Molding Toneboard Inserts

[dogcatcher]

I was wondering if anyone knows how to make a mold and cast a toneboard?  Not the expensive way like the big companies do, just a homemade version.  The big boys have $10,000 to have an injection mold made, I don't so anybody out there that has the know how and is willing to share?

Marvin

[Braz]

Marvin, that is a darned good question and I will be interested in the responses.

[dogcatcher]

Braz, I will be interested in some info too.  Kind of doubt if I will get what I want.  I know it can be done because I had some boards molded, here is a photo of them.


Those are predator call boards, but now I want to mold a duck call insert, and I want to do it myself, or at least be able to do it.  I have read everything I can find, and I believe I have the theory down.  But I cannot find anyone that I can talk to and ask questions.  I could just jump in and try until I get the result I am looking for, but would prefer to jump in swimming and not drowning.   If I could find a forum on molding and casting I think I could get into this without a major fiasco.

Anybody?   Any help????

Marvin

[Troy of Run -N- Gun Game Calls]

I was checking into this also.This is what I found.http://www.grstools.com/accessories.html

[Al_at_THO Game Calls]

Until I scrolled down and took a look, I figured you were hitting the bottle or something there Try LOL

You know, I have been to that site so many times for my wood carving and engraving supplies and I never once noticed that was there.

I think the big deal is getting the air bubbles out of the mix.  There may be an answer to that over on the Penturners.org site.  They have a pot set up that they use to cast blanks.   I am going to have to check this stuff out myself.

Al @ THO

[Troy of Run -N- Gun Game Calls]

No, I don't drink no more Al.Give that up some years back it got me into to much trouble.I have not tried this stuff but going to give it a try.I also came across a cool product it is call cast ivory used for inlays, you can cut a inlay on wood like a animal and mix this stuff up and pour it in it hardends up turns ivory color.You can carve it.I watched a dvd of this product it is very cool.One more thing you need spell check because my spelling sucks.Sorry for hijacking your post dogcatcher.

[dogcatcher]

Have the sources for the resin and the RTV for making the molds  Problem is how to make the mold so that I can get the board out of it after it is molded.  The Alumilte is pretty good stuff, but also the most expensive, so I plan on using the resin called Similar.   The RTV. room temperature vulcanizing, can come from several places, Micro Mark has a decent price on it as does J Geer. 

The sources for the supplies and the basic instructions is readily available.  The problem is the procedures of making the mold and then casting since this has what the mold makers refer to as "negative rake".  Not sure exactly but that refers to the the design not being simple enough to pour in one piece and then pull out of the mold.  As in the hole for the tone channel, the flared bell, the cork slot etc..

Penturners forum was a flop, all they know how to do is cast pen and a little larger blanks, things that do not include any detail such as a toneboard.  They have all of the info as to how to eliminate bubbles etc. but they just don't get into casting anything except for pen blanks.

What I need is a mold making and casting forum, but I have not found any such animal.   I know that there has to be something out there in cyberspace, I just haven't found it yet.

Marvin

[Troy of Run -N- Gun Game Calls]

What if you take a tone board that you can you can waste,make a box out of wood or something and cut in half.Pour half of it, place in your tone board install the other half of the box with a hole in it then pour that half.Then cut this mold in half,drill a fill hole.Think that would work.That was what i was going to try,when i get my shop put back together.

[dogcatcher]

I thought of the sacrifice of a toneboard, but from all of my reading there has been no sacrifice of the master.   All of the masters were kept, and in some cases were worth fortunes, so I figure there has to be a way to save my toneboard.  The toneboard will have a lot of hours invested in it, it has to be as perfect as possible.  A simple toneboard will take an hour, but a polished and refined toneboard may have 10 or even more hours in it.  One thing I did find in all of the research was the a flaw will be the thing that stands out and everyone else notices.  As of now I have about 5 hours of fine sanding the slope and testing the sound with 5 different reeds.  There is no telling how much more time I will have invested in the master.  So cutting it in two pieces is not even considered an option.

Marvin

[hillbillie82]

guys/girls  i have thought about this b4 too

the way i come up with is this:

make a little box that you can fit your insert in only open on the top put it on the table open side up. you will prob have to fill the tone channel with somethin like wood putty at first and coat your whole insert with beezwax smoothly. figure out a way to make the insert stand up in the box with the exhaust facin up(*) and pour around it. your want the mould to come up even with the end of the exhaust so you will be able to pull it back out.  once it hardens you shuold be able to pull the insert out. if it is a simple design(* usually bigger at the exhaust and tapered down to the other end)  it shouldnt grab or stick to anything.  then you can cut the empty mould in half the long way.  now you can cast your inserts and only have to make the tone channell and finish the end or you can go a little farther.

the only way i can think of to get the tone channell and this is just the tone board side of it is:

if you take the top of your mould (the side that shows your tone board curve) drill a hole down to meet the tone channell.  first you will have to clean the putty out of the channell that you put in origionally but you want to close the channell off at the end of the cork notch farthest from the exhaust. now clamp your insert in the top of the mould.  you should be able to pour some more of the mould matierial down the hole that you drilled to fill the tone channell up to your cork notch and let it dry.  now when you cast your insert you will need to place a peice of mylar between the to halves of your mould to account for the thickness of the saw blade. pour and seperate then all you have to do is finish the exhaust end and drill to meet your tone channell.

this is all a rough idea i havnt tried it so no gaurantees but hopefully you can pull something out of this long winded reply to aid your ideas

one drawback to this is that if you have a lanyard groove or just deco grooves in your insert you will have to fill them with putty as well for makin the mould      ??? :-\ :-\

[dogcatcher]

I thought of the method you described, but the detail in the board will not let me mold it that way.  The insert looks like the one on the left, with the lanyard groove, the inside of the exhaust and the other parts that will keep it from being a simple in and out of the mold are the problems.

Marvin

 

[GN-1]

Marvin,
   This is a little off subject, but your post raised a question in my mind. I have a friend working on a router blade to cut his toneboard shape. He is pretty close and will cut the cork notch by hand. Maybe you could pour a solid insert and do something like that? Not trying to hijack, just throwing out an idea. Shawn

[cb223]

I am a mold maker by trade. I build plastic injection molds. To mold that tone board would require a fairly complex mold. I would think it would be pretty tough to do without a full machine shop at your disposal.

 You would need an insert(slide in a production mold) that went through from the exhaust to the end of the air channel and another that came in from the tone board side to make the cork groove. The rest of it would be split along the line of the tone board. Another way to put it, the main two pieces of the mold would make the outside and the inserts would come in from the end's to make the undercuts and holes.

I have made proto type molds that the inserts were just pulled out by hand before the part fully hardens.

Most of my work is just in injection molds but I would think the concept is the same. If you have any questions drop me a line, I can try and answer them.

Chad

[dogcatcher]

Thanks Chad, I see where I was lost.  My problem was the inside and how to conquer that opening and still be able to extract the final part.  But you solved that problem, or I should say you convinced me that I am swimming in deep water without a life jacket.  Thanks again

GN-1 to do it that way would be defeating what I was trying to do, but I do see it as a viable option for production models.

Marvin