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Making a Hand Powered Shell Pasting Machine By George Kenney

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The Nature of This Document

This document is a stepwise explanation of how I went about designing and building a hand powered Shell Pasting Machine. I hope it will inspire others who, like me, thrive on taking an idea, forming an image, then bringing that image into reality. There were several times during the design phase that I thought it was hopeless and I considered scrapping the entire project. I hope others will be inspired to continue when these same feelings overcome them when trying to bring an idea into reality.

I believe man’s ability to create is nothing less than magical. The only difference between this and what Wizards do in the fantasy world is “time”. If you could speed up time, from the point you formed the mental image to the point of final delivery, and others could not see what transpired in between those points, then the delivered item would seem to magically appear. In fact, I’ve called the process “Slow Magic” for the past 30 years. Perhaps we, the Do It Yourself (DIY) people, are wizards in training for wizard-like adventures in a future life. Well, okay . . . back to the Shell pasting machine.

Finally, the best remedy for anxiety when undertaking something like this is planning and design. I probably went through half a stick of soft white eraser sketching out 2D top and side views as well as 3/4 views of the end product. As I repeatedly went through sketching and visualizing the operation of the machine, I would add or remove hardware from my bill of materials. Finally, when the design had stabilized, I began the process of thinking through and writing down the build process. I ordered parts after the design stabilized but I did not cut one piece of wood or metal, drill one hole or assemble anything, until I was able to write down how the machine would be built from start to finish. The process of writing down assembly instructions revealed short-comings in the design. Detailing the assembly resulted in changes to the design that made not only assembly and disassembly easier but improved long term maintenance of the machine. An example of one such design change was introducing both a drive platform and slotting the Rim Frame for Idler Wheel adjustment. These changes allowed the ability to raise and lower the Drive Wheel as well as position the rim to the left or right. This design change will be of great benefit in two areas: 1) finding the axial center of the Rim and Shell Frames and, 2) adjusting tension between the drive wheel and rim.

My experience has shown that rushing to build is the primary cause of poor design, waste of material, and the failure to make final delivery. So be patient and allow the design, build and assembly description processes the time and respect they deserve.

The Question of Why

As of this writing, an excellent Shell pasting machine is available to the public; the machine is marketed as the WASP. The WASP is made and sold by Jim Widmann, of CT Pyro in Connecticut. These machines are a marvelous creation and the general consensus of pyro-enthusiasts is the WASP does an outstanding job pasting ball shells.


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So why create a hand powered machine when I could save up for several months and buy a WASP? Please believe me, I asked this question several times when, on occasion, I considered scraping the project. The reason is I like to make and use things that are not dependent on electronics and micro-circuitry. Creations that reduce my labor, but are within my ability to fix when the time arrives, have strong appeal to me. I derive great satisfaction from designing and building a tool that: 1) adequately performs a labor saving function, 2) is as concise in form as my mind can make it and 3) is within my ability to repair without dependence on outside sources. The most difficult thing to replace on this machine is the gearing. Should one of these gears go south I would probably break down and buy a replacement. I am a hobby machinist and have the necessary equipment to cut gears but it is not something I have ever done. In all honesty, I would likely purchase a new gear. (I did buy an extra mitre gear just in case.)

Despite my strong desire to bring this idea to reality, with all of the patient detailed planning, there remained a nagging risk in the back of my mind “What if I spend the money and the damn thing doesn’t work or produces substandard ball shells.”

To that nagging bit of doubt, the words of Teddy Roosevelt provided encouragement:

“Far better is it to dare mighty things, to win glorious triumphs, even though checkered by failure... than to rank with those poor spirits who neither enjoy nor suffer much, because they live in a gray twilight that knows not victory nor defeat.”

The Quest – Satisfaction Criteria

Having managed projects over the years, I am familiar with two things that are the bane of successful project completion: 1) lack of a Vision statement and 2) scope creep as the design progresses.

The following was my Vision Statement:

A hand powered machine that will be portable and paste ball shells with consistence and improve the effect of containment in aerials.

This Vision Statement decomposed into four criteria for success. The machine must be:

1) capable of easy disassembly into four components. 2) able to fit inside a 36” x 36” x 12” corrugated box when disassembled. 3) functional when reassembled without the need to excessively tweak and fuss over it. (I define

“excessive” as anything more than half an hour, including assembly) 4) capable of producing up to 8” pasted shells that were uniform and tight.

That’s not much to ask for, is it?

