new bowyer, could use some tiller advice

[ian]

Hi all,

long time reader here.  I attempted making some bows in high school with mixed results.  Its 5 years later now and I want to get back into the bow making game. Could I bother you all for some tiller advice? bow is red oak. about 70".  Will be for target shooting so aiming for a lower weight, ~35-40# @ 28". Currently pulling #34 @ about 18".  Any advice would be much appreciated! I feel like I need to be bending more towards the tips. I hope the photo works.

thank you all for the help,
Ian

[JW_Halverson]

Looks good, but the tips are a little stiff maybe.  Try taking wood off the outer half of each limb. 

When tillering a bend-thru-the-handle bow, you can post your pic on your screen and use a cd or any round object to compare with the tiller.  Just match them up and it will show you where the stiffness is in the limbs.

[Slackbunny]

Looks like you are on the right track. What weight is it pulling at that distance?

[ian]

Wow!! thanks for the tip and such a fast replies  .  Also, its drawing at about 15" not 18" in this photo. My mistake.

@ Slackbunny its at ~34# right now

[bushboy]

Maybe get you middle and outer limbs moving a lot more .

[Thesquirrelslinger]

Here is a tip- When you tiller, pick the weight, then never draw it past that- Lets say you want a 35 pounder. Pull it untill it equels 35, say at 18.5 or so. Then remove some more wood. Maybe it will now draw 35 at 20. THen remove some more wood. Maybe it finally draws 35@27". Now work on the tiller.
THis method prevents overdrawing the bow- It may be the width of a 35 pounder, but it draws 89 pounds, so it will take the set of the 89 pounder at that width.
One techique I use for tillering makes hinges and flat spots really obvious. run a flat, stiff object about 10 inches long or so on the inside of the limbs. If the space between it and the limb looks too rounded, then it is a hinge. if it looks to flat, remove some wood.
-Squirrel
Here is a diagram of the "block" technique- I even labeled it:)

[Pat B]

Have you braced the bow yet or is that a long string? If it is a long string it is time to brace the bow.
  Your bend looks good. A lit stiff mid to outter limb. Leave the middle 1/3 along, at least for now.

[ian]

Okie Dokie, pulling a little further now and bending a little more in the outer limbs.  What do you all think? From here, should I keep working the outer limbs or start doing more wood removal from the entire limbs?

@ Pat B: its braced at about 2" right now
@ Squirrel: Thanks for the diagram and tip!

Thanks again for all help!

[DarkSoul]

Looking good there
Now is the time for a full braceheight of one mist melee or about 5½". Only then you can truly judge the tiller and the drawweight. But I'm guessing the tiller is REALLY close! But just too heavy. You will probably need to scrape both limbs along the entire limb to lower the drawweight. But brace it higher first.

[Josh B]

I agree with Darksoul, time for full brace.  I must say, I'm quite impressed with your tiller so far!   A technique I use when I have the bend right and just need to lower draw weight is to make pencil lines on the side.  One Mark at center  and then two more marks on the side of each limb that divide the limbs in thirds.  I will then take three full length scrapes from the center to the tips on both limbs.  Then take three scrapes along the outer two thirds of each limb.  Then three scrapes on the outer third of each limb.  It's not a fool proof technique, you will still have to do some corrections along the way, but it will help maintain the bend you already have going to some extent.  Much better than scraping randomly and trying to correct hinges as you go.  I hope that helps.   Josh

[ian]

Ok, Ill work on getting the brace height up then.  I made a dacron flemish string for the bow.  It is about 2.5" shorter then the bow but when I string the bow I am only at 2" brace height.  Is my dacron string really stretchy or does that seem normal? If I twist the string shorter I feel like I am killing myself to get the bow braced and strainning the bow unnecessarily. Maybe its in my head and due to inexperience.

@Gun Doc: thanks for sharring your technique, ill make sure to give it a try once I resume tillering

Ian

[bushboy]

In my experience if you struggle to brace it,it's to heavy!broke a number that way.

[Slackbunny]

Your string could do with being an inch or two shorter. You could try twisting it a bit more, but that won't gain you more than about 3/8 of an inch.

[bushboy]

Just to make sure your not making the mistake I made when first starting out.I thought I had to bend the bow enough to pass the loop over the top knock instead starting with the string on the bow and sliding it up to the knocking point.just in case,but maybe your not as daft as me!lol!

[ian]

Ok, Finally done with the work week and ready to get back to bow making.  Thanks for all the advice so far everyone.  I constructed a srtinging device and now have it braced at 6" from the belly.  Pulling over 20" now and getting close to 28". Trying to be super careful at this point. I think I have been looking at it too long and could use some fresh eyes. The pictures are from each side of the bow.  The tillering stick seems tilted in the second photo, making the left limb seem weaker to me, but not so much in the first photo.



tillering thoughts: Im thinking maybe a little more bend in the tips and maybe take away some wood 15 or 20" down from the handle on the right limb.