3606]

I agree. It baffles me why 10k subs would rather watch some fool with no knowledge, or skill, FAIL, than watch a Master at work achieve the best casting results on YT

[@markfryer9880]

Perhaps Martin you should consider doing some of those stunts to draw more attention to your channel. I think you are bound to have an ant colony in your garden who could do their bit for the cause and get turned into artwork. If people are casting smarties and such, how about showing them how to properly cast them and also for true Aussie flavour see what happens when you pour Al over some toast with Vegemite and also do it as a proper casting. Cast an apple and an orange to show proper casting techniques. Mark

[@olfoundryman8418]

Mark, Yes, the idea of some stunt or other to attract attention has occurred to me. Any while I would not really consider it a debasement or a lowering - its just not me!. Incidentally the bloke did not actually cast smarties he just poured molten copper over some and just about anything else he could get his hands on too!! In truth I am not in the business of making videos, rather I make castings that have an end use and I make a video while I am doing it. this explains in part the irregularity of my video out put. I know that there are many who make videos and will make a casting (of anything it does not matter what) just as an excuse for a video commonly they produce regular and frequent videos. Incidentally I could no bring myself to destroy some of the food of the Gods - vegemite... Martin

[@olfoundryman8418]

ViScAsh, I think its to do with why one watches. Many people, just want to be entertained rather than to learn something or find out how to do something. Look at the popularity of "Lucas the spider" for example, absolute pure entertainment (cute too) and the view numbers are to die for...Martin

[@jeffcook6877]

Your work is ABSOLUTELY BRILLIANT sir. Thank you for educating us all in the foundry industry.

[@olfoundryman8418]

Jeff, Thank you for your comment, It is comments like yours that make the task of shooting a video then editing it and putting it up on YT worth the effort... Martin

[@tdubveedub]

Great information! I learn so much just from watching you and hearing your commentary on technique and material.

[@ashkira2]

Last month i watched lots of videos of people producing parts for the lathe, described in David Gingery's book. What a mess those parts were in comparison to your products! I bet, watching your videos will help me to avoid ALL of their mistakes. Great job, as usual!

[@markfryer9880]

You will still make mistakes, can't be helped as it's all part of being human. However watching Martin at work will show you the best way to do things rather than start with bad habits.

[@ashkira2]

Indeed, i'll do my own mistakes - that's the only way to learn something. But ... Casting from scrap of unknown nature, bad venting, improper placement of pattern in a mould, too large sprues, no pouring basin, steel crucible, no flux, no degassing, rough sand - that's faults i've noticed there after watching Martin's videos and reading a couple of basic books. Some casting of those guys looked like cheese!

[@mrgreenswelding2853]

ashkira2 well worth your time to watch these videos. He is fantastic!

[@olfoundryman8418]

Ashkira, I do not know what possess people to try and make lathes out of aluminium. Some one needs to explain damping capacity to them. Aluminium doesn't have much but cast iron has lots result aluminium lathes will shake and chatter cast iron ones wont Magnesium incidentally has very high damping capacity but I do not recommend trying to melt and cast it. If I have helped you even avoid just one mistake I am happy... Martin

[@olfoundryman8418]

Mark, Still make mistakes - sure will - I do it all the time. But trying to stop bad habits forming and to eradicate those that have is why I am on YT. (Rather conceited of me perhaps, but it is what it is😁).. Martin

[@viscash3606]

Another outstanding example of a true master tradesman and his craft - nice work !!!

[@olfoundryman8418]

ViScAsh, I don't know about "master tradesman" I have seen some moulders whose skill in some areas would put me to shame. People who could consistently get a finish like my best and do it using hard sand, mind you in my own defence their castings did tend to be a bit gassy and difficult to machine. But I will take the compliment - thank you for it...Martin

[@theonlybuzz1969]

My goodness, it was just like watching Steve Austin, the 6 million dollar man when you was using the pneumatic hammer /rammer with the slo motion, I was suddenly whisked back to my childhood. Loving the videos and greeting from 🇬🇧

[@olfoundryman8418]

Phil, You must be as old as I am 😊Steve Austin indeed! Greetings back from the great southern land.... Martin

[@KravchenkoAudioPerth]

As soon as I watched you turn the pattern I thought Oh boy! this will not be an easy thing to cast. You gave a great video on how to do it successfully Martin. I learned something new to. Even pros make mistakes! I learn more from fixing mistakes than from most other things. And watching you pull off a sound casting from a potential disaster was brilliant.

