Pathfinder
Well-known member
Looking good. I love this thread. There is so much potential in this technology. Thanks for sharing!
John Minton
John Minton
Urethane: Materials and Methods
- Thread starter dladcock
- Start date
Thanks John,
I hope some use can be found in the information. I have some projects that will probably be of more interest from a practical home shop/hobby point of view. This exercise is meant to be an overview of the general principles involved. Next time we'll do something really useful (Like make a car part!!!)
dla
2-19-2014
Today I didn't take any pictures, but was able to produce 4 scallops in an eight hour shift. Left one in the mold to cure overnight yesterday, so that amounted to five for the day. The process is streamlined now so, production is pretty much painless.
I had the opportunity to invite Jared at http://www.reynoldsam.com/ in Charlotte NC to drop in and contribute to the thread. Hoping he takes me up on this and corrects anything I might be out of line on.
Currently tooling up for some new projects as well as finishing some old projects. I'll keep you posted as things progress.
dla
Today I didn't take any pictures, but was able to produce 4 scallops in an eight hour shift. Left one in the mold to cure overnight yesterday, so that amounted to five for the day. The process is streamlined now so, production is pretty much painless.
I had the opportunity to invite Jared at http://www.reynoldsam.com/ in Charlotte NC to drop in and contribute to the thread. Hoping he takes me up on this and corrects anything I might be out of line on.
Currently tooling up for some new projects as well as finishing some old projects. I'll keep you posted as things progress.
dla
Streetbu
Well-known member
Nice work!
2-21-2014
Well..... Just for giggles I cast a scallop today using SMOOTH CAST 380. This material is a hard Urethane Plastic with a D Shore Hardness 85. Ran it by the Group leader and our Big Boss and both preferred the harder material over the 85 Shore A urethane rubber.
So, now I'm moving forward with molding the harder material in place of the rubber product. It's much cheaper than the rubber, about 75% cheaper, cures in 1 hour and works just fine with the existing mold. The red color was selected by the CNC guru. I asked him what his favorite color was. Scientific deliberation has it's place.
There are several colors. Red, Purple, Yellow, Green, Orange, Blue, Brown, White, Flesh Tone and a couple more, that escape me at the moment. Tints can be combined to make custom colors beyond imagination. http://www.smooth-on.com/Urethane-Rubber-an/c6_1118_1202/index.html?catdepth=1
If that's not enough for you, there are fluorescent tints that "glow" nder UV or Black Light. http://www.smooth-on.com/Silicone-Rubber-an/c2_1128_1267/index.html
dla
Well..... Just for giggles I cast a scallop today using SMOOTH CAST 380. This material is a hard Urethane Plastic with a D Shore Hardness 85. Ran it by the Group leader and our Big Boss and both preferred the harder material over the 85 Shore A urethane rubber.
So, now I'm moving forward with molding the harder material in place of the rubber product. It's much cheaper than the rubber, about 75% cheaper, cures in 1 hour and works just fine with the existing mold. The red color was selected by the CNC guru. I asked him what his favorite color was. Scientific deliberation has it's place.
There are several colors. Red, Purple, Yellow, Green, Orange, Blue, Brown, White, Flesh Tone and a couple more, that escape me at the moment. Tints can be combined to make custom colors beyond imagination. http://www.smooth-on.com/Urethane-Rubber-an/c6_1118_1202/index.html?catdepth=1
If that's not enough for you, there are fluorescent tints that "glow" nder UV or Black Light. http://www.smooth-on.com/Silicone-Rubber-an/c2_1128_1267/index.html
dla
First, Welcome to The Garage Journal!
I have done some small parts, grippers for pick placer applications, where the rubber part is bonded to metal mounting tabs. The process requires the metal part to be clean, abraded by sand or bead blasting, de-greased with a solvent such as acetone and primed with a bonding primer.
If all the steps are followed, urethane rubber will tear away from itself before there is any separation at the bonding line. As wicked tough as urethane rubber is, that takes some doing.
Some metals, such as stainless steel, don't bond well with urethane. The bond can be enhanced with proper preparation and a Urethane adhesive. http://www.smooth-on.com/Urethane-Rubber-an/c6_1118_1269/index.html
Hope this helped with your question. I'd be interested in the conversation on your Pontiac forum if you could provide a link. Hearing what the rest of the world is working on helps me to improve my knowledge base.
dla
I have done some small parts, grippers for pick placer applications, where the rubber part is bonded to metal mounting tabs. The process requires the metal part to be clean, abraded by sand or bead blasting, de-greased with a solvent such as acetone and primed with a bonding primer.
