Trad Gang.com Post New Topic  New Poll  Post A Reply
MY PROFILE | directory login | register | search | FAQ | forum home

  next oldest topic   next newest topic
» Trad Gang.com » Main Forums » The Bowyer's Bench » Inner tube clamping method (Page 1)

 - UBBFriend: Email this page to someone!   This topic comprises 2 pages: 1  2   
Author Topic: Inner tube clamping method
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
Hello guys.

After my recent failure, I'm rethinking my working methods. One of the is my clamping method. I use F clamps and I'm thinkg of moving to bicycle inner tubes clamping. Question is what's the better way- cut to small band and wrap over dowels or use a long rubbet strip and wrap the whole form with the bow laid on it? Do you use a pressure strip or do you wrap directly on the bow?

Any other info regarding this method would be welcome.

Thanks

Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
Shredd
Trad Bowhunter
Member # 45311

Icon 1 posted      Profile for Shredd   Email Shredd   Send New Private Message       Edit/Delete Post   Reply With Quote 
Go air hose... You won't regret it...
Posts: 270 | From: Florida | Registered: Sep 2016  |  IP: Logged | Report this post to a Moderator
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Shredd:
Go air hose... You won't regret it...

The main issue is the form.. I can't get the hardware.
Is there a way to get the hardware myself?
There's no bow making supplier in Israel and ordering from Bingham is pretty costly.
Are there "simple substitutes" I can get at a regular hardware store?

Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
Bvas
Trad Bowhunter
Member # 44555

Icon 1 posted      Profile for Bvas   Email Bvas   Send New Private Message       Edit/Delete Post   Reply With Quote 
I use dowels and long continuos bands. Then I just wrap back and forth between dowels making two passes. But I still clamp the riser in place. And yes, you need to use a pressure strip. Something with a slight raise in the center to make sure you get pressure in the center not just the edges. I use contact cement to glue lamp cord to the center of mine.

I like the bands over the air hose.....at this point. Mostly because I'm more into experimenting, then producing the same bow over and over. The bands allow me to change the riser style or size for a specific bow without having to build a new form.

--------------------
Some hunt to survive; some survive to hunt

Posts: 740 | From: Ohio | Registered: Feb 2016  |  IP: Logged | Report this post to a Moderator
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Bvas:
I use dowels and long continuos bands. Then I just wrap back and forth between dowels making two passes. But I still clamp the riser in place. And yes, you need to use a pressure strip. Something with a slight raise in the center to make sure you get pressure in the center not just the edges. I use contact cement to glue6 lamp cord to the center of mine.

I like the bands over the air hose.....at this point. Mostly because I'm more into experimenting, then producing the same bow over and over. The bands allow me to change the riser style or size for a specific bow without having to build a new form.

Same here.
Since I'm really a beginner in making glass lam bows, I want the most cost effective method.

Do you get good pressure at the fades with just bands? Or do you use clamps there?

Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
monterey
Trad Bowhunter
Member # 15276

Icon 1 posted      Profile for monterey   Email monterey   Send New Private Message       Edit/Delete Post   Reply With Quote 
I learned a lot about rubber band method by making more mistakes than I'll admit to. [Smile] I also learned a lot from members of this forum.

I too like the ability to make changes in design without making a whole new top half. I have and occasionally use hose forms but since learning some hard lessons rubber bands are my preference. If I ever arrive at the perfect design I'll do a hose form for it.

Later today when I can get to the desktop I'll do another post with some pictures. I'm not doing well with Imgur and a smartphone. [Frown]

--------------------
Monterey

Posts: 2971 | From: Colorado | Registered: Feb 2008  |  IP: Logged | Report this post to a Moderator
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
Thanks Monterey.
Looking forward for your post

Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
Pat B
Trad Bowhunter
Member # 477

Icon 1 posted      Profile for Pat B   Email Pat B   Send New Private Message       Edit/Delete Post   Reply With Quote 
I've not worked with glass but on hickory backed and boo backed bows I cut the valve section out of the tube and cut it lengthwise making 2 long bands. After glue u I wrap the bow, starting at the handle and working out each limb then I clamp it to the form. THe banded bow blank will bend to shape if not too drastic.

--------------------
Make the most of all that comes and the least of all that goes!
TGMM Family of the Bow

Posts: 13166 | From: Brevard, NC. | Registered: Apr 2003  |  IP: Logged | Report this post to a Moderator
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Pat B:
I've not worked with glass but on hickory backed and boo backed bows I cut the valve section out of the tube and cut it lengthwise making 2 long bands. After glue u I wrap the bow, starting at the handle and working out each limb then I clamp it to the form. THe banded bow blank will bend to shape if not too drastic.

