Wooden master and stunt casts

[steven giunta]

Was searching through photos and came across these.its the wooden master they used to cast the v2-3 and a cast of the v2-3 in aluminum. What I found interesting was the whole on the windvane. Was it drilled after it was casted or was it just a air bubble in the casting?also unfree the emitter Were it is attached to the neck there is a lot of left over metal there. The v3 also has this but I always thought it was paint that was put on to heavy and settled there. Guess I was wrong.

 

[LOM]

I came across these pics recently too.. There's some weird things going on but I'm glad to have found clearer pictures of these.

Here's some links to the propstore auctions for some higher rez versions for reference:
Metal Cast
Wooden Buck

I think that hole on the windvane is actually a bubble, even though it looks awfully similar to a starting point for drilling. It seems too high, when compared to the V3. When it comes to the metal under the emitter, I had also thought it was paint or even tape build up for awhile on the V3. However, in the V3 theory thread, someone who owns a production made casting said it was a part of their saber too, an artifact of the casting process, so that is the current consensus.

One thing that I find odd is how it looks like the neck to emitter plate looks like a separate piece:

This thread popped up at a really funny time - I recently talked to a wood turner about this, and he commented on how the emitter plate (looking at the cast) looks like it would have likely chipped during turning - and that's how it looks on the buck. Perhaps it broke and needed a replacement?

 

[Mouse Vader]

It might be worth noting that the wood master here almost certainly wasn't use for greensand casting aluminium. It's solid. To make a greensand mould it has to be two pieces, split lengthwise. This gives the seam line seen in the final cast piece (see Poopapaplaps thread). If this was used to cast anything it would be the resin props. A 2 part silicone mould can be made from a solid master by using plastacine & card etc to isolate half the master.

The hole is a bubble. In casting parlance a blowhole.

One thing that I find odd is how it looks like the neck to emitter plate looks like a separate piece:

Looks like that to me too.

 

[steven giunta]

It might be worth noting that the wood master here almost certainly wasn't use for greensand casting aluminium. It's solid. To make a greensand mould it has to be two pieces, split lengthwise. This gives the seam line seen in the final cast piece (see Poopapaplaps thread). If this was used to cast anything it would be the resin props. A 2 part silicone mould can be made from a solid master by using plastacine & card etc to isolate half the master.

The hole is a bubble. In casting parlance a blowhole.

Looks like that to me too.

I don’t know much about casting in aluminum.the only experience I have is watching a bunch of how to videos on you tube. But from what I’ve seen they are able to cast a solid piece with a two part mold made of sand and a box.they wouldn’t need to cut a resin saber in half.they could have just made a two piece mold. Like anything else you want to do a two piece mold for,you do one half,pour a mold release on the part that’s gonna touch the second half of the mold,I think powder is used for sand.then make the second half of tge mold. Separate them and you got a two piece mold. I’d imagine it being more trouble then it’s worth,making a mold then a cast,then cut it in half,then mold again.it Probly would have been easier to lathe copies then go through all that. They didn’t have to be perfect.
Also you can see faint lines through the wooden buck that are on the aluminum cast. If it was a cast of a cast ,those lines would be really hard to see

 

[Mouse Vader]

I think you miss understood me. I have cast brass with greensand for my work. Cast aluminuim is the same process (with the V2-3). I've just been researching casting resin. They are not the same method. Very basically: To cast metal you have to have a 2 piece master pattern (buck). You place one 1/2 on a flat surface (hence the split master to get a flat side) place 1st half of the mould box around it. Apply release agent (talc or graphite) ram in the damp greensand (your powder?) then turn the mould box, sand & pattern over. Then fit the other half of the master pattern (gen. has pegs to index) then fit the other half of the mould box, release agent & ram in more greensand to complete. The mould is then split open (very carefully) the pattern removed (even more carefully). Pouring gates can put in by hand or put in with the pattern. The mould reassembled & held together (weights or latches on the box) & the metal poured. Once cooled the sand is knocked out to release the casting. Flashing & gates are cut off (called fettling). Usually bits of the sand mould crumble of at the edge of the cavity when you remove the pattern, which you can see on the casting. You can cast from an unsplit pattern but only when this has just one side detailed & one side flat. PoopaPapaPalps has a whole thread reproducing this process for the V3-2.

