Violin Forum/Message Board

Menessis · Junior Member Joined: 06 Mar 2008 Posts: 10

OK I happened upon this site. http://www.scavm.com/awfribs.htm Kind of an interesting way to bend ribs. And since I don't have a bending iron I thought it may be worth a look. Has anyone else done it like this? Any thoughts or opinions?

Thanks

Menessis

agapetos · Junior Member Joined: 20 May 2008 Posts: 8

Great advices! That is what I was looking for... It is hard for me as a beginner to have all those fancy tools. This article saved me a lot of headache.

Menessis · Junior Member Joined: 06 Mar 2008 Posts: 10

Well I tried it on a "practice" piece of stripped maple. Didn't want to bend for me. In fact it seems like it got harder to bend ! More britle ???

Menessis

byacey · Posted: Sun May 25, 2008 4:08 am Post subject:

This is essentially how I do my ribs, except I bring mine to a boil after soaking overnight and simmer for about 20 minutes. Even heavily flamed maple bends easily. In fact, I've yet to ever use a bending iron, I Don't even own one.

agapetos · Junior Member Joined: 20 May 2008 Posts: 8

So you are always bending sides using technique described in this topic?

byacey · Posted: Sun May 25, 2008 3:21 pm Post subject:

agapetos · Junior Member Joined: 20 May 2008 Posts: 8

So than you just wait for it to dry out? Well... it could not be more than a few days, right? Hmm... Idea

seams logical... i have always wondered how does heat affect aesthetic of the wood, and also - it's sound quality...

byacey · Posted: Sun May 25, 2008 3:55 pm Post subject:

Once they're clamped in to the forms, throw them in a 200 degree F oven for an hour and a half or so, and they're done. You can cut, bend and glue the ribs up to the blocks in same day.

This is of course assumes your wife doesn't take exception over discovering hardware and wood in the kitchen oven.

Chet Bishop · Posted: Sun May 25, 2008 8:53 pm Post subject: bending ribs

I use a clothes iron with wooden bending molds to bend my ribs for both violins and violas. It works fine-- I dip the rib in water just before I put it in the bending apparatus, but no other heat is applied.

I do use a bending strap...As I lay the wetted rib on the clothes iron, the bending strap immediately transfers enough heat that I can hear the water sizzling. I let the rib heat flat against the iron for at leas tten seconds before attempting to bend, and then, transitioning to areas not yet heated, I make sure and allow them to heat all the way through, same as the first section. I keep some sections of twine on hand, to wrap up each section after it is bent-- I leave them on the mold until they are cool and dry.

It goes quite quickly, and after learning to get my ribs down to 1mm before attempting to bend them, and to allow the heat to travel all the way through the wood before beginning the bend, I quit breaking ribs. If you make a full set of bending molds, (six in all, plus the four little cauls for the recurve at the corners), you can bend all the ribs for one violin or viola in about ten or fifteen minutes.

Menessis · Junior Member Joined: 06 Mar 2008 Posts: 10

Well it sure sounds easy. I have tried it both ways. Didn't want to work. If I keep the iron on the wood extra long (just to see what happens) the wood dried up and became stiff!

When bending the lower bout, you need to start on the tight bend. I'm not following how to get it started. The article says to heat it and use the backup metal as the form. So I heat the wood for a count of 10 after wetting it first of course. Attempt to bend it to shape. If it feels like it isn't going to go what are my options? Re wet it and reheat it?

What is the finished thickness of the "c" bouts. Could they be a little thinner then 1mm? Would this make it easier to bend?

This is frustrating....when it should work as advertised but I just can't get it to work for me Sad

Menessis

byacey · Posted: Mon May 26, 2008 12:43 am Post subject:

1mm is about average. If the wood has exceptional figure, you may want to thin it a little more where the sharp bend is. I can't comment on using the iron because I have no experience with this.

I can tell you by soaking and boiling the rib material, it isn't going to dry in the short time they are being bent. They are right out of 100C water when I bend and clamp them in the form.

If the wood doesn't bend smoothly, it either isn't wet or hot enough, or both. Don't force it; you can always wet the wood longer or apply more heat until it does bend easily.

Menessis · Junior Member Joined: 06 Mar 2008 Posts: 10

OK, I suppose it doesn't matter how it gets done as long as it gets done! Smile

If I boil the wood and after an hour in the pot it still doesn't want to bend, I have to put it back into the pot? It's at 100'c it's not going to get any hotter, or wetter. I guess this is one point I don't understand.

My wood strips are 45 mm wide. I think It would help if I trimmed them down to say 35mm first.

I also noticed that my test piece picked up the pattern of the plywood form. I didn't seal it so maybe the plywood is swelling a bit.

I also came across a person who built an electricly heated strap! But that was a long time ago and I have no idea how to find it again.

I don't have any extra pieces to experiment with now. I guess I can cut some of a piece of maple I have for a neck. Its too wide anyways.

Menessis

PeterG · Posted: Mon May 26, 2008 10:27 am Post subject:

I tried bending ribs like that and it does work but I found it a bit cumbersome. Time consuming to make the molds and not very versatile. I invested $20 in a propane torch and use it with a piece of steel pipe clamped in a vise and bend my ribs the old fashioned way. Wet the rib, use a backing strip, and go to it. You soon learn how to not burn the wood and your fingers.
Simple inexpensive apparatus with infinite versatility. The cold bending stuff went into the discard pile.

byacey · Posted: Mon May 26, 2008 10:35 am Post subject: Re: Rib bending

Menessis · Junior Member Joined: 06 Mar 2008 Posts: 10

Yes you would think that after an hour of simmering it would be easy. The wood grain is very "wavey". The wood breaks with the grain of course and the brake has a 45' edge to it. So the grain is so wavey that it goes through the rib front to back at a 45.

How should the ribs be cut from the stock. I didn't cut these ones so I don't know exactly how it was done. I would assume that the grain should be the same as the linings right?

I do have a number of torches and have seen different ways to make irons using them. I even thought of using a "dolley" I have for sheet metal work. It's about the right shape. Weld a stake to it and heat it with the torch.

Menessis