If all the steps are followed, urethane rubber will tear away from itself before there is any separation at the bonding line. As wicked tough as urethane rubber is, that takes some doing.
Some metals, such as stainless steel, don't bond well with urethane. The bond can be enhanced with proper preparation and a Urethane adhesive. http://www.smooth-on.com/Urethane-Rubber-an/c6_1118_1269/index.html
Hope this helped with your question. I'd be interested in the conversation on your Pontiac forum if you could provide a link. Hearing what the rest of the world is working on helps me to improve my knowledge base.
dla
Thanks for the reply!
The piece I have in mind is what is called various names including torque tube bushing and bearing insulator. The part is used in 1961-1963 Pontiac Tempest driveshafts.
These cars have rear mounted transaxle transmission setups with motors in the car's front end. The drivershafts themselves are round shafts similar to torque tubes and they run inside a tunnel enclosure tube. The driveshafts are held in place within the tube by a couple of bearings that are held in place within the tube by rubber pieces that fit the contour of the tunnel.
The bearings are about 1 7/8" in diameter by 1/2" thick. The rubber pieces have a thin metal ring about the size of the bearing that is "vulcanized" to the rubber. The bearing is "pressed into this thin metal ring which acts as a bearing holder. It is these rubber pieces that are no longer available but there is a demand for them.
As I mentioned, there is a topic on this item in the Performance Years website forum which you may want to look into. The specific site is listed below and a picture of the piece is included in the thread.
http://forums.performanceyears.com/forums/showthread.php?t=745189&highlight=torque+tube+bushing
Looking forward from hearing from you.
The piece I have in mind is what is called various names including torque tube bushing and bearing insulator. The part is used in 1961-1963 Pontiac Tempest driveshafts.
These cars have rear mounted transaxle transmission setups with motors in the car's front end. The drivershafts themselves are round shafts similar to torque tubes and they run inside a tunnel enclosure tube. The driveshafts are held in place within the tube by a couple of bearings that are held in place within the tube by rubber pieces that fit the contour of the tunnel.
The bearings are about 1 7/8" in diameter by 1/2" thick. The rubber pieces have a thin metal ring about the size of the bearing that is "vulcanized" to the rubber. The bearing is "pressed into this thin metal ring which acts as a bearing holder. It is these rubber pieces that are no longer available but there is a demand for them.
As I mentioned, there is a topic on this item in the Performance Years website forum which you may want to look into. The specific site is listed below and a picture of the piece is included in the thread.
http://forums.performanceyears.com/forums/showthread.php?t=745189&highlight=torque+tube+bushing
Looking forward from hearing from you.
AussieDan
Well-known member
Great thread, thanks for sharing your expertise! I can think of a few things I'd like to cast already.
I sent you a PM with some specifics and contact information.
Sure, Dan. I'm currently working on a couple of projects for customers, some of which I have been documenting. These are different than what I've posted so far using urethane rubber instead of castable urethane plastic for the actual parts.
The cool thing about this technology is the fact that imagination is the only limitation. The product lines offer more solutions than I can possibly scope.
Here's an example that blew me away when I began researching casting and mold making and it's just one of many.
http://www.smooth-on.com/gallery.php?galleryid=157
dla
AussieDan
Well-known member
Wow! I spent some time looking around smooth-on the other day and the range of different materials available is pretty amazing. I saw products that would let me cast clear lenses for lights, the obvious engine/suspension/subframe mounts, and even thin-walled parts like air ducts. The options really are limitless.
To be able to reproduce a record and have it play really speaks volumes about the fine detail it's possible to reproduce.
Well, with all the other things that have to be negotiated around day to day living, finally, here's a little update. Aurelius contacted me, worked out the details and someone sent me a model to cast. We turned out the bearing cans and made a mold. Here's the first part out of the mold. (Yesterday) The mold needs to season. After 3-4 pours it will make a better looking part.
dla
Southernbuild
Well-known member
This is awesome! I don't know how I missed this thread 
Very interesting processes, thanks for sharing
Just what I needed, another skill / interest / hobby, Goodbye space, time, money.... lol
Very interesting processes, thanks for sharing
Just what I needed, another skill / interest / hobby, Goodbye space, time, money.... lol
EdT
Well-known member
WOW!! Great thread!! I make lots of repro parts for a friend of mine, but mostly in metal. This opens up a lot of new potential for weird old parts. Thanks for taking the time to post.