As I worked through the design and wild ideas inserted themselves, I checked them against the 4 criteria above and usually discarded them. One such idea was a numbered rotation counter. I decided a rotation


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indicator would be just as useful and could be accomplished by placing indication marks on both the Ball Shell drive shaft and the drive platform; a concise and effective alternative.

I am absolutely certain the design I used for this machine could be more concise, but it was the best my mind could produce. If this sort of thing interests you, then I challenge you to do better and, if you succeed, I will be the first to congratulate you. I revel at man’s ingenuity and like to learn from others.

The Approach

At first, I scribbled a few concept diagrams to get a feel of the project’s plausibility. Once I felt more than 50% certain I could do it, I established the four criteria above for the final product. Having these criteria established up front significantly influenced the design as it began to mature. From this point, it took several weeks to translate the initial image in my mind onto paper, in the form of 2D and 3/4 view drawings. The original image, of the delivered product, evolved into its final form approximately 14 days after I drew my first concept diagram. I spent the next 5 weeks describing the build and assembly process then finally building the machine. See Attachment 1 – Concept Drawings to get a feeling of how the design evolved over the 14 days. Page 1, of Attachment 1, shows a scrapped design and an early version of what would be the final design. Pages 2 and 3 show the final design and break outs of several subassemblies.

As the drawings progressed toward completion I started noting the hardware needed on the drawings. This prompted me to transfer these hardware items into a spreadsheet that identified the source, the cost and the status of order and receipt. See Attachment 2 – Bill of Materials and Calculation Worksheet.

As an aside:

The machine, as I designed and provisioned it, was not light weight. The frames and drive platform are approximately 75 lbs. Add 15 lbs. for a stand and the combined weight is 90 lbs. Attachment 2 shows the total weight of the machine. I wanted this machine to be portable and 90lbs is very near the point of unacceptability. I will build a fitted box from plywood, with wheels, for the storing and moving of this machine. I’m getting older so I may need help, at some point, getting into the back of my truck but it is portable. If a fully mechanized, light weight, shell wrapping solution is your goal; don’t venture down this road; go with the WASP.

Next, I made a decision regarding the material I would use for the frame(s).

I am not a structural engineer so, after completing the build and assembly, it became evident I over engineered the machine. The use of cast iron pillow and flange bearings is one example of over engineering; I could have used pressed steel (adequate for the job and lighter).

I chose 1x6 red oak lumber for the Rim Frame. Both 3/4”x1.5” and 1/2” x 1.5” rectangular steel tubing was used for the Shell Frame. Wood was chosen for the Rim Frame for aesthetics; I like the look of wood and steel. While wood expansion is a concern, I limited this expansion to the Rim Frame. I believe by


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containing the deleterious impact of wood expansion to this area the effect will be manageable. I could not tolerate expansion in the Shell Frame so it is made of steel. Maintaining proper meshing of the gears would become tedious for the entire machine so I limited that tedium to the interface between the Drive Platform and Rim Frame.

Notes regarding the build and assembly process began creeping into my drawings; see Attachment 1, page 2, so, in similar fashion to capturing the hardware required, I decided it was time to divert my attention to detailing build and assembly instructions. When two activities begin encroaching into one time slot, I take the cooperative intrusion seriously. I believe it is a helpful hint from the great Designer Himself. After considering the progress of the drawings, see Attachment 1 – Pages 2 and 3, I believed they were mature enough to support build and assembly descriptions.

Detailing the build and assembly instructions requires thinking about the priority of assembly as well as prioritizing the subassemblies in relation to the primary function of the machine. The four subassemblies of the Shell Pasting Machine are the Rim Frame, the Shell Frame, the Drive Assembly and the Stand. I knocked one of the subassemblies, the Stand assembly, to last in priority. That left me with three subassemblies. When considering the order of priority between the Frame and Drive subassemblies, it became apparent that everything depended on the axial alignment of the Rim Frame, Shell Frame and Drive subassembly. The alignment of the Shell Frame and the Drive subassembly to the horizontal axis of the Rim Frame is critical to the proper function of the machine. If these three axis’ are not very closely aligned, just outside the Rim Frame, the Shell Frame mitre gears will disengage from, or bind on, the drive mitre gears. It also became apparent that the parts of the Shell Frame drive mechanism and Drive subassembly that met at the Rim Frame horizontal axis would need to be assembled concurrently.

