Final Assembly

These instructions show the assembly for one stage. For any extra stages, repeat steps 2-5 before running the string.

Blue Loctite (McMaster P/N 1004A12) is recommended on all bolts that thread into a tapped hole.

Step 1

Slide the Base Tube for your Telescope into the gearbox. In order to do this, loosen all bolts and remove all #10-32 x 3/8”L bolts. The 4 holes in the Base Tube will align with the holes for the #10-32 x 3/8”L bolts. Once the Base Tube is in Place, thread the #10-32 x 3/8”L bolts back in. These bolts should sit in the holes in the Base Tube and act as pins to prevent the tube from moving. Re-tighten all other bolts.

For the Flipped Gearbox configuration, the Base Tube will be slid in from the opposite side.

Step 2

Slide the correct Top Block and Bottom Block onto the Tube for the next stage being assembled. For example, the images below show the 1-1/2” Tube with the 2” Top Block and the 1-1/2” Bottom Block.

If you are using 1/16” wall tubing, the bottom block must be installed with an appropriate sleeve.

Handle the CF Springs carefully, the edges can be sharp.

Step 3

Bolt the flat tab of the CF Spring through the Tube into the Bottom Block using an Ultra Low Profile #10-32 x 3/8”L Bolt. Repeat this step for both CF Springs in the Top Block.

Step 4

This step is optional. Teams may make the hard stop plates themselves to increase the stability of the telescope when it is fully extended. Using the hard stop will also decrease the overall extension of the telescope.

Pull the Top Block down the tube. Bolt the hard stop to the tube using Ultra Low Profile #10-32 x 3/8”L Bolts. These bolts should thread through the hard stop and into the Bottom Block. The hard stop used must be cut to the same width as the tube it is being bolted to. If no hard stop is being used, just install the Ultra Low Profile bolt.

It is recommended to have another person or to use a clamp to hold the Top Block in place while installing the hard stops.

Step 5

Slide the assembly from Step 4 into the correct tube. For example, the image below shows the 1-1/2” Tube being slid into the 2” Base Tube. Loosen the 4 bolts on the Top Block and slide the Top Block over the end of the larger tube. The 4 unused tapped holes in the Top Block will align with the 4 holes in the larger tube. Once the Top Block is in place, tighten the 4 bolts on the Top Block.

Step 6

Compress the assembled stages from the previous step by hand. Thread two #10-32 x 3/8”L bolts into the top two holes of the Top Block. These bolts will act as pins to keep the Top Block in place.

The #10-32 x 1/2”L bolts will be threaded into the bottom two holes in the Top Block, and will act as the hardstops for this stage. They will have to be installed with one 0.090” thick #10 Washers.

Repeat this step for both sides of the Top Block.

If any of the bolts used in this step rub against the smaller tube while it is moving, add 0.010” thick #10 Washers (WCP-0038) underneath them until they no longer rub.

Do not overtighten the #10-32 x 1/2”L bolts. This may crush the 3D printed spacers and cause the bolts to rub.

Note for Stage 1

If you are assembling the 1 to 1-1/2” Stage without the GreyT Telescope Hardstop, make sure to only thread in the left hardstop bolt in the top block. If both bolts (or just the right bolt) are used, the hardstop bolt may dent the slot for the Bearing Stack-Up in the 1” Tube Bottom Block. This could cause the 1” Bottom Block to rub against the 1/4” ID Bearing, creating unnecessary friction in the assembly.

Step 7

Non-Flipped Gearbox String Run

The string will be attached to the Drum using the #10-32 x 3/8”L bolt installed in Gearbox - Step 1. From there, drop the other end of the string through the bottom of the assembled Telescope and fish it through all the stages. The string will then be tied to the final stage using a 3/8” Shaft.

It is recommended that the spacer used to redirect the string is shortened using a belt sander or lathe until it spins freely when assembled. This will reduce any unnecessary friction on the string run. This spacer is marked in orange in the image below. Do not overtighten this spacer.

It is recommended that the drum should have a minimum of 2 to 3 full string wraps when the telescope is fully extended.

Flipped Gearbox String Run

The string will be attached to the drum using the #10-32 x 3/8”L Bolt installed in Gearbox Step 1. The other end of the string will attach to a custom plate or shaft created by the user.

The string does not have to be run exactly as shown in the images down below. However, the string must be run in a way to ensure that it does not collide with the CF Springs in any of the installed Top Blocks.