Helpful advise needed !

[Bryan Adolphe]

 Well i finally got these replacement limbs mounted and nocks roughed in , at what point can i put a string on and bend these limbs to check tiller and weight?
- do i need to round over the glass before i continue ?
- and can i take it right to brace ? 
 

Cheers Bryan !

[kennym]

I'd sand the limb corners over a bit first to prevent lifting a splinter, then I take mine right to brace.

Nice job fitting those to riser!

[Crooked Stic]

That looks good so far. Yeah round those corners first then your fade tiller and get them pulling straight. Be sure your string does not bind in the grooves and give a false reading on pulling straight. I find it good to have the overlays on the tips and pretty much shaped so nothing is binding at all.

[Mad Max]

What they said
I have my tip over and under lays on before bracing.

[Bryan Adolphe]

I am pretty happy with the way they fit but it wasn’t without a bit of cussing , fitting them to the riser wasn’t bad it was drilling the bolt and pin accurately to match the riser they almost went to the scrap bin  I don’t want to do that again without a jig.
My questions today 🙏 is  when it comes to take down limbs the only Jig I seem to be able to find is the Bingham‘s I recall reading back in the archives possibly someone else  marketing a jig for drilling limb bolts  but my research has come up empty; is there a better way ?
My next ? Is about strings do most of you build your own or do you buy ? I learned how to build a Flemish string 20 yrs ago when I built my daughter her first bow for some reason I have forgotten how 
 Thanks guys I really appreciate your input and your ideas I’ve been able to spend a little more time out in the shop with my back slowly feeling better it’s been a real bummer  not being able to get out and hunt for the first time in almost 50 years ,  I will say this you don’t know how much I appreciate the Tradgang , the  hours and hours I spent reading hundreds of past posts trying to teach myself how to build a bow has got me through some pretty tough times the last five months  trying to get this back to heal without going to surgery so I super appreciate  all of you here    after I get these limbs to bend I’m on to bigger and better things finally Kenny’s FHLB  looking forward to a glue up in the next few days . Cheers Bryan

[Buggs]

I like your "new" sander Looks like you got it all cleaned up and functioning

[Kirkll]

Like said above, just knock the edges off the glass with 120 by hand.

 I take a file and nock the edges off the string grooves a but too so it doesn’t cut the string, and use a shallow depth on the grooves for my first time stringing it, and adjust the depth as needed for tracking issues. Then I put the overlays on after I know I hit draw weight, and the limbs are tracking straight.

It’s real important to draw it just a few inches at a time right after you string it and carefully watch the limbs closely to insure they are not going sideways on you.
I use a peg on a bench to do this so I can hook the riser on the peg and watch both limbs while I ease it back…… if the limb is tracking off center one way or the other, just deepen the string groove on the same side it’s going sideways to bring it back to center. If its off real bad, sometimes to need to deepen the grooves on both top and bottom limbs on opposite sides.

Limb alignment and tracking is probably the most critical part of tuning recurve limbs.

You are going to get a lot of different suggestions for a self centering drill jig for limbs and risers. The Binghams jig will work…..but it’s far from perfect, and will drive you nuts eventually. 
Then you have all the self centering doweling jigs out there. That was my second choice of drilling jigs, and they are more accurate than the Binghams jig…. But… you have to be careful flipping your riser end for end, and always keep your drilling jig on the same side of the riser block and limbs orientated the same.

The next hand drilling drill jig method is having a steel drill guide block machined. I’m sure some of the guys here have some of these they can post a picture of. I got rid of mine after I purchased my vertical milling machine. The mill is the best way to go for accuracy, but trust me…. You can still get things off if you are not very precise.

You will find out very quickly there really in no such thing as a true self centering jig…… If you are off by .005 on your location pins, it can throw your limb tips off center a lot.

Hopefully you mounted your limbs full width, and marked a center line before shaping you limbs an filing string grooves. If not it’s a crap shoot.