[@olfoundryman8418]

Kravchenko, The person who has never made a mistake has never made anything (ancient saying attributed to a bumbling old foundry man). Indeed, I too think that one learns more form mistakes than from successes providing of course that you rectify the mistake next time and thus learnt two things - how not to do it and how to do it. 😀! In truth we were lucky with that second casting in that the leak was small and chilled off and stopped before the cavity had drained to below the feeder. If the metal level had dropped to the cavity proper al would have been lost! (why has this font size changed - Sigh muysteries of YT and Bill I guess.... Martin

[@olfoundryman8418]

And now the font is right size again as soon as I hit reply - mysteries indeed... martin

[@KravchenkoAudioPerth]

Them who makes no mistakes makes no things! (Grammatical errors intentional of course! Apologies to 6th grade teacher Mrs. Wade. My other favorite saying is some people's minds are like concrete. All mixed up and permanently set. Mark

[@olfoundryman8418]

Mark, "all mixed up and permanently set" sounds like a few of the foundry types I have met over the years. Being "set in ones ways" is unfortunately a bit of a foundry trait. John Campbell refers to it as the insistence on using 6000 year old technology - he is right it is...Martin

[@WaltSorensen]

Very nice work. It's not often you see someone use a chill on KZbin (not often is probably an overstatement, it's more like almost never seen on KZbin).

[@olfoundryman8418]

Walt, I thought I answered this yesterday but no reply here so here it is again. I( I probably forgot to hit the reply button 😚 ) I never have seen chills used on YT, but of course I have not seen it all (who has?) It is a pity because they are very useful not only for work like this but for dealing with that isolated thick boss in the middle of a thin section. I have just today been machining some other slabs made this same way, these are in a piston alloy that is a bit gas prone but the slabs at least on the chill side are like billet solid as a rock! In an upcoming video I pull another trick using chills (sort of) so stay tuned. Chills are a very handy technique to have in ones tool bag...Martin

[@donniebrown2896]

The master at work!! I saw your comment on cast iron and I totally agree, the hobbiest should not even think about melting any type of steel, aluminum is one thing but when your working with a material that will make water explode and concrete burn it's a totally different ball of wax. Enjoy watching your mastery.

[@olfoundryman8418]

Donnie, You should try magnesium! I don't know off anyone on YUT who does - I sure the hell will NOT give it a try! You are right aluminium is pretty reasonable stuff to handle, you can spill it on the floor and maybe a bit of a half hearted bubble or two but no Bang. Even a slightly damp ingot mould is not to much of a problem (best avoided though!). Try either with bronze and watch out - hot bronze shrapnel all around the room and I guess iron would be as bad, so incidentally is lead I think it is the SG as much as the temperature that determines how bad it will blow. I am glad that you like the videos... Martin

[@donniebrown2896]

Olfoundryman Martin, back before I found your channel I had been scrapping electronics for the basics to sell to the "yard". Somewhere along the line I was introduced to melting aluminum in a homemade furnace. When you said that about the magnesium it reminded me of one guy that had mixed some scap magnesium with his aluminum without knowing. You can only guess what happened. Thanks for sharing what you know and do.

[@CulinaireZaken]

Thanks for these verry informative videos, Martin! I got in to fiddling with metal because of myfordboy years ago. Didn't always go well... After watching your videos for hours (and hours...) I get acceptablr castings most of the times! Well, usable enough for a chef with a hobby-shed... Thanks again!

[@olfoundryman8418]

Pieter, Hmm, "didn't always go well" To be honest I am not surprised - we each have our own methods and techniques - myford's and mine vary considerably. I like to think that mine are based on science, learning, and long practice. Keep at it for it sounds like you are on the right trail and thus with practice will come further improvement....Martin

[@larryschweitzer4904]

I subscribed after watching just one of your videos. I've learned a lot. Still a lot more to be learned. You do a great job of explaining. I've decided to put you into my comments on other sites. I cast outside so the weather is against me for the next 2 months. Nebraska, USA.

[@olfoundryman8418]

Larry, Thank you for the spreading of my channel name - I do appreciate it. Foundry is an area where there is always more to learn. The day I stop learning is the day they screw the lid down on the box. In this game you always have to be open to new ideas (sadly many are not) My grandfather spent time in Nebraska in 1895. and I do understand that the winters can be very cold and I guess its hard to pour moulds in the snow. 😏 Also of course casting outside means you have to set up every time - I am permanently set up with everything ready to go it - makes a big difference. I note that many people cast outside and I guess you just have to pick the days when the weather is suitable. I have to do that a bit too - its very difficult to cast when its 43 deg C Stick with it....Martin

[@winexport878]

Martin that casting finish is exceptionally good. You have a fan. Krishna

[@olfoundryman8418]

Krishna, Actually I did not use much of my fine facing sand on the mould for this casting, just a little on the tops of the "feet' of the casting and as a result most of the surface was formed by my backup sand so the finish is in reality somewhat rougher than I can achieve. Indeed if you look at the finish of the castings for the Oakland cars (the other video that you have commented on) where I used the fine facing sand all over you can see a much better finish. I am grateful for having another fan... Martin

[@prestonengebretson5043]

Trust me I am FOLLOWING!!!! Sir, thank you for your fine disortation on casting...I taught bronze casting investment type...and what you are providing here is Priceless!!!!! You have solved many of my aluminum casting problems in just watching for the past couple of days...my, my , my I look forward to viewing all of your works...

