I want to use blop on my window sashes but I have spots here and there that need repair. The instructions on the epoxy says don't use turpentine based coatings so I'm wondering if epoxy is compatible with blop.
If I treat with blop and wipe off the excess I could let it dry for a couple of weeks if needed. Would using epoxy be questionable?
Can sarco putty be used to make repairs instead of epoxy?
Blop and epoxy
Blop and epoxy
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phil
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Re: Blop and epoxy
best to use a waterproof glue and a clamp for that. you could choose epoxy or other glues. no epoxy isnt' compatible with blop. If you want you can use epoxy but do that before you apply blop because otherwise the epoxy wont bond and any other coating will fill the fibers and prevent a bond. . You want the epoxy to go into the fibers to get a good bond. You could clean out the crack with a flat thin tool.
I'd mask off the area surrounding the crack and surround the dents with tape as well. so the ooze out doesnt' get on the piece when you clamp it up. When you apply the blop after it will not soak in to where epoxy is on the surface and you will then see a lighter area where the epoxy is.
if you apply epoxy it's a one shot deal you will never separate it again. if it's a valuable antique its best to use hide glue as that can be disassembled with steam but I wouldn't use that on a window because of moisture.
never mix epoxy with other things, except maybe powdered pigments. It dries by the combination of the two ingredients through a chemical reaction, not by offgassing. if you contaminate the epoxy with things like paint or other greasy substances it won't harden. Don't apply epoxy over paint or blop , it wont' stick.
if you want to fill a large gap you can combine wood shavings with one part, then mix in the other component and that will be stronger than just epoxy and also replicate the look of wood. You can also cut wood blocks or wedges so the epoxy occupies less space, the strength is in the bond not the epoxy itself. less epoxy within the repair is better. That said epoxy can fill some gaps. If you try to fill gaps with carpenters glue the bond won't have any strength but epoxy is better this way.
epoxy wont have light blocking abilities so if it sits in the sun the UV will eventually deteriorate the bond. If you paint it then that will block the light.
epoxy is not porous like wood. wood expands and contracts as it absorbs and gives off water. Epoxy does not. Its basicaly like a chunk of plastic. so keep repair areas small to prevent the natural wood movement from breaking the bond or from water creeping between the wood and the epoxy through capillary action.
if you can it's best to sand the wood and roughen up the surface and clamp to get the epoxy right down into the wood fibers. you might not need to separate the joint but clean it as best you can.
I'd put tape everywhere but on the crack , then put the epoxy in the crack with a thin blade, then clamp then pull the tape and clean up but try not to wipe theepoxy all over. if you get drips leave it , when dry you can remove any excess with sanding.
it takes usually overnight to set, and a week or so to cure and be hard enough to sand, that will vary wiht the type of epoxy and the temperature.
dont leave the masking tape on pas the stage where the epoxy turns into a plastic state or it'll be hard to get the tape off.
yes you can fill cracks with sarco and paint or use wood filler but that wont provide strength. it may help keep water out of the cracks in the wood and prevent deterioration.
some wood filler is water based, dont use that on windows but its ok on interior trim. the type that is solvent based dries faster so you have to use up the amount you take out fairly quickly. the water based stuff can be thinned with water if you use it for longer periods and keep your batch open. if it gets wet, the water based stuff will loosen up. You might want it to loosen if it is the floor and you have a spill as this can prevent the floor from heaving up. If you put it on exterior surfaces it wont last. even under paint the moisture will get to it.
the blop is good but do the epoxy repair first. dont break the window by clamping it with the window in the frame , remove it first, then you might need to chisel a little so the glass can fit loosely if the frame has shrunk. mask your litle indents and I'd use a bit of wood dust in the epoxy where you fill the indents. I wouldn't put wood dust in the crack as that will prevent the parts from pulling up tight. if you go ahead and use blop after the epoxy is there, the blop cant soak into the epoxy as it is non porous, it wont hurt anything it just will not soak in.
any gap bigger than a credit card wil fit can be filled with wood wedges and epoxy then you wont see a line of epoxy, but in that case you want the joint to pull into place so you dotn need to fill the gap. if there is a gap after you clamp it then you can always do more. If you pout epoxy over other epoxy sand it to break the glaze. the epoxy wont knit chemically once cured so it is like a separate layer.
you cna use fiberglass cloth with epoxy but you wont want to use that there. in some applications the cloth adds a lot of strength. the epoxy , in itself is not particularly strong. the strength is in it's ability to attach or bond things.