Lineage Foundry Cast ANH Kenobi Stunt Hilts

EDIT 08/15/2018: Considering I've gone quite deep into the rabbit hole since posting this thread, and learning quite a lot along the way, I'd thought I'd update this but keep the original posts for posterity sake. EDIT 05/15/2020: Go to Post #111 for the latest, and currently best version...

www.therpf.com

As I said you can cast resin from a silicon mould made around a solid pattern. Here you 'mask out' one side of the pattern with Plasticine or card with a hole cut out fit half way round it & Plasticine to plug any gaps. Make card mould support round that, pore the silicone remove the masking make another card support for the other half. Pour that, then remove the pattern, cast the resin. Because you pour the mould you don't have to have the base support needed in greensand casting necessary to ram/compat the mould material.
If you only make a thin silicone mould you sometimes even make a single piece mould cast around your solid pattern. This would be flexible enough just to pull off the pattern/cast object.

Both methods here work with patterns made from anything. The pattern for the cast ally sabre is clearly wood, as you say. I think you must have misinterpted my post. I didn't mean they cast a resin saber cut it in half then used that for the ally one. I am saying that that wooden pattern had nothing to do with the cast alluminium sabres. If it was used in casting then it was for casting some of the resin sabres used in the film.

Making a split wooden pattern for the V2-3 would have started from 2 pieces of wood (1/2 thickness) pegged together then turned , then split. If you cut a turned one in half the material you loose in sawing gives you an 'oval' when cast.

Hope that makes things clearer.

 

[thd9791]

Never noticed the emitter was broken and reattached..

Mouse - in your opinion, where would you place this wooden piece in the timeline? It seems the misaligned grips were copied to the aluminum casts somehow

(given that this wooden one couldn't have been used to make the aluminum casts

 

[Mouse Vader]

Sorry thd. I don't know enough about these timelines. I would hazard a guess that this wooden pattern was made at the same time as the one they did use for the ally casts & by the same person? Use of a template for positioning the grips. That might be as simple as a strip of card with pencil marks to position marks on the work piece. All can say for sure is that one piece master patterns are not used in greensand casting for things this shape & the ally sabres are definitely greensand cast.

Emitter could have been made separately deliberately. No way tell which from these pics.

 

[steven giunta]

i Don’t think I understand why they couldn’t make a mold of that wooden saber. I’ve seen videos were they mold knives and round objects without having a flat side. I found a video we’re a guy makes the swords that Electra uses in daredevil. Why couldn’t you make the lightsaber mold the same way. That aluminum saber has the same tool marks on the bottom section as the wooden saber.https://m.youtube.com/watch?v=rsZMwbvYkIA

 

[steven giunta]

 

[chazzychaz]

It might be worth noting that the wood master here almost certainly wasn't use for greensand casting aluminium. It's solid. To make a greensand mould it has to be two pieces, split lengthwise. This gives the seam line seen in the final cast piece (see Poopapaplaps thread). If this was used to cast anything it would be the resin props. A 2 part silicone mould can be made from a solid master by using plastacine & card etc to isolate half the master.

The hole is a bubble. In casting parlance a blowhole.

Looks like that to me too.

I know there is more than one way to case metal parts, but In my experience any shape can be cast from a single solid shape. I did sand casting in high school, and I worked for a government contractor after high school pouring bronze in to sand molds. from time to time I worked on the Aluminum line. all bucks were solid one piece jobs. now considering the time and expense (in labor) it makes more sense to do the one piece buck. the seem line is a result of the two halves of the sand mold. I have talked this with my dad who worked for chrylser making engine castings and he said from a practical stand point the production of multipule dirty casts always come from a mold derived from a one piece buck.

 

[PoopaPapaPalps]

It might be worth noting that the wood master here almost certainly wasn't use for greensand casting aluminium. It's solid. To make a greensand mould it has to be two pieces, split lengthwise. This gives the seam line seen in the final cast piece (see Poopapaplaps thread). If this was used to cast anything it would be the resin props. A 2 part silicone mould can be made from a solid master by using plastacine & card etc to isolate half the master.

The hole is a bubble. In casting parlance a blowhole.