[@olfoundryman8418]

Preston, When I receive a wonderful comment like the one you have made here I get reinvigorated to make more videos. Such comments just make the whole process much more worth while. If I have managed to solve any of your casting problems I am well pleased. Thank you for your comment... Martin

[@headstocktailstock]

Yet another gem from "THE MASTER", your videos are priceless Martin, I learn something every time, btw I've just cast some decorative plaques & on your advice didn't ram the sand too near the letters & yess I didn't get a "double image" on the letters! thanks. Graham.

[@olfoundryman8418]

Graham,. I have often noticed that many people ram much to close over the top of the pattern. I always (well almost always) fil the box plus a little more before I do even the first ram. I am glad that the advice worked for you. There was no one to tell me I had to find out the hard way!... Martin

[@Frank-bh3cm]

Your wife is quite the trooper!

[@olfoundryman8418]

Frank, You had better believe it! Trooper indeed, but wait there is more - she gets on the end of the shovel and helps me reprocess the sand at the end of each casting day. Then she mans the broom and cleans up all, at a time when I am so dog tired I can hardly move. If I only did one thing right in my life it was marrying her!... Martin

[@trisrush9155]

Great video and beautiful castings as always. Thanks Martin, best wishes!

[@olfoundryman8418]

Tris, To be honest these castings are a bit on the rough side as regards surface finish as I did not use my fine facing sand all the way up the sides of the part, but , and this is the main thing, they sure looked very solid when machined... Martin

[@jamieclark7221]

Great job using the cast iron plate.

[@olfoundryman8418]

Jamie, It was actually a steel plate but "same man different hat". It is a trick worth keeping in mind as it does produce very sound fine grained castings I really must get some bigger plates though -:) ... Martin

[@JulianMakes]

very interesting that chill. also that air rammer is incredble! great casting.

[@olfoundryman8418]

Julian, Chills are a good trick when you want a very solid fine grained casting or when you have a very thick casting that would otherwise be difficult to feed. The air rammer is a great thing better on bigger moulds of course but it does a nice job and quickly too. Getting it was an interesting story of how we Aussies get ripped of by overseas companies. First price I got from an Aussie agent for a big US company was close to $900.00 including about $250.00 for freight eventually got a better brand for a little over $300.00 via Amazon including $16.00 for air freight. No wonder Bezos has done well!!… Martin

[@Toto-ko5on]

Thank you Martin for this video!

[@olfoundryman8418]

Toto, My pleasure mate...Martin

[@splint3048]

Excellent work as always.

[@olfoundryman8418]

David, Thank you for your comment... Martin

[@tobhomott]

Olfoundryman, Walt Sorensen already mentioned this earlier, but I can't think of another example on KZbin of the use of chills. Bravo! Nice save on that last mold too... :o)

[@olfoundryman8418]

Tobho, No, I can't think of an example of chills either. Its a pity as its a very useful technique, not only as I used it here but I have seen smaller chills moulded in to get things like isolated bosses on a casting nice and solid. In future work I will be using them to help get the crown of a very thick piston solid, and - currently underway - making a quick short life die for some gravity die casting work. Re the lucky save see my reply to Kravechenco...Martin

[@davidmilway7886]

I have printed a number of 3D patterns an my solution to to making a area stronger for the extraction screws is to print a small grid of 1/32" holes around the 1/8" hole, make them as deep as you like and this will give a stronger area.

[@olfoundryman8418]

David, The problem was that I did not tell the friend doing the 3D printing that I needed a stronger area for the rap point and extraction screw. He is a non caster and therefore does not know of such things. It was a lesson learnt by me in that I need to allow for the relative weakness of 3D prints by specifying a denser print where required - along the lines that you suggest. Overall though I have to say that while 3D printing of patterns is convenient and seemingly easy I do very much prefer patterns made in more "old-fashioned" ways. (I have a "tame" pattern maker on call) 3 D prints have that wretched layer structure which makes for difficulties in extracting the pattern from the mould unless very well finished and then PLA in particular does not finish well - it seems "gummy". I also note that sometimes 3D prints can warp/change shape over time.... Martin

[@hansolo5967]

I love that pneumatic rammer. Thumbs UP!

[@olfoundryman8418]

Han, Long story! I tried to buy a rammer from pneumatic Co in the US. They would not sell direct instead putting their local agent (AKA beehive pneumatics - come in and be stung) on to me. For a $315.00 in the US retail price rammer the local agent wanted - wait for it, $900.00 citing high freight ($250.00 est.) as much of the reason plus a lot of other film flam. I had worked for a local Co who imported from the US and well knew what was reasonable and what was not. I told the US Co a thing or two (they are in Chicago hint hint don't buy from them). I found one on Amazon a nice Japanese unit so quality is good and all up in my hands for $360.00 including freight of $16.00. I love it too, but it better suits larger work than I do....Martin

[@dfross87]

Would something like an air chisel (with a customised bit for ramming) be more suited to your scale of work, Martin? The thought just popped into my head as I was reading your comment.

