Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 31

Thread: Production Bending

  1. #11
    Join Date
    Mar 2009
    Location
    Hudson, MA
    Posts
    1,541

    Default

    Quote Originally Posted by eclipsme View Post
    I assume bending machines with blankets? Was there no springback when released from the bender?
    I don't know....I'm a hot pipe bender and just a hobbyist. But I am a Lean Manufacturing guy in my day job so I figure the same principles will work. Identify the steps that add value and the steps that don't. Anything that involves waiting is a pure waste....heating, cooling, re-bending, drying, clamping, unclamping would all be big targets for elimination if possible. Don't even get me started on the finishing process

  2. #12
    Join Date
    May 2010
    Location
    Cairns, Australia
    Posts
    2,359

    Default

    Quote Originally Posted by eclipsme View Post
    I have never used the iron (though now thinking of it) but thought that when finished, the side is the correct shape, but then you 'set the shape in the bender'?
    If you haven't used a bending iron then you had better get one and start learning. I'd consider it a pretty much indispensable item in a luthiers shop even if it's only to touch up the shape of some timber that just doens't want to behave.

    The reason that I and many others use the iron first is that with high figure timber and or difficult to bend species going straight to a bender will far too often result in sides that end up having to be tossed in the bin. And especially with a body shape such as mine with ver tight waist and upper bout bends. The iron lets you "feel" when to apply pressure and how much without it fracturing.

    Only using a bending machine too often you are guessing if it's been heating enough and ready, or too long and the timber has dried out and brittle. You will see all kinds of work arounds by people that only use a bending machine to try and remedy this problem, when the method I describe is dead easy and has worked 100% of the time since I switched to it. About 200 instruments since the switch.

    Coming off the iron doesn't need to be perfect. Far from it. Just getting the piece to be shaped somewhat like your form is all that is required. The solid form and heat blanket and appropriate clamping does the rest.

  3. #13
    Join Date
    May 2015
    Posts
    397

    Default

    I on the other hand want my bodies to be pretty close to finished shape as I have been building without a mold. The first one I did moldless.



    The first guitar I made I did enough sides to do four guitars, a busy day. I bend the rough shape on the pipe and then set the actual shape on a mold with a heat blanket. I do two sides and then let them sit over night on the mold.



    The outer one is a little bigger than the inner but easy enough to tweak.

    I was a LM kind of guy, spent years on a production line with about 250,000 items into 20,000 cartons a shift. Things did not always go well so when handling was needed any movement I needed to make multiplied by all the repetitions added up and bogged you down. My partner and I went on vacation at the same time one year, the plant efficiency dropped from around 90% to under 50%. They never let us go at the same time after that.

    I would not sweat the time to bend wood, put a fan on the mold to cool it down to speed things up. Some woods spring back so a rough form to hold them is useful if not using in a period of time. Look up some Youtube vids of manufacturers building their guitars, Martin has a good one.

  4. #14
    Join Date
    Aug 2008
    Location
    Wales, UK
    Posts
    5,231

    Default

    This is going to be on repeat forever unless someone locks it down. There is no right or wrong way. And whoever started this post ought to put some time in going through all the old posts, youtube videos and stuff out there - there is enough info out here to make more than informed decision. We don't even need Grahams' book! (though it would be nice to have it in our 'library') And we should shut up and stop encouraging them.

  5. #15
    Join Date
    Mar 2009
    Location
    Stockton on Tees..North East UK.
    Posts
    5,053

    Default

    Quote Originally Posted by Pete Howlett View Post
    This is going to be on repeat forever unless someone locks it down. There is no right or wrong way. And whoever started this post ought to put some time in going through all the old posts, youtube videos and stuff out there - there is enough info out here to make more than informed decision. We don't even need Grahams' book! (though it would be nice to have it in our 'library') And we should shut up and stop encouraging them.
    I fully agree with this.."The Right Honourable Member for Snowdon and District" has spoken
    http://ukulele-innovation.tripod.com ebay i/d squarepeg_3000 Email timmsken@hotmail.com

    If you can believe that moving images and sound, can fly through empty space across the universe and be seen and heard on a box in your living room ?.. then you can believe in anything.