Looks like that to me too.

This is the original buck but it looks to have been refurbished and the two halves put back together. It also looks like the emitter, windvane neck up, looks to have been reattached or was a seperate piece. I can't explain that detail, but I can tell a seam when I see one. You can see the seam joining the halves on the pommel bottom and on the pommel itself, and faintly of the split line running along the clamp/body area. We have that old Archives photo showing it laying flat and as a half-piece.

It looks like I have to readjust my model again, because I have it matching the dimensions from the old books stating that the V3 was 6x5x29 cm. It makes for a very oblong thing.

 

[PoopaPapaPalps]

...

Making a split wooden pattern for the V2-3 would have started from 2 pieces of wood (1/2 thickness) pegged together then turned , then split. If you cut a turned one in half the material you loose in sawing gives you an 'oval' when cast.

I think this is exactly what happened with the original. I took pain-staking measurements from the old photo and my results when it came to casting produced extremely oval pieces, and fresh off the lathe, it would be an impossibility to create a shape like that. I think you can only get a glimpse of this on the V3 in this photo when it was on display:

 

[LOM]

Glad we can all agree the emitter looks like it was reattached at some point, I thought I might have been seeing things. I've also just assumed a two part red/green sand was used, and one half was 'bumped' before the pour leading to the seam line on the V3, so this is quite an interesting development for me lol.

I'm still pretty convinced the wood buck was the one used to create the metal castings, whether it was cut in half or not, because there's some small details where the booster meets the clamp section that seems to be present on the buck, the metal cast, and the V3 (based on the resin cast. Though, I admit it may just gunk from casting). As well as the wonky rings - seems like it would be too much effort to machine another one only to have it just as wonky.

I can't explain that detail, but I can tell a seam when I see one. You can see the seam joining the halves on the pommel bottom and on the pommel itself.

I haven't thought about it like that before - now that you mention it I do see a few lines that might be a seam. Are you seeing this? Or is it in a different spot?

We have that old Archives photo showing it laying flat and as a half-piece.

Also this is big news to me... Any idea where I can find this photo!?

 

[PoopaPapaPalps]

I don't know if this was from the original owner or from the "archives" but it's often referred to as the "eBay" photo.

I'm also fairly certain that the "bootster" was machined (if lightly) for the V3 as well. Most definitely the clamp/body section if it were to fit a clamp. This is most definitely the one pictured here, only fit back together and the seam filled.

 

[thd9791]

I always thought we were seeing the curvature of the other side underneath the windvane and emitter, that's a weird optical illusion if that's just a half sitting on a table. Wouldn't that mean the wooden one would have to have like 1/16 of filler all along the length (or however wide the sawblade was that sliced it)

 

[PoopaPapaPalps]

I always thought it was half but it could very well be. I honestly don't see why it would be cast whole though. I tried it before experimenting with that method early on, and it's doable, it's really hard to produce even results with it.

 

[Mouse Vader]

This is very interesting. I don't quite get how you would make a mould from that particular one piece round pattern if it was solid. It would be very useful to know. All reference I came across when I was self teaching had 2 piece patterns. The ally sabers quality clearly show to me they were cast by someone who really knew their stuff.
Steven giunta: Unfortunately the video you've chosen to demonstrate this doesn't. At 1.50 he clearly 'glues' on the other half of a 2 piece master. I'll have a look on Ytube see what I can find.

 

[Mouse Vader]

I think this is exactly what happened with the original.

So you're saying it was turned as a solid then cut in half ?

 

[teecrooz]

There was likely another wooden buck. I don’t know how else the wood grain would be visible in the picture below, because that would be the inside of the handwheel on the wood buck we have pictures of.

 

[Mouse Vader]

Spent nearly 1 1/2hrs looking on ytube for someone casting using a one piece pattern. Closest I could find are what are termed pattern boards. These either have a pattern on each side for drag & cope (bottom & top mould halves) or have separate boards for the drag & cope. Also learned that the 'green' in greensand refers to it being damp & nothing to do with it's colour.

PoopaPapaPalps you may be interested in what they do at 11.50 in this last video.

I also don't get how a one piece pattern could get out of register.

& Please I'm not out to pick a fight here just sort out what's going on.