[@olfoundryman8418]

Df, Someone did mention having tried this on the old BYMC forum many years ago, he claimed a measure of success. However I am not sure exactly how big that measure was! He had attached some sort of flat plate to the air chisel and was I think only using it as a final pat down of the top layer of sand before striking it off level with the top of the box. The big problem I see is that sand rammers have a large stroke - mine has a 3 inch stroke, and watching it in action its obvious that it needs this sort of stroke to compact the sand under it as loose sand to compacted sand is a factor of 3 to 4 at least. Air chisels of course have quite a small stroke, the one I have has perhaps a stroke of a few mm at most. Never stop thinking though, Its what keeps mankind moving forward - the next thought might be a real winner!...Martin

[@lawr46]

Amazing results, I'm always impressed by your work!

[@olfoundryman8418]

Law, Thank you I appreciate your support.... Martin

[@paulmuff9883]

Hi what is the stuff you’re putting on the risers after poring & what’s it for ? Manny thanks

[@olfoundryman8418]

Paul, The reddish powder I put on the feeders is called "Ferrux NF" it is made by "Foseco". It is an exothermic powder whose job it is to catch fire and generate a lot of heat so the feeders stay liquid for longer and are thus able to better provide feed metal for the solidifying casting below... Martin

[@Mistertbones]

Even though this video is a few years old, these were great castings. How long do you leave the metal in the sand before pulling out?

[@olfoundryman8418]

Mister, I pull them out and water quench as soon as the casting is just solid enough to handle. … Martin

[@Mistertbones]

@@olfoundryman8418 Thank you, Martin. You're a great source of foundry knowledge.

[@johnwp111]

Hi Martin, another great video on casting.

[@olfoundryman8418]

John, Glad that you enjoyed it..Martin

[@aga5897]

Awesome. Truly awesome !

[@AmalgmousProxy]

Love your keg on wheels squelching container. I'm going to have to build me one of those.

[@olfoundryman8418]

Amalgamous, Kegs are wonderous things, so useful, I have another that I use as my fuel container I pressurise it to 10 Psi to push the fuel to the burner. Those prone to a little elbow bending, and what foundry man isn't, do have a very strong belief that kegs are at their best when full!... Martin

[@clarencecherrone7914]

There are slicer programs that will allow you to change infill percentages in places.

[@olfoundryman8418]

Clarence, I don't have a 3D printer myself and I rely on a friend to do it for me (same friend who owns the Hercus lathes). Unfortunately his printer (a Robox) uses propriety software and is not capable of infill changes part way through a print, What you set the infill at in the beginning of a print is what you get all through. In an upcoming video (about a Bronze bitcoin for Swdweeb) I use a 3D print in abs from this printer. there is no smoothing and no painting of the print but the resultant casting while not perfect is quite reasonable.... Martin

[@MaturePatriot]

First use of a pneumatic rammer I've seen. Always wondered why no one used one. - What is the compound that you put on the riser immediately after the pour? - I enjoy watching a craftsman at his trade. Great work.

[@markfryer9880]

Exothermic reaction powder, used to help slow the chilling of the riser so that more of the metal is available to supply the casting as it cools and draws in more metal.

[@WaltSorensen]

The big commercial shops almost all use pneumatic rammers, some of their "shop tours" on KZbin show their floor guys using them. Some of those big commercial shop tour videos will also show production pattern squeezer machines the use a hydraulic press to compress the sand. (if your interested, I have a playlist of some random videos from around KZbin showing these shop tours I use for reference)

[@MaturePatriot]

Thank you.

[@olfoundryman8418]

Mature, Yep, that pneumatic rammer is a real goer. Most of my work is a bit small to use it to its fullest advantage but it sure does a nice job of ramming a mould, While still no doubt used they used to be much more common in foundries, these days most moulding is done on automatic machines - whiz bang one 4 foot by 3 foot by 18 inch high mould in 10 seconds 12 seconds if cores have to be added! Jobbing shops would be the most likely home for this type of device these days. Also good for making adobe bricks! The material added to the top of the feeder immediately after the pour is "Ferrux NF" it is made by "Foseco" it is an exothermic compound ( a bit like thermite) that catches fire and keeps the feeder molten for longer so it can better provide liquid feed metal to the casting - I would not be without it....Martin

[@jmhannnon]

You can reinforce the place for the removal screw in the printed pattern. Add the hole to the design and add a couple more shell layers to the print. Printed patterns are fine for one off castings where you don't care about the surface finish.

[@olfoundryman8418]

Jim, I am no 3d printing expert - complete novice in fact as I do not even have a printer! But following your suggestion the friend who does has confirmed the possibility of printing a small hole for somewhere to place the rapping bar, thank you for the idea. The problem with 3D prints is the layered structure, this grabs moulding sands - particularly fine ones like mine- the pattern is often too rough to withdraw from the sand without pretty much destroying the mould. That said I recently made a casting from a 3D print that was "as printed" (no smoothing no paint). It was a "bitcoin for Swdweeb (video shortly) so it has plenty of fine detail although not very much relief. My first try was not perfect but close very close. The print was done in ABS at minimum layer height. One of the problems with 3d prints is that for anything but thin reasonably flat work minimum layer height means very long prints and thus a much greater chance of print failure part way through which my friend tells me is all too common. I do look forward to 3D printing living up to the immense promise that it would seem to offer. The ability to print off a complicated pattern rather than having to whittle it out of a block of wood with a pocket knife is very seductive. In time I am sure the process will get there and I like the look of the newer light sensitive liquid resin type printers (if only one could afford the resin and if only they were a bit bigger in print size... Martin

[@jmhannnon]

I recently cast an aluminum hub for the sand muller I am building using an as printed pattern. The pattern came out of the sand ok but then I was not using very fine facing sand. I am still trying to find an easy way to smooth out the printed patterns.

[@olfoundryman8418]

Jim, Trying to find a way to smooth printed patterns - you and the rest of the world mate! I have tried the acetone trick with ABS prints - did not work for me but sometimes Abs is not Abs. Have tried spray on car putty - useless, PLA does not sand very well (reminds me of sanding rubber!) all in all its a problem and a great pity for the ability to draw up a job using say Fusion 360 print it out and use it as a pattern is very attractive but at the moment it impresses me as being a bit of a Holy Grail. My sand measures (with a micrometre - silly way to measure sand I know) 0.006 inch max so even with a print at 0.004" layer height and that could take many, many hours much of my sand will get under the "overhang" of each layer. The result on pattern pull out I am sure you can imagine. 3d printing though can only improve as time goes on and I doubt that it will be long before it becomes a very useful pattern making tool. I await that future with much eager anticipation... Martin

[@thomasreed325]

Great video! And as always very instructive, thanks again.

[@olfoundryman8418]

Thomas, If you fell that you have learnt something I am well pleased. Go forth and use the info with gusto!... martin

[@dfross87]

@18:35 I can't imagine why having a 3/4" (guess) thick steel plate attached to the bottom of the casting would make it heavier?!?

[@olfoundryman8418]

Df, Yep, it was pretty close to 3/4", Obviously it does not make the casting itself any heavier but it does make the assembly of mould and casting quite a bit heavier and that is what I have to handle if I can not get it off the plate easily. I have a few years and everything seems heavier than it did a few back ago!... Martin

[@tylerkrug7719]

What was the powder you put on top of the feeder? Really cool

[@olfoundryman8418]

tyler. It is an exothermic called "Ferrux NF" it is made by Foseco and its job is to generate a lot of heat this keeps the feeder liquid for longer so it is better able to provide feed metal to the casting underneath... Martin

[@seafurymike]

Great episode. really enjoyed watching it.

[@olfoundryman8418]

Sea, Glad that you liked it... martin

[@mrgreenswelding2853]

Thats just awesome! I wish i had a fly cutter like that, but i would give that wish up for milling machine. Lol!! What was the stuff yoou put on top of the casting after pouring?

[@WaltSorensen]

It's a sand (or possibly Exothermic reaction powder) added on top of the riser to slow heat loss from the riser, by slowing the heat loss it helps slow the solidification of the riser.

[@olfoundryman8418]

Mr Green, The fly cutter - a four carbide tip version is just a purchase of a cheapish tool supplier it is 63 mm diameter and is complete with a BT 30 taper to suite my mill. They're very useful for work like this and in skilled hands (unlike mine!) thay can produce very nice looking surfaces. The stuff I put on the top of the feeders is an exothermic compound. It is called "Ferrux NF' and it is made by "Foseco". It catches fire and thus generates a lot of heat and its ash is quite insulating so it heats the feeder up and then keeps it hot, so as Walt suggests the feeder is better able to provide the necessary feed metal to the casting below. I use this on most of my castings but for big work (well, big to me!) its use is just about mandatory. I guess its sort of like "thermite"... Martin

[@tylerkrug7719]

Did you make all those flasks or are they bought? Thanks

[@olfoundryman8418]

tyler, I made them. It took quite a while, very much a labour of love but they have been indispensable ever since. In an upcoming two videos (when get time to do them) I am going to do a review about my journey of 55 odd years through moulding boxes - what I tried what worked what didn't etc. The second video will show how to make a very versatile metal flask well suited to the needs of the hobbyist... Martin

[@jkay3161]

I do enjoy watching your videos

[@olfoundryman8418]

Jkay, People enjoying my videos makes them worth doing... Martin

[@jkay3161]

I’ve always wondered is this a hobby or a source of income for you or both

[@olfoundryman8418]

Jkay, A declining source of income. It kept the wolf and the bank from the door for at least the last 30 years. But now with declining customer numbers and age slowing me down its just a way of paying the health insurance 😁... Martin Ps. Its always been a hobby too.

