Hey, here is a chain and sprocket drive for the "Galloping Goose" I want to build. Anyone have any ideas on how to scratch this baby? When I say ideas I'm actually meaning "easy"...."lazy"....."people with little skills and no imagination" ideas. Scale will be HO or 1/72....whatever works.



Oh, did I mention that I need to do this scratch on something like a $3.00 budget?

Hermon

On a $3 budget, I have to say there's only one way. Make your measurements, draw it on some .020 plastic sheet, and carefully cut out the chain and sprockets as one piece. Then, use .010 plastic to add the outside links. It'll take some needle file work, but, it's do-able.

Cuhail

Hermon

Is this going to be a static model or on a railroad layout?

If it is static at HO/OO then the chain is going to be very thin and could be achieved by taking a basic thin square section of plastruct and indenting the chain link texture on the top and bottom surfaces and on the two sides. Then forming a bend for the sag between the two wheels formed by discs and toothed discs with teeth missing where the chain links would be.

Nige

Why don´t you take a look at some after-market motorbyke chains ? I know there are some available...don´t ask me where, but I know they exist !

.

its easy..

try to find any little toy that you have to "wind" up..or a servo motor or a old watch ....
you will find the gears inside there.
as for the chain .........thinking.............still thinking..........
......in 1/72???.......thinking.........thats small!..
any little thing will do at that scale you don`t see the chain parts....
but i will get back to that one..

chris

Hey thanks for the ideas guys. I experimented a little tonight with what I had on hand. I had some left over evergreen stock so I heated it just a bit and got the basic "drooping chain" pattern pretty easily. What to do about representing the individual links is still up in the air.

Hermon

At HO or 1/72 scales, look into the 1/35 bicycle kits by Tamiya and Dragon and Italeri.

For quick cheap molds and casting, I buy the silicone gasket material in the tube to make the mold. Then cast with A+B epoxy glue bought at the same .99$ store.
I don't know about this rail car and the sizes of everything in scale.
Another kit with chains and sprockets are the Monogram Mack Bulldog truck 1/24 kits.
http://www.chuckbush.com/images/mack1.jpg

http://www.geocities.jp/d_force_net/Car/MONOGRAM/7539.JPG

http://www.artecar24.com/UserFiles/File/mackacbulldog/bulldog12.jpg

KSO, I'd like to try that sometime....really. Is there a release agent of some type you use to seperate the hardened epoxy from the silicone or am I completely off base? And, is the actual prototype that you use to make the original mold destroyed or can it be used over and over? I wonder if this method would work for small delicate things like machine gun barrels and such.

Hermon

I have a can of industrial mold release in an aerosol can. I spray it in lightly. If you do not want to use any mold release, then you can still get about 5 casts from it before it deteriorates. Also depending on the degree of detail.
The master part can be removed intact, once the silicone has set. For that chain and sprocket part, I would make a two part mold. I did a very similar thing for my Cranemobile model. I'll take pics of the mold and post here. It's as ugly as your cheerleader photo but it worked fine.

Well, my mom said I was a beautiful baby. Don't know where I went wrong. Say, the chain and sprocket on your cranemobile....is it kit or did you cast it?

Hermon

It was cast from a kit part using the method and materials as described above. Sorry, I didn't get time today to take pictures of it yet, but I will.

Hehe.....I did a google for 1/72 scale plastic chain and sprockets and it sent me to this thread.

I did have some luck on the sprockets. I took apart one of my kids old wind up toys from McDonalds and there are a couple of plastic gears in it darn near perfect scale. Now, the chain.

Hermon

I'll take pictures of a couple 1/35 bicycle chain and sprocket kits and post here. I think that will work for you because the train chain is much bigger, so it might translate down in scale.

These are two kits I have. The Tamiya doesn't have the chain detail that the Dragon kit has. This might be a source for your chain and sprocket for your project.


Dragon bicycle chain next to an HO scale truck and wheels.


Tamiya bicycle chain

... and this is the silicone gasket material from a dollar store which I made a two part mold of a chain and drive ring part. The part came from the old Monogram Mack Bulldog logging truck.


I made a mold because I needed 4 of the front part of the chain loop with the smaller chain drive ring. I casted 4, (actually a few more attempts until I got it right), then cut and glued the halves together at a chain link that looked correct visually. Very similar to what you will need to do to make your drive chain.

I can see exactly what you're saying now. I appreciate you taking the time to post the pic's as it is easier to understand. I have actually found a few sprockets from toys that are almost perfect in scale. The chain is still getting me hung up though. At least if I have to buy a bicycle kit I'll know how to easily cast the parts now.

Thanks,
Hermon

I'm not sure how close this would be to your need, but I found this on Grandt Line's website (www.grandtline.com):

http://www.grandtline.com/images/quarter%20inch/100s/42.jpg



It's 1/4" scale, but it doesn't appear to be for the trucks on a train car. And it's $3.50.

Good luck!

Hey Jeff thanks for the link. I'm not done looking at that site yet but it looks like I could make that work. Cool.

Hermon

Actually, that site is awsome. I've found a bunch of stuff I can use and most of it is listed at really low prices.
http://www.grandtline.com/index.html

Thanks again Jeff,
Hermon