# Linear Bow Press Build Thread



## DSLeach (Feb 9, 2011)

I posted in the general section that I was going to build a linear press for myself. I'll try to take enough photos to do a decent build thread here. 

Here are the parts and materials I'm starting with. All the parts came from McMaster-Carr except for the aluminum stock. I still have to get a few basic 1/2"-13 hex nuts at Lowes.


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## DSLeach (Feb 9, 2011)

I'm using 1.75" and 1.5" nestable tubing and a 1/2"-13 threaded rod for the frame and drive. Because there is essentially no radial loading on the rod and the primary force is parallel to the rod, I am going to fabricate a basic aluminum bearing block with an iron-bronze bushing for the radial load and a thrust bearing on each side of the bearing block. 

Below are some pics of the aluminum bearing block. Note I machined a shoulder around the front edge of the bearing block to transfer the thrust load from the threaded rod to the 1.75" main tube.






























In order to allow replacement of the bronze bearing, I did not use a press fit in the aluminum block. I drilled/tapped for a set screw.









More to come.


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## dw'struth (Mar 14, 2008)

Very nice! Show us the rest of it......I just hope the travel speed of the "13" thread rod will satisfy you. I am sure it will be fine, just maybe a little slow if you used it for a draw board or something. Keep us posted.


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## rand_98201 (Sep 24, 2008)

this looks like a cool build


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## lucasm (Jun 24, 2008)

Very nince can't wait to see more like to see other ideas on how to build


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## DSLeach (Feb 9, 2011)

Thanks guys. I'll probably have some more pics up tomorrow or Sunday with descriptions. I did look at using an Acme style threaded rod but there were just too many advantages of using a standard 1/2"-13 tpi rod and coupling nut (availability, costs, handle attachment, etc.). I'm planning to fabricate a custom handle that I can use a drill motor with when I want to make large movements.


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## DSLeach (Feb 9, 2011)

Not a lot of progress. Cut and trimmed all the square channel to length and machined the coupling nut bracket.


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## DSLeach (Feb 9, 2011)

Got side tracked on the press project. Too much regular work and visiting relatives. Today I installed the bearing block in the end of the large channel. I drilled and tapped the channel and block for 10-32 cap screws. Given I have a shear lip all the way around the bearing block, the 10-32 screws are really just to hold the bearing cap in the channel.
























I was going to install the coupling nut in the small channel but I figured out I don't quite have enough amperage output on my welder to do it justice. My welder is wired now for 110 v 20 amp input and that's not enough to give me more than about 60 amps output. I'm going to Lowes to get a breaker and wire to install a 220v 40A circuit. I'll rewire my welder for 220v inupt. That should give me up to 120 amps output which should be sufficient. More to come.


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## Cheese1 (Sep 6, 2009)

A good 110v should weld that fine I would think ? It looks thick but I would say it would work from past experiences. 220V would penatrate much better anyway. The press looks real nice. :thumbs_up


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## DSLeach (Feb 9, 2011)

This morning I installed a 220v 30A circuit and rewired my welder for 220v input. Works much better and I can use 1/8" rod on the highest output setting 120A. 

I finished the drawing for my press fingers. Attached below. No dimensions as it is to scale on my paper. I'm just going to copy it, cut it out and transfer it to the 1/2" aluminum plate stock to cut it on my bandsaw. I just looked at some other press finger drawings and photos to come up with my version of fingers.


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## DSLeach (Feb 9, 2011)

I also installed the coupling nut in the end of the small channel this morning.

I took the small square channel and milled a slot about an inch back from the edge to be able to weld the coupling nut in place. I used this approach because I wanted to counter sink the coupling nut about 1/2" below the channel end and I didn't want to try welding in the recess. I'm make no claims about being a welder but I was able to get it done. No snickering at my welds.

Also below are pics of using the threaded rod to pull the coupling nut inside the channel. I used a slight interference fit for the coupling nut inside the small channel to make sure the centerline of the coupling nut remained parallel with the centerline of the channel. This will prevent any binding of the small channel inside the large channel after all is assembled.


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## codykrr (Feb 6, 2011)

Such nice work!!! precision, precision! I love it! now hurry up and finish it! haha


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## irydhard (May 13, 2012)

Nice build lets see some more


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## Cheese1 (Sep 6, 2009)

He's cutting the fingers now. Shhhhhhh, be patient . :happy1:


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## letsgobowhuntin (Aug 4, 2009)

Looks like your using a stick welder. I was thinking about filling the small pinholes with jb weld to get a good finish on the one i am making.


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## milsy (Jun 9, 2010)

Tag for later....... Great thread :thumbs_up


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## BrownDog2 (Feb 26, 2009)

Looks good.


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## DSLeach (Feb 9, 2011)

Haven't been able to work on the press lately or much of anything else. My father passed away a couple weeks ago so that has been the priority for a while. 

