Bulding my Bamboo Backed Ipe and Questions...

[vanillabear?]

[xstatic1971]

Yeah, I might just sand away...  Definitely won't let him touch it unless I am feeling very confident. Very good honest feedback and I really appreciate it.

Thanks!

Craig

[Osagetree]

The crack on the belly is a compression fracture created by the hinge or by the bamboo over powering the IPE...

I'd say this one is toast. Good news is, this lesson will not be soon forgotten! Right?

You learn more from your mistakes than anything else!

[xstatic1971]

Agreed Osagetree....  Yes, bowyering is FULL of lessons.  Already have a new one in the oven and one for my son is ready for glue-up tomorrow.  I did one thing very differently this time.  I trimmed the bamboo a bit thinner this time and I also pre-tillered it, just checking to make sure it bent uniformly before glueing.  I think that was my issue last time as I just generally checked the thickness, but didn't check the actual bend and since my Ipe was pretty flat and even I think it was probably the bamboo causing the issue...

Hopefully I am right!  

Thanks again!

Craig

[Mark Smeltzer]

Razor Back had it just right for early tiller

[xstatic1971]

Yup.  I am on round two and it is looking better already... except......  Looks like the reflex deflex is off about a quarter inch.  :(   Ugh.  Should have measured it.  I guess one of my blocks was at a different angle.  

Best way to adjust this?  Re-clamp and put back in hotbox?  Use a heat gun?  

Thanks!

Craig

[NTD]

none of the above, you can fix it some during tiller, it's just a stiffer limb, that's all.  probably end up using that one as the bottom limb.

[NTD]

What I mean is that the limb with more reflex will be stiffer, you can compensate in tillering and use that one (the limb with more reflex) as the bottom limb.  Should be fine.

[xstatic1971]

Thanks NTD!  That is good news indeed.  Will save me some headaches for sure...

 

Craig

[NTD]

No problem, I'm definitely no expert so if someone else chimes in consider their advice as well.

For some pointers on tiller...
I try to imagine the fades to midlimb(to where it starts to reflex) as a mini bow.  Block out the outer limbs in your mind.  Get that mini bow bending smooth just like any other bow.  Once you have that inner bow bending nicely you can start to work on the outer limbs, scraping or sanding them slowly until they just break over (open up)which will result in that mini bow just having long stiff tips.  Don't know if that'll help you but it's what helped me tiller these beasts.  Also once you notice any hinges or stiff spots on that mini bow, DO NOT PULL IT FURTHER.  You'll want to get it bending nice again before increasing your draw.  Good luck and have fun.  I destroyed 3 R/D's before getting a decent one and then mediocred 2 more before I had a decent one.  And PatB says I'm a quick learner LOL  :D

[mullet]

I'm jumping in this late, but my take on this is you took too much wood off too quickly, which is probably obvios to you now.
  You have to tiller these bows, especially with Ipe, slowly. It doesn't take very much wood removal to make this style bow break over the top. One problem I noticed is trying to get an eliptical tiller. This type bow gets more performance out of a "D" shape. Work the tiller till the last 1/3ird of the limb starts to break over at full draw.

[mullet]

Oh, yea, get rid of that Tiller stick and make yourself a pulley set up. It puts a lot less stress on the bow and you can exercise the limb between scraping wood, and this is important.

[xstatic1971]

@NTD.  That is a great point on the tiller and really helps me see how it should look.  I will be hopefully finishing up the tiller on my "Part 2" tomorrow, so hopefully can pull it off.

@Mullet.  Got a new pully today and installed it on a fence post, so ready to go and tiller with it.  The last pully I tried was one I found in my toolbox.  I only had the guts to tell my wife today that when I tried to tiller the last bow with it, the pully blew off which in turn launched the bow into the air which came down and hit me in the back even though I was about 7 feet away.  

Moral of the story.  Make sure your pully isn't defective!

 

[xstatic1971]

OK, round 2.  I have 2 bows in the works, one for me and one for my son.  This is my sons bow.  Right now it is about 36 lbs at 23" (his draw length) and I need to get it down to around 30 lbs.

I am not sure if I need to make the limb bend some more to the left of the fade or work on the mid-limb on the right limb to make the area closer to the fades bend less?

(FYI.  I have been using my tillering tree for this.  Just put it on the stick quickly for the pic.)    

 


Sorry this pic is tilted a little.  I took it quickly so I wouldn't leave it on the stick long.

 

Thanks!!

Craig

[NTD]

Much better this time.  However, on your next one I would work more of the midlimb.  

Also I try not to draw my bow past the desired weight.  You don't want to work "down" to 30# you want to work "Up" to 23" while never going over 30#

As far as the right limb probably different opinions on that one.  I would work the midlimb to take the stress off that hinge.  If you end up under weight I wouldn't have a problem piking that bow a bit to get you back to weight.

[mullet]

Like Nate said, better. You need to leave the area near the fades alone. You almost hinged it there again. On the next one remove wood from just in front of the curve and after the fade.Get all of this to start folding over in a straight line, then remove a little wood from the fades till you get close to your target draw length. If it's still too much weight then start removing wood very slowly from the sides. You have to remove the wood from the sides evenly or your limbs will twist or get out of aline.

[NTD]

Listen to Eddie :-)he's a wise one, and he builds rocket launchers!!

[xstatic1971]

Woo Hoo!  Got my sons bow finished!!!        Whew!

This bow was made just for him and tailored to his draw weight and length rather than being a bow I was going to make for me, messed up and then turned it into a kid's bow    

It is 60" nock to nock and 25 lbs at 23"

It is Bamboo backed Ipe.  The riser is Zebrawood, Yellowheart and Bocote.  The Tips are Zebrawood and Yellowheart.

Thanks to everyone who has helped me with this!!

Now I need to make myself one!

 

 

 

[xstatic1971]

Rest of the pics...

 

 

 

[NTD]

Not bad at all.  Tillering these guys can be tough but you made some leaps and bounds since the first post :-)  You definitely have a talent for finish work.  It's good to see a kid with a bow.