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Traditional Crossbow - BP Hybrid Tiller

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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Mon Jan 24, 2011 8:23 pm

So far, the tools used were planer,jointer and bandsaw. Here is a shopping list for the next phase.

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1/4" dia. x 1" long glue dowels. 3/16" dia. x 2" steel dowels used for axles but will find other temporary use shortly.

Something to nock them out. A large nail works. 1 1/2" dia. forstner bits for the nut socket. TBII glue. Beer. :lol:
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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Sat Feb 12, 2011 11:26 am

After running one edge through the jointer, a final surface sand on the drum sander. I did not have the drum sander when I made my last batch. They worked just fine out of the planer. This is a new toy so I am taking this opportunity to play with it.

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With the edges that will be the top (table) of the tiller facing down on a flat surface, mark two temporary tooling holes in the excess areas.

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Clamp and drill. I use a number 12 drill bit for the 3/16" alloy (not stainless) dowel pins.

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A little clean-up trimming on the bandsaw and the pinned boards are ready for the next step.

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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Thu Mar 17, 2011 7:48 pm

Wow, did this winter just fly by with this PITA project.

Ok, where were we? Hmmm. Let's look at the roller nut. Alchem sells acetal nut blanks cheap, but they are 1.5" dia. stock.
If you are using the 1.5" Dia. forstner bits to cut the pocket, it might be a tad tight. I just brought in a 3 foot length of Delrin (high grade acetal). Keith is making nuts to a design we came up with that cures all the problems I had following the Alchem design.

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This nut is turned down less than 1.5".

The hole for the 3/16 dia. axle is honed.

The .030" sear plate (metal plate that makes contact with the trigger) is hardened steel (we use two .015 thick pieces because they are so damn hard to drill).
The plates are held in place by two roll pins which can be removed if the plates wear.

The string needs to be centered on the bolt. A groove has been added to help achieve that.

There is a pocket machined into it for the quick reset pin. Without the pin, everytime you re-load the bow, you would do the thumb dance where you spin the nut until it was in a position for the trigger to reset via the return spring.

Bottom line is Keith is making these in small batches and they take some time to make. They will be for sale in the near future.
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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Thu Mar 17, 2011 7:52 pm

Not sure if this is viewable. Tried to make a .jpg of a dimensional drawing. Is there a way to attach a pdf??? :ugeek:

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Re: Traditional Crossbow - BP Hybrid Tiller

Postby Kirkll » Thu Mar 17, 2011 10:49 pm

This is cooler than hell Teagus!!!! :D i don't think there is a way to post a PDF doc on the board here, but you could send that drawing via email to guys interested...

how about kirk@bigfootbows.com for starters. :D :D :D this would be a cool project. i'd like to sign up for a hardware package too if that's possible....i gotta build one of these things to shoot golfers with in the yard. :shock: :shock:
http://www.bigfootbows.com/
kirk@bigfootbows.com


Only archers are fool enough to want to make a composite with natural materials and man made materials, and then bend it repeatedly...
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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Sat Jun 11, 2011 2:37 pm

Ok I'm back.
Excuses:
1. Got my yearly honey-dew project done. I'm good for the summer! Front paver stone entryway. Knees are gone.
2. Yikes I'm now living with someones Grandmother. Chaos on a grand scale. Grandma wars broke out. A girl. Pink bows?
3. Scope job at the VA. Good for five years.
4. Finished the laser Kirk!
All were a pain in the rear (and knees).

Layout 4 interior alignment holes, nut axle hole and trigger axle hole on centerboard. Start with the centerboard pinned to the right side board.
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Drill thru centerboard and 1/4" into right side board with 1 1/2" forstner. This is a "take care" step. The nut is 1" wide. You do not want side to side slop in the pocket.
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Without moving the boards, remove the forstner and load the drill for the axle (3/16 steel dowel). drill thru.
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With the same bit, drill thru the trigger axle hole.
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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Sat Jun 11, 2011 2:51 pm

Drill four interior alignment hole. Drill thru the centerboard and 1/4" into right side board. These are for 1" glue dowels.

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Cutting dowels to 1".

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Assemble left side board, turn over. Drill thru both axle holes so the are a match.

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Reverse the process to drill the left side board.

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This completes the nut pocket step.

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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Sun Jun 12, 2011 1:46 pm

Batch of nuts finally arrived. The machinist woke up on a Friday morning with three spider bites. Saturday - emergency room. Then a bad reaction to what ever they gave him. Infection. Surgery. Talk about excuses for being late.

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Re: Traditional Crossbow - BP Hybrid Tiller

Postby teagus » Thu Jun 16, 2011 5:24 am

Having a couple of blank nose plates cut out. There will be more holes for mounting the stirrup. The two holes shown also serve to mount a front site. Final design will be laser cut and powder coated.

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Re: Traditional Crossbow - BP Hybrid Tiller

Postby Kirkll » Thu Jun 16, 2011 9:33 pm

teagus wrote:Batch of nuts finally arrived. The machinist woke up on a Friday morning with three spider bites. Saturday - emergency room. Then a bad reaction to what ever they gave him. Infection. Surgery. Talk about excuses for being late.

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i've been having serious problems with machinists for 6 months bro..... I'm getting disgusted. after all that trouble i went through getting those taper sleds milled, when i went to order another batch he raised the price 30%. :twisted: :twisted: :twisted: i told him to go pound sand up his ass too! :evil: :evil:

hey i'd really like it if you would send that PDF file to my email addy.... PLEASE.... :D

kirk@bigfootbows.com
http://www.bigfootbows.com/
kirk@bigfootbows.com


Only archers are fool enough to want to make a composite with natural materials and man made materials, and then bend it repeatedly...
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