Equipment

Step 1: Locating your 3D part file.

Your part file can be found by going to the Printables 3D Print Catalog. 

Using the link, browse for the part by name and part image.

Step 2: Printing your part 

Once you locate your part, you will need to provide the specific link or part file to the individual who will be printing it. You can download the part file from the ‘Thing Files’ tab on the part page.

There are many resources for having your part printed again. Shepherd has partnered with the organization Makers Making Change to help provide individuals custom made solutions to their needs. If you go to the Makers Making Change website, create an account, and submit a build request, someone will accept and get in touch with you to help print your part.

You can also contact local maker spaces, high schools, and some libraries that often have 3D printers and may be willing to help you print the part.

As a last resort, there are many online paid services you can utilize to have your part printed. They can be expensive but offer the benefit of printing in high strength materials, meaning your part will last much longer.

Online Services:

• Shape Ways website
• Proto Labs website
• Hubs website

Step 3: Get your part!

If you have any difficulty with finding or printing your part, you can contact the Shepherd Center Makers Making Change chapter at MakersMakingChangeChapter@shepherd.org. 

Homemade Pren-Thomas Laptray

Supplies

All supplies can be found at your local hardware store with the exception of the plexiglass solvent acrylic glue that can be ordered online. Supplies include:

• A Plexiglass sheet 3/16 inch thick. (wood can be substituted if needed)
• Plexiglass glue: Weldon IPS #4 Solvent Plexiglass Acrylic Glue is recommended for adhering plexiglass. It can be ordered online through a variety of sources. This is an optional supply depending on if a ledge is being applied to the bookshelf tray top.
• Sanded Plywood: 1/2 inch thickness is recommended to safely fit under wheelchair cushion if making base out of wood rather than plexiglass. The wooden block will also be used to secure the flagpole mount to laptray shelf. 
• 2 Angle adjustable flagpole holders: It is important to get the holders that have an adjustable angle to allow for the position of the laptray to be customized to each individual. 
• Dowel Rod: Roughly 1inch diameter will be needed, but make sure to size your dowel rod to fit your specific flagpole holder. 
• Screws: These are optional depending if you choose to make a plexiglass or wooden base. Screws may also be needed if attaching the laptray shelf to the flagpole holder with screws rather plexiglass glue.  
• Paint (optional)

Procedure

Creating the laptray shelf: 

• Table saw used to cut plexiglass
• Laptray must fit within armrests of wheelchair
• Bookshelf lip is an optional addition which needs to be cut to size and adhered with plexiglass glue.
• Round and sand edges to prevent any harm
• Miter saw can be used to cut down the edges and then smoothed down with a hand sander.
• Plexiglass glue can also be used to add on a bookshelf lip. Follow instructions on packaging. Clamps can be used to ensure proper placement of the lip onto the tray. This should be set to dry for 24-48 hours.

Cutting plywood or plexiglass for stable base:

Our base design was 18" wide by 7.25" deep with the tongue measuring 12" in depth. 

• The mount should stick out between the users legs without rubbing against skin.
• The width should be the same width of the cushion and the depth should be short enough that it ends at the mid thigh so it doesn’t add additional pressure to the sit bones. If fabricating a wooden base, be sure to sand and bevel wood to prevent rough edges and increase ease of sliding device under cushion.

Laptray Center Mount:

Made out of plywood, use screws or contact cement to attach to plexiglass tray

• Mount flagpole holders to base using a drill and screws.  
• If you choose to glue the plexiglass laptray shelf to the center mount follow instructions on contact cement packaging to securely adhere laptray shelf to center mount.  
• Select the desired height for the dowel rod. The dowel rod should be a snug fit into the flagpole holder, use the knob to tighten the dowel rod into place at desired height.
• Allow the laptray and mounting system to dry over 24-48 hours prior to use.  Dycem or Velcro can be added to the top of the tray to attach needed items such as phone or tablet.
• Prior to user getting into the chair, place the base of the laptray system under the cushion, using caution to prevent any damage to chair or cushion.
• Finally, be sure to adjust the flagpole holder at the base and mount to ensure accurate placement of device according to the users’ preference once the user is safely positioned in the chair.