I have just posted an article about creating a pewter drinking vessel to the Casting forum of the Lochac Network. For those of you who follow my Pewter casting, you can check it out by click on the picture.
It worked out great, and I look forward to making more.
Finally! it’ been a while since I posted a pewter project post, but I have now got a few projects on the go so there will be a number of them coming in the next month or two.
This weeks project has been a personal token for an SCA member to give to those they favour. It is a simple medallion with initials on one side, and a raised representation of a logo/device on the other side.
Usually my medallions are carved into one side of the mould for depth and then the other side is smoothed and has the detail carved into that. For this particular token I wanted to attempt a fully symmetrical moulding process by carving half the depth into each side of the mould. I did this for two reasons, firstly, the one sided method I used previously whilst it makes for a nicer edge, usually needs alot more work to clean up. Secondly it allowed me practice in aligning the two halves of the mould, whilst the old method allowed for misalignment, it meant that the main image was not centred on the finished token, and it would look kind of wrong.
After some experimentation in attempting to get a good quality pour each time (see last post), I managed to find the best combination of temperature and mould tapping that resulted in a great amount of detail showing. This further experimentation also made me realise the importance of the mould tapping and the continuation of it until the entire button* has solidified. It seems that during the freezing process pewter can sill move past other parts that have frozen solid. I suspect this would be similar to the crystals of ice that form in water, they allow water to pass around them, but still hold their shape.
Interestingly this also brings to my attention the creation of another type of artefact on an improperly cast item. This artefact is caused if the mould moves during this crystallising phase of the freeze, and creates a texture like the one in the picture to the left. It is rather a fine texture, however given the choice of all three of the artefacts described here and in the last post, I would rather this one, as the detail of the casting is almost perfect. To reduce or even eliminate this artefact I would suggest the use of either wiring the mould together tightly, or using mechanical clamps to stop the mould from moving during the tapping and pouring process. I may even attempt to make some sort of mechanical tapping/shaking jig so as to reduce stresses on the soapstone mould as well as the chances of the mould moving.
In a happy coincidence when I was checking the email to confirm that I had gotten the commission done as requested, I noticed that I was missing a vital part of the Dragons. So the above information about the tapping/shaking process was only discovered after the wings were added, and the entire batch recast. I’m sure my customer will be much happier with the better detailed casts than he might have been with the previous batch, specially as his Dragons are now actually dragons and not Lizards. ;)
It’s about time I got back to some real Pewter casting and the reporting of, so here’s my latest. I have recently been working on a token commission and actually paid attention to the detail of the results of the castings this time, so I thought I would write about it in an effort to further muddle it through in my mind as well as help the one or two of you out there.
When casting there are two main problems that cause artefacts on the cast item. The first is air pockets, and the second is pewter shrinkage due to the freezing process. Unfortunately in period soapstone casting, the solution to one of these problems is also what causes the other, and a balancing act needs to take place to minimise both effects.
Air pockets can be caused by two reasons that I have been able to work out, though I believe the second is another issue which can be fixed separately*. The first is a lack of air escaping the mould before the molten pewter freezes, either by air flow dynamics causing restrictions in air flow out of the mould as the molten pewter enters, or the pewter freezing before it gets a chance to fill all of the detail. This can be minimised by using a hot mould that allows the pewter to run into all detailed parts of the mould before it freezes, you may need to still play with the air flow dynamics on some moulds to ensure that the pressure of the liquid pewter entering the mould isn’t causing an air pocket in the mould to be trapped.
The secondary artefacts created when the molten pewter freezes and shrinks is a little harder to control, as the easiest way to control that is to have a cold mold and a quick pour of the molten pewter into the mould. The cold mold freezes a skin of pewter allowing the detail to remain. Freezing the pewter from the outside just a touch faster than it would with a hot mould this allow a harder skin to retain the detail whilst the pewter freezes and shrinks. Another way to stop the shrinking from effecting your finished casting is to have a large enough sprue connecting the pouring button with the cast product so that there is enough room for the shrinking pewter to pull down more molten pewter from the button, however this is not always easily possible, as this sprue needs to large enough to allow the sides to freeze before the centre.
