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Not having a welder is a serious liability when trying to build a bow press. After looking at the pipe clamp press on this forums I decided a better solution would be to mount the same sort of fingers on a trailer jack. This gave me the benefit of having enough travel to completely disassemble a bow and yet it was inexpensive and relatively easy to build. Best of all it required no welding. I did a lot of experimenting with steel fingers using grinder cutting wheels and a bench grinder. I came up with a reasonable solution but I really wanted some adjustable fingers. I finally settled on this design that is made completely out of Aluminum. I prefer aluminum to steel because it can generally be milled using the same power tools you would use in a wood shop. This is nice if you want the average Joe to be able to build one using his existing equipment. The finger design was completely cut out using my chop saw a hack saw and a drill press. The finger adjustment works simply by turning the shaft bolt. When you tighten it the fingers thread closer together and when you loosen it the fingers move farther apart. You can adjust the angle of the fingers independently using the 1/4-20 bolts threaded into the back. I'm going to be posting a bunch more pictures and instructions so anyone who wants to can copy my design and build their own. I know a lot of you will complain that the bow sits on the press rather than dangle from it. Frankly I've used this design for about 5 years now and I see no need to have a bow dangle other than that's the paradigm that was set by the commercial presses. All it does is add complexity to the build and takes up more space. With this compact design it's easy to throw in the car and take it with you for those longer distance hunts. I have built 4 of these now with slight variations and donated them to my local clubs. Enjoy!

Oh here is the original thread you can see how the press has progressed over the last several years
http://www.archerytalk.com/vb/showthread.php?t=1321214&highlight=Welding+50.00
 

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Discussion Starter #2
Here is a list of tools and materials you’ll need.
Chop saw or table saw.
Drill press
Hacksaw
Belt sander if you want smother finishes.
Spray paint can with the color of your Choice if you want it a pretty color…
9/16 drill bit
1/4 drill bit
#9 drill bit - for holes that the 10-24 bolts fit through
#7 drill bit - for holes to be threaded with 10-24 taps usually come with the correct drill bit.
#25 drill bit - for holes to be threaded with 1/4-20
F – drill bit - for holes to be threaded with 5/16-18
5/16 drill bit
5/8” drill bit - for counter sinking the screw holes
3/4 drill bit - with a 1/2” shank so it fits your drill press chuck.
5/16-18 Tap and Die
1/4–20 Tap
10-24 tap
 

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Discussion Starter #3
Here is the materials list

1 - Harbor Freight Square Trailer Jack
4 – 5/15-20 x 3.5” bolts Socket head
8 – 1/4-20 x 1/2” bolts flat Allen head
4 – 1/4-20 x 1” bolts Socket head
4 – 10-24 x 1/2" flat Allen head
10 - Washers for the 5/16” bolts
4” x 4”x 1/2” x 12” long Aluminum L angle
1/2” x 1/2” x 1/8” x 12” long Aluminum L angle
3” Square Aluminum tube with 1/4" wall thickness 12” long
1 3/4” Square tube 1/8” thickness walls 18” long
2- 3/4” x 1” compression spring I think McMaster-Carr #9657K314 will work but the ones I used were ones I bought at Lowes and modified them slightly.
4- 1/2" X 1/4" Bushing with a 5/16” center hole, anything that will keep the sping centered on the 5/16" shaft bolt.

All the metal can be purchased from Online Metals in 1 foot increments.
All the hardware can be purchased from McMaster-Carr.com
 

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Discussion Starter #4
Step 1
Swapping out the crank to the opposite side of the jack so that a clockwise rotation compresses the bow. This is optional but make the operation a lot more intuitive.

1) Remove the screw and grease fitting that hold the plastic end cap in place
2) Using a nail or a punch and a hammer pound the retaining pin out of the gear and crank. Extract the pin from the inside of the jack as it drops out.
3) Leave the gear in place and pull the crank out.
4) Drill a whole with the 9/16 drill bit about 5/8” from the end of the crank
5) Slide the crank back in on the opposite side of the jack and replace the press fit pin through the gear and into the new hole you just drilled.
6) Return the black end cap and grease fitting to the end of the jack.
Now when you crank the handle clockwise it will compress the jack.
 

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Discussion Starter #5
Step 2
Creating the insert that fits into the end of the jack. You can use the foot that comes with the jack by cutting off the base but I found that it fits a little sloppy and isn’t really long enough to handle the longest bows. So I use the 1.75” Square Aluminum tubing.

1) Set your table saw up at a 45 degree angle and chamfer each corner of the insert back about 1/8” This allows it to slide into the jack base.
2) If it fits real tight you may need to remove burs on the inside of the jack with a file.
3) Drill 4 holes 3” apart starting 4.5” on center from the end of the insert.
 

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Discussion Starter #6
Step 3
Building the finger Assembly
3.A Cutting and drilling the fingers.

