Red oak board bow "help me as I" build along

[RJonesRCRV]

Just started this red oak board bow last week.  I glued a 10" riser onto a 72" board from Lowes with Tightbond III.  Marked out the general shape and shaved it down to size.  One limb was stiff, and the other was hinging at the mid point.  I got them evened out fairly well, but just want more experienced eyes on it.

This pic has the bow pulled to about 7".

I plan to back it with drywall tape, Fibafuse, which I have due to finishing my basement, hence the studs in my pictures. The tape is fiberglass laid out in a thin random mesh, so I figured it would be less likely to crush the bow back, and when glued up it might be more transparent, as I plan to use an epoxy since Tightbond dries yellowish.  I just want to prevent splintering.

FYI, this is my first bow build.  I would like to give credit to Sam at poorfolkbows.com for the layout and build along and Gawge at traditionalarchery101.com for tons of info.

 

[Homebru]

Hello Robert,
I have very little to contribute. However, I would like to bring to your attention    this thread  in the "How To" forum regarding a red oak board bow.  If you've studied this thread already, my apologies for intruding.  If you haven't, maybe you can find some guidance there.

Hope this helps.
Warmest regards
homebru

[Jomohr84]

I highly recommend making a gizmo if you haven't already, it is an invaluable tillering tool imho. You can see how to make one    here  

Another tool I like to use is a smart phone or tablet with a drawing app, I use Picsart. I draw straight lines and circles on a photo to see how symmetrically things are bending, like this    
Key thing is the photo needs to be as level as possible for this to be effective, luckily you took a good photo!
In the photo you can see the right limb is bending more than the left, and with the gizmo you can see where you need to scrape to get the limbs bending properly

Things are looking pretty good so far, go slow and be patient, and I'm sure some of the "old pros" will chime in and share their invaluable knowledge

I got started with Sam Harper's build along, and he has some great videos on his youtube channel as well, "Sam Harper" is his channel

[mikkekeswick]

Before we can really tell you what tiller shape the limbs should have we need to know what width taper you have used? At a glance tho without that information your right limb is bending too much mid limb.
forget the drywall tape - it's not a good idea. It's not the back it will 'crush' its the belly wood. Think of a wooden bow like a seesaw. Everything works if the two forces are equal. This is what you are trying to achieve with a wooden bow - it's resistance to stretch and compression should be the same. Glass (of anykind) is about 40 times stiffer than wood.......this leads to a massive unbalance of forces in the wood. The stiffer (stronger) back once it has fiberglass tape on will resist stretching way more than the belly has the ability to resist the excess compression that it's now forced onto it.
People use glass tape like this because it holds down splinters (if you choose your wood badly!).....and yes it certainly does hold down splinters but at the expense of ruining the belly wood and getting a ton of set.
Rawhide, silk and linen will also hold down splinters, can be got in nice colours, dyed etc and do not have excessive resistance to stretching. They are all as easy to apply as each other as well.
Don't use the tape!!!!

[Jomohr84]

Yes, I used linen on my first 3 bows, but once I got a little more confident I stopped using a backing and rely on choosing the best wood I can find and tring to tiller properly. I spend almost as much time picking a board as I do making the bow. I would avoid the fiberglass tape as well. If you would like a backing, I would try one of the options mikkekeswick listed.

[ty_in_ND]

In addition to your dimensions, how long is your tillering string now? I've followed Roy's (in_PA) advice about first using a string that just has no slack as your initial tillering string, then once you get the tips bending evenly for 6 inches (that is, when the tips move down 6 inches), move to a sting that gives you a short brace height.  The faster you get off the long string, the better, as the longer string acts differently on the limbs.

Here's a link to another tradgang post that has a TON if useful information. In addition to posting a build-along, bowhunter15 made a video build-along while was getting input from the folks here (he pretty much uses Roy's method of tillering, including Roy's tillering tree setup). Just one caveat: he made a reflex-deflex longbow, so don't look at how his limbs are bending as a template for your bow.

 http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=125;t=012506#000000

Mike listed some great alternatives to a fiberglass tape backing.  One more that should be mentioned is paper.  In particular, brown paper shopping bags makes for a great backing if your goal is to hold down splinters.