[@swdweeb]

Hi Martin. I noticed that a pouring basin is conspicuously missing. Is because the sprue in this case mold is so tall?

[@WaltSorensen]

The yellow extension is a sodium silicate or ceramic pouring cup providing the larger target to pour the metal and to match height with the extended riser. I believe since it's pouring onto a chill there is less need to slow the speed of the metal with a combination pouring cup/basin so it will not erode the inside of the mold. I believe the sprue is sufficient to slow the metal with the chill. (There is probably something additional going on in the decision; such as most of the preformed pouring cups I've seen do not have a basin included) here is one example where you can order those preformed cups www.metschinc.com/pouring_cup.html

[@swdweeb]

Walt, what are you doing over here? Are you cheating on me? :-D You hit on the essence of the question, speed. I thought that in addition to providing a "hitable" pouring target that the basin also served to slow the fall of the metal. I'm still trying to get my head around all of the benefits of the tapered sprue. I should probably know this by now, but I didn't think the taper was there so much as a "slower" but rather to provide a less turbulent delivery to the part. So much to learn...

[@WaltSorensen]

Hey Perry, I'm just watching beautiful castings being done. (lol cheating... I'm so busted. Please don't let my other 111 other subscriptions know I've been watching other channels and random videos too lol) Yes, the pouring basin helps to additionally slow the metal as it's being poured besides being a target to hit while pouring (a target is especially needed with the small sprues). So with the sprue, it's best practice to always use a tapered sprue. reducing turbulence, and preventing gas entrapment are all reasons for a tapered sprue. porosity of a casting (air or other gases trapped inside the casting) is caused by aspiration of air and volatile compounds from the mold which occurs when the sprue is not tapered or a sprue several times too large for pouring speed such that the sprue can never fill during the majority of the pour The taper ensures that the volumetric flow rate of the metal is constant into the mold (once the sprue has filled). This is a condition the comes from the continuity equation and Bernoulli's equation. here is a reference that covers a lot of the details in general terms. (not the more technical side I'm usually on) www.rotblattsculpture.com/Articles/sandcastingproce.html

[@swdweeb]

Given that I cheat the same way, I guess I'll let it slide ;-) That's a great article, it says a lot of the things that Martin has been telling me over the last few months. There are one or two differences but it's pretty complementary. Thanks

[@WaltSorensen]

You are welcome.

[@steverowland1898]

Where do you buy your flasks?

[@olfoundryman8418]

Steve, I did not buy my flasks I made them. I have a 6 part series on making metal moulding boxes but sadly ill health has prevented me from completing this series. I still hope to complete the series one day but for now it ends just before the most important part - fitting the pins... Martin

[@steverowland1898]

@@olfoundryman8418 I subsequently found your other videos and binge watched many. Well done. I hope your health situation is not too serious! Your foundry knowledge is impressive. I find it interesting that your have not tried other sand formulations such as Petro or sodium silicate. I am just starting out and I am trying to learn all I can before committing to a plan of action for casting aluminum and brass. My wife has a pottery kiln which I plan to use instead of a blast furnace. Do you see any problems with this? No one else on KZbin seems to be using a kiln, perhaps it takes too long to come to temperature? After watching your videos on the evolution of your flasks, I think I will fabricate mine from rolled 2 inch x 1/2 x 1/8 steel channel with the leg inside the flask. They would be stack-able with steel pins in holes and slots as your recommend. Again, any thoughts? I saw your video on lancing to remove hydrogen, but I do not see this step in many of your videos. When is this necessary? Cheers.

[@olfoundryman8418]

@@steverowland1898 . Well, I do use sodium silicate sands for some cores. To be honest I do not like it that much - I prefer shell core if I can run to the necessary metal core box required for shell work. I find that the sodium silicate cores need very careful venting. At least that's required with my home brew for them. I have often thought of trying petrobond as it is very good for things like plaques. But at $4.00 per Kg it isn't cheap and I tend to work with 200 plus kg of sand. I could have tried maybe 50 Kg as an experiment but commitment to paying work slowed me down and then much of the petrobond available here in Australia is not as fine as it should be - in fact some of it is absolutely awful and I did not wish to pay for rubbish. If you want to see a particular skilled use of petrobond have a look at this bloke kzbin.info/www/bejne/Y5nPaGmGoJmUp8k I have seen people use pottery kiln type furnaces for metal melting - mrpete222 I think used something like this. I don't see anything really wrong with the idea but electric melting is usually a bit slow and any splashes of metal or flux on the heating elements will shorten their life. I see nothing wrong with the idea of steel section, but it will make for heavy flasks and the tend to be too damn heavy anyway. However if well-built they will last for life and provided you do the pins right - nice fitting slot and holes, smooth hardened pins etc - you will be well pleased with them - wooden boxes are the pits! 2 inch though seems a little low - most of my boxes are about 85 mm high - 2 inch (50 mm) does not give you a lot to work with. Some of my videos probably show a little of actual degassing. There is not much to see during the process so I don't tend to show much of it. Also I do not degas when doing gravity die work as the quicker solidification with this process usually prevents hydrogen porosity forming (or at least it keeps any hydrogen bubbles so small that the cannot be seen with the naked eye even on a well machined surface). With sand casting however the longer solidification times can lead to clearly visible hydrogen bubbles on a well machined heat treated surface. Un-heat-treated and therefore torn smeared machined surfaces usually hide even quite large hydrogen bubbles as witness many of the apparently porosity free machined castings one sees on YT made by less discerning practitioners. So with metal destined to be sand cast I always degas.... Martin