1) Using your chop saw cut the 4”x 1/2” Aluminum L angle in 4 pieces that are 3/4” wide. If you don’t like the rough finish cut them marginally wider so you can sand or mill the finish smooth.
2) Cut one side of the L angle to 1.75” long.
3) Setup your drill press with a clamp so you can drill all four finger with the F drill bit (the one for 5/16-18 tap) in the exact same place on each finger. By drilling all 4 exactly the same you ensure that the hole is consistently in the same place. Note when drilling metal you get a much cleaner hole and there is a lot less wear and tear on the equipment if you lubricate the bits and parts as you are drilling with cutting fluid or WD40 will also work.
4) Enlarge the hole on 2 of the fingers with the 5/16” drill bit
5) The two fingers that were not enlarged, using the 5/16-18 tap cut threads in the hole at the base of the fingers.
6) Again with a clamp on your drill press set so you can drill a consistent hole using the #24 drill bit (the one that came with the 1/4-20 tap) drill a hole in the foot of each finger centered 5/16” from the end
7) Using the 1/4-20 tap cut threads in each of these holes. Use plenty of cutting fluid or WD40 so avoid breaking the tap.
8) Using the number #7 drill bit drill a hole in the finger centered 1” from the top that you can use to bolt the limb shelf onto.
9) Using the 10/14 tap cut threads into the limb shelf hole.
10) Using the chop saw cut the 1/2” x 1/8” L angle to 3/4” wide pieces
11) Using the #9 drill, drill a hole in the center of one side of each of the limb shelf pieces.
12) Using the 10-24 screws bolt the limb shelf to the fingers.
13) Thread in the 4 -1/4-20 x 1” bolts into the fingers feet
Your fingers are now complete!
 

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Discussion Starter #7
Here are the dimensions for the fingers and the bases...
 

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3.B Making the finger bases and assembling the fingers.
1) Using the chop saw cut a 3” long piece from the 3” square tube.
2) Now turn it sideways and with the shop saw cut the tube so that you have a U channel with 1.25” side wall. You’ll need to cut the other side so it too has a 1.25” side wall. You should now have 2 pieces that are 3”x3”x1.25”
3) Using the 5/16 drill bit drill a hole in the 1.25” wall 2.125” from the end and 5/8” of an inch up from the bottom. This is the hole that the 5/16” bolts\shafts will got through to hold the fingers in place.

4) Using the 1/4” drill bit drill 4 holes in the base so that the finger base can be bolted to the insert and the Jack. Holes can be drilled 1/2" From the end and 1. 25” apart on center
5) Clamp the finger plates in place on the insert and on the jack frame and drill the mounting holes with the #24 Drill bit.
6) The 8 holes you just drilled now need to have threads cut with the 1/4-20 tap
7) Using the 1/4-20 bolts mount the finger bases to both the insert and the Jack.
8) Add a washer to the 5/15”x3.5” bolt and then lace it into the finger base now add the finger with the enlarged hole.
9) Add another washer and both plastic bushings
10) Slide the spring over the plastic bushings and then add another washer.
11) Compress the spring enough to slide the second threaded finger in-between the last washer and the outside finger base wall.
12) Rotate the finger shaft bolt to thread it into the second finger, thread it through until the bolt head is flush with the outside of the finger base. Now add a washer on the far outside of the finger base and thread on the shaft nut.
13) Make sure the finger shaft bolt rotates freely and then with a hammer mushroom the end of the bolt to prevent the nut from coming back off. A little epoxy wouldn’t hurt either.
14) Now by rotating the shaft bolt you can adjust the width of the fingers.
 

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Discussion Starter #9
Lastly you need to cut the Pin that holds the insert in place so that it doesn't stick too far out of the bottom.


Also here are what the old fingers looked like, They have now been replaced with the wiz bang super duper adjustable ones.
 

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Very nicely done there bOw bender. Great job on explanation and pics. You do contribute alot to AT, and i for 1 appreciate it.
 

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Awesome, I want one. although I would like something that secures the bow from wanting to shoot up. would this do beyond parallel? Ex, insanity, invasion etc..
 

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Spectacular press build and instructional thread. Once again, bringing your "A" game to the DIY Forum. :thumbs_up
 

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nicely done. by far the best looking no welding press ive seen on here
 

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Discussion Starter #16
Awesome, I want one. although I would like something that secures the bow from wanting to shoot up. would this do beyond parallel? Ex, insanity, invasion etc..
This is an excellent question and to be honest I don't know. I don't own one of the beyond parallel bows to test it with. My thought is that you could wrap a strap around the jack and the bow to keep a beyond parallel bow from shooting up and that would work I simply cannot say for sure. I have pressed one of the kids PSE bows with it I made a curved finger cover that pressed against the limbs and that seemed to work well. But that was for the PSE that has the real curled limbs. the Hoyt is a different story. How do the commercial presses deal with it or do they use a different design?
 

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Great ideas.
Have you pressed Bear bows? What is the highest bow poundage that you have pressed? I have read that 70 lbs is a usuall bow weight and 80lbs is rare.

Anyway, great ideas!
 

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Discussion Starter #18
the heaviest bow I shoot is 63# and it did that with out much grunting. I'm sure it could do an 80# bow with no problem.
 

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Discussion Starter #19
how far does the press [HF jack] move with 10 full turns of the crank?
Once upon a time I calculated this out by counting the cranks over the full travel distance and then I measured the full distance. with a little math I was able to calculate that it takes 8.44 cranks per 1 inch of travel that's .1185 of an inch per crank.
so 10 cranks would be 1.185 inches.
:icon_1_lol:
 

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Super great post. Thanks so much. Definitely tagging this for future. Very nice design and well detailed and documented.
 
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