We got a broken delta belt sander. We didn't know what the problem was, but after gathering the right tools and a bit of part searching and ordering, we could get the replacement parts. Then, after few hours of diagnosis and labor, we were able to get the belt sander up and running again!

Here is how we fixed it.

Step 1: Tools

To be able to get started, you'll need the following tools:

- Screw drivers ( 3 standard sizes).
- A hammer.
- Set of allen keys (different sizes).
- Thin wire.

Step 2: Diagnostic

- First we inspected the power cable. Because the cable was in a good condition, we decided to connect the sander to the power.

- - Once powered, we were able to diagnose that sander belt was not turning but the engine was working fine. The motor seamed to have no load; it was spinning but nothing else happened.

- We decided to open the machine.

- While unscrewing for opening the cover, we realized that one screw was missing. We used an screw of the same size from the robotic life tool box.

Step 3: Opening and Identification of Missing/broken Parts

- To open the belt sander, we turned the machine upside-down and took the cover off.

- Once opened, we suspected that there was something wrong between the motor and the sander belt. However, we couldn't identify right away which pieces were broken.

- We inspected the motor axis with a wire, trying to pull off the loose pieces. Though we were able to identify which pieces were out of place (rubber belt and motor axis cap), we couldn't take them out.

Step 4: Moving the Motor

After the unsuccessful attempt to taking the pieces out using the wire, we determined that we needed to move the motor outside its protective cover. To do that, it was necessary to unscrew the disk that rotates over the machine's horizontal axis.

Step 5: How Could the Wheel Be Taken Off?

Also, we struggled to understand how the wheel could be taken off. We found that it could be unscrewed from the inside. This allowed us to see that the rubber belt was not fixed properly and that another plastic part (motor axis cap) was not properly attached to the wheel.

Step 6: Fidding the Appropriate Rubber Belt

Once we took the loose parts out, we identified that the drive belt was shot.

We did an online search for the sander "model number" and "drive belt" or "rubber belt" or "sander replacement parts". However, we didn't find an exact mach with our model.

Then, we looked at the "rubber belt" specification numbers and realized that it has a standard specification which can be obtained from various online vendors.

Hence, after counting the number of marks on the rubber belt (80), we were able to find the vendors:

McMaster:
http://www.mcmaster.com/#6484k126/=3vj5wp

MikesTools:
http://www.mikestools.com/1347220-Delta-Drive-Belt-for-31-460-SA446-4-Belt-6-Disk-Sander.aspx

Step 7: Installing the New Rubbert Belt

Once the rubber belt arrived, we could try it out on the sander - it worked great!

The pulley was a bit loose so we used an old trick and put paper between the motor shaft
and the pulley.

The pictures below depict the steps for setting up the new belt:

1. (p. 0185):
Old belt vs. New belt. Notice the lack of teeth of the old belt.

2. (p. 0188):
Install plastic pulley on motor shaft. Used paper on shaft to increase
friction fit. Rubber hammer was used to install the pulley

3. (p. 0186, 0187):
Install belt and tighten tension bolt with adjustable wrench.

Step 8: Working Like a Charm!

Once the rubber belt was intalled, we were able to rebuild the sander. It worked like a charm!! :-))

Hope this helps other people!

Ryan, Jerome, Selene, and Ned