Q. I just need a simple washer or spacer to adjust image train distance. Can you make this?
A. Washers can be created to fit most male threaded devices. First select the device or feature the washer
must be installed over (this generally needs to be a male threaded device although washers for female features are
possible in some special cases), then select
Washer/Spacer on the other side (washer is listed under the
"extensions and spacers" category). Lastly select the desired thickness for the washer. Please be
careful not to make too thick a washer as the length of thread available on the device to be
spaced-out must be taken into consideration. Most washers are made 1 to 2 mm thick (0.040 to
0.080 inch) at a maximum to leave enough free thread so the device can still be safely
threaded with the washer installed. If you need a long spacer
an extension tube will probably provide a better solution.
We can make washers as thin as 0.5 mm (0.020 inch).
If an error is displayed stating that a washer would not be useful for the selected feature, this generally
means that the feature does not have the correct gender. The selected thread must be male to create a
standard washer, but if the thread has a non-conventional reference point the female version needs
to be selected instead. Check
this answer for more information.
As a practical example selecting a generic T-thread device on the Telescope Side produces a washer with the
appropriate inside diameter to slip over a standard male T-Thread.
Please note however that as a general rule we do not recommend adding washers in an image train
as any additional interface can potentially compromise orthogonality, promote flexure, and decreases
rigidity. It is normally desirable to install the minimum possible number of parts in an image train.
Our Build-An-Adapter web app allows designing custom adapters at almost any length. This results in
very accurate spacing while avoiding stacking extra components.
show
full Table of Content