[@steverowland1898]

@@olfoundryman8418 Hi Martin, Thanks for the feedback. I will go for a propane furnace. The kiln is only 8 kW so heating time would likely be an issue. Also, my wife would not be pleased if I damaged her kiln. Best regards from Canada. Do you have a shell core video? Steve

[@olfoundryman8418]

@@steverowland1898 Ah a Canadian - Both my parents were Canadian Dad from Agassiz BC Mum from Winnipeg so Iam sort of almost Canadian myself. Greatings back from Melbourne Australia - the land where it seems only idiots vote! I think your choice of furnace is wise - got to keep the ladies happy 😊 I have several videos on cores :- Shell cores kzbin.info/www/bejne/Y3-umnacZ8Z2mck kzbin.info/www/bejne/on_bqKWJr9Jsp5o kzbin.info/www/bejne/pIKwY6aiq7WHh68 kzbin.info/www/bejne/jKuvoJiwo56Nga8 Silicate cores kzbin.info/www/bejne/jXndaqmkg7-rsNU kzbin.info/www/bejne/boXUdH5tpalnfLs Enjoy... Martin

[@1day129]

how do you remove porosity? did you use your argon lance. that casting is really good!

[@olfoundryman8418]

1day1, Yes I did use my argon lance although it has undergone some improvements since the video showing its construction (I should do an update video). But also the casting was made against a steel chill. The chill provides quick solidification and generally speaking the faster the solidification the less the porosity in and the finer the structure of the casting. Also the chill sets up a steep temperature gradient between it and the feeder - that too is a recipe for low porosity levels. Yes, this casting was good it looked like bar stock when I machined it. I was quite happy with the result... Martin

[@woodsman2433]

I am my own flasks out of timber but your professional ones are the bees. Are they your own work?. If so how did you make them I am just getting into casting and find your videos extremely educational keep up the good work Woodsman

[@olfoundryman8418]

Wood, Yep, flasks a real pain! I started with wood - everybody starts with wood! They are not all that good and they are short life and not as easy to make without a twist so that they will sit flat. Some years ago (about 40!) I decided that I needed a lot of boxes the same size and they needed to be better than wooden ones. I went through a few iterations before the design I now use in the main. The first ones took a long while to make as each side had to be individually cast in sand and then machined (usually but not always machined) Thus for 10 boxes I had to do 80 castings! For my last lot I made a crude die and gravity diecast 170 sides in a day or two. I am planning 2 videos - one on my 50 years journey through moulding flasks the good the bad and the indifferent, and a second one how to make a versatile (aluminium) flask with decent pins that is well suited to hobbyist or small production work. I will make one in the video and who knows I may just give it away at the end of the video (although if it turns out as well as I think it will I may keep it for myself 😊… Martin

[@woodsman2433]

Thank you so much Martin for your reply your videos are an inspiration to me, your work man-ship is second to non. Look forward very much to the video all the very best Woodsman

[@danharold3087]

I’m curious why the steel plate is heated then allowed to cool. Why not heat it to the desired temperature and use it right out of the oven.

[@WaltSorensen]

it's heated to remove moisture that may have been absorbed by the surface of the chill, that's mentioned in the video at 0:50 . but the steel plate's function is to be a "chill" and to do that it should be at room temperature which is why it's allowed to cool before casting. A chill is used to promote solidification in a specific portion of a casting. One common reason to use them is to promote finer grain in areas of the casting that need higher strength and ductility (among lots of other reasons to use chills). here is some reference material which will go into more information on the topic foundrygate.com/upload/artigos/CHILLS%282%29.pdf

[@olfoundryman8418]