Another method of minimising the effect of shrinking on the casting is to rapidly tap the mould on a wooden surface as you are pouring the pewter. This has the effect of increasing the pressure in the mould and effectively hammering the molten pewter into the details. It needs to be done as you are pouring, and you need to be very careful as you don’t want to move the mould parts, or splatter molten pewter.
These details leave me with the conclusion that in order to get a perfect casting each time from a gravity fed, non-pressurised soapstone mould casting there needs to be a very delicate balance between the temperature of the soapstone mould and the temperature of the molten pewter. If I were more serious about this process I would attempt to investigate this further with more period techniques for estimating the temperature of both mould and metal, however I believe that knowing that the balance exists and some means of minimising it’s effects are enough for me to continue. The art of getting a perfect casting from each pour is one that whilst very rewarding, is not necessary with the ease of turning out pewter castings it is often better to do the best you can, and recast the ones that don’t work. Of course, if it’s the techniques that are causing the artefacts in the first place, then these techniques do need to be addressed.
Well, it seems that today I sold my first Pewter badge on Ebay. That would be great if it hadn’t taken about 2 years at roughly $15/month to do it. ;) Stupidly this is totally my fault for not actually doing anything with the Ebay store, just leaving it there each month paying the fee. I guess what I should do is actually use the Camera I bought specifically to increase the stock in my ebay store to take photo’s of other things, and add them to the store. This I should do now that I have some time… In fact this I should have been doing since I was made unemployed as that was the only pathetic excuse I had back then. Feel free to hassle me into getting stuff on the Ebay store!
So what have I been doing in my unemployment instead of doing sensible things like selling stuff on Ebay? I have been getting armour and stuff ready very slowly in an attempt to start fighting heavy. It’s another one of those things that I have been procrastinating about for ages, so I have been doing bits here and there to get prepared for it. Today I spend an hour or two modifying the faceplate of my helm so that I can get the legal 1″ apart bars welded in place. I have also needed to change the way the helm and faceplate meet, so it shall signifficantly change the look of the helm. Last week I made a Boss for my shield, and once I manage to find my acrylics I shall paint the shield and finish off the edging.
Like always I think there is always a better way to do something and I experiment with everything. When my helm was originally made I used boot polish to prevent it from rusting as I’m not a fan of the shiny helm look or the look of painted metal but I do enjoy the look of bear rough metal. This provided a happy compromise, giving the metal a dull grey, but still metallic look. It has lasted really well only showing sings of rust where friction had rubbed the polish down to metal from the canvas in my armour bag.. My latest experiment is to make a shield edge that lasts longer than the normal shield edges I have seen… Now I must admit to start with that my experience of shield edges is very limited, so I won’t confess to knowing whether this has been tried before or not. The shield edges I have seen are either aluminimum channel then hosepipe then tape, or just the channeling with leather edging over the top. What I’m going to try is to silicon on a rope around the outside of the aluminimum edging. I’m hoping that this will provide enough of a buffer between the blow on the edge and the wood to stop the wood from starting to split. It should also increase the life of the leather going around the edge as the leather will no lnger be hitting directly onto metal. Anyway.. that’s the theory. ;) Time will tell, and there’s also the fact that being a newbie fighter, my head is likely to be taking most of the blows, not the shield edge.
That it from me tonight, but remember feel free to hasle me about either looking for work, or getting the Ebay store working better.
I have been tinlkering of late with constructing pewter drinking wares, as I have been wanting to experiment in that area for a long time and just never got around to it.
My housemate has been attempting to convince me to mould a cup in a single piece, however I have been tinkering with constructing one from sheet. This meant making sheet pewter, as it’s rather dificult to get pewter in sheet form. Those of you who read my site regularly will remember the post earlier in the week where I discussed wooden moulds, and making a mould from two pieces of flat pine.
The pewter I cast from that mould has since been beaten into a truncated cone, and had the seam welded to form a nice cup shape without a bottom. If all goes well during the coming working week, I shall fit a bottom to this and then clean and polish the raw cup before attempting some decorating on it.
Still can’t forget those Radburne War tokens as well…
Yikes! It’s time I started concentrating on the Radburn war tokens, as I promised that I would once again supply the tokens this year. The general consensus is for a Tower, and being an archer I am quite keen on shooting from towers, so I think a tower it shall be. I am conflicted about how to make a tower better than the gate that I made for them last year, but I am keen to continue the fort motif from last year.