I use a string builder for my finished Flemish strings, but I still build endless loop strings if I’m in a bind and need a string I don’t have in stock. You can build a jig easily for endless loop strings, but….. that’s a learning curve too building strings, and personally…. I hate building strings.


Hope some of this stuff helps…..  Kirk

[Bryan Adolphe]

The sander is working awesome iam glad i went for it .
Thanks for the info i am a little worried about one limb that is not perfect alignment so Kirk thanks for the tip on depth of nock i may need to adjust .
Yes not sure but looking at the Binghams jig i just cant bring myself to purchase that it just doesnt scream quality lol. It was very difficult to drill those limbs to match a riser , i did run a string and found centre the best i could thats when i laid a straight edge and found out my one limb is not in line  so will see how it goes! Thanks Bryan

[Kirkll]

This type of drill guide will do fairly well keeping things in line and spaced the same on limbs and riser blocks.

But..... beware of doing everything from one side of the riser and the matching limb side. if you start flipping the jig end for end on limbs and risers you'll find out its not exactly true center. 

But these type drill guides the  drill guides themselves can be changed to different sizes and switched around on the jig location too. So you drill one end of the riser, then switch the guides around and just slide the guide body down to the other end.   Same with the limbs. drill one limb, switch guide location, then drill the other limb.... Everything is from the same side of the bow the way it will be assembled.

Once you get a system down, you can be pretty darn accurate with one of these type drill guides.

https://photos.app.goo.gl/sdNcKmBX6mQp84wv5

[Crooked Stic]

If you plan on doing a lot of 3 PIECE TDs you best bet I get a steel or alum. Plate milled flat on one side then a block machined for drill bushings for drilling . The bolt hole and insert needs interchangable drill bushings and the pin holes can be pressed in so they are flush. Set up so you can drill from both sides. That way you dont need to flip the riser block just drill the same side down from the other side. That way keeping the down sides together.
I just flip the block for longbow and recurve as the centers are different.

[Bryan Adolphe]

If you plan on doing a lot of 3 PIECE TDs you best bet I get a steel or alum. Plate milled flat on one side then a block machined for drill bushings for drilling . The bolt hole and insert needs interchangable drill bushings and the pin holes can be pressed in so they are flush. Set up so you can drill from both sides. That way you dont need to flip the riser block just drill the same side down from the other side. That way keeping the down sides together.
I just flip the block for longbow and recurve as the centers are different.

 That sounds right  I would like to see some pictures of that if possible no rush if it works  👍

[Kirkll]

If you plan on doing a lot of 3 PIECE TDs you best bet I get a steel or alum. Plate milled flat on one side then a block machined for drill bushings for drilling . The bolt hole and insert needs interchangable drill bushings and the pin holes can be pressed in so they are flush. Set up so you can drill from both sides. That way you dont need to flip the riser block just drill the same side down from the other side. That way keeping the down sides together.
I just flip the block for longbow and recurve as the centers are different.

Didnt you have a couple  of these drill guide blocks milled Mike?   The first ones i saw milled didn't have replaceable drill guides. The later ones were better, but i cant find any photos of those.    Kirk

[Bryan Adolphe]

so i had to deepen the nock to help the bottom limb out and it def helped but i would like to help it a bit more , Kirk you mentioned you could also do the opposite limb ? So would you deepen same side or opposite of what i deepened on the bottom? Sorry I didn’t quite understand in your comment and I don’t really wanna bugger this up since they’re bending pretty good for The first set of limbs. Bryan

[Kirkll]

If the top limb is tracking perfectly straight, and the string is lying in the center of the limb after you let down, there is no advantage to deepening the string notches….. during this fine tuning stage you should definitely have your overlays completed.

Take great care in shaping the tip notches to a tear drop shape, and rounding over the transition where the string lays on the limb. All the string pressure needs to ride on the top of that tear drop evenly.  If the shape of the string groove isn’t symmetrical, or the width isn’t tapered back enough. More pressure can be put on one side of the tip than the other.   

