Collectors find pleasure in having old items of all types around. Then there are those who collect replicas of old items that are not in use anymore. That’s what Roe Machine found when one of their customers came to them and asked them to design and build a replica of an old mechanical gas pump for one of their customers.
Thanks to ZoomRP.com, Roe Machine was able to produce the head to the actual size of the original gas pump. Fully assembled the part is about 7 feet tall. The head itself is about 1.5 foot wide and about 14 inches deep, and 9-inches tall.
Roe Machine’s owner and designer Keith Rawson typically produces components on one of their CNC machines, but for low volume orders such as the gas pump replicas, he needed to find another method. “A normal order from my customer is about 20 pieces,” Rawson said. “The man who buys the replicas owns a body shop. He sells the pumps once in a while and likes to keep a few on hand. It’s a side business for him,” Rawson explained.
The old gas pumps Roe Machine builds are those originally built anywhere from the 1920s to about the 1970s. They are the rounded-off, mechanical versions seen in old movies. The machines are drawn into Rhino CAD software first. All the dimensions are checked and component fit is double-checked for accuracy. “Rhino even repairs the file if there’s a minor problem that was overlooked,” Rawson said. After producing the 3D drawings, Rawson creates an STL file through a conversion that the Rhino software offers as a standard output.
The head for this older style gas pump was made from five different pieces.
CNC processes would have cost too much to manufacture the tooling in-house.
“We run the prototype through ZoomRP.com’s online service because it’s the fastest service we found, plus the price was the lowest,” Rawson said. The prototype is used to make a permanent tool. Rawson originally thought he would be able to use one of the CNC machines to create the needed parts, but they were too complicated and would have taken a lot of time to fashion. The head for the gas pump was made from five different pieces and would have cost too much to manufacture the tooling in-house. “I found ZoomRP.com on the internet while researching another way. Everything about the service was easy and automatic.”
Stereolithography was used to build the gas pump prototypes.
ZoomRP.com offers a choice of three different materials for any particular prototype a customer might need. Roe Machine doesn’t ‘go cheap’ on anything. Size and quality are what matters, and the size of each component helps to dictate which machine and which material is best for the application.
The components were made using SLA (stereolithography). A vat of photosensitive resin with a platform moves in a vertical motion. The part that is being built at the time rests on the platform while a laser traces the outlined shape of each layer from the STL file. When the laser hits the photosensitive material, the resin hardens and creates a solid layer. The platform moves down for the next layer to be traced.
“We had to do very little sanding and filling,” Rawson said. After those operations, the company cast the part and welded it together. Since there were no moving parts required for the final gas pump, the job was completed. Once Roe Machine ships the final replica, their customer provides custom painting as a personal touch.
“I learned that the more complicated the part, the more cost effective ZoomRP.com became. Simple parts, I can churn out on one of my machines, but complex designs are easier done through the prototyping service,” Rawson said, “and these gas pumps are complicated components. I did learn that their tolerances are always better than what they guarantee.”
The head that Roe Machine produces is the actual size of the original gas pump. Fully assembled the part rises to about 7-foot tall. The head itself is about 1.5 foot wide and about 14 inches deep, and 9-inches tall.
Source: :: Make Parts Fast ::