The other alternative is a Radburn shied, which I have in mind so that it matches the sword from the first year. I may keep that one for next year though, I guess we’ll see how I go with the Tower first. So I now need to contact the Steward and find out how many are booked so I know how many tokens to make.
I have been experimenting more with short term wooden moulds for pewter work these days and I suspect that it was used in period for pewter work more than has been documented. The pine store-bought wood I have been using holds up remarkably well to multiple castings and even when it does seem to burn, it seems to retain it’s integrity reasonably well. Using the wood allows larger filigree type works to be created reasonably quickly with a sharp carving tool and some skill. the wood seems to allow a remarkable amount if details and because of it’s insulating and porous qualities seems to be a great medium for making larger flatter pieces as the molten pewter flows to all extremities of the mould before freezing.
Earlier on in the week I used a wooden mould to create a piece of flat sheet that I could turn into a cup by rolling and then soldering the seem and the base in place. I suspect with a little more care in creating the mould I could make this sheet a lot thinner and much smoother. Though the other consideration for making flat sheet is to use sheet metal, and make a 3 piece sandwich with a sheet metal blank sandwiched between 2 pine boards.
I know I should change my chosen metal from Pewter to silver as more and more of the things that I want to make are much better when made in silver, and I could also cast the silver in the soapstone moulds I already have. However it seems that my skills are more and more being used to make event tokens which is far more rewarding, as tokens seem to get kept, and they have a larger audience rather than special silver thing’s that are only special to those they were made for. Anyway, I haven’t done much these days, so I shouldn’t worry too much until I get to a point of needing to evaluate.
Lately life has been getting in the way of all the fun things I have been wanting to do and having been promissing other that I would do. Such things as Trinkets for valuable allies or tokens for trade, not to mention my desire to write rubbish in here every now and then. Ahhh Such is life, and as such this post like others before it will be just a general one.
Pewtery goodness is still happening, and lately whilst I have not had as much time as I would like I have created a nice Double Sided token for a friend and used s0ome techniques I have used before but not really described to increase the detail whilst also decreasing the time they took to clean up. These tokens had a small ring on top of them to allow a string or small chain through, as the raw version of this was rather rough I used a pair of pliers to press the rough shape into a round shape and allow the teeth of the pliers to bite in leaving a nice knurled finish. (Stay tuned for Photo’s next week.)
Last weekend I went for a drive which turned out a little longer than I thought because of my bad planning and lack of fore-thought. I headed down to Ballarat to join the members of Stormhold, Arrowsreach and Cairnfel in their annual Survey expedition. Walking into the event I was amazed but nut surprized at the authentic feel and beauty of the site. With a small pine forrest seperating alot of the mundanities from the campsite, there was both lots of natural shade and a feel that we were away from everything. The food was good and the company great, I meet some old friends and made some new ones, all in all a fantastic weekend. I really enjoyed the event and wish to thank the hosts and organisers Ava, Hrothgar, Eleanor, Hanbal and all the others that helped. Well done indeed.
And now I must get back to my latest project, one which I much keep quiet until after Canterbury Fair (which I won’t be attending, but which I have been working hard to get stuff ready for. Til next time, take a huge bite out of life, before life gets a chance to take a huge bite out of you. ;)
P.S. Oh, BTW, the recent change in theme is because I updated the Wordpress software on my site and decided it was also time for a change of look… Hope you all like it, allong with my fun little plugin hack… I may even attempt more of those plugin hacks to intergrate this site more with Facebook.
Well, actually the Nuttyness is me staying up until 1am casting tokens for College War… Tokens that I’m kinda not really into making, even though I promised I would. The good thing is that part of the deal was that I would supply them straight from the mould, with no cleaning up of the flashing. What are these tokens? Hmm You’ll have to wait and see… Tis a surprise for the College War attendee’s.