Dan, As Walt suggests the plate is heated to remove moisture and any other volatiles that might be lurking around. I sand the plate first and some people sand blast theirs. But its a bit like skinning the cat ,there is more than one way of doing these things. Indeed, in a video in preparation now I do cast with the plate hot straight out of the oven or as was the case not an oven but a gas torch which played on the plate until just before the sand half of the mould was placed and then poured asap. This was a slightly different set of circumstances and you will see why when the video comes out. Note that if you do put a sand mould on a hot plate you have to pour quite soon. If you delay too much the heat of the plate will drive water out of the sand and thus create a 100% humidity atmosphere in the mould cavity, if, because of unnecessary delay, the plate now cools to below 100 deg C some of that humidity will condense out on the plate. This will create steam blows as the metal flash boils this condensate and thus ruins the casting. I never touch the plate surface after heating and I like to give it a light dusting of parting agent as a sort of film to aid air removal (a pet theory☺️) To be honest I am no expert with chills but am about experiment with cross hatch patterns on them (yet another video there) for ones that are moulded in to green sand and thus can not really be heated. Its a learning experience for me Walt is also right about the fine grain thing, it extends down to the micro level as it also produces fine microstructures. Strength and ductility (in particular) improve as does response to heat treatment, machinability is better and machined finish is improved. Then of course there are the benefits that come from shrinkage and gas porosity freedom that judicious use of chills can provide... Martin

[@TomChame]

Very interesting , thank you.

[@olfoundryman8418]

Tom, My pleasure... Martin

[@clarkeeasterling3225]

Great Job👍🏻

[@olfoundryman8418]

Clarke, Thanks you for your comment and nice to hear from you again, how goes it all?... Martin

[@WaltSorensen]

3D printing like casting has minimum thicknesses that you have to think about for the prints.Depending on the material the minimum wall thickness is between 1-2 mm. There is also an aditional thing with 3D printing called "fill or infill" which impacts both the speed and the strength of the print. The higher the fill percentage the longer the print will take, the more material is used, and the stronger the final part (up to the maximum for the material). Prints can be designed with some areas having really high fill percentages and other areas having lower fill percentages. Unfortunetly not all 3D printers can print with varying fill percentages (maybe someday they will all capable of more complex fill designations). rigid.ink/blogs/news/optimum-infill

[@olfoundryman8418]

Walt, Unfortunately the friends printer is one of those that can not print with varying fill... Martin

[@srDeltahunter]

nice job...

[@olfoundryman8418]

Hector, Thanks I appreciate your comment... Martin

[@AWAradiola]

This part wouldnt be for a bench top Hercus would it? Great vid, subscribed!

[@olfoundryman8418]

AWA. Yep, dead on, they fit a Hercus PC200 but will also fit just about any other small CNC lathe. The friend (smallcnclathes) has sold a few of them. We also cast tool holders for the PC200 carousel. Thanks for the sub I need all the ones I can get.😀 The friend and I are in Croydon are you close? Do you know Arron?

[@seanwatts8342]

Al U. Meeneum... I heard he's a nice guy.

[@olfoundryman8418]

Sean, Yes, but I also hear that he is just as nice and maybe even nicer than Al. U. Meenum 😏…. Martin

[@gaetan8401]

Awesome

[@olfoundryman8418]

Gaetan, Thanks for the comment.. Martin

[@EmmaRitson]

interesting stuff. ive always held that 3d prints make crap patterns. glad someone supports me. most people tell me im not doing it right. stick to wood i think. thanks for sharing.

[@markfryer9880]

I am more of the opinion that 3D printing is best used for pattern parts that would be to difficult, slow or dangerous to make out of wood. It also depends upon the skill sets of the person as to which direction they approach from, hands on will come from wood patterns, while a person well versed in CAD will probably come in from the 3D printing pathway.

[@olfoundryman8418]

Emmas, Mark, Yes. at its current stage of development 3D printing does seem to leave a bit to be desired as a good pattern making method. I have tried a quite complicated pattern an the finishing work was prohibitive would have been easier to out with the pocket knife and a block of wood. However in an upcoming video I make a Bit coin for Swdweeb its a 3d pattern without any finishing and it does not work too badly at all. So the process is I believe viable within limits. The future though I suspect holds great promise for this way of pattern production These days most commercial patterns are indeed made via the CAD route coupled to CNC mills/routers. The greatly skilled pattern maker chisel in hand at the bench whittling away is sadly (perhaps) a thing of the past... Martin

[@unclebobsbees4899]

Martin, if the part is made from ABS, you can get a better finish with an acetone fog. 1/2" of acetone in a 5 gallon bucket. Hang the part above the fluid surface for about 5-10 minutes. Check frequently and be extremely careful when removing. The surface will be very soft and will even 'cast' your finger print. Pun intended.

[@jonatan01i]

11:38

[@ronyerke9250]

👍

[@olfoundryman8418]

Ron, Thanks ☺️... Martin

[@paulmuff9883]

Hi what’s the stuff you’re putting on the risers after poring & what’s it for? Manny thanks

[@olfoundryman8418]

Paul, The reddish powder I on the feeders immediately after pouring is an exothermic compound. It is called "Ferrux NF" and it is made by Foseco. Its job is to catch fire and generate a lot of heat which helps to keep the feeders liquid for longer so they are better able to provide feed metal for the solidifying casting below....Martin

[@smallcnclathes]

👍

[@olfoundryman8418]

😀