After considering the above, I established the following priority of subassembly build and assembly instructions:

1. Rim frame 2. Shell frame 3. Drive Platform 4. Attaching the Drive subassembly to the Rim Frame and aligning the gears 5. Building the tape dispenser and water reservoir, 6. Attaching the tape dispenser and water reservoir to the rim 7. Connecting the drive wheel to the drive pulley

Additionally, I felt it would be useful to others, who might venture down this path, if I:

8. Described shell pasting preparation 9. Described the method of pasting that produces round shells and how to determine when the shell has

reached pasting completion


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Build and Assembly Instructions

Rim Frame, Shell Frame, Leg Stand, Drive and Support Subassemblies

I decided to use 35”x35”x11” as the following maximum outside dimensions of the disassembled and packaged machine. The following build and assembly instructions (for Rim Frame, Shell Frame and Drive Platform) are listed in priority of execution that I built this paster.

Important: I used several custom pieces of material for this build process. One was a 1/2”x12” piece of round stock having 2” on one end of the stock wrapped with aluminum tape to a diameter of 5/8”. This item, or a suitable alternative (perhaps doweling), should be obtained before proceeding beyond the Shell Frame assembly. To understand how this item was used, start with the last bullet for the Drive Platform build and read the Drive Platform Installation assembly steps. The second custom item was a 3/4” x 2” wood dowel with a 1/2”x 1” hole drilled in the end and fitted with a 1/2” x 2-1/2” piece of bar stock. This was used to align bearing mounts with the 3/4" holes drilled in the Shell Frame support arms so the bolt holes could be marked and drilled. The last piece of custom material was a set of templates to ascertain where the Shell Frame would meet the Rim Frame so that the tape would cover all but 1” of the shell (refer to Attachment 3). This 1” gap would be at the axis of the shell where the shell is being held in the Shell Frame by 1/2" rods. This template was also instrumental in establishing the length of the Shell Frame main arm.

Paster Assembly Build Order 1. Rim Frame

• cut three 1x6x30” and two 1x6x33.5” boards • Use 4-1/8” hole saw to cut end plugs from 1x4 • Enlarge pilot holes to 1/2" • Plug one end of ABS with end plug • Run silicon sealant around inside corner of end plug (let dry) • Place 1/2" x 12” rod into center of bottom plug • Create Drive Wheel by pouring PMC-770 rubber into a 4” ABS pipe waxed on the inside to depth

of 3-1/2” o If I were to do this again I would use 4” ID aluminum round tube because the ABS was no

perfectly round and I had to lathe the wheel down. o It should also be noted that the final drive wheel diameter was 3.5” not 4”

• Put other end plug over 1/2" rod o This will center the rod in the rubber

• Let drive wheel set over night • Pull the drive wheel from the pipe 24 hours later • assemble rim frame using 90 deg braces • fit lift platform guides on lower braces • drill 29/64” holes (soft wood) or 15/32” holes (hard wood), in lift platform for 5/16-18 inserts

then glue and drive in the inserts • mark center line on top, lift platform and bottom horizontal sides of rim frame


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o use square to scribe this centerline across width of top rim frame board • scribe center line on top rim frame board down full length of the board • drill four 1/2” holes in top of rim frame along lengthwise center line

o first holes are drilled 5” from intersection of scribed centerlines o second holes are drilled 10” from intersection of scribed centerlines

• scribe parallel lines connecting the outside diameter for each of the two holes on either side of centerline

• use jigsaw to cut along the scribed lines connecting the holes drilled above o the result will be elongated 1/2”x5” slots on either side of the centerline intersection

• attach idler wheels to inside top of rim frame o separate wheel axis center, 7.5” on either side of center previously marked rim frame

centerline • attach drive wheel mount and drive wheel to lift platform

o align drive wheel center axis to previously marked rim frame centerline • insert rim into rim frame and screw lift plate up until drive wheel touches rim and secures the rim

in place o check for free rotation of the rim on the drive wheel and idler wheels, adjust as necessary

• attach rim guide to lift platform next to the drive wheel, using 90 degree brace o the rim guide was made from left over 1x6 oak stock, a rectangular notch was cut in the

top of the stock o the rim passed through the notch and plastic floor savers where cut to size and inserted

on each side of the notch o a tilted drive wheel will be evidenced by the rim moving to one side of the rim guide

