Trad Gang
Main Boards => The Bowyer's Bench => Topic started by: John Malone on January 03, 2018, 09:01:00 PM
-
My first attempt at a flat bow. Red oak 69 inches t2t, 1 and 5/8 at the fades out to just past mid limb down to 3/8 tips. My tape measure says its even. The string is there so I don't draw past 24 inches which is #47 so I'm hunched up a bit. My target is #50 @28.
(https://i.imgur.com/WSKNdDEl.jpg)
(https://i.imgur.com/WMoxFc9l.jpg)
(https://i.imgur.com/Qrza4hol.jpg)
-
John, the tiller looks good. The upper limb looks like it may have a little twist. Check the thickness, side to side out the limb. It could also just be an optical illusion.
-
Thanks Pat, I checked the thickness and used another tool I made no twist.
If I'm pulling 47 @24 Were should I stop dropping weight? My goal is #50 @28 and I know it will lose some shooting in. Ive read to stop an inch short, so #50 @27 still tillered to 28 then when its shot in it should settle at #50 @28?? I thought of tillering to #55 shooting in then maybe sanding to get it down if its still over??
That's my main objective with this one is to hit my target weight when its finished.
-
Give it a few scrapes full length on both limbs. This will remove weight without changing tiller.
I think the horizontal lines in the background and especially with the different widths and shadows up top is what was throwing my vision off.
-
Not bad, John. Looks like the edges of the limbs are sort of square, unless it's my old eyes. I round off all edges.
-
John if your goal weight is 50# then there's no need to stress the bow more than that. Keep pulling an inch at a time while fine tuning your tiller with the gizmo. When you reach 50#'s and your tiller is perfect, give full length scrapes like Pat describes. Pull another inch and repeat. I would stop at 27" at 50# and tiller to 28" like you asked about. You'll lose a couple pounds with final sanding.
And being within a couple pounds of your target on one of your 1st bows is good. On my 1st few if I was within 10 pounds and my bow didn't break I was happy.
-
Thanks guys, Roy I'm starting to understand the old eyes problem. I keep em slightly rounded during the process but they could use a lil more rounding going to do that next.
Pat, I took a crowd of pics still trying to find a place were the light and background works.
BMorv, I sand ALOT its not necessary I guess but I sand down to 220 at least every time a tool touches it. Nothing worse than getting a piece perfect then realize ya got a tool mark in it. Plus I found out the hard way that final sand will drop more weight than I thought.
Thanks fellows couldn't have done it without ya.
Think I know what addiction is now, the lumber store may now become my dealer.
-
John, on the rounded corner thing...as I tiller a bow I always take 3 scraped on the edges, one at about 45degs then one above and one below removing those slight edges as I remove wood from the belly. Generally it only on the belly as I have already rounded the back. Sometimes that is sufficient especially after sanding but sometimes I even round them more. The old timers(not necessarily us present) used to say the diameter of a pea. That is about a 1/4".
Do you exercise after each wood removal? Also, do you sweat the bow as you're tillering. Once I get to low brace and everything looks good I'll leave the bow braced for an hour or so. This will register any weak spots so they are not a surprise later. As the tillering progresses and everything is still OK I will increase the sweat time to as much as 5 or 6 hours near the end. I build all my bows as hunting bows and I want to know they will hold up to a long stand or hunting time. This will also help to eliminate some of the weight loss with the sanding later.
-
Dog gonnit, Pat. I only got ya by +2 years and yer calling me an ole timer? LOL
-
Pat, yes I exercise as recommended by Sam Harper in his build at least 30 slow pulls to whatever length I've got it at every time I remove or sand. I do leave it braced and sweat it as you call it, I believe it may have been one of your post were I read that. As far as edges go i don't round them near a quarter, should I?
Also i don't use a scraper i use a sanding block starting at 120 grit for the edges.
Pat i told you a lie my apologies. That limb has a slight twist right were you said. I had tuned up the width taper before i took that pic. This morning when i strung her up the string was out of line with the handle. The limb thickness back to belly was perfect but one side was slightly out of square which I'm assuming would have the same effect? It didn't take much to sand it up square, after lunch ill string it up and see but i may have put a permanent twist in it. Its not very much just real slight on the last several inches. How would i fix that? I'm usually very meticulous about putting a square on everything and checking frequently but I screwed the pooch on this one.
-
For being ole timers looking at crappy pics you fellows got some damn good eyes. Been doing this awhile have ya?
-
Been doing this awhile have ya?
Maybe.. :)
John, this might help you for reference.
Print it out..
(http://i.imgur.com/4Mr0NVK.jpg)
-
Thanks Roy. I keep print outs like that in a binder for reference for my other hobby's, guess i need to start one for bow making. I'm starting to wonder if Hank done it this away?
-
All his rowdy friends did.. :)
-
LOL well now I know you aint no millennial.
-
Generally with board bows twists is because of differences in thickness and usually only shows up under tension, braced. Sometimes it could be the way the board was sawn with uneven ring thickness. With any selfbows a little twist doesn't hurt the bow but if uneven enough the twist will increase the farther the bow is drawn.
-
Well got the twist out but you brace it and the string goes right outa wack. Checked the alignment t2t through handle its good unstrung. Filed nocks as far as i dare no good. Checked every edge for square and thickness its all good. It didn't do this till i got it tillered down? Never had this happen even the bows that came out bad had good string alignment. I don't know how to explain the grain but is slightly different on one side of upper limb. I cant trim the handle any further so I'm going to shoot it as is with the side string is closer to as strike plate. Its almost a center shot. Can i do that? Going to anyway if i cant fix it.
-
It's probably the grain causing it. Be careful shooting it if it's too bad.
-
Hold my beer and watch this $%^&.
