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Bias tape question
http://w-ww.luthiersforum.com/forum/viewtopic.php?f=10101&t=17174		 Page 1 of 2
Author:  Jeremy Douglas [ Tue May 13, 2008 10:58 am ]
Post subject:  Bias tape question
I'm getting ready to glue down the kerfling on my top rim but first a question... I want to use the bias tape as side reinforcements but I haven't contoured my back rim yet. Can I plane and sand the rim after these strips are installed?
Author:  Hesh [ Tue May 13, 2008 10:59 am ]
Post subject:  Re: Bias tape question
Yes - bias tape sands and planes fine assuming that your plane is good and sharp.
Author:  Hesh [ Tue May 13, 2008 11:05 am ]
Post subject:  Re: Bias tape question
I should have added that I install the tapes after the sides are profiled, then I glue on the kerfed linings, then I sand in the dish.
Author:  Alexandru Marian [ Tue May 13, 2008 11:37 am ]
Post subject:  Re: Bias tape question
Hesh , if I may ask, I remember you said that the tape goes across the entire width of the sides. Are you notching the linings a little? If not, you will have a tiny gap between side and lining for about a 1/4" on each side of the tape. I know I am really splitting hairs here [uncle] :mrgreen:
Author:  WaddyThomson [ Tue May 13, 2008 12:28 pm ]
Post subject:  Re: Bias tape question
I have wondered about that too, and that little gap would create weak glue joints at the lining/side joint for the 1/4 to 1/2 inch where there is a slight gap, particularly if you are using hide or fish glue with poor gap filling properties.
Author:  Hesh [ Tue May 13, 2008 1:37 pm ]
Post subject:  Re: Bias tape question
Alex and Waddy no notching of the kerfed linings which is one of the beauties of using bias tape - it is very easy to use.

I can't measure it right now because I packed that part of my shop this morning but the gap is very minor because the tape is very thin and the kerfed linings are simply glued on top of the bias tape.

This is the traditional way to install it ala Martin and Gibson so I wouldn't stress over the minor gap - many instruments have been built this way and have survived 100+ years.
Author:  Jeremy Douglas [ Tue May 13, 2008 1:49 pm ]
Post subject:  Re: Bias tape question
Thanks Hesh, I just got back from getting the tape.
Author:  Alan Carruth [ Tue May 13, 2008 1:49 pm ]
Post subject:  Re: Bias tape question
The gap is .005" or less, and only right at the edges of the tape. I use HHG for both the tapes and the liners, and find no adhesion problems that I could attribute to the gap. Some of the students aren't as fast as I am, and have chill problems from time to time, but those can happen anywhere. I often note then routing for the bindings that the tapes are particularly tenacious, with some tape remaining even when the side is routed off on either side.
Author:  Hesh [ Tue May 13, 2008 2:02 pm ]
Post subject:  Re: Bias tape question
Thanks Al - do you mind if I ask you what you are using for bias tape, the fabric store stuff?

Thanks
Author:  Alan Carruth [ Thu May 15, 2008 12:55 pm ]
Post subject:  Re: Bias tape question
I use Wright's cotton-poly bias selvege tape. Get the narrow stuff, wet it, and iron it out flat on your bending iron.
Author:  Hesh [ Thu May 15, 2008 2:56 pm ]
Post subject:  Re: Bias tape question
Thank Al! You anticipated my next question. I have trouble ironing the Wright's stuff flat but I have never tried wetting it first - great tip. [:Y:]
Author:  Jeremy Douglas [ Thu May 15, 2008 9:15 pm ]
Post subject:  Re: Bias tape question
Hesh wrote:
Thank Al! You anticipated my next question. I have trouble ironing the Wright's stuff flat but I have never tried wetting it first - great tip. [:Y:]


That's what the spray nozzle is on front of the iron for

Btw, I went ahead and contoured my sides first because I thought of addition reasons to do so.
Author:  Alexandru Marian [ Thu May 15, 2008 9:33 pm ]
Post subject:  Re: Bias tape question
Unless I'm terribly off, there is plain flat unfolded tape easily available too. Why do you buy folded tape that needs to be tinkered with ?

Here is what I found in the drawer of our sewing machine. Not sure it is a suitable kind for guitar building, but I sure love the color laughing6-hehe
Author:  Hesh [ Thu May 15, 2008 9:47 pm ]
Post subject:  Re: Bias tape question
Jeremy buddy is that what that is for on the iron...... :D

Alex that looks like something that you might see on panties......... laughing6-hehe

Seriously the regular bias tape has a weave to it that permits it to get saturated with glue. If the weave is to tight it would not work as well.
Author:  Jeremy Douglas [ Thu May 15, 2008 9:59 pm ]
Post subject:  Re: Bias tape question
Hesh wrote:
Jeremy buddy is that what that is for on the iron...... :D



you'd think it was for filling with beer cause what goes together better than drinking and using a hot iron?