• measure vertical axial center with rim in frame • drill 3/4" hole in drive side of rim frame at vertical axial center determined in previous step • cut a 1/4”x1-1/2”x2-1/2” spacer plate • cut 1/8”x2”x12” brace plate for inside of Rim Frame • cut 1/8”x2”x6” brace plate for outside of Rim Frame • mark center of 1/8”x2”x6” brace plate and drill 3/4" hole • position 1/4” spacer plate on one end of bracing plate, clamp and drill 3/4" hole through both the

spacer and bracing plates at the center of 1/4" spacer plate • counter sink 1/4" spacer plate 1" diameter to 1/8" depth • align the 3/4" holes (with countersink visible), clamp and weld to 1/8” inside bracing plate • attach bracing plates to inside and outside of Rim Frame and draw outline of plates • use router to cut out 1/8” inset for bracing plates, then glue bracing plates to rim frame • Center, then screw and glue a 2”x2”x15” board to the bottom of the Rim Frame (for JawStand)

2. Shell Frame

• cut shell frame main arm (3/4”x1-1/2” flat stock) to 31” • locate and mark center of shell frame main arm on length (31”) and width (1-1/2”) • cut a 1/4”x1-1/2”x2-1/2” spacer plate • locate and mark the center of the spacer plate on the 1.5” side • drill 3/4" hole through spacer and main shell arm at marked center locations • counter sink 1/4" spacer plate 1” diameter to 1/8” depth • align spacer plate and shell frame arm on 3/4” drilled holes (use 3/4” round stock) and clamp


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o spacer to be on outside (drive platform side) of shell arm • measure horizontal distance to center of Rim Frame, this measurement is from the outside of the

Rim Frame • add 2.5" to the measurement taken above and this is the length of the shell frame support arms

o 2.5” additional is for bearing mounting surface • Cut support arms from 3/4”x1-1/2 rectangular tube stock to length established in previous step

(18”) • cut 4ea 2-1/2"x5.5" bearing support plates for pillow block bearings • locate and mark center on one end of support arms 1-1/2” in from end on 1-1/2” face • drill 3/4" hole on center mark from previous step • use 3/4” dowel with 1/2" rod insert to center flange bearing on support arm over 3/4" hole

drilled in previous step • mark center of mounting holes on support arm and drill 3/8” bolt holes • weld top and bottom support arms flush to main shell frame arm (mating 1-1/2” surfaces)

o make certain arms are welded to the side opposite the spacer • weld inner support arms

o leave 4" space between top support and inner support arms o leave 4” space between bottom support and inner support arms

• weld bearing support plates to main Shell Frame arm o center 5.5” plates length on Shell Frame arm and true to 90 deg o position one ~4” from 3/4" hole and the other ~4” from top end

• weld support plates to support arms • place Oilite bushings in rim frame and shell frame

o bushings should be flush with surface • connect the two frames with the 5/8" shoulder bolt • secure Shell Frame using 1/2" clamping knob on 5/8” shoulder bolt • Loosely bolt flange bearings to the Shell Frame arm support bracket • run 1/2” SS round stock through the support arm bearings, aligning the bearings and secure the

flange bearing bolts. • clamp pillow bearings to main shell frame arm support plates • place 1/2” SS round stock through the pillow bearings aligning them and attach one mitre gear to

the end of the round stock nearest the Drive Platform 3. Drive Platform

• Acquire 2ea. 3/16”x8”x8" Drive Platforms • measure 2.5" in from one end of each platform along centerline and drill a 1/2" hole in each • cut 1-1/2”x1-1/2” square stock to 10” length for the Drive Frame to Rim Frame Brace • cut a 1”x 4” relief in one end of the Drive Frame brace for the Shell Frame arm swing radius • measure 8” below lower extent of relief (cut above) and cut a 3/16” x 1/2" notch in the brace for

welding the lower plate • drill 2ea 15/32” holes down center line of Drive Frame Brace • take the bottom platform and put a 1/2"x12" rod though flange bearing and secure with set screw • hang this platform between saw horses • position pillow blocks on platform and run 1/2" rod through pillows with worm in center


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• place 30 tooth worm gear on rod extending through flange bearing • adjust pillow blocks and worm gear so that worm and worm gear mesh properly • mark the center of pillow block and flange bearing mounting holes • remove bearings • drill 3/8” holes into lower platform at center marks • attach flange and pillow bearings to lower platform • run a 1/2” rod through lower flange bearing and extend rod through ½” hole in each platform • set lower platform in the notch cut into the brace • set the upper platform on the top of the brace at the 1”x 4” relief

o make certain the top platform is flush with the relief and does not extend into the opening

