Found Dreaming

I question if you would actually get the sound you are looking for, a casting wont have the same hardness as the cymbols, the cymbols are spun and quite hard compaired to a casting. Maybe cast it slightly smaller then run it thru a set of rollers to expand it to size. This would in effect work harden the casting.
I Love lost wax casting, wonder if you could make a wax pattern then investment cast it? Over all quality would be better than sand casting thats for certain and you wouldnt have to worry about getting the proper draft on the pattern. Dont mind me, I just love to jibber jabber and try to figure out ways of getting things done.

HT1 wrote:I'm limited to a #10 Cucible so about 30 lbs of metal, you are going to need close to 45 to get a out a ring as large as you need. Besides my furnace is OOC right now anyway, it will be up after the new referactory comes in. it is bouncing around in the back of my head for a way to do it that will use less metal, less sand

Less sand could be accomplished by creating an inner border as long as the pour didn't need to run across the bottom. It wouldn't even have to be circular, although the closer to circular the better. Perhaps an octagon or pentagram shaped inner wall, you know, a place to hold your beer....

For that matter, I could make an inner wall when I make the pattern for the shell/casting. Turn it round, maybe 9 or ten inches OD...

DF, thanks for the thoughts, but I am certain I want to sand cast this and the end result (sound) is what I am after. I have 3 cast bronze drums already, but none made by me. Zildjian cymbal company teamed up with a drum company to make these kind of drums around 20 years ago. Now they sell for around $2500 on evilBay. As much as I'd like one of these, tripping over my pile of broken ones and drum building experience tells me, "Hell, I can do this.." I'd even like to help with the casting, if possible.

The quest continues....

Id step away from the sand all together, make a wood drum shell a little over sized and split it into two halves for a pattern. Then use investment and pour an inner and outer mold with the outer being split into two pieces. The split in the pattern and outer investment shell is only to allow for removal of the pattern. using an investment casting like this will allow you to thin the part to reduce the weight for an at home cast and also give a better surface finish. Maybe next year ill have a furnace large enough to attempt something like this, right now im limited to about 12 lbs.

So what are the concerns with drafting the pattern? I'll be honest I haven't had time to read up on the whole process. Is it making sure the liquid has a chance to fill the pattern before starting to cool?

How much shrinkage can I expect?

The reason I ask is that I found a small foundry about 1-1.5 hrs away from me that does lost wax bronze casting. The exception is the owner is a former university music teacher so his interest was peaked when i started to explain what I wanted to do. Of course he tried to talk me into his process, but I think I could talk him into doing a sand casting if I offer to provide everything but the foundry. Which means I'd have to buy some sand/petro bond, making the forms and patterns are not a problem, but I will need to study up on the process.

His way would run me around $6-700 with me making the plaster casts, pattern, etc. He also said I could help as much as I wanted, even holding the handle during the pour.

He seemed to understand my reasoning and we even got a bit side tracked on casting new cymbals...

So far this looks to be the most promising avenue yet...

I jumped the gun a bit with talking about drafting the pattern. The draft is basically a taper in the pattern to allow it to be easily pulled from the mold. With what you are making, and depending on how you mold it, you probably wouldnt need to worry about getting the proper draft on the pattern. If you do decide to go lost wax, you will get a smoother surface finish and would not have to cast the part as thick to allow for machining. 6-700 bucks?? Yikes!!!!! Might as well build your own furnace and just GO FOR IT!!!!

Does seem high for just the burnout and pour but then we are talking about a considerable amount of material here. Using a lost wax process you would not need any draft at all so it would be less machining after.

This was a pair of videos from a few years back that shows bell making, maybe it will give you some ideas. Everyone has some cow dung nearby.
http://www.youtube.com/watch?v=aqjgw3KK ... er&list=UL
http://www.youtube.com/watch?v=C9hixFIf ... u_in_order

Jammer wrote:This was a pair of videos from a few years back that shows bell making, maybe it will give you some ideas. Everyone has some cow dung nearby.
http://www.youtube.com/watch?v=aqjgw3KK ... er&list=UL
http://www.youtube.com/watch?v=C9hixFIf ... u_in_order

Wow, and you guys with all of your fancy tools.... pah!

Thanks Jammer..

Got another quote for $380 to cast with me supplying the pattern and material of course. Foundry in PA. It was $650 for them to make the pattern and cast.

They want to pour it 3/4" thick, and estimate I'd need 60 lbs in bronze. Pretty sure it would be hands off for this place to do it, too. The more I think about it, the more involved I'd like to be.

Still thinking about trying to talk the professor into doing a sand casting...

Or worse yet, build my own... damn you guys!