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Question for the pros, nothing to do with wood:
Research leads me to believe there are specific adhesive products for securing two pieces of concrete together. I made the rookie move of pouring a fencepost tube in two batches and that spot has separated - pretty cleanly and horizontally - leaving me with one end of a fence that waves in the breeze.
What is capable of making these two permanently one again?
Are you thinking you can glue the two pieces together with an injected epoxy?Quote:
Originally Posted by oftpiste
Way simpler to just pull out the old post and set a new one correctly.
By the time you fuck around with finding the kit, drilling and injecting you could have just gone to Home Depot and bought a couple bags of fast set concrete and a 4x4 and be time and money ahead.
Quote:
Originally Posted by DJSapp
I'm in the same boat, I have some rough sawn black walnut that my uncle gave me (he has a saw mill). I started cutting it down in preparation to build a pair of nightstands but put it on hold due to the fact that some of the slabs are big enough to get the entire tops out of a single piece. Unfortunately, my planer will only handle up to 10" wide pieces. I've called a couple small local furniture makers based on referrals to try to find someone who will flatten the slabs for me, but everyone is so busy I can't get a call back. I don't blame them. I wouldn't want to mess around with it either.Quote:
Originally Posted by I Skied Bandini Mountain
Before anything else: your backfill compaction around your tube is probably lacking as your post concrete is encased in a tube. Get some sand or small gravel and fill outside of the tube. Wiggle the post and flood some sand/gravel into the joint (hose + mound of stuff and make it flow into the gap). The reason I say this is assuming your post goes 24"+ into the concrete, a cold joint in the concrete would be at the very bottom allowing it to rock. You'd still have 24" of concrete encased post in the ground that is able to wiggle. The cold joint may not be your problem. Try the easy thing first.Quote:
Originally Posted by oftpiste
For concrete fixing - 4 options here:
1. You could drill holes to the cold joint and directly inject some Set-22 and hope. Concrete epoxy isn't really designed to glue two separate pieces of unreinforced concrete together. This will take most of your Saturday and maybe has a 40% chance of success.
2. Assuming you have a long enough rotohammer bit to get well past the cold joint, you could rotohammer 4 holes through the joint, epoxy the holes short of the cold joint and stab a piece of 1/2" all thread through from the top. Wrap the all thread in some butcher paper above the cold joint so that side doesn't bond to the concrete. Once the epoxy cures, put a big washer and nut on the top of the concrete and tighten down. 75% chance of success if executed well and that the bottom concrete is sound enough to hold the all thread.
https://www.homedepot.com/p/Simpson-...ET22/100374875
3. Or you could get a sledge and/or rotohammer, bust out the loose stuff, vacuum any small loose stuff out of the joint, rotohammer a couple of holes in for some expansion anchors join the old and new, and then pour a fresh bag or two of concrete in there and be done by lunch with a 95% chance of success. If you wanted to go pro, you'd epoxy in some rebar dowels to join the old and new, but expansion anchors should be good enough for a fence. Longer is better for the expansion anchors, as you are using it as a dowel and want half in the old concrete, half or more in the new.
https://www.homedepot.com/p/Simpson-...5120/205302275
4. Demo the concrete and replace it. Dumb, simple, cheapest of all options by far, 100% success rate and if you're leaning toward option 3, you may realize it isn't much more effort to get the last bit of concrete out, depending on where the cold joint is.
Frankly I'd just roll with option 4. Concrete repair work is best left to structural concrete that you believe was actually properly consolidated and is generally sound. Fencepost concrete is generally not very sound and would break up further upon repair attempts.
Thanks for the extensive thoughts on concrete repair. Seriously good beta.
This is a clean break and above ground, tube has been removed from the concrete column. No injection or drilling necessary to access the break as I can lift the top broken chunk up off the lower one with the fence attached to allow plenty of space to squirt or smear some kind of adhesive in there. IF (a big 'if' I know....) there is an adhesive that will reconnect these two chunks decently it'd be WAY easier than busting it all out and starting over.
It doesn't have to withstand a while lot of movement, just occasional wind buffets which only happen a couple times a year with enough velocity to make me nervous about it. No one's hanging on it, the fence isn't super heavy and supported by another correct post 8' away.