• clamp the platforms and tack weld them to the Drive Frame Brace o make certain the platforms are square and centered with the Drive Frame Brace before

tacking • remove the bearings and gears and fully weld the platforms to the brace • enlarge the 1/2" hole in the top platform to 3/4" • lightly attach and align the pillow and flange bearing (including gears) on the bottom platform • rest a flange bearing on the top platform • extend the 1/2" rod from the bottom platform through the 3/4" hole • visually center the rod in the 3/4" hole and firmly secure the flange bearing on the lower platform

and tighten the lower flange bearing set screw on the rod • place the flange resting on the top platform over the 1/2" rod • mark the center of the flange bearing bolt holes • drill 3/8” holes at these center marks • attach flange bearing to underside of top platform

o visually centering 1/2" rod in hole on the centerline of the top platform • slide mitre gear over 1/2" rod • place two pillow bearings on top platform • use clamps to secure Shell Frame arm to Rim Frame • replace shoulder bolt with a piece of 1/2”x12” round stock that has 2” on one end aluminum

taped to 5/8” diameter 4. Drive Platform Installation

• clamp drive platform brace to rim frame • with pillow blocks resting (unsecured) on platform surface, adjust platform and bearings until rod

slides smoothly back and forth through both Rim Frame/Shell Frame bushings and the pillow block bearings

• mark center of each pillow block mounting hole • remove pillow blocks • drill 3/8” holes at each center mark located in previous step • lightly attach pillow bearings to the top platform with 5/16” bolts • drill 15/32” holes into Rim Frame and through 1/8” inside brace using the brace holes in 1-1/2”x1-

1/2 brace as guides • remove Drive platform from Rim Frame


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• glue and drive 5/16-18 thread inserts into the Rim Frame from outside of Rim Frame • After the glue on the threaded inserts and brace has dried loosely attach the Drive Platform to the

Rim Frame using 5/16” bolts through inserts and secure with nuts on inside of Rim Frame • Check and adjust platform and bearings until 5/8” round stock once again passes through easily • Tightly secure the Drive Platform to Rim Frame • Replace the 5/8” round stock with the 5/8” shoulder bolt • Unclamp the Shell Frame and use clamping knob on inside of Rim Frame to pull the two Frames

together, securing the Shell frame in a horizontal position o I had to use 1/16” rubber sheet between the Rim Frame and Shell Frame arms to hold the

Shell Frame securely and restrict rotation • Cut 1/2” SS round stock to length and insert into pillow bearings on top platform • Place a mitre gear on each end of the round stock that is passing through the pillow bearings • Loosen all platform bearing mount bolts so that bearings can be adjusted as required • Adjust the worm gears so that all mesh smoothly • Lightly tighten pillow and flange bearing mounts on lower platform and tighten set screws on

worm and bearings • Adjust 1/2” SS round stock and mitre gears until all gears mesh smoothly then lightly tighten set

screws on bearings and mitre gears on upper platform • Tighten mounting bolts so that bearings do not slide easily

o Finger tight may be sufficient • Adjust Shell Frame rod, bearing and gear positions so the Shell Frame and Drive Frame mitre gears

stay in contact as the Shell Frame is rotated around the 5/8” shoulder bolt o This may require repeated loosening and retightening of the Shell Frame, bearings and

gears as adjustments are being made • Lightly secure the pillow bearings to the support platform with 5/16-18 bolt, washer, lock washer

and nut in each hole. • Recheck the alignment of the shaft assembly, adjust if necessary, then securely tighten the

bearing mounts to the support plates • Repeat this process for the entire Rim Frame assembly, making certain the shafts rotate freely

and the gears are closely meshed • Set the Shell frame horizontal and loosen the bearing set screws holding the upper drive rod and

lower compression shaft and move the shafts until they touch and align with no disjointing where they meet, then lightly retighten the bearing set screws

• Mark the center position of each bearing mount hole then drill 3/8” holes in the support plates and lightly secure the bearings to the support brackets with 5/16” bolts

• Confirm shaft alignment, adjusting as necessary, then firmly secure the bearing mounts to the support plates

• Using a dremel grinder (or equivalent) cut a 1” radius into the ends of the 1/2" shell rotation shafts that touch one another, then cut 8 notches so the end is crowned

o grind the crowns into points • Using an unwrapped shell, move the shafts in equal increments out of the Shell Frame until the

shafts just hold the shell centered in the rim • Loosen the set screws on the lower support arm shaft, retract the shaft until its end is between

the lower Shell Frame support arms.


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• place a thrust bearing over the rod, then a compression spring, another thrust bearing, then a clamping collar and push the rod back through the upper bearing and lightly tighten the bearing set screw to secure the rod

• loosen the bearing set screw and push the tube up until it will just barely hold the 4” shell in position.