-
LOL
-
I figured it out guys, to embarrassed to say what it was but it all makes perfect sense now.
Well ill do it for the new guys in case their reading this. When you make a flat bow or any bow that tapers at some point make sure ya round them shoulders out nice and gradual like, but most importantly make sure they match! The twist showed up after the pic was taken and i had just adjusted the taper to the tip and didn't check. It wasn't really noticeable but after putting the slide rule on it one shoulder was slightly higher. So i fixed that and now the string runs true??????? so that had to have been it.
Just like i used to tell the new guys, check double check then check it again if ya want a pay check. Plum embarrassing it is.
-
John, does the bow lay flat if unbraced?
-
Rookies. LOL glad it worked out for you. Don't feel bad, it happens.
-
Pat, no it doesn't lay flat, Why?. But I have a 6 foot piece of 2 inch steel tubing that I padded with duct tape. I put the bow on it and clamp it to my work bench at the handle area so i have a nice flat solid base to work from. I can clamp it flat if needed. That's how i found the off shoulder I traced it out on poster board then flipped the pattern over and it didn't match. When i say i used a SLIDE RULE that means I used my red neck ingenuity on some thing. Next bow i will make limb patterns on poster board and draw out the shoulders instead of eyeballing them. Lesson learned.
-
John, with a board bow it should lay flat on it's back except for any set it may have taken. You should also be able to see where the twist is. With a sawn board, ring variation could cause twist even if the limb thickness is even. In that case you'll just have to tiller the twist out. If you can draw the bow to full draw and that eliminates the twist, it's good to go. With a wood bow full draw is where it matters.
-
Thanks Pat, It will lay flat as you described i thought you meant t2t flat. Didn't see any twist like that unstrung then i thought of checking my shoulders. Cool thing is it had one inch of set from the start now it has two which means i only put an inch of set in it which is good from what I've read about red oak. I was going to ask about tillering that out if I encounter one that needs it.
As far as wood bows and full draw is all that matters I've read that concerning staves, so I'm assuming it applies to boards as well?
-
Happy to be "listening" in on this discussion. Great insights.
-
I follow your post to Sam, it is a great way to learn. Just so ya know my limbs are even lengths and tillered even as I shoot three under like you.
-
The bow measurements match at 5 inch intervals when drawn to different lengths. Cant get a good pic so I took two with the bow flipped around in each. Have messed with it all day. Still got #52.5 @28 so its still possible to come real close to my goal of #50 I hope.
(https://i.imgur.com/HuosBosl.jpg)
(https://i.imgur.com/PZFX4BPl.jpg)
(https://i.imgur.com/iDdZ0kQl.jpg)
(https://i.imgur.com/7bysCMvl.jpg)
-
How bout this one?
(https://i.imgur.com/J8nn7vBl.jpg)
-
Looks from here. Make sure you exercise it fully. Had to many break on me lucky my face was not mince meat.
-
Just above mid limb on the top looks a little stiff for about 8" then a slight bend before the tip.
The upper fade could bend a bit more too.
You're getting close. Have you shot it yet. If not, do so. Put about 10 arrows through her then check full draw again.
-
Gonna try tomorrow Pat, Its cold out there. Real cold.
-
The right limb area outside of the fade looks a tad stiff where the flat line is. Where the arrow is looks a little weaker. Then stiff out past that. I would work above and below that arrow, not touching the arrow area at all. Just a few scrape's then sand then exercise.
Do you have a gizmo? They do not lie.
(http://i.imgur.com/i8vSLyE.jpg)
-
I see it this morning. Yes I have a gizmo, going to modify it today with a better pencil adjustment on there. Some how it went sailing across the shop last night. When things start magically flying around I know its time to stop.
-
Hah!!!!I figured that out. I like it. But I know darn well Hank didn't do it this away. Thanks for the inspiration Roy. An NC hillbilly cant get showed up by one from PA. lol
(https://i.imgur.com/jt3RLIhm.jpg)
-
You have been healed.. :)
-
I hate window 10! they changed it all up. Kinda of reminds me of when beer company's switched to all twist off tops.
-
Modified gizmo. Its a prototype, still the exact same thing just a better pencil adjustment. The other was tight but I swear I could feel it move most likely my imagination. If I like it I have an idea for installing a tiny ruler for adjusting in 1/64 increments. Not necessary I know but neither is a 300 blackout for coyote hunting but hey why not!
(https://i.imgur.com/IiGVCKTl.jpg)
-
I give up for now, down to 49.7 pounds @28.
(https://i.imgur.com/iORRNZ9l.jpg)
-
Looks nice, gizmo too.
-
I put ten arrows through it this morning as Pat recommended then a few dozen more this evening. The windage is good hits pretty much were I'm looking at 12yrds or so. However I do not like the way it shoots. It draws good but it feels clunky on release if that makes sense. Hand shock isn't to bad. I went parallel to midlimb maybe a tad passed. Ill shoot it some more and see. Working on a new one and the taper starts 6 inches out going to see how that shoots and maybe come back to this one and do some modifications. In your guys experience is that normal for this type of bow. Pat I know your build along is similar just curios. Probably the bowyer not sure. Going to break down and buy a long bow so I will have some comparison.
Thanks guys.
-
Some times I speak to soon. I cranked the brace height up to 7 inches swapped to a heavier arrow seems much better. Cant say she's fantastic but not bad imo. Put at least 200 arrows through it today checked and it was 47.8 pounds at 28 so. The cool part is the set, it had one inch to start now its lil over two much better than the last few wich started flat and ended up well over two inches. On to the next one.
(https://i.imgur.com/bTY7Amim.jpg)
(https://i.imgur.com/pdZAvYsm.jpg)
-
Looking good John.