Hadley Instructions v0 - 5
Hadley Instructions v0 - 5
Hadley Instructions v0 - 5
REFLECTING
TELESCOPE
Assembly and use guide
"Hadley 114" is built using three main Outer diameter needs relatively tight
rods, which should be ½" in diameter tolerance to slide printed parts on
and ideally 36" long
If buying rod or tube from a hardware
Excess rod length is acceptable, with store or other in-person location, it is
a practical minimum of ~33" (850mm) recommended to bring a test fit part
(see 2.3.1) to check fit of rods with
The intended material is aluminum printed parts
solid rod, but aluminum tube (2mm
wall, ½" outer diameter), steel rod or NOTE: ½" EMT conduit pipe
tube, carbon fiber tube, and even is actually 0.706" outer diameter,
wooden dowels have been used in and thus cannot be used with this
builds by community members project's standard models. Adjusted
and remixed CAD (not currently
available) would be required.
1.4: ADHESIVE FOR MIRROR ATTACHMENT
This section lists the parts which need to Do not scale the prints excessively. With
be printed to assemble a Hadley 114 proper print settings, scaling shouldn't be
telescope required, and scaling more than 1-2% can
cause issues with fit of purchased parts
Parts marked "BLACKOUT" should be like eyepieces and nuts
printed black if available, other parts may
be printed in any color desired (see Part 3 Recommended print settings:
for further discussion of blackening) 30% cubic infill
The design allows printing without 4 perimeters (0.4mm nozzle) OR
supports for most materials on common 3 perimeters (0.6mm nozzle)
machines Whatever layer height makes you happy
& works with your nozzle
Telescope prints excellently in PLA, and
has been printed successfully in PETG and
ABS, though those materials have their
own challenges (temperature control and
dimensional accuracy)
Note: The way to stronger prints is "more perimeters" rather than higher infill.
2.2: TEST PRINT & ANALYSIS
Test print shown can be used as a quick If fit is poor, check for over-extrusion in
check of rods acquired from a store or print settings, or "elephant's foot" in
vendor before printing all parts initial layers of print which can be
adjusted in settings or fixed by
Rod should fit smoothly into large hole sanding/filing the lip of the hole
with some slack, gap of 0.5 to 1mm
Also check a #10-24 nut and screw fit
pocket and through-hole respectively
With screw tightened into nut, test print
should lock in place on rod
https://commons.wikimedia.org/wiki/File:3D
_printing_calibration_elephant_foot.svg
2.3.1: PRINTED PART LIST
Sights (lower and upper): Orientation Bearings: These are mirrors of each other;
matters, pay mind so sight needles print the combined file, or individually. Just
are not floating on your printbed. don't print the same one twice!
Lower Tube Assembly (LTA) Housing Upper Tube Assembly (UTA) Housing
The three on this page are the parts
you want interior-blackened
Baffle: if you have an i3 ("bed-slinger") Knobs (print three of these), OR you may
printer, be sure to orient this Parallel to purchase #10-24 wing nuts, thumb nuts or
the y-axis motion. Your bed adhesion through-knobs instead
needs to be good for this piece
These prints have a "sacrificial" layer for
This part can be colored, but the clean bridging above a hexagonal cavity
inside face needs to be black
During assembly, you will "punch through"
this layer with a screw
2.3.5: PRINTED SPIDER
Spider (PICK ONE) There are several to choose from. The
spider selected changes how stars will appear (see below).
This effect is minor for planets and the moon, and spiders
can be interchanged on Hadley 114
This guide will use the single-curved shown at right
Unless you choose a slot-in remix, you need to add
a "pause print" in your slicer application, at the top of the
hexagonal cavities
After pause, insert nut and ensure it is flush with the layer.
Resume print and monitor for adhesion for next
several layers
2.4: OPTIONAL ADDITIONAL PARTS
These parts are best printed in black (matte These parts may be printed in any color, but
is preferred, though glossy is acceptable) or should be blackened as shown on the next
fully blackened on all surfaces: slide for best results:
Focuser drawtube (interior) Upper Tube Assembly (UTA) Housing
Secondary holder Lower Tube Assembly (LTA) Housing
Spider of choice Middle Tube Assembly (MTA) Ring
Light baffle Light baffle (if desired to match color of
upper tube assembly exterior)
Primary mirror holder
If the parts from the first list are printed black, Hadley will function if only some or even none of the second
list are blackened, but the telescope will be more sensitive to stray light particularly in daytime observing. If
required, blackening can be done as a later modification for all critical parts.