  6. #16

    Default

    Quote Originally Posted by printer2 View Post
    I on the other hand want my bodies to be pretty close to finished shape as I have been building without a mold. The first one I did moldless.

    I see you are also building with Spanish Heel construction. Cool! I could never get a clear picture of how the ribs get attached to the soundboard in exactly the stage of construction depicted in this picture. That looks like Cyanoacrylate glue, yes? Do you then use Titebond to attach the linings? Traditional, kerfed or solid?

    The first guitar I made I did enough sides to do four guitars, a busy day. I bend the rough shape on the pipe and then set the actual shape on a mold with a heat blanket. I do two sides and then let them sit over night on the mold.



    The outer one is a little bigger than the inner but easy enough to tweak.
    Yes, why didn't I realize this before? So obvious to double them up! Thanks.

  7. #17

    Default

    I found this thread very helpful, so thank you! Here is how it ended up for me.

    I steam my ribs. Then I begin by bending the rib on my side bender.

    Side Bender.jpg

    Once that is in place, I begin steaming the next rib.

    5 minutes before the steaming is done, I remove the rib from the side bender and put it into a form and caul. The rib will stay in the form for at least 24 hours. I now have 4 of these.

    Form and Caul.jpg

    After 24 hours, the rib is transferred to this - I don't know what to call it but it makes the rib maintain its shape until I am ready for it. I wet the rib down several times during the next 12 hours or so. At the end of this process, I find the rib has very little springback.

    Bondage.jpg

    I was easily able to get 5 ribs bent in a morning this way (I used the side bender as a form and caul for the 5th rib). I am now beginning on the necks while the ribs sit and stabilize.

    I hope my experience can help somebody else.

  8. #18
    Join Date
    Mar 2009
    Location
    Stockton on Tees..North East UK.
    Posts
    5,053

    Default

    Those are not bends ..those are gentle curves ..I do my soprano waists at 1" radius.

    https://www.youtube.com/watch?v=vUmyFjC5THI please note all this info and much more is available on this forum using the search function.
    Last edited by Timbuck; 08-23-2019 at 11:04 PM.
    http://ukulele-innovation.tripod.com ebay i/d squarepeg_3000 Email timmsken@hotmail.com

    If you can believe that moving images and sound, can fly through empty space across the universe and be seen and heard on a box in your living room ?.. then you can believe in anything.

  9. #19
    Join Date
    Aug 2008
    Location
    Wales, UK
    Posts
    5,231

    Default

    So from all of your research you chose, perhaps, the most painful and pointless way to do something. Listen my friend, the wealth of experience on this forum is there for the taking. Have a couple of days off from posting your ill-advised decisions and repetitive questions and do yourself a favour - THOROUGHLY research what those who have been doing this for MANY years have shared here. Go away for another day and allow yourself to process it. Then come back to us , informed and curious as to why we nearly all agree own one thing - this business is more than just arriving at the first idea that seems the easiest solution. Some operations are difficult but there former posts here made by professionals and gifted amateurs identify the pitfalls and properly guide you to the BESRT way of doing something, not there EASIEST. You are not painting yourself in a positive light my friend and people, like me who want to help people like you are reluctant to do so because you appear to be of the 'entitled ' generation who expect everything without effort, to come instantaneously to your door for free. The price you have to pay to get my help and the benefit if 25 years building ukulele ism to show you have out some measured and thoughtful effort ito this. You are not my peer but a potential pupil....

  10. #20

    Default

    Quote Originally Posted by Timbuck View Post
    Those are not bends ..those are gentle curves ..I do my soprano waists at 1" radius.

    https://www.youtube.com/watch?v=vUmyFjC5THI
    Wow, thanks for the video! So you bend the waist first and then go to the side bender. I had not seen that before. Clever way to backup the wood with a metal strap.

    BTW - Do you find that a tight waist bend improves the sonic qualities of the instrument?
    Last edited by eclipsme; 08-23-2019 at 08:51 AM.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •