Grill cloth sags

2/3/2008 2:51:40 PMJon

Hello All,
Any of you Wizards know of a trick to take out sags in grill cloth? Just finished a long restoration of a philco mod. 50(in a mod.51 cabinet) and ended up with loose grill cloth. I used up all I had of the correct pattern and used spray adhesive to apply it to the backing board.I had heard of some type of liquid that was used in model airplane construction thay would tighten up the cloth/paper wing material. Was wondering if this could be used.
Thanks,
Jon.

2/3/2008 3:04:23 PMTerry F

Jon,

First of all, I make sure the cloth is bigger than the mounting board. I use a hot DRY iron to get all of the fold seams out and I staple one end (narrowest width). I use basic Elmer's white glue and spread a small bead across the top and bottom (narrowest width) surfaces, very close to the edge of the board. Then spread it out with my finger and wipe up any excess glue (else it will show through the fabric).

Then I stretch the fabric to the other end of the mounting board, pull it tight and staple it. Let it dry overnight.

Repeat the same process with the other side of the mounting board, this will allow you to get any remaining wrinkles out.

You can leave the staples in as long as they don't interfere with mounting the board back into the chassis. You only have to iron the fabric once and just keep it straight as possible.

When you mount the board to the chassis, use a drift or awl to make holes for the screws in the fabric, else the screws will snag on the fabric and pull threads. You don't want to ruin a perfectly flat cloth with snags.

Hope this helps.

Terry F

2/3/2008 3:17:40 PMJon

:Jon,
:
:First of all, I make sure the cloth is bigger than the mounting board. I use a hot DRY iron to get all of the fold seams out and I staple one end (narrowest width). I use basic Elmer's white glue and spread a small bead across the top and bottom (narrowest width) surfaces, very close to the edge of the board. Then spread it out with my finger and wipe up any excess glue (else it will show through the fabric).
:
:Then I stretch the fabric to the other end of the mounting board, pull it tight and staple it. Let it dry overnight.
:
:Repeat the same process with the other side of the mounting board, this will allow you to get any remaining wrinkles out.
:
:You can leave the staples in as long as they don't interfere with mounting the board back into the chassis. You only have to iron the fabric once and just keep it straight as possible.
:
:When you mount the board to the chassis, use a drift or awl to make holes for the screws in the fabric, else the screws will snag on the fabric and pull threads. You don't want to ruin a perfectly flat cloth with snags.
:
:Hope this helps.
:
:Terry F

Terry,
Thanks for the responce. I did most all that you suggested, modifying the technique to suit the application but once in a while I will get one done that is still not as tight as I would like. I was wondering if there was a fix I could use without doing it all over again.
Thanks,
Jon.

2/3/2008 3:35:47 PMGeorge

Hi Jon,
I'm going to throw my two cents in on this. I had a lot of trouble getting the cloth to come out just right and getting it straight so I came up with a really good method to my madness. I went to the local fabric shop in Walmart and picked up a sheet of white flat fiber material. Make sure you can blow through it with ease so it doesn't interfer with the sound. It is like a cotton fiber mix that is 1/8" thick. I do a light coat of adheasive on the board and stick the fiber to it. Then I spray the fiber with a very light coat of adheasive and lay the speaker cloth on top of it. Then use a sharp object like a hat pin and put in the holes needed. Us a little white glue to stablelize the holes let it dry and trim off the excess cloth and your good to go. I usually trim the fiber to the size of the board and pull the cloth around and glue it to the back side of the board. I like this method because you can get cloth with lines in it and they are straight as an arrow. Plus it gives the cloth a little depth that fills in aroung the outside grill. Looks GREAT. Good Luck George.

2/3/2008 4:28:03 PMMarv Nuce

Jon,
Here is an idea that I haven't tried on grille cloth, but used in many other areas with success. Its called "Heat n Bond", 18 inches wide, comes in a roll of different lengths, has a paper backing. Using an iron at specified temp, and follow instructions to iron it onto the grille cloth BACKING BOARD ONLY. Obviously the speaker hole will not be covered. After cooling, peel off the paper and iron on the grille cloth, stretching and shaping as needed to maintain appearance. I usually iron out the wrinkles/fold lines prior to installation. Don't use the steam mode. I found it to be semi permanent, because the cloth can be peeled off with a little help from an iron, but make sure you have excess to go around the back side for more permanent attachment with staples. Hope this helps.