Though I will stick up photo’s on my Flickr on say.. maybe.. possibly… around… in a round about way… say… Tuesday. ;)
Ahhh… It’s so good to be able to spend a weekend doing not much. After the last 3 weeks where I was in Sydney for 2 weekends, with all the driving and the visiting and the well… missing out on doing… ummm…. nothing…
So this weekend I had a lazy Friday night (I was meant to go to the Pirate night at the Uni, but well… A better offer presented itself, and I spend a lazy night chatting and watching umm… something on DVD. Saturday was slightly more energetic with 2 hours volunteering at the Archery Club moving paver’s, can’t wait to see how it comes out. In the afternoon I hung out washing, and sorted some stuff to make more than just a walk way through my bedroom.
Sunday I spent doing not much… followed by a little more washing, some sorting through stuff, and then moving a trailer and hacking off some bits of it so that a new towing frame can be constructed for it. All in all it was a very lazy weekend… though I am looking forward to the town archer weekend next weekend. I might even turn up to Pot Luck feast, if I can be arsed to get some food together for it.
As for this coming week, I need to finish off the soapstone mould for the College War Tokens, and then cast 50-60 of them when the pewter arrives. The mould I started whilst teaching a pewter casting class in Rowany is surprisingly OK by my standards, so I just need to add a little more detail, and cast a large batch in the next week or ten days. Whilst it’s a little flimsy for my liking, it still does work as intended so should be fine to be used as a small token for college war.
With my recent experimentation I have been thinking about how to keep the process still period whilst taking advantage of the new moulding technology. I might start considering doing things initially in a soapstone mould, and then moving over to an RTV mould for larger production runs where problems exist in the pouring of quantity. This would mean that the art form is still maintained whilst the ease of production makes large quantities easier. and RTV mould could be made so that I could cast 5 or 10 of an item at once.
On a different note, I would still like to attempt the pressure casting technique that I was told about one evening over some wine at a friends place where steam is used on the button whilst it’s still molten to create a small steam explosion and push the pewter further into the mould. More on this in the future.
I tried out two types of new moulding techniques last night.
The first was using a plaster like mix to create cheap blank moulds for carving, as an alternative to soapstone. The plaster needs some more experimentation, it seems to not heat up like the soapstone, and whilst being more insulative for larger pools of molten metal, it takes the heat out fast enough to stop the flow. This I shall continue to experiment with, as I want to develop a small paired blank mould that I can mass produce easily and use for teaching.
The second was the RTV Silicon moulds I was playing with in my last post. The RTV mould stuff is fantastic, and I’m annoyed that I didn’t actually try it sooner, like about a year ago when I discovered the stuff. I need to get myself some small to medium sized kitchen scales so that I can more accurately measure the ratio of compound to catalyst, and I need to remember to mix it more thoroughly, but the detail that can be achieved with this stuff is fantastic. :) Unfortunately my cutting out skills aren’t as good as my carving skills, and I ended up making an error that later cased the failure of the mould. Just a small failure, but one that noticeably modifies the end product. The first casting from the mould was reasonably detailed, but the third started to get more detailed as the mould started to warm up. This is great stuff, and when I can work out a better method of making the moulds I shall start making saleable items this way.
I got made redundant when I got back from Festival, so things have been a little slow with me working out what to do next. Luckily the redundancy allowed me to clear a portion of my debt, which freed up some financial stress. ;) This in turn allowed me to splurge a little on some things I have been meaning to try, such as RTV Silicon moulds.
RTV Silicon moulds are a liquid Silicon that hardens at room temperature and is suitable for moulding pewter directly into. This allows me to experiment with an almost lost wax technique without having to re do the lost wax mould each time. Basically I end up with a reasonably flexible mould that allows all the detail of the lost wax process, with the re-usability of the hard carved mould technique..
Currently I’m just experimenting with it to see how useful it can be, but if all goes well, it might be able to produce some really great stuff.
As usual with anything I do… I’m kinda learning by experimentation, as opposed to actually being taught, so stand by for some notes and stuff in the next few weeks.
What follows is just some thoughts and theories only, based on my own pewter work, and understanding of production and manufacturing techniques. It is by no means researched and even my own experience does not compare to technology that would have been available.
I have of late been making largish batches of tokens, particularly for Rowany Newcomers, and this has given me pause to think of production techniques that might have been employed to allow production of a large number of tokens rather quickly.
Given the numbers of finds of tokens and souvenirs through Europe, I personally believe that there would not have been someone who specifically just made these tokens. If there was, they would have most likely only done it as a part time thing, specifically for a coming event. They might be a jeweller, though the skills required such as a steady hand, artistic flare and patience mean that it really could have been anyone, much like it is in the SCA.