Ah, that makes more sense. New ideas:Quote:
Originally Posted by oftpiste
1. Stick with the original option #2, or depending on the depth from the top to the crack, just rotohammer holes in and install an expansion anchor.
2. Roughen up the edges of the column and put a larger form around the existing column. Pour a larger column and encapsulate the old. If you want to go crazy, drill in some rebar dowels to the existing to bond the new to the old.
Not sure if it would work forever and it ain't cheaper but this is what I'd use in a pinch....you would also need access or rental of the gun. Get the battery powered one as this stuff is thicccccQuote:
Originally Posted by oftpiste
https://www.hilti.com/c/CLS_FASTENER..._7135/r8298802
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Doing the back side first for practice isn't a bad idea. In general though, I do what the old time cabinet makers did--before power jointers and planers and wide belt sanders. I just flatten and smooth the surfaces that show or where I need to cut joints. If I had a wide belt sander I could run the back side through that but since I'm doing it with hand planes only the show sides get smoothed. And the non show parts of my cabinets--like the bottom of a case that will sit on the floor-- are birch plywood with only the front edge being nice hardwood. Look inside a colonial era piece of furniture and you'll see a lot of rough surfaces. If I were selling my work I would smooth everything but as it is no one will ever know but me. (I'm sure my kids won't want any of it.)Quote:
Originally Posted by DJSapp
(Similar thinking in house construction. Colonial houses were post and beam because they had big trees and no easy way to turn them into skinny pieces of lumber. We have run out of big trees and turning a log into 2x4's is easy for us so we stick build unless we're rich.)
Hand planes--a scrub plane used diagonally and then a jointer plane longitudinally. My scrub plane is a cheap Stanley jack plane with the blade edge ground to a curve and the cap iron set way back from the blade edge. It's surprisingly quick. A good jointer plane is not cheap and a lot of work to use.Quote:
Originally Posted by Buke
Thanks again DJ!
Option 2 (pouring new around old) was in the works until it started to seem there might be appropriate adhesive products. The only issue would be aesthetic, as one side of the column is at the edge of the sidewalk, so the new and larger column would not be centered around the existing one. On one side would be a very thin new pour, though the rest of it would probably hold.
I'm still probably leaning toward at least trying the adhesive-glue-them-together option at this point. If it failed again I could always start over. Just seems like it's worth a try if I can find a product.
I've seen concrete epoxy advertised, and a few other rare things. Attempts to contact the local masonry supply for advice have so far not been answered.
https://www.amazon.com/Powers-AC100-...13105393&psc=1
https://www.grainger.com/product/53T...B&gclsrc=aw.ds
https://www.emisupply.com/catalog/si...B#.YG5AYi2cb4M
Quote:
Originally Posted by DJSapp
I wouldn't go the glue it together route. That stuff is $30 a tube, plus the double barreled gun (rent the electric gun if you can find it, the mixing nozzle is a bear), injecting is a bitch, and I'd guess you have a 40% chance of success because it isn't designed to do what you want it to do on this scale.
Demo is the right way here and will be easier before you put a bunch of high strength epoxy in the works.
I've poured and repaired enough structural concrete to know the easy path when I see it. But you do you.
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My $0.02, remove and replace is for sure the right solution. What do they say, "fix it right the first time", or something like that.Quote:
Originally Posted by oftpiste
With that said, if you want to throw a little money at a marginal simple fix to see if it will work "good enough for who it's for" then any of the epoxies that you've listed will probably work. The Hilti HIT-HY-270 that ZBO mentioned is the top notch pro option, although that formula is intended for masonry not concrete. The Hilti HIT-RE 500 is the top of the line option for concrete. The thing is, all of these epoxies are intended to bond threaded steel rod or rebar into a drilled hole. None of them are intended to bond concrete to concrete. I wonder if a simple tube of construction adhesive wouldn't work just as well. Then you're only out $10 if it doesn't work out.
If you're serious about epoxying it together then the best option is to drill a few holes in both the top and bottom pieces of concrete and embed a short piece of rebar or threaded rod to bridge the cold joint. These short pieces of steel would be epoxied in place using the Hilti Re-500 or similar epoxy.
