Cast Turrets, Etc.

[Legendary]

Thom -
            I have never used Print-a-Part. Since I knew there was interest in it I recruited them to do a seminar.
I agree with you though- the 3D programming is the most difficult hurdle to get over.

When you said this, "JG if you can create the model I would be happy to have the part made for you, or if you can get the plans I would be happy to create the model for you and have the part made."

Do you have access to a stereo-lithography machine? Can you do this type of programming?

I am interested in learning more about SLA.

Steve

[tlivancso]

Hello Steve,

I talked to the Print-A-Part guys at the 2006 IPMS Nats and found out at the time that the little engine block they have as a display piece cost around $65.00 at the time.

There are a few different ways to do 3D prototyping and SLA is just one kind. I have been a mechanical designer doing 3D modeling for over 23 years.
I am also responsible for the 3D printer in my company. It is a process based on a powder and liquid binder combination.

The machine is one produced by the Z Corporation in Boston http://www.zcorp.com/.

Let me know what else you would like to know and I'll do the best I can to answer them.

Cheers,
Thom

[neverbuild]

Thom:

So is it possible to produce a part from a four view drawing like those in a Hunnicutt book?

JG

[tlivancso]

Hello JG,

Which Hunnicut book are you refering to?

Cheers,
Thom

[neverbuild]

Any of them really, but for sake of discussion, let's say the Firepower book.

JG

[tlivancso]

Hello JG,

Okay I have that one (I think I have them all). I will look at the drawings there and let you know if this can be done.

Cheers,
Thom

[Legendary]

Thom-
           that is helpful!

Lets just say for the sake of discussion that the Turret that JG wants to make can be made using Stereolithography, FDM etc. 
Step 1. the 3D drafting  Step 2. someone makes the part (Print-a-Part being one company) Step 3. the printed part is "finished" meaning the ridges you described are smoothed over. Step 4. make a mold and copy the part in resin.

I can do Step 3 and 4. Step 2. is affordable even if JG's turret example was $200 (approx. 3X $65), that spread around among even as few as 10 copies is not much.

It is the 3D drafting which is the real unknown- can you look at a part and ballpark the number of hours you would have in drafting?- or is it one of those things that you can't really tell until you dive in?

I am speaking in generalities. Don't worry I am not going to start mailing you drawings  :)Just trying to learn.

Thanks, Steve

[tlivancso]

Hello Steve,

It really depends on two key items.

1. The complexity of the shape to be created.
         A constrution made of plates is going to be easier to model then a cast construction.
         A cast construction requires the creation of surface modeling which requires a wire mesh to be created from 3D points and then a skin is applied.

2. Accurracy and availablity of reference material.
        On a cast turret I would need at least 4 views, more is better. Because I would need to use the hull design method you described to create the 3D mesh of what I term complex surfaces.

So time wise it could be as low as 4 hours to upwards of 40 depending on complexity, reference material, and how much pre work needs to be done.

hth,

Cheers,
Thom

[Legendary]

Very Cool Thom-
                       thanks for the info.
 Now I need to find a college student who is working with this software and would love to draft a bunch of tank parts in exchange for beer money.

Steve