THIS IS A MODULAR TELESCOPE, YOU CAN ALWAYS FIX OR SWAP THINGS LATER
3.4: BLACKENING THE PARTS
The parts shown below should have the interior • For baffle, choice of printing in black, fully
surfaces blackened with a brush and ink or paint, or blackening all surfaces, or printing in color and
masked & sprayed with black spray paint blackening inside
Printing in black (whether matte or glossy) is an • Baffle is the second most critical part to
acceptable substitute if you don't want a colored
exterior blacken, even before MTA or LTA
Middle Tube
Assembly
Lower Tube
Upper Tube
Assembly
Assembly
3.5: PREPARATIONS COMPLETE
Parts required for this are listed below When complete, this produces the
"Lower Tube Assembly" which will
support the primary mirror and attach
it to the three main rods
Primary (3x) Collimation
Mirror Cell Knobs
LTA
Housing (3x) #10-24 Nuts
(3x) Springs
(3x) #10-24
Locknuts (3x) #10-24 Screws, 2-Inch
4.2: PREPARING PRIMARY MIRROR CELL
• Blackening of the primary cell is not critical, the • Insert three nylon lock-nuts to the cell.
mirror covers most of this piece. (Note gasket orientation—rounded side
with gasket down)
• Blackening the outer ring is sufficient
• If you don't have locknuts, see appendix.
4.3: PREPARING THE PRIMARY KNOBS
• Find the three knobs, insert one standard nut into the • Find lower tube assembly
hexagonal pocket, then screw one of the long (2"+)
machine screws through each knob • Seat knobs
• Don't tighten the screws fully, leave space as shown. • They should fit freely
3x
4.4: ASSEMBLE PRIMARY COLLIMATION CELL
• Slide a spring over the three loose • Push the cell down over the springs, and tighten
screws (spring should fit freely) the screws into the nyloc nuts using a matching
screwdriver or allen key
• Carefully position mirror cell over the
three screws • Just a few turns should seat each screw into the nut
4.5: FINISH PRIMARY COLLIMATION CELL
• Once all three screws are seated, tighten • Test the knobs turn freely, and clear the holes in the
each bolt further LTA for the rods
• Ensure ends of bolt remain below the level of • Note adjusting the knobs compresses the screws,
the end of the nut—it is acceptable if the bolt adjusting mirror position in/out and angle
is several threads below the end of the nut
• Precise setting of the knobs is not critical at this time,
and will be handled in collimation
• Lower Tube Assembly is now complete, and can be set
aside until final assembly begins
PART 5: MIDDLE TUBE
ASSEMBLY
5.1: MIDDLE TUBE ASSEMBLY START
Middle Tube Assembly, also known as the If a tripod mount is being used as an interim
"mid-ring" or the "altitude bearing," solution, consult appendix for discussion of
provides a mounting spot for the two how to supplement or replace the MTA with
bearing wheels which allow it to turn on a a tripod mount
mount
Completed Middle Tube Assembly:
Uses components listed below
(8x) #10-24
Screw ¾" Long Left & Right
(8x) #10-24 Nut Crescent Bearing
Middle Tube
Assembly Ring
5.2: MIDDLE TUBE ASSEMBLY
• Test fit crescent bearings to the sides of the Middle Tube
Assembly ring
• Note the curved surfaces, make sure the fit is perfect and the
bearings are in the right orientation. Bearings should be flush
The secondary mirror cell consists of: Secondary Mirror Cell Parts List:
(1x) 2" Long
1. Secondary mirror holder—supports
#10-24 Screw
the secondary mirror at an angle
(3x) #10-24 Screw, At
2. Spider—holds the Least Length 1 ¼"
collimation assembly and mirror in (Ideally Thumbscrew)
the middle of the telescope
(1x) Spring
3. Collimation assembly—bolts used Secondary
for controlling the position of the Selected Spider Mirror Holder
secondary holder
• Thread nut over screw until nut is jammed against • Find the spider and place center hole of spider
head of screw. over end of screw, ensuring spring remains
between spider and secondary holder
• Insert screw and nut through secondary holder.
6.3: SECONDARY COLLIMATION CELL
• Twist a nut over the exposed screw • Pushing on screw or secondary holder should
allow slack to tighten nut and adjust position of
• Ensure it sits into the hexagonal cavity secondary.
in the spider. Cavity is larger than nut,
and nut should be free to wiggle • Adjust nut enough to tension spring, fine
without spinning adjustment of position will be carried out later.
6.4: SECONDARY COLLIMATION CELL
• Add three secondary collimation bolts. • Screw partway through the spider
• Long thumbscrews or socket head screws • Leave a gap between screws and the
are ideal, but any long enough screw works. secondary mirror holder for now
Note Gap
6.5: SECONDARY MIRROR CELL COMPLETE
Upper tube assembly attaches the This will show the basic printed helical
spider to the rods, and contains the focuser. Some additional focuser options
focuser, which is where eyepieces are discussed in appendix which require
will be mounted and allows slightly different assembly
adjustment of the focus of telescope
(2x) #10-24
Thumbscrews
Gather the UTA, MTA, and LTA and Insert three rods into holes on LTA, allowing
Three (3) ½" Rods or Tubes. (If using enough excess to be longer than collimation
metric, 12mm rods.) bolts. Measure excess to have same amount
of excess on each rod.
Slide MTA onto rods, positioning Locate lower sight and slide onto one
roughly at middle. (Precise position rod as shown.
will be set later in balancing.)