Again, I'd be surprised if it wasn't a much better solution to just dig it out and replace it.
I keep thinking this. PL Premium (polyurethane) is some INSANE shit, and if you've ever tried to remove a piece of wood glued to concrete with it, the most likely outcome is that you will pull out a huge chunk of concrete. A tube of that liberally applied might just provide enough bonding to work.Quote:
Originally Posted by Buke
I did not build this board but I need help from the woodworkers in this thread. What product should I use to fill those two 1/8”-1/4” cracks in the middle? I need this thing to be food safe and sanitary...
Attachment 370976
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Theoretically there is food safe epoxy but I still wouldn't use it on a cutting board. I would just convert that thing to a charcuterie board and start over with a new cutting board.
Isn't one of the titebond products food safe? Mix sawdust and tb then cram it in yer crack?
There’s at least two other unsanitary cracks in that piece, based on the photo. Buy clear bar & table top epoxy and fill away.
You could try to soak in a bleach solution (alt: hydrogen peroxide)
Normally you're supposed to scrub it in to keep it stable/flat, but you're trying to get the gunk out or at least kill it
short soak?
(then plane lightly?)
then re-season with a food safe penetrating sealer
Quote:
Because wooden cutting board should not be placed in the dishwasher, bleach is the preferred method of cleaning wooden cutting boards. Additionally, fully disinfecting a wooden cutting board is particularly important because wooden cutting boards build up scratches and grooves over time that can house bacteria.However, you want to use a slightly different method than what we outlined above. Soaking a wooden cutting board can cause it to warp. Instead of soaking in the bleach mixture, apply the solution to the board with a bristle brush, being sure to scrub into all the grooves on the board. Let it sit for about two minutes and then rinse and dry. This will allow you to disinfect without ruining your cutting board.
https://www.woodcuttingboardstore.co...ng%20them%20up.
The way that has been built (end grain and cross grain joints) I see potential cracks developing done the line, regardless of any filler used.Quote:
Originally Posted by nickwm21
I like colored epoxy--usually black-- for filling cracks that can't be hidden, but epoxy will ruin your knives. So will glue and sawdust. Crashtestdummy is right. The way that thing is built the wood can't expand and contract with changes in moisture content. If you fill the cracks, the wood will be forced to crack somewhere else.
Titebond 2 and 3 are both food safe for indirect food contact (i.e. cutting boards). I'd probably go with 3 for this for the longer set time. Mix up a bunch of sawdust (same wood species) with the titebond, pool it over the cracks, and put your shop vac on the other side of the board to suck the glue into the joint (assuming the cracks go through the board). Scrape off the excess after it starts to harden a bit, but before it gets really hard.
Recoat with your cutting board poison of choice.
Yes, that board will have movement issues and will likely crack again. Maybe you'll get a few seasons, maybe not. But this will get it back to usable.
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Reminder--glue is harder than wood and dulls edge tools. In our community shop there was a cutting board class--gluing up multicolored strips of different woods--and people were letting the glue harden and then running the boards through the planer. They were not just dulling planer blades, they were breaking them. If you want to try to fill the cracks I suppose you could try to keep the filler a little below the wood so the knife wouldn't contact it.
I keep a chisel just for removing excess glue, and I remove the excess after the glue has set but not hardened--about 2 hours for Titebonds.
I wouldn't be worried about food safety--once glue is cured it's pretty damn inert, especially considering the short time the food is in contact. (Oil finishes are another story--only mineral oil IMO, or go bare.)
https://osmocolorusa.com/product/topoil-high-solid/Quote:
Originally Posted by nickwm21
The Safety Data Sheet doesn't sound that encouraging. https://ardec.ca/media/catalog/msds/...opoil-osmo.pdfQuote:
Originally Posted by snoqpass
Even if it is food safe it doesn't sound like a product you would use to fill a crack. Sounds like a surface treatment--like mineral oil.
I've never cleaned a wood cutting board in anything other than soapy dish water, am I gonna die? For real, I'd have maybe just mixed sawdust and wood glue into that, but, more than likely, just ignored it for a few years. Oops?
I’ve actually used this product on countertops I built enlighten me some moreQuote:
Originally Posted by old goat