The quality of the carved moulds varies greatly which seems to indicate to me that some might have been jewellers who are skilled in carving, whilst other moulds are rather rudimentry and might have been made by some other person with suitable carving skill.
There are indications that numerous moulds of the same pieces were made, though there isn’t much evidence as to whether this was to replace moulds that broke, or wore out, or was to speed up production. My guess is they were made to speed up production, as most souvenirs would have had a limited window of opportunity such as an event or such.
In my practical experience I’m guessing that production was either done in stages, with quality control between stages. With child labour not being an issue, I’m guessing that the work would have been broken up between various workers, one pouring the molten metal, one collecting those castings and checking whether they were acceptable, then possibly clipping off the excess, and possibly even one worker finishing off by cleaning up the piece to a sale-able item. The use of a second and even third worker here makes the process one that can continue at a reasonable rate.
In pouring the casting I believe that there would have been no waiting for the button to cool, the caster would have poured in molten metal, waited a second or two, then poured back out the molten button before it completely set. Through experience when casting tokens and small flat items the first second or two is enough to have the actual item needed set within the mould, and the button is just excess metal that would be better suited back in the pot to continue the casting process. It’s also quicker to pour this back into the pot whilst it’s still molten rather that let the button cool, cut it off then have to re-melt it. This would be a key to producing large numbers of castings, and having a second person to do quality control means that the person pouring the castings can just keep churning them out, whilst the other person is sorting and throwing bad castings straight back into the pot whilst they are still hot.
Here ends my theories and suppositions… If you have opinions please feel free to comment.
Arrrrgggghhhhh!!!!
After 10 castings, the mould for the Newcomers tokens that I have been working on for the last could of weeks split… right through the middle of the actual detailed part. This is a real annoying as there isn’t really enough time to carve a new mould.
There might be a chance that I can still use silicon to glue the mould together and continue casting… So off to the hardware store tomorrow to see if I can recover the mould.
Its been a while since i posted about pewter… actually its been a while since i posted about anything substantial.
Anyway, just thought that I would let you all know that my pewter work is still proceeding along. I shall shortly be doing some stuff for newcomers, both for the A&S comp and for the event its self.
Im also still concidering the idea of running a day long pewter workshop. Teaching the basics, as well as allowing time for everyone to create something great. I’ll keep you all posted if this turns into more of a plan.
I was casting tonight… And because I was a little too careless with getting to close to the size on the mould I was using, I managed to blow out the side trying to remove a casting… This wasn’t good, I had 5 castings to go for a commission job, and I wanted to deliver the job tomorrow night at Fighter Practice.
Duct Tape to the Rescue!
Just goes to prove that duct tape can not only hold people to floors and ceilings, keep panels and lights securely fastened to trashed cars, seal broken windows, and work wonders with SCA Armour… Duct Tape can also be used in the Arts and Sciences of the SCA to hold crucial pieces in place allowing a job to be done. Yay for Duct Tape in the SCA!
OK.. So today I was bored and looking for something other than stuff I had to do to play with, so I dug out the partially completed mould I started for my challenge of making a fully cast pewter chain. The mould makes 2 links linked together, with a place to then put those pieces so that the next ones can be cast in place. This mould was fairly ambitious and only really survived one casting, as removing the pieces from the second casting showed that the mould had broken and allowed molten pewter to encompass the previously cast links.
Whilst this attempt was more of an experiment to see if it could be done, I am very tempted to try a slightly different way of doing it so that the mold might last longer and therefore be capable of producing a decent length chain, as well as be able to link the chain back onto itself, which isn’t possible with the current mould.
The Technique uses period technologies in a soapstone mould to create Large linked chains… But it can also be used to possibly create linked tokens, badges or other periodesque pewter items. The produce might be documentable in the sense that the techniques and technology used to create them are period and documentable, however the produced items and the linking in a single casting are not. As always… I’m open to suggestion or discussion on this topic. :)
Today I found myself making a belt mount for someone and wanted to include integral rivets into the back of it. Because of the semi random nature of the rivet locations, it wasn’t feasible to create a multi part mould so that the rivets could be made and the casting removed easily. So instead tapered hole were drilled into a flat soapstone mould. These holes had the distinct problem of trapping air which stopped molten pewter from actually getting deep into them. To rectify this issue, the holes were drilled all the way through the soapstone, providing an easy path for the air to escape…. Though this also allowed the pewter to escape the same way. So what was the solution to this issue? How can you drill holes all the way through soapstone, and also stop the pewter from escaping whilst allowing the air through?