epoxy will not stick at all to most plastics. if you want a shiny flat surface one trick is to use plastic as a form and the epoxy will take on the smooth finish of the plastic.
as an example, If you had a corner chunk missing you could make a dam out of a piece of wood that is inside a baggie. then the epoxy wont stick to your form. the form will contain the epoxy until it hardens and turns from liquid to solid.
it looks like it isnt' a window but a wood panel. when such a panel is constructed there needs to be room for shrinkage so the panel should have the ability to float in the groove a little. It could be that due to shrinkage, the panel might prevent clamping up properly. i'd do a dry calamp up first to test and see if the joint will get bound up by the panel if you dont intend to remove the panel. If the maker failed to leave some wiggle room for the panel it might be pushing the frame apart as the rails and styles shrink with age. you may see this happen for example if you set a door outside in the weather where it sees more expansion and contraction.
modern cabinetmakers sometimes use little round rubber balls to place in the panel groove. this allows necessary movement with humidity changes, but also keeps the panel from shifting around too much.
traditionally panels were made from strips of wood, when plywood was invented then it became more common as a panel.
plywood is more dimensionally stable than strips of wood glued into a panel. with plywood, the fibers run both directions between the layers. old plywood was generally made from thicker layers and better wood than modern plywood but there are different qualities available. marine grade plywood can resist water a lot better .
although wood changes in both directions , generally it shrinks and grows more across the grain with age. so if it has a panel that is made from wood strips with the grain running vertically you will see more expansion and contraction from side to side and only slight changes in the vertical dimension. If the panel gets wet the wood will expand and it may push the frame apart at the corner joints. over time wood tends to shrink but it always moves somewhat as the humidity changes. its easy to forget that and create things that self destruct with humidity changes.
in your pic I can see the grain in the panel is vertical that means if it gets wet the panel will tend to grow horizantally. if it got wet then it might have pushed the joint apart from the panel expanding. when wood grows from humidity expansion it has tremendous force much like how freezing water expansion can break things , so can this.
for that reason it might be possible to glue that up perfectly well and then see it break again perhaps on the opposite side, if the panel is trapped. It could also be that that panel was put outside leaning against the back of the barn for a year or two, and it may never again see such drastic changes.
wood also does see some shrinkage with age so a part that is 2 feet long may see some change in length. so the outer parts could have shrunk a little over time too.
on way to tell the difference of a true antique from a good copy is to look for signs of wood shrinkage within a piece. often if you look carefully at antiques you will see minor changes due to age and the wood drying up. and those telltale signs usually would not be replicated in a fake. that's also a reason to use wood parts from an old door to make a window, because the wood is old and more stable and also probably old growth tight grained lumber.
I'd mask off the area surrounding the crack and surround the dents with tape as well. so the ooze out doesnt' get on the piece when you clamp it up. When you apply the blop after it will not soak in to where epoxy is on the surface and you will then see a lighter area where the epoxy is.
if you apply epoxy it's a one shot deal you will never separate it again. if it's a valuable antique its best to use hide glue as that can be disassembled with steam but I wouldn't use that on a window because of moisture.
never mix epoxy with other things, except maybe powdered pigments. It dries by the combination of the two ingredients through a chemical reaction, not by offgassing. if you contaminate the epoxy with things like paint or other greasy substances it won't harden. Don't apply epoxy over paint or blop , it wont' stick.
if you want to fill a large gap you can combine wood shavings with one part, then mix in the other component and that will be stronger than just epoxy and also replicate the look of wood. You can also cut wood blocks or wedges so the epoxy occupies less space, the strength is in the bond not the epoxy itself. less epoxy within the repair is better. That said epoxy can fill some gaps. If you try to fill gaps with carpenters glue the bond won't have any strength but epoxy is better this way.
epoxy wont have light blocking abilities so if it sits in the sun the UV will eventually deteriorate the bond. If you paint it then that will block the light.
epoxy is not porous like wood. wood expands and contracts as it absorbs and gives off water. Epoxy does not. Its basicaly like a chunk of plastic. so keep repair areas small to prevent the natural wood movement from breaking the bond or from water creeping between the wood and the epoxy through capillary action.
if you can it's best to sand the wood and roughen up the surface and clamp to get the epoxy right down into the wood fibers. you might not need to separate the joint but clean it as best you can.