Often times just balancing the shape of your string groove can help tracking issues…… but you can only go so far on narrowing up your tips before weakening them. Assuming you are using phenolic over the glass on your overlays, you can safely narrow them up to about 5/16” width inside your loop, but that is pushing it. I’ve brought them down further in the past on light draw weight bows, but it’s scary…. Those really deep string grooves with a narrow throat can easily be blown off in a dry fire situation. I always try and narrow up the overall tips when filing them deeper.

Once you have gone the max depth deepening the string grooves, and checked your overlay shape closely, if you are still off on your tracking, things can get dicey trying to alter the limb width and use trapping techniques to bring it back on track.
It can be done sometimes…. Sometimes not.

I prefer moving a location pin or addressing the limb mount angle side to side rather than screwing up my limbs. Sometimes you can alter the limb mount angle where it sets on the riser too to bring the limb tip over a fuzz with limb but overlays. Considering you already have wood overlays on the bottom of your limbs, you may be able to sand one side a bit to move the tip over a bit.

You will find a lot of what I think is bogus info on how to eliminate limb twist by sanding glass on one side of a limb to weaken it enough to move it. Or even heating and twisting them straight….I would strongly recommend not going that route. You’ll just screw up your tiller, and possibly ruin the limbs. Once you start alerting the limb width profile you can throw everything off, and loose a lot of draw weight getting things balanced out again.

Dealing with fine tuning these things and coming up with a good looking product with longevity is what makes a bowyer out of you. Other wise you are just a man who builds bows.


Sorry I got  so long winded….. Kirk

[Kirkll]

One more thought here…. Sometimes using Flemish twist strings you can get a slight difference in tracking just by flipping the loop on the string tip 180 degrees. I know this may sound petty…. But I’ve seen this a number of times where the loop isn’t centering properly on the tip shape.   Give this a try and see if it makes a difference.   Kirk

[Bryan Adolphe]

Thank you Kirk for all of this info  i do appreciate your expertise! Heres what i have now, i put 1/16 phenolic tip overlay on the back of both tips , i do wish now that i didnt file in nocks as deep as i did but next time i will know lol. When i draw the bow the string lays back down nice and straight on the top limb but off to one side on the bottom so i deepened that side and sure enough it got better  but still lays down a bit off centre say 3/16”,  i have also not cut the string grooves in the belly glass yet which may help ? To bring the string back on centre a bit.  I will be adding 1/16 phenolic and a sliver of zebra to the belly side of tips to finish. I think this wouldn’t have been a problem if I didn’t file the knocks so deep right off the bat, both tips have 3/8 of an inch left. The limbs came in at #35@28 lighter than i was hoping but since i havnt shot an arrow for 5months it feels like a good place to be right now and a great experience for a first set of limbs and thats all i really cared about.
Do you actually file right through that belly glass for that string groove ?
This all happened because of inaccuracy and drilling those limbs Mike has giving me some good ideas thank you! And thank you Kirk and everyone for all your help ! Cheers Bryan

[Kirkll]

Here are some videos i did on tip overlays that may be helpful.  When i rough profile the width of my limbs i always leave the tips 1/8" wide  (3/4") and when i do the first string up i file in the grooves pretty shallow leaving a 1/2" between the grooves. This allows me to go deeper on either side for tracking adjustment.

Kirk

[Roy from Pa]

[Kirkll]

This doesn't work well on glass bows sanding the edges like your drawing shows Roy.  I wouldn't advise this procedure for guys just getting started. I believe this will work better on wood bows than glass.   Kirk

[Crooked Stic]

I would have to agree that side sanding has never really worked well for me. Start with tips wider than you want and deepen the grooves to get them pulling straight.then dress your tips to right width. Although most times (Not always) if your lam grind is good and profile marked right center will be center.