I used this method too Pat, when I was making wooden/boo backed bows. Worked great but I don`t thinks it`ll work with FG bows
Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
KenH
Trad Bowhunter
Member # 40173

Icon 1 posted      Profile for KenH   Author's Homepage   Email KenH   Send New Private Message       Edit/Delete Post   Reply With Quote 
I use diameter loops of bicycle tire rather than long strip. The rings are about 1" wide. I'd post a photo but I haven't recovered them from Photobucket's power grab yet

I've made some pretty radically curved bows (Scythians) that way, with loops every 6" or so along the form. The loops go over 1/4" dowels, in holes drilled through the form, extending about an inch either side. Most often I use two rings of tire looped together to make a figure 8, and a pressure strip on top of the glue-up.

--------------------
Living Aboard the s/v ManCave

Posts: 655 | From: FL | Registered: Oct 2013  |  IP: Logged | Report this post to a Moderator
Bvas
Trad Bowhunter
Member # 44555

Icon 1 posted      Profile for Bvas   Email Bvas   Send New Private Message       Edit/Delete Post   Reply With Quote 
The hardest part to get pressure is not the fades. It is the deepest spot on the belly ramps(if that makes sense). I agree with others that it is best to start at the handle and work towards the tips.
It seems easier to control everything if you start at the tips, but it is much harder to get the lams pulled in on the belly ramps that way. I would also suggest doing four thinner core lams instead of two thicker ones. It is a lot easier to pull two thin lams into place instead of one thick one. And the more gradual you can make your curves, the better off you will be.

--------------------
Some hunt to survive; some survive to hunt

Posts: 740 | From: Ohio | Registered: Feb 2016  |  IP: Logged | Report this post to a Moderator
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Bvas:
The hardest part to get pressure is not the fades. It is the deepest spot on the belly ramps(if that makes sense). I agree with others that it is best to start at the handle and work towards the tips.
It seems easier to control everything if you start at the tips, but it is much harder to get the lams pulled in on the belly ramps that way. I would also suggest doing four thinner core lams instead of two thicker ones. It is a lot easier to pull two thin lams into place instead of one thick one. And the more gradual you can make your curves, the better off you will be.

I got it.
It seems this failed bow made me learn so many important lessons I can almost consider it a sucsses [Wink]

Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
monterey
Trad Bowhunter
Member # 15276

Icon 1 posted      Profile for monterey   Email monterey   Send New Private Message       Edit/Delete Post   Reply With Quote 
Ok, lot's covered in the posts above and I'll probably repeat some of it but here goes.

The form:

You need stout dowels of at least 3/8" or 7/16". Use real hardwood dowells. Many of them are made of soft wood that easily breaks. You can put side stops on the form using a single wood screw that allows you to loosen them or tighten them as needed.

There is no formula for how far apart they should be or how far from the form surface, but leave about 1 3/4" working space between the dowells and place them about two inches from the form surface. Mine extend out two inches on each side.

My forms have end stops and the lams are cut to fit exactly to the stops. If not exact, definetly not too long. trial fit to be sure that there is no tension on the lams between the stops when they are fitted.

I use five full bike tubes for each layup. They are cut as already described above by cutting across on each side of the valve stem and then cutting around the tube for full length bands. I cut four per tube.

This is what it looks like after it's banded down.

 -

I put a lot of pressure on the bands when applying them but also try to bring the band over the top and then and stretch down the other side without pulling across the stack.

My form in the picture does not have provision for applying a clamp to the riser, but all of them will be modified to do so before they are used again. I found centering the riser and clamping it down with just bands to be pretty simple with an ASL, but NOT so with this RD.

My fit of the riser to the lams in layup was very good. I think it helped that I did not fit the riser to the form, but rather tied all the lams that go under the riser tightly into the form using the dowels and then placed the riser block up against the side of the form and drew a pencil line of the actual fit. So this was just a blank riser block about a half inch over length on each end. Then I sawed outside the line and carefully sanded on a belt sander to a perfect fit. All before cutting out the ramps and tapering the fades in. If you try to sand this to fit on a drum, you are headed for disaster unless you are an absolute artist with a sanding drum.