marv

:Hi Jon,
:I'm going to throw my two cents in on this. I had a lot of trouble getting the cloth to come out just right and getting it straight so I came up with a really good method to my madness. I went to the local fabric shop in Walmart and picked up a sheet of white flat fiber material. Make sure you can blow through it with ease so it doesn't interfer with the sound. It is like a cotton fiber mix that is 1/8" thick. I do a light coat of adheasive on the board and stick the fiber to it. Then I spray the fiber with a very light coat of adheasive and lay the speaker cloth on top of it. Then use a sharp object like a hat pin and put in the holes needed. Us a little white glue to stablelize the holes let it dry and trim off the excess cloth and your good to go. I usually trim the fiber to the size of the board and pull the cloth around and glue it to the back side of the board. I like this method because you can get cloth with lines in it and they are straight as an arrow. Plus it gives the cloth a little depth that fills in aroung the outside grill. Looks GREAT. Good Luck George.

2/3/2008 4:21:16 PMplanigan

:Hello All,
:Any of you Wizards know of a trick to take out sags in grill cloth? Just finished a long restoration of a philco mod. 50(in a mod.51 cabinet) and ended up with loose grill cloth. I used up all I had of the correct pattern and used spray adhesive to apply it to the backing board.I had heard of some type of liquid that was used in model airplane construction thay would tighten up the cloth/paper wing material. Was wondering if this could be used.
:Thanks,
:Jon.

Jon, the cloth/paper used on model airplanes is "shrinkable". That is you moisten it and then stretch and glue. As the cloth/paper dries it shrinks drum tight. In you case, unless the fabric is cotton or wool, it won't shrink. If it is cotton or wool, try moistening it and press into place. If synthetic, you may have to pull it off and try again. I left mine with the small sag, I got to fustrated. PL

2/3/2008 4:50:08 PMMarv Nuce

Jon,
One other item I failed to mention is "Heat n Bond" is a paper backed iron on glue, and by applying the grille cloth from its front (visible) side to the back board, you're always viewing the final placement vs what you hope for when stretching around back and stapling. The glue is colorless, and shouldn't show through the material. Be cautious with original old grille cloth, because most were cotton, and will shrink if dampened then dried. The other suggestion using water may work to shrink it, but the water based glue may also be softened, or the stresses on the material grain may affect the shrink direction, so the outcome can be unpredictable.

marv

2/3/2008 6:58:18 PMJon

:Jon,
:One other item I failed to mention is "Heat n Bond" is a paper backed iron on glue, and by applying the grille cloth from its front (visible) side to the back board, you're always viewing the final placement vs what you hope for when stretching around back and stapling. The glue is colorless, and shouldn't show through the material. Be cautious with original old grille cloth, because most were cotton, and will shrink if dampened then dried. The other suggestion using water may work to shrink it, but the water based glue may also be softened, or the stresses on the material grain may affect the shrink direction, so the outcome can be unpredictable.
:
:marv

I knew you guys would come through. Many thanks for the suggestions-I printed these off and is going into my "tricks" file
Jon.
:
::Hello All,
::Any of you Wizards know of a trick to take out sags in grill cloth? Just finished a long restoration of a philco mod. 50(in a mod.51 cabinet) and ended up with loose grill cloth. I used up all I had of the correct pattern and used spray adhesive to apply it to the backing board.I had heard of some type of liquid that was used in model airplane construction thay would tighten up the cloth/paper wing material. Was wondering if this could be used.
::Thanks,
::Jon.

2/3/2008 8:03:43 PMThomas Dermody

If the staples method won't work, use scrap wood and clamps to clamp the ends of the cloth while it dries. Be very careful to only use enough glue to hold the cloth. Excess WILL squeeze through the cloth.

In small radios where the cloth is held to a cardboard baffle, if you can, stretch the cloth over the cardboard and clamp it. If the cardboard flexes (especially old brittle carboard....if you don't want to replace it), glue the cloth in place stretched out well. Place the assembly into the radio. Work out any wrinkles. Place strips of 1 inch thick wood at the top and the bottom of the baffle, or where appropriate. Place strips of wood, or, better yet, a board of ample size (though a board covering the speaker grill won't allow for adjustments) over the front of the radio for protection. Use very long and deep clamps to clamp the strips of wood on the inside. These measures are somewhat extreme. Usually they aren't necessary.

To prevent holes and sags in the speaker cloth, use the portable radio method--place window screen behind the cloth.