Attach to rod with one nut and one
Attach to rods with three nuts and short (½") screw. Precise positioning
three short (½") screws in pockets as will be set later.
show, similar to with LTA.
8.5: BAFFLE & UTA
Slide baffle onto indicated rod, note position If alternate orientation of UTA and focuser is
opposite focuser hole in UTA. Attach with one nut desired, move baffle and UTA to alternate
in pocket and one short (½") screw as shown. arrangements as shown later in presentation.
Slide UTA onto rods, aligned as shown relative Slide upper printed sight onto same rod as
to baffle. Attach with three nuts and three screws lower printed sight, and attach with one nut
as shown. Positioning will not need to be precise and one short (½") screw.
and will be set in focusing later. Leave gap
between UTA & baffle for now.
8.6: MIRROR GLUING—PRIMARY MIRROR
Place three dots of glue (~¼") on pads as If possible, have a second person hold
shown. the telescope, reach up through the primary
cell, and use your other hand to lower the
Carefully lower mirror onto cell. mirror onto the first hand.
Be very careful to never touch the reflecting
surface of the mirror. Clean rubber/latex gloves
may be useful.
8.7: MIRROR GLUING—SECONDARY MIRROR
After mirror adhesive has been Pocket positions will only allow
allowed time to cure (1-2 hours) insert one orientation.
spider and secondary mirror assembly
into Upper Tube Assembly Attach with 3 nuts in pockets and
three short (½") screws.
8.9: OPTICAL TUBE ASSEMBLY COMPLETE
Screw two outer collimation bolts on Looking through eyepiece, adjust collimation
the spider until they touch the mirror bolts until view of primary is centered in
holder. Further adjustment of these secondary as shown below
will now adjust the angle of the mirror
as shown on slide 9.4. Once centered, adjust third
bolt to touch and stabilize
Angle of secondary adjusts what part of secondary holder
primary is visible as seen below.
9.6: ALIGNING THE PRIMARY
~26.75"/68cm
In aiming up/down ("altitude)", the Loosen screws on the middle ring so it can
telescope functions like a see-saw, slide freely. Insert eyepiece.
with its fulcrum at the bearings
Rest telescope on flat surface
To balance the Hadley, the
middle ring (or tripod mount) should Adjust center ring until it balances, resting on
be at the balance point only the bearings.
Tighten screws. Your scope is now balanced!
9.10: ADJUSTING SIGHTS
Insert lowest-power eyepiece into the Adjust lower sight up and down on
focuser and point Hadley at rod until lower sight and upper sight
an identifiable target (such as a tree, circles are roughly the same size
building, or the moon)
Rotate lower sight around rod until
Loosen the screws on the lower sight the two rings capture the same image
as seen through eyepiece. Tighten.
Locate eyepiece target
with identifiable context Adjust lower sight to match Rotate on rod to capture
(Note eyepiece view will upper sight circle size target seen in eyepiece
be inverted)
9.11: CONGRATULATIONS (AGAIN)
1.25" is a common standard, and good 2-inch eyepieces require a large secondary
eyepieces are "future proof" even if to illuminate the off-axis parts of the field.
you get a nicer telescope (Effect of undersized secondary below)
2" eyepieces exist; Hadley cannot Larger secondaries (slightly) worsen
use these. This is for several practical contrast, however.
reasons, including the illumination
profile.
Quality is unrelated to barrel
size; most 2-inch eyepieces have 1.25-
inch cousins that are just as good.
2-inch eyepieces are a consequence
of internal optics size; very wide fields
require a larger unobstructed path.
A.3: FIELD OF VIEW
Comes in Hadley kit, roughly $20 USD This eyepiece is the best you will find
for $12 USD. It works but softens the
Sharp, good all-round eyepiece image.
FoV tends to be ~50 degrees (often Recommended minimum-cost option
mis-stated)
Recommended mid-cost option
32mm Plossl
Slightly pricier than the 25mm, costs
$25-30 USD
More "zoomed out" for easy finding
A.5 BUDGET HIGH-POWER EYEPIECES
These two have the same internal 9mm makes 100x power and 0.68
optics, but are listed differently degrees true field of view
They come in 6, 9, 15 and 20mm; 6mm makes 150x power and 0.44
the 6 and 9 are much better than degrees true field of view
the 15 and 20
6mm gives more power for larger
Redline: "68-Degree Ultra Wide views of planets or lunar features but
Angle)" smaller field of view makes finding
targets more challenging and motion
Goldline: "66-Degree Ultra of objects across the sky cross the
Wide Angle HD" view faster - requiring more frequent
adjustment.
A.6 "FANCY" GLASS FOR SPECIAL EYES
These are the "Rolls-Royce" of Hadley eyepieces, and very future-proof for
use with larger telescopes. Given expense, consider deferring as an upgrade
to initial kit, but very worth the money if you stick with the hobby
A.7 HIGH POWER/ EYEPIECES TO AVOID