I was able to spend a little time today on the press and fabricated the press fingers. I cut the fingers on my bandsaw out of 1/2" aluminum plate. Then I machined the bases uniform and square. I drilled the base for the 1/2" rod and drilled and tapped the base for the thumbscrew to adjust the angle of the fingers. I still need to knock off the edges and machine a small recess in the base for a spring in the front.


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## hoghntr (May 5, 2009)

sorry to hear of your loss. 

your work is amazing sure wish i had that kind of quipment available to me.. i need to build one that requires less tools.

excellent now make one for me when you are finished.


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## PGHRam (Sep 15, 2010)

DSLeach said:


> Got side tracked on the press project. Too much regular work and visiting relatives. Today I installed the bearing block in the end of the large channel. I drilled and tapped the channel and block for 10-32 cap screws. Given I have a shear lip all the way around the bearing block, the 10-32 screws are really just to hold the bearing cap in the channel.
> 
> View attachment 1437596
> 
> ...


I agree with Cheese1. You should have been fine with 110v. I have a 110v mig welder and I built an auto rotisserie for my GTO with it. No problems at all. I plan on doing a bow press soon.


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## PGHRam (Sep 15, 2010)

Sorry to hear about you father


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## RatherBArchery (Oct 31, 2006)

Sorry to hear about your loss as well!! I can not even imagine that happening and dread the day I have to deal with that!! Thoughts are with you for sure.
On the press build, very nice!!!


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## fishuntbike (Nov 28, 2007)

sorry to hear about your dad, hope things flow smoothly. Regarding your press fingers.. the original LC finger is not flat at the bottom. It has a little curvature to allow easy movement of the fingers against the spring steel when using the set screw at the back....overall awesome built...keep it coming I want to see the final product. Goodluck


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## Cheese1 (Sep 6, 2009)

These fingers came out very nice, very well done. :thumbs_up


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## DSLeach (Feb 9, 2011)

fishuntbike said:


> sorry to hear about your dad, hope things flow smoothly. Regarding your press fingers.. the original LC finger is not flat at the bottom. It has a little curvature to allow easy movement of the fingers against the spring steel when using the set screw at the back....overall awesome built...keep it coming I want to see the final product. Goodluck


I was planning on using a recessed coil spring at the front of the press finger base and just leaving a gap between the flat bottom of the finger and the press frame arm. If I don't get enough adjustment with the press finger, using a curve/radius on the bottom would be a good solution. Thanks.


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## DSLeach (Feb 9, 2011)

I worked on the brackets this morning for a little while. Measured, marked and drilled the 1/2" hole. Had a old chucking reamer at exactly 0.5000" which worked out well because the 1/2" drill was a bit undersized. 

Last picture is after sanding and knocking off the edges.












































I still have to drill and tap a 10-32 hold in the top of each bracket to keep the 1/2" rod fixed and I have to find the right size springs to put in the base of the fingers. Then it will be time to start welding the parts together.


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## jrdrees (Jun 12, 2010)

Good workmanship here!


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## Gunner7800 (Jul 11, 2007)

Awesome job on this press. Wish I had the tools to do a build like this. I can't wait to see the finished product.

I would like to make one suggestion from my experience, use 2 mounting blocks for the fingers on either end of the rod. That way you can get the fingers as close together as possble without being incumbered by the single mounting block in the middle. You will also notice more room around the cam, it can be a pretty tight fit between the block and the cam unless your fingers are long.


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## agingcrossbower (Mar 19, 2009)

My forte is WOOD. Watching you do this is truly fun. Your a true artist at what you do. Great thread and sorry to hear about your Dad's passing. Tough times for sure. Thanks for sharing this.


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## DSLeach (Feb 9, 2011)

Gunner7800 said:


> Awesome job on this press. Wish I had the tools to do a build like this. I can't wait to see the finished product.
> 
> I would like to make one suggestion from my experience, use 2 mounting blocks for the fingers on either end of the rod. That way you can get the fingers as close together as possble without being incumbered by the single mounting block in the middle. You will also notice more room around the cam, it can be a pretty tight fit between the block and the cam unless your fingers are long.


That's why I have 4 mounting blocks in the picture. I've been waiting for someone to ask why I have 4 rather than 2. I'm planning to do exactly as as you suggested.


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## Gunner7800 (Jul 11, 2007)

DSLeach said:


> That's why I have 4 mounting blocks in the picture. I've been waiting for someone to ask why I have 4 rather than 2. I'm planning to do exactly as as you suggested.


I was thinking about that but it never really hit home. I'll shut up now and watch, please proceed.


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## b0w_bender (Apr 30, 2006)

DSLeach this is a great post, Let me offer my condolences about your dad and tell you your doing a great job with this project. 

I think it took me a year and a half to get my press to a point where I'm not messing around with it. Take your time but keep the pictures coming I think this is a great thread. I know I'm enjoying it. Most of these press threads don't share the process so this is a nice change. It's great fun to see it come together.


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## DSLeach (Feb 9, 2011)

b0w_bender said:


> DSLeach this is a great post, Let me offer my condolences about your dad and tell you your doing a great job with this project.
> 
> I think it took me a year and a half to get my press to a point where I'm not messing around with it. Take your time but keep the pictures coming I think this is a great thread. I know I'm enjoying it. Most of these press threads don't share the process so this is a nice change. It's great fun to see it come together.


Thanks. I'll probably get some time this weekend to work on it.


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## Cheese1 (Sep 6, 2009)

The 4 blocks on the outside is a great idea. A few years ago I built a press that had the top portion of the fingers stepped over . The upper portion would press on the limbs but the lower sections of the fingers rode out away from the cams. The fingers were stepped over the thickness of another full finger only at the top with round bar and sort of an upside down L to fit over and down the back of the limb. My main fingers were not cut out like the traditional fingers. They were just bars that extended up off the rod, then I stepped it over with a round bar and welded a small "finger" to that. My press fingers worked well and it was always in the prototype stage. It made for so much room around the cams. I loved your idea of the 4 blocks also. Great thinking.


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## DSLeach (Feb 9, 2011)

I found some time to work on the press today. Mostly welding up the parts. I decided to start with the least critical items as my welding skills are pretty rusty. I cut 2 pieces of 1/8" x 2" steel 3.75" long for the feet of the press. I would have used something a little thicker if I had it but I only had 1/8" stock. I drilled the feet with a 5/16" drill which will accomodate 1/4" bolts or lags. 

I then welded the feet on to the bottom of the legs using a big c-clamp to hold everything in place. Then I welded the legs onto the main channel. Here are the pics.


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## DSLeach (Feb 9, 2011)

I also got around to drilling and tapping the brackets for the rod lock screw. Here are the pics.


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## DSLeach (Feb 9, 2011)

Welding the brackets to the arms was a bit tricky because I wanted the brackets to be parallel and square. So, I assembled 2 brackets with a rod and clamped the bracket assembly to the arm. Once I had everything square and parallel, I tacked the brackets to the arm. After tacking I removed the rod and clamps and welded the brackets to the arm.

Here is the pic for everything ready to tack on one of the arms.









This is where my welding skills, or lack of same, began to show. I got the brackets welded on but it's not pretty.


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## DSLeach (Feb 9, 2011)

After I got the brackets welded up, I used the big c-clamp to clamp the arms to the frame and tacked it all together. After removing the c-clamp, I welded all the seams between the arms and the frame channel. Here is a pic of the press assembled but without the drive screw, bearing block or handle.









You can see some of my less than stellar welds in this pic.


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## DSLeach (Feb 9, 2011)

I fabricated the handle today. Used a 12" length of 1" square aluminum stock and a couple 3" pieces of 3/4" round aluminum stock. Relieved the center of the 12" bar and drilled/tapped the center for 1/2" x 13 TPI. Drilled/tapped each end for 1/4" x 20 TPI. Center drilled the 3" rounds with a 1/4" drill. Here are the pics.


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## DSLeach (Feb 9, 2011)

I assembled the bearing block, drive screw, thrust bearings and handle tonight. I used 2 thrust bearings. One in front of the bearing block and one behind the block in case I want to use the press to stretch a string or something. The thrust bearings have a rating of over 1300 lbs so even though they are small, they should handle the force. 

You can see in the pics that you need to sandwich the thrust bearing between two thrust washers. You can also see in the pic that I used a jam nut on the end of the drive rod to secure the handle and two jam nuts behind the bearing block. If the jam nuts don't hold, I'll drill through the nuts and install a cross pin through the drive shaft.


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## DSLeach (Feb 9, 2011)

Just to see if the whole thing will go together and actually worked, I assembled the press with the drive screw and bearing blocks. 

And ................................. *It works*! 

The thrust bearings and the bronze radial bearing make the press really smooth to operate. I can spin the handle and it will coast for several revolutions before the friction of the two square channels stops it. 

I still have to take it apart and clean up the crappy welds, wire brush everything, clean and degrease and finally paint it. That will be next weekends project. 

Here is a pic of the assembled press.


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## BowhunterJT (Jun 4, 2009)

Nice job!


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## bireyn43 (Feb 2, 2011)

Sure is nice precision machine work. I like the idea of using the 4 blocks for mounting of the fingers....GREAT JOB


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## DSLeach (Feb 9, 2011)

Finally got around to painting the press. Looks pretty good even with some of the welds being of the novice variety. So far, I've pressed a BT Soldier, a Fred Bear Odyssey, a Browning Micro Midas 4 and my BT D350. The press works extremely well. The finger adjusting screws make it really easy to get all 4 fingers in even contact with the limbs so the limbs get pressed nice and square. 

Here is a pic of the finished press. Please excuse the messy work bench.


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## hawglarry (Jun 30, 2011)

Very nice work. That's one of the best DIY projects I've seen!


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## Petersen1 (Nov 1, 2012)

Do you by any chance have dimensions on any of this? It looks amazing. I have been researching home built presses for awhile now and this is by far the best one I've seen!!! Thanks for the share!


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## redbone311 (Sep 6, 2010)

mark


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