• Remove the shell and move the lower shaft toward the upper shaft 1/2” and moderately secure the rod by tightening the bearing set screw

• Move the clamping collar so that it rests on the top of the compression spring and firmly secure the collar to the rod

• Pull the lower shaft out from center and reinsert the shell between the shafts and it should be held firmly in place

o If not, repeat the process above, increasing the extension of the lower rod toward center

5. Tape Dispenser and Water Reservoir • I used Kydex for both the tape holder and reservoir frame/guides, heating and forming the

material to the desired shape (see Attachment 4) • The water reservoir was made from a Rubbermaid Lunch Blox container item number 1806176 • Silicon sealant was used on all bolt holes securing the reservoir to the rim and to the reservoir

frame/guides • The bottom of the Lunch Blox has a rim that lent itself to cutting so the reservoir would center on

the rim • I originally planned to have the tape run down into and through the reservoir but scrapped this in

favor of having the tape run across a sponge projecting through the top of the reservoir. o After the paster was assembled and I did my first trial run it became evident the tape was

barely sticking to the shell so I returned to the original dispenser design that ran the tape through the reservoir.

6. Attaching the Tape Dispenser and Water Reservoir • #8-32 machine screws and nuts were used to attach the dispenser and reservoir to the rim. • The heads of the screws were ground down so the rotation of the rim would not be obstructed by the

idler wheels o There is enough of the head left to grasp with needle nose pliers and tighten the screws

• The guides have curved flaps that point in the direction of rim rotation • The tape holder/dispenser is positioned so tape coming off the bottom of the roll is level or above the

slots in the reservoir frame. 7. Connecting the Drive Wheel to the Drive Pulley

• I chose to use an Accu-Link drive belt to connect the drive pulley and drive wheel. It is more expensive than a fixed drive belt but it allowed flexibility during assembly that a fixed belt would not afford me.


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Reference:

Cost per 30 Roll Ctn Roll OD Roll ID

http://www.papertecinc.com/packingTape.cfm $45.00 5" 1"http://www.industrialtapesupply.com/intertape-con-ld-1in-x-166-yds-water-activated-gummed-tape-light-duty-natural-paper/ $56.00 5.6" - 6.25" 1.25"

1" x 500' Tape Sources


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Concept Drawings Attachment 1 Page 1 of 3


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Concept Drawings

Attachment 1 Page 2 of 3


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Concept Drawings



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Bill of Materials and Calculation Worksheet Attachment 2

Page 1 of 4

Received

1 1/2" Shaft Collar Clamping (Lovejoy (6851443205) Amazon 1 x2 1/2" x 10" V-Belt Pulley (Chicago) Amazon 1 x

3 1/2" x 2" V-Belt Pulley (Chicago) Amazon 2 x4 1/2" Worm (Boston Gear GH1056RH - Steel) Amazon 1 x5 1/2" Thrust Bearing Assembly (6031/4VBF53) Amazon 1 x6 1/2" Worm Gear (Boston Gear GB1051 - Bronze) Amazon 1 x7 1/2" - 13 Fluted Aluminum Clamping Handle (JW Winco) Amazon 2 x

8 1/2" Rubber End Caps Amico (package of 4) Amazon 1 x

9 1/2" Flange Bearing (Dynaroll SSFPB2ST) eBAY 6 x10 1/2" Pillow Block Bearings ((UCP201-08) eBAY 10 x11 5/8" ID x 3/4" OD x 1" L - Oilite Bronze Flange Bushing eBAY 4 x12 ACCU-Link (Size A) 1/2" X 9' Adjustable V Belt eBAY 1Need 4' more13 5/8" (1/2-13) x 2 Shoulder Bolt eBAY 2 x14 24" x 1.5" x 2-1/8" Beach Cruser Bicycle Rim eBAY 1 x20 1/2" Mitre Gear (Martin 12M18SS) eBAY 8 x15 1/2" Thrust Bearing Assembly (SKF-9055) eBAY 1 x

16 5/16'' -18 Threaded Inserts (8 per Pack) - Item # 28811 Rockler 4 x17 Stand - Rockwell Jawstand Home Depot 118 4" x 1-1/8" Fixed Caster with Bearings (Will use mount only) Home Depot 2 x19

21 Crank Handle (8" aluminum) Reid PN CH-8AL :: 1471-1-0429 Reid Supply 1 x22 Compression Spring - SSS-231 (.750 OD X .091 Wire X 20" Length) Reid Supply 1 x23 Compression Spring - S-107 (.813 OD X .086 Wire X 10" Length) Reid Supply 2 x24 Compression Spring - SS-41 (.705 OD X .080 Wire X 10" Length) Reid Supply 2 x