Guys with better tools and bigger brains have simpler solutions to this but until I get better tools and a bigger brain I'll stick with my primitive ways. [Smile]

Regarding the post above by Bvas, I concur with everything he says.

You simply must get your ramps and fades as perfect as possible. I take mine to a bout 1/32 to 1/16 of the line with a drum and then do the rest with a flexible sanding stick. I do the final shape and feathering on a piece of thick mirror (any piece of thick glass will do) like in the photo below. it;s time to make your surfaces as perfect as possible to get any dips out of the ramps and to get your fades as thin as possijble.

 -

Your sanding slab needs to be flexible enough that you can follow the curve you already made but not flexible enough to flow into the dips left by the drum sander.

Lastly and very importantly, the pressure strips. If your strips are too thick and stiff, they become part of the problem in getting the top lams pulled down tight to the riser. If they are not a bit thicker in the centerline and thinning toward the edges the center of the stack will not be forced down tight. If the edges are too thin they will put a slight curl in the layup edges.

Here's what the pressure strips look like for this layup. They are about 1/8" at the centerline and about 3/64" at the edges. If you steam them and prebend the pressure strips in the ramp area they will tighten down easier.

 -

 -

I've also done similar to Bvas does with the electrical cord glued down the centerline and that works good. Only difference is I used a piece of 1/4" poly rope.

At this point, the thing that can kibosh your lay up on the ramps are pressure strips that are too thick and inflexible and lams on the ramps that are too thick and difficult to bend (that can be a problem with a hose form also if the top half doesn't fit well). If, for example, you are going to use three core lams, Put the taper(s) under the riser and plan the stack so the third lam on top is a parallel as thin as possible. In the bow I'm using for illustration here, there are no core lams on the top. There is one taper and one paralel under the riser and just stabilcore and glass on the top.

Just for clarification, in the future I'll be using at least three core lams and probably one of them will be very thin and go on the ramps.

The suggestion already made to have your fades taper at a rate of 1/16" for the first inch can't be overemphasized Thats a "no more than 1/16" recommendation. If you have the skill and patience to taper even slower, do it. Also, keep those glue joints out of the fade area as already mentioned.

Ok, that's it for now. Hopefully others will chime in with more suggestions. I'm no expert and I'd like to learn a few new things here too. [Smile]

--------------------
Monterey

Posts: 2971 | From: Colorado | Registered: Feb 2008  |  IP: Logged | Report this post to a Moderator
arachnid
Trad Bowhunter
Member # 45147

Icon 1 posted      Profile for arachnid   Email arachnid   Send New Private Message       Edit/Delete Post   Reply With Quote 
Montrery, many thanks for this great info.
My brain is already working on planning the next bow...

Posts: 219 | From: Israel | Registered: Jul 2016  |  IP: Logged | Report this post to a Moderator
Bvas
Trad Bowhunter
Member # 44555

Icon 1 posted      Profile for Bvas   Email Bvas   Send New Private Message       Edit/Delete Post   Reply With Quote 
[clapper] [clapper] [clapper]
Nice tutorial Monterey!!
I think you nailed it.
I only do a couple small variances.
I also use the stops at the ends of the form, but I set them about an 1/8" long so there is no chance of binding. I also use an 1/8" dowel to pin my backside lams to the riser. I don't pin them to the form, but put a black center line on the riser, lams, and form so I can make sure they stay centered.
And as mentioned before, I do use clamps on the riser as seen here.
 -
Also, make sure you have a staple gun, screw gun or something else handy to anchor bands with. If one breaks you want to be able to hold it in place with tension so that you can carry on with a new band instead of starting over. And don't forget to do a dry run!!!!

--------------------
Some hunt to survive; some survive to hunt

Posts: 740 | From: Ohio | Registered: Feb 2016  |  IP: Logged | Report this post to a Moderator
  This topic comprises 2 pages: 1  2   

Quick Reply ~ PLEASE THINK BEFORE YOU POST! - Is your post trad bowhunting related? Check the FAQ or EMAIL if you're unsure!
Message:

HTML is not enabled.
UBB Code™ is enabled.

Instant Graemlins
   


Post New Topic  New Poll  Post A Reply Close Topic   Feature Topic   Move Topic   Delete Topic next oldest topic   next newest topic
 - Printer-friendly view of this topic
Shoot On Over To:


Contact Us | Trad Gang.com © | Privacy Statement

Copyright 2003 thru 2017 ~ Trad Gang.com ©

Powered by Infopop Corporation
UBB.classic™ 6.7.1