Bamboo skewers. Yes, bamboo skewers were used to make small little plugs that also allowed air through them. With careful trimming the skewers can be used to provide the correct length rivet too, by altering the length of the skewer filling the hole, you can adjust the length of the rivet on the finished casting. It works well, and is a method I shall be using for future belt mount with integral rivets.
It’s been a long time between posts… A lot has happened in that time that I wasn’t very open to discussing. Some of it life stuff, some of it Pewtery goodness. The life stuff just isn’t worth discussing, however the pewtery goodness is.
Baronial Officers Badges
I was commissioned to create some hanging badges for the officers of Rowany (Yay, I get one!!). The badges consist of two parts, with a small round link between them. the badge consists of a Rowan tree, with a frame around it, though the tree sits out of the frame slightly, making the frame just there for symmetry. These were cast so the back of them has a spot to mount a pin which is crimped in between two pewter lugs, with the third stopping the pin from sliding out. This method of holding a pin was stolen from Anzac badges I have seen in the past, and seemed to work quite well.
A side project stemming from this has been an attempt to get the Barony to allow me to sell the Rowan tree separately as a badge. The idea being that I remove the roped frame from the tree, attach a pin and sell these as a separate pin. These would be sold for around $5 each At any event I am at… however I have yet to get approval for that, so we shall see what happens with that idea. There is talk about the Barony using them as such as a populace type livery badge.
Indexed Moulds
I finally tried it!!! Yes, Sveinn has gone from using the basic two slabs of soapstone hand held together in roughly the right place, to using a 3 part mould with a total of 6 indexing nodules. Using the method described to me by Master Crispen, I have created a 3 part indexed mould. Now, I must confess, I cheated here… and used modern tools… After drilling the first hole by hand, I opted to use a Dremel tool to drill the holes for the other 5.
After casting using this mould… I have no idea why I hadn’t tried this method of mould preparation sooner… It’s amazingly easy to do, though it does increase the time taken to prep a mould. For flat one sided stuff, it’s really not worth the time, however if you are reliant on getting two halves of a mould to match spot on each time, it’s well and truly worth putting in the time.
My only issue with making moulds this way, is that I can’t preheat my moulds the way I used to with indexed moulds. Previously I used to plonk the soapstone in the direct flame whilst waiting for the batch of pewter to melt, however with an indexed mould, this would ruin the indexing.
Flying Monkeys
A week or two ago, Stanzi in St Florians put out a call on the Lochac list for willing participants in an A&S club type thing to get projects for Bethan and Berenger’s coming reign as the Crown of Lochac ready. I’m not sure if I can spill what I will be working on, or even show you pics, however just thought I would let you know to look out for pewtery bits on their royal highnesses during their coming reign.
An Interesting and slightly evil challenge
This evening whilst thinking in the manner that sometimes works well… I set myself an interesting task… One that requires some interesting puzzle manipulation, and careful planning. I think it can be done… and I think I know how I can do it… I’m hoping I’m right. Want to know the challenge? I challenged myself to create a soapstone mould in which I can pour a cast linked chain. Each link in the chain is cast already linked to the previous one.
What got me thinking about this project was the Knights chains, those big chunky chains that in some cases are nicely forged, and in others they are just decorative chain bought at hardware store. Thinking about them, I was trying to remember if I had ever actually seen one that stood out amongst them all… and whilst there are some very different ones, I couldn’t remember any very special ones… then I thought about a chain with detail on big chunky links, and how cool would it be to make one that didn’t have a single join on any link… So that’s my challenge to myself… And hopefully I think I can get it done.
Feel free to take up the challenge if you are game. ;)
Anyway, That’s it from me for the very pewtery post. Oh, other than to let those of you who care know that I am mobile again!! Have van… Won’t travel far, cause I have to work out how to pay for the repair….
Mmmm sleep…
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