I'd put tape everywhere but on the crack , then put the epoxy in the crack with a thin blade, then clamp then pull the tape and clean up but try not to wipe theepoxy all over. if you get drips leave it , when dry you can remove any excess with sanding.
it takes usually overnight to set, and a week or so to cure and be hard enough to sand, that will vary wiht the type of epoxy and the temperature.
dont leave the masking tape on pas the stage where the epoxy turns into a plastic state or it'll be hard to get the tape off.
yes you can fill cracks with sarco and paint or use wood filler but that wont provide strength. it may help keep water out of the cracks in the wood and prevent deterioration.
some wood filler is water based, dont use that on windows but its ok on interior trim. the type that is solvent based dries faster so you have to use up the amount you take out fairly quickly. the water based stuff can be thinned with water if you use it for longer periods and keep your batch open. if it gets wet, the water based stuff will loosen up. You might want it to loosen if it is the floor and you have a spill as this can prevent the floor from heaving up. If you put it on exterior surfaces it wont last. even under paint the moisture will get to it.
the blop is good but do the epoxy repair first. dont break the window by clamping it with the window in the frame , remove it first, then you might need to chisel a little so the glass can fit loosely if the frame has shrunk. mask your litle indents and I'd use a bit of wood dust in the epoxy where you fill the indents. I wouldn't put wood dust in the crack as that will prevent the parts from pulling up tight. if you go ahead and use blop after the epoxy is there, the blop cant soak into the epoxy as it is non porous, it wont hurt anything it just will not soak in.
any gap bigger than a credit card wil fit can be filled with wood wedges and epoxy then you wont see a line of epoxy, but in that case you want the joint to pull into place so you dotn need to fill the gap. if there is a gap after you clamp it then you can always do more. If you pout epoxy over other epoxy sand it to break the glaze. the epoxy wont knit chemically once cured so it is like a separate layer.
you cna use fiberglass cloth with epoxy but you wont want to use that there. in some applications the cloth adds a lot of strength. the epoxy , in itself is not particularly strong. the strength is in it's ability to attach or bond things.
epoxy will not stick at all to most plastics. if you want a shiny flat surface one trick is to use plastic as a form and the epoxy will take on the smooth finish of the plastic.
as an example, If you had a corner chunk missing you could make a dam out of a piece of wood that is inside a baggie. then the epoxy wont stick to your form. the form will contain the epoxy until it hardens and turns from liquid to solid.
it looks like it isnt' a window but a wood panel. when such a panel is constructed there needs to be room for shrinkage so the panel should have the ability to float in the groove a little. It could be that due to shrinkage, the panel might prevent clamping up properly. i'd do a dry calamp up first to test and see if the joint will get bound up by the panel if you dont intend to remove the panel. If the maker failed to leave some wiggle room for the panel it might be pushing the frame apart as the rails and styles shrink with age. you may see this happen for example if you set a door outside in the weather where it sees more expansion and contraction.
modern cabinetmakers sometimes use little round rubber balls to place in the panel groove. this allows necessary movement with humidity changes, but also keeps the panel from shifting around too much.
traditionally panels were made from strips of wood, when plywood was invented then it became more common as a panel.
plywood is more dimensionally stable than strips of wood glued into a panel. with plywood, the fibers run both directions between the layers. old plywood was generally made from thicker layers and better wood than modern plywood but there are different qualities available. marine grade plywood can resist water a lot better .
although wood changes in both directions , generally it shrinks and grows more across the grain with age. so if it has a panel that is made from wood strips with the grain running vertically you will see more expansion and contraction from side to side and only slight changes in the vertical dimension. If the panel gets wet the wood will expand and it may push the frame apart at the corner joints. over time wood tends to shrink but it always moves somewhat as the humidity changes. its easy to forget that and create things that self destruct with humidity changes.
in your pic I can see the grain in the panel is vertical that means if it gets wet the panel will tend to grow horizantally. if it got wet then it might have pushed the joint apart from the panel expanding. when wood grows from humidity expansion it has tremendous force much like how freezing water expansion can break things , so can this.
for that reason it might be possible to glue that up perfectly well and then see it break again perhaps on the opposite side, if the panel is trapped. It could also be that that panel was put outside leaning against the back of the barn for a year or two, and it may never again see such drastic changes.
wood also does see some shrinkage with age so a part that is 2 feet long may see some change in length. so the outer parts could have shrunk a little over time too.
on way to tell the difference of a true antique from a good copy is to look for signs of wood shrinkage within a piece. often if you look carefully at antiques you will see minor changes due to age and the wood drying up. and those telltale signs usually would not be replicated in a fake. that's also a reason to use wood parts from an old door to make a window, because the wood is old and more stable and also probably old growth tight grained lumber.