Keep up the good work and keep showing us your progress!

[monterey]

Would be helpful if you could show us a pick of the grain orientation on the back of the bow.  You may not need a backing.

I concur on the use of the paper bag backing.  I've glued mine on with TB3 with good results.

[RJonesRCRV]

I have come to a halt for now until I canget a proper tillering string, as I was using 550 cord, which stretches a lot.

I will probably back it with paper, since I have a bunch of barrier paper, and its a natural color.

As far as taper width, the tips are about 9/16" wide, tapering back 15" to 1.5" wid.  The belly taper is tip to riser, so 31" tip to riser.

Here are some pictures of the grain, as best as I could take.  Also there is the most recent tiller, with one limb bending more than the other.

     

[mikkekeswick]

First thing blend your riser piece into your limbs. Very important!
With that width profile you will need to use an elliptical tiller. Eg. As you move from handle to tip you should have little bend off the riser with the bend increasing as you progress along the limb towards the tip.
As for the tiller now the right limb is very close to hinging about a 1/3rd of the way along, the rest of the limb to the tip is barely bending at all. It's also a wee bit stiff out of the fades.
The left limb is better but you have pretty much the same problems as the other.
You should stick on the long string until you get these problems sorted out. Never think about bracing a wood bow until it's long string tiller is dead on perfect.
Another tip for you is to trace the side profile of any bow you work on right at the start. Then as you progress with tillering some set will start to show up. Set is the bows way of telling you where it's over strained....and it never ever lies! I use  this method on every wooden bow I make and once you have it dialled you can't tiller a bow incorrectly no matter the design.
You want no set in the inner limbs, a little mid limb and the rest mid limb to the nocks. Any set at all in the inner limbs has a much larger effect on string tension at brace and therefore performance.

[monterey]

I would back that one!

[RJonesRCRV]

Here it is at 27",  from a 6.5" brace.  I worked on the fades and tillered some more.  The left limb is still a bit stiff by measurements, but pretty even.  I just need to scrape a bit more off.

Probably this weekend I will back it with brown paper and maybe put some sort of overlay or build-up on the tips to protect the nocks.  

I have read about leaving the lower limb slightly stiffer, maybe for split finger shooters.  Is it a big deal?

Any other suggestions or something anyone notices?

 

[Eric Krewson]

On the left limb I would scrape the fade a little about where the 2X4 intersects the limb and in to the handle.

[RJonesRCRV]

Got more tillering done, applied some tip overlays, and backed it with brown paper.

Now that the paper is on and the glue is pretty much dry, there are some wrinkles in the paper, which I expected since I didn't put it in a form.  

My next question is what I should do for a finish.  Would some mink oil be ok just to give it some color, followed by some wipe on poly, once the oil is soaked in and dry?  Or should I just stick with the poly?

As for the tip overlays, I applied some epoxy, laid some green cotton cloth over it, smoothed it out with more epoxy, and covered it with plastic.  I used some 550 cord to pull the cloth into the nocks.  Its not the prettiest in the world, but it seems to have done the trick. Once I get some sanding done, I'll take some pictures and post them, along with the paper backing.

I'm not too worried about great performance or looks, since this is my first actual bow I have made.  I just want something functional that will last for a while, just to get the feel for the work.

[Eric Krewson]

I use mink oil as a patch lube in my flintlocks, don't think it has any bow making applications.

Buy so wood stain if you want color, leather dye also works well.

After staining I would stick to poly or some other finish.

[RJonesRCRV]

 
 
 
 

There is still some sanding to do, and I need to extend the sight window upwards, followed by some wipe on poly, but I think its about done.  The paper backing is on securely, with some wrinkles, but its a learning experience.

[RJonesRCRV]

 
 

I did some sanding amd added a good coat of wipe on poly.  The paper backing actually looks natural to me, as it transitions to the wood, almost as if it is a layer of bark that has been stripped away.  

As for the sight window,  I dont want to take too much more off so I am going to leave it alone for now.  If it poses a problem I can just do something later.