"Alex that looks like something that you might see on panties......... laughing6-hehe "

yeh you might see about doing a Victoria's Secret special edition guitar
Author:  Alexandru Marian [ Thu May 15, 2008 10:12 pm ]
Post subject:  Re: Bias tape question
[headinwall] I knew I wont have luck with it.

It's not only very tightly weaved, it's also rather thick.

Bright ideea no2: how about cutting the insect net off the windows? Better from a neighbor, this way your wife not going to kill you. Pick your annoying neighbor, the mosquitoes will get him.

rubbish 6am humour, spent the night kerfing a bunch of linings.
Author:  Hesh [ Thu May 15, 2008 10:23 pm ]
Post subject:  Re: Bias tape question
laughing6-hehe

Jeremy buddy I have to admit that I thought the same thing only scotch came to mind..... :D

Alex my friend you are right on track. I have been looking for something better then bias tape because on the 1930's Gibsons that I have seen, Joe White has one and David Collins had one that I saw in his shop, what they used had less of a weave to it then bias tape does. It's not quite window screen but more in that direction.

The other problem is that I tried some linen fabric and when I cut it to size the edges fell apart...... So at least the bias tape has substantial edges that won't unravel.

Lastly since bias tape is a poly blend when you iron it the poly approaches melting far faster then the cotton approached burning and linen/cotton is one of the highest settings on the stinkin iron. I think that I noticed that once ironed it does not let the glue penetrate it as well. So this tells me that all cotton would be a better bet.
Author:  Jody [ Fri May 16, 2008 6:24 am ]
Post subject:  Re: Bias tape question
has anyone considered fiberglass mesh tape ( drywall tape) for use as bias tape? it is thin , has a mesh for glue penetration,like window screen but flatter , it is sticky on one side so it will adhere to the rims until glued in place... just a thought , it is the base for fiberglass automobiles too , so it has strenghth .. Jody
Author:  jhowell [ Fri May 16, 2008 8:04 am ]
Post subject:  Re: Bias tape question
Don't know about drywall tape, but I have considered using kevlar similar to this from Jamestown Distibutors:

http://www.jamestowndistributors.com/userportal/search_subCategory.do?categoryName=Kevlar&categoryId=523&refine=1&page=GRID

I'm still looking to find it in 1/2" width and If I do I'll post a link. It has the added advantage of personal protection if you are playing the 'chicken wire' circuit! laughing6-hehe laughing6-hehe

Edit-- another link that shows promise:

http://www.cshyde.com/Tapes/Data/kevnominfo.htm

This stuff is about 0.06 in thickness and may have to be inlet into the linings -- dunno for sure, but I don't think that you can beat the strength to weight ratio with any other fabric.
Author:  Alexandru Marian [ Fri May 16, 2008 9:03 am ]
Post subject:  Re: Bias tape question
I dunno, but the ideea of using fiberglass or kevlar inside one of my guitars kind of makes me think at Ovation. I know about graphite neck bars, but at least no1 can *see* them!

So I think I'll make some spruce braces for my current build if I can't find a reasonable cloth tape. I bet they won't weight more than 5 grams, 10 if i make them bombproof.

One think I can't understand is why do we insist on making the endblock with the grain running the same as the side, if the neck block and side braces have the grain at 90 deg ?
Author:  Alexandru Marian [ Fri May 16, 2008 10:11 am ]
Post subject:  Re: Bias tape question
Yes exactly. Actually I should have asked, why not use side braces with the grain running in the same direction as the side? Would be the same type of stripe used as back seam reinforcement.

I really am splitting hairs again duh better go and do smth useful...
Author:  Alan Carruth [ Fri May 16, 2008 2:06 pm ]
Post subject:  Re: Bias tape question
I tested nylon twill weave tape against cotton-poly bias tape for strength as side reinforcements. I glued the tapes to standard sized samples of side wood, and found out how much force it took to break the samples. The nylon tape was much stronger as a material than the cotton-poly, but it dodn't glue well with either Titebond or HHG. The nylon tapes tended to come unstuck from the samples rather than breaking, and the samples with the nylon tapes broke at lower force than the ones with cotton-poly.

There is a place that makes linen twill tape, but iirc, you have to order 75 feet at a ime, and it only comes in white.
Author:  Hesh [ Fri May 16, 2008 7:41 pm ]
Post subject:  Re: Bias tape question
Alex buddy the primary function in life for a side tape, or brace for that matter, is to stop a crack in the side from running along the side. So we want the tape or brace to be resistant to cracking/breaking especially in the direction that the side grain is running. Make sense?
Author:  Blanchard [ Fri May 16, 2008 8:18 pm ]
Post subject:  Re: Bias tape question
I've been using Mrs. Wright's polyester twill tape for a couple of years now. I glue it with 5 minute epoxy. The epoxy sticks pretty well to polyester. The extra thickness does not seem to create any problem with the linings.

Works well for me !!

Mark
Author:  Lillian F-W [ Sat May 17, 2008 11:32 am ]
Post subject:  Re: Bias tape question
I just ordered some silk ribbon to see what it's like and if it will work. It is thinner than cotton or linen without being fragile.
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