25 A569, A36 Steel, SS Tube and Bar Metals Depot 1

26 4" x 1" Idler Wheel (Blk, 95A, 1/2" Bore, Aluminum Core, Set Screw) (Made in house instead w/PMC770) Sunray Inc 227 4" x 2.5" Drive Wheel (Blk, 60A, 1/2" bore, Steel Core, Set Screw) (Made in house instead w/PMC770) Sunray Inc 1

Drawing ID Description Source Quantity


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Page 2 of 4

Gear Number of Junctions EfficiencySubsystem Efficiency

Total System Efficiency

Mitre 4 95.00% 81.45% 81.45%Worm and Worm Gear 1 90.00% 90.00% 73.31%

Wheel Rotation and Tape Spread CalculationsDrive Ratio

(DR)

Drive ratio of 10 x 2 pulley system 4.75

Circumference Distance per 1/30th

Turn (CD)

Tape Separation

(TS)

1/30 turn circumference distance on 4" (3.5" no tape) Ball Shell 0.40 0.50

1/30 turn circumference distance on 6" (5.5" no tape) Ball Shell 0.58 0.71Rim Circumference

(RC)

Distance around a 20.5" rim 64.39Circumference

Traveled Using 4" Drive Wheel

(CT)

Distance rim travels when driven by a 3.48"" drive wheel using DR 51.92

Working Area Between Ball OD and Rim IDRoom on Either Side of 8" Ball Shell (OD = 8 x .955) 5.68

Room on Either Side of 6" Ball Shell (OD = 6 x .955) 6.635

Room on Either Side of 4" Ball Shell (OD = 4 x .955) 7.59

CD = (D x Pi)/30 TS = (CD/ [CT/RC])

CD = (D x Pi)/30 TS = (CD/ [CT/RC])

Rim OD X Pi 20.5 x 3.1412

System Efficiency Calculations

Notes

D= DiameterDR = Drive RatioCD = Circumference DistanceCT = Circumference TraveledRC = Rim CircumferenceTS = Tape Separation

(Rim ID - Finished Ball Diameter)/2


Using 9.5" as ID of 10" Pulley - R = 9.5/2


Drive Wheel OD X Pi X DR


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Page 3 of 4

Status

Description Utilization Length in Feet Wgt/FtWeight of Piece (lbs)

Total Weight of

Steel Framing

(lbs)Number of

Mounts

Mount Weight

(lbs)

Total Bearing Mount

Weight (lbs)

Total Weight of Frame

(lbs)Shell Frame 32.04 6 33.74

1-1/2 X 3/4 X 11 GA (.120 wall) A513 Steel Structural Rectangle Tube Shell Frame Support Arms 6.00 1.64 9.84

1/2 inch Dia. 304 Stainless Steel Round BarMain Shaft for Worm and 10" Pulley and all Drive Mitred Shafts for Shell Rotation 7.75 0.668 5.18

x 1/4 X 1-1/2 Hot Rolled A-36 Steel Flat Spacer for Shell Frame 0.33 1.7 0.57

3/16 X 2-1/2 Hot Rolled Steel Flat Bearing Support Plates on All Shell Arms 3.33 1.596 5.32Using Tube 3/4 X 1-1/2 Hot Rolled A-36 Steel Flat Main Shell Fram Arm 2.33 3.825 8.93

1-1/2 X 1-1/2 X 11 GA (.120 wall) A513 Steel Structural Square Tube Brace for Drive Platform to Rim Frame 1.00 2.21 2.213/16 X 4 Hot Rolled Steel Flat Support for Shell Frame Support Arms 0.67 2.55 1.70

33.74

Frame Weights Using A569, A36 Steel Flat/Angle, SS Round and Tube, and Cast Iron Bearing Mounts


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Page 4 of 4

Length in Feetor Unit Weight Wgt/Ft

Weight of Piece (lbs)

Total Weight of

Wood Framing

(lbs)Number of

WheelsWheel Weight

Total Weight Wheels and Hardware

Total Weight of

SubassemblyRim Frame 16.47 3.00 6.00 29.10 46.59

x 1 x 6 Red Oak for Rim Frame (3ea 6 foot lengths) 10.33 1.00 10.33x 1 x 6 Red Oak for Lift Platform (1ea 6 foot lengths) 2.50 1.00 2.50x 1" Trim for Platform Guides (1ea - 6 foot or less) 1.33 0.25 0.33x Everbilt - 90 Deg Inside Corner Brace - MFG Part # : 18566 8.00 0.25 2.00

Thumb Screw Cap for 5/16-18 Hex Head Machine Bolt (Reid Supply - Item No: SLK-7) 2.00 0.05 0.10

x 5/16-18 x 1.5" - Nuts and Bolts for Idler and Drive Wheels 6.00 0.10 0.60x 2x2 White Pine for Platform Bracing to Rim Frame (1ea 6 foot) 6 0.55 3.30x Rockwell 33 in. JawStand XP Sawhorse 1.00 18.40 18.40x 2ea - 4" x 1" Idler Wheels Made from PMC770 2.00 2.00 4.00x 1 ea - 4" x 3" Drive Wheel Made from PMC770 1.00 2.00 2.00

4" OD x .125' Wall - Aluminum Tube Drive Wheel Form for PMC770x 5/16-18 Nut Inserts 20 0.10 2.00x 1/4 x 1-1/2 Hot Rolled Flat Spacer for Rim Frame 0.33 1.70 0.57

x 1/8 X 1-1/2 Hot Rolled Steel FlatBracing on Inside of Rim Frame for Bolts Going Through Drive Platform Brace 1.00 0.45 0.45

46.59

Total Weight of

SubassemblyDrive Housing/Shelf 16.13

3/16 X 8 Hot Rolled Steel Flat Top and Bottom Drive Platforms 2.00 3.83 7.661/2 inch Dia. 304 Stainless Steel Round Bar Main Shaft for Worm and 10" Pulley 1.00 0.67 0.67

x 5/16-18 x 2" - Bolts and Nuts for Mounting Bearings 10.00 0.10 1.00x Accu-Link Adjustable Drive Belt 8.00 0.25 2.00x Bearing Mounts - Both Flange and Pillow 4 1.2 4.80

16.13 Less Stand Total Weight78.05 96.45

Paster Total Weight 96.45

The Drive Platform and Rim Frame are Made of Wood and Steel Hardware


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First Test Pastings

Six Inch Shell Calculated Separation: .71” Actual Separation: .6875”

Four Inch Shell


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1/2" OD Rotation Tube

1/4" Time Fuse will go into tube during pasting


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Calculation Reference

Comparison of Gear Efficiencies - Spur, Helical, Bevel, Worm, Hypoid, Cycloid

Comparing efficiencies of different gear types across various reduction ratios will help us to make right gearbox selection for our applications. Please note that these efficiency values are for general guideline and refer manufacturers catalogue for more accurate values.

Gear Efficiency Comparison Table

No Type Normal Ratio Range Efficiency Range 1 Spur 1:1 to 6:1 94-98% 2 Straight Bevel 3:2 to 5:1 93-97% 3 Spiral Bevel 3:2 to 4:1 95-99% 4 Worm 5:1 to 75:1 50-90% 5 Hypoid 10:1 to 200:1 80-95% 6 Helical 3:2 to 10:1 94-98% 7 Cycloid 10:1 to 100:1 75% to 85%

1. Spur Gear Efficiency

Spur gearing is a parallel shaft arrangement, and these gears can achieve much higher efficiencies compared to other gear types. Its efficiency varies from 94% to 98% with lower gear ratios.

2. Straight Bevel Gear Efficiency


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Straight bevel gearing is similar to spur gearing with perpendicular shaft arrangement. Like spur gearing these gears also only can handle lower gear ratios with higher efficiencies (93% to 97%).

3. Spiral Bevel Gear Efficiency

Because of tooth shape and contact spiral bevel having less noise and vibrations compared to straight bevel gears, and thus having better efficiency (95% to 99%).

4. Worm Gear Efficiency

Worm gear efficiency varies significantly when lead angle, friction factor and gear ratio changes.

Worm Gear Efficiency Calculation Use the following gear efficiency equation to calculate efficiency of worm gears.

Where f is the coefficient of friction for worm gears normally ranges from 0.06 to 0.02, p the pitch of the worm thread and r the mean radius of the worm.

5.Hypoid Gear Efficiency

The efficiency of a hypoid gear is around 80-95% and can achieve very high gear ratios up to 200:1.

6. Helical Gear Efficiency

Helical gears can run with very high pitch line velocity and can achieve much higher efficiencies (94%-98%) with maximum gear ratios up to 10:1.

7.Cycloid Gear Efficiency

These gears can work in very high efficiencies at relatively high gear ratios above 30:1 and under normal working conditions cycloid gearing efficiency ranges from 75% to 85%.

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