Group buy-group pour, bronze 24 PDR Coehorn golf ball mortar

[Double D]

I have been in contact with Cal-e-co Gallery in Cody, WY.  They are interested in adding cannons to their line of cast products. 

I have talked with them about  doing a group pour-group buy for us. They need to know if there is really an interest and in what form.

This poll is only to see if there is an interest not to take orders.   There is no price included in the poll.  I am just trying to gather numbers to see where the interest if any lies.

[Cat Whisperer]

Cast my vote for EITHER as-cast or with finished bore.
 

[Double D]

Cast my vote for EITHER as-cast or with finished bore.
 

Click one, we are doing demographics here not orders

[flagman1776]

finished bore

[keith44]

finished bore, I'm sure I can get prints for a base, and I've seen me finish the OD of other pieces.

[GLS]

Finished bore. 

[DaveSB]

The machining process is half the fun of owning BP artillery, rough casting all the way!!

[Bob J]

My vote is for having the bore finished....  The exterior can be as cast.....

[flagman1776]

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[Cat Whisperer]

IMHO, at the very least the bore & chamber should be finished correctly.  Either bore only or fully finished.  If the bore were not finished, I'd predict a number of them never get conpleted (or somebody could make some money by setting up to complete the bores). 
 
If the budding machinists want to do some turning, most can finish the outside satisfactorily.
 
I think making a functional base should be within the abilities of most carpenders.  It would be nice to have dimensioned drawings.

Good points.

An opportunity for SOMEONE to set up a short-run production line.

[subdjoe]

I voted for fully finished, which I assume is just the tube, not the wooden bed.

I have neither the machiness nor the training to finish something like that.  Well, I suppose I could use files, sandpaper, and the like, but it would probably not get finished.

[Mike H.]

For me it would have to at least have the finished bore, which was my vote. But a lot would have to to with the quality of the casting on the outside. If it is well shaped and just needed smoothing I'd do that. But if the shape was not 90% there, then I'd want someone to turn it for me.

[shred]

I'm in favor of rough-cast and build-it-myself, assuming reasonable cost savings and something I can swing in my lathe (Golf-ball-bore yes, Bowling-ball-bore, no  )

It would seem that's how they come out of the mold in any case, so it would seem easy enough to snag some off the line along the way and send them out in various completion stages if there's enough demand for finished tubes.

Would the trunnions come cast-on?  That would seem to make sense from a casting POV, but it adds a bit of complexity to the outside machining.

[GGaskill]

Since it appears that these would be investment cast, the as-cast finish should be pretty good; not polished shiny but like Ruger unfinished castings.

Would the trunnions come cast-on?  That would seem to make sense from a casting POV, but it adds a bit of complexity to the outside machining.

The presence of the trunnion (and rimbases) basically means you have to hand finish the whole breech end and trunnion.  Here is a not the world's greatest picture of a 1.5 inch bore bronze Coehorn:

[gunsonwheels]

DD:
 
Are these going to be sand cast or investment cast?  I ask because in viewing their website it appears they do a lot of investment casting.  Forum members are all probably aware investment castings can be within a few thousandths of an inch of the nominal dimensions of the part and are usually far more free of inclusions and impurities.  So sand or investment...??

[Double D]

The  Foundry only deals in wax or investment casting.

Drawings are available from  AOP for the tube and base.  The AOP drawing is full scale and would have to be scaled down.

Yes it would be simple enough for a woodworker to set up some jigs and fixtures and knock out some unfinished bases.

This poll is simply to see if there is an interest, and in what form the interest lies. 

I can also tell you that I have been in contact with a world renowned wax carver  to do the initial wax for the  casting. This famous wax carver wants to do this with the bore cast in place which will reduce the cost of finishing.


With the current trend of the poll towards a finish piece I don't any see problems with  some one wanting an unfinished or partially finished casting.
 

[DaveSB]

Idea on price points?

[Double D]

Idea on price points?

That hasn't been discussed yet. 

[gunsonwheels]

GG:
 

Since it appears that these would be investment cast, the as-cast finish should be very good; not polished shiny but like Ruger unfinished castings.

I have a few Ruger's and the investment finish is typical to the finish inside the frame (i.e. inside the opening where the cylinder is).  Unlike the exteriors which are ground (very slightly) and polished, the surface is smooth but dull, like the finish achieved by glass bead blasting.
 
If they are cast finished I'd like one that way as it would be most representative of the originals in its finish.
 
George/GOW 

[flagman1776]

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[Bob J]

Am thinking the same as flagman.....  Changed my original post to "as cast" exterior with a finished bore even though I originally voted to have everything finished....

The quality of the "as cast" exterior makes a huge difference to whether to have the exterior finished.  It appears the exterior quality will be very good...   so a completed bore, as cast exterior makes tremendous sense.

[gulfcoastblackpowder]

The price point would be a significant factor, especially since I am presently between jobs as of yesterday, but I'd lean towards the finished bore/as cast exterior if the price was right.

[Victor3]

 As an investment casting, the bore/chamber could be cast to finished size (no boring required) to keep the cost down. Might want to ask the foundry what they can guarantee on dia and out-of-round. If they can hold +/- .02" you could specify 1.72" nominal dia; that should be plenty good enough for golf balls out of a mortar.
 
 What alloy will they use? The Everdur that Gary's foundry used for the Morko is very good stuff for this application.
 
 BTW, I'm still wanting a 1" LION MORTAR, Gary... 

[Double D]

They use everdur.

[DaveSB]

Since you're seeing a decent interest in these, what kind of ETA are we looking at? Ex: all orders placed by X date will be delivered within 2-3 weeks. And a follow up question, how far away are you from making a deal with the foundry and getting price points?

[flagman1776]

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[Double D]

Question:  What is the scale of these?  1/6th?

As the title says--golf ball scale.

I have sent the wax carver dimensions.  I got the dimensions by dividing the original dimensions by golf ball dimensions.  (5.82/1.723= 3.378)

[DaveSB]

Any interest in a pop can scale model instead, or in addition to? I figure go big or go home

[Double D]

We need to take this one step at a time.  We don't even know if this will work.  What we are trying to determine in what form of casting are people interested.

[DaveSB]

I absolutely agree, and I mean no disrespect. I was just throwing out a few ideas and questions. This sounds like a very neat project and I hope it's a success. If the pricing is right for me, I definately want one. I know a few guys here at work that would also like one.. so good luck sir.