Newbie stuck with a red gum slab

[davep]

Hi folks,

Have been a reader of this forum for sometime, but now I've become a user.

We have a red gum slab which is 265cm long by 70cm wide by 5cm thick. It has a live edge on both sides. Our plan is for it to go on our bar.

We were wrongly advised by our paint shop to use Northane Clear Gloss which is a polyurethane to fill our cracks and holes. Others had told us that epoxy resin was the answer.

With first mixing the product we felt it was too liquidy, rang the paint shop who said it will be fine. With our application it sank into the wood. Rang the paint shop again about this, the answer allow the 1st coat to dry, the second coat will start to build up. 2<SUP>nd</SUP> coat again generally soaked in. We rang Norglass who told it is absolutely the wrong product, we should have been sold their Epoxy Laminating Resin.
:doh:
The picture taken is with the polyurethane on it, all the dark bits. We are worried about how it will now finish. Further enquiries about what to do lead me to think that the job is too hard for us. My wife and I have been doing heaps of renovation work, but this red gum slab is beyond us. My question is, would someone like to take this job on? We'd want an approx. price up front. I have several more pictures of the slab which I could email. We want the slab finished off with a matte finish. I really hope someone would like to do this.:) We live in Wahroonga.

Best regards, Dave.

[Tonyz]

South Oz is a bit to far away but Iam sure someone closer will come to the aid of the party.

Dont worry thougfh all is not lost and with some gentle coaching we'll get you doing the job yourself and being stuffed proud of it.

[watson]

I agree with Tonto,
I can't help you with info, but other members of the forum will be able to set you on the right track....and then it'll be your own work....and your bar will then be your own thing.
Relax and incoming stuff will solve the problem!

[davep]

Thanks guys, where we see the difficulty is how to get the epoxy onto the live edges. We've been told to use white plastic cutting boards as they do not stick to the epoxy. Heat the boards to fit the curve of the edges. This is what sounds just too hard. Then questions like what is the best epoxy product for our job and how do we go about applying it? Is the existing polyurethane going to create problems? I guess many more.

In our situation to avoid more grief, paying $$ is an easy option.

Thanks greatly, Dave.

[RufflyRustic]

Dave, I think the red gum slab is VERY salvageable and I'm sure you will be able to do the work yourself, without a problem.

The difference between the poly and the expoxy, (imho) is that the epoxy will stop any further cracking.

My suggestion is to get a scrap piece of timber with a crack or two in it, put the poly on it the same way as you did for the slab. Then when it's dry, lightly sand with 80 grit, clean away the dust and apply a coat of expoxy. This test is to see how the two products go together eg does the expoxy never set? etc etc

For the slab, give the top a good sand down all over to keep it even, 80 grit's a good start and then maybe 120 and 180.

Are you intending on using the epoxy to cover the whole slab, or just fill in the cracks and such?

I've found the West System epoxy doesn't stick to Tiger Baking paper and another member on the board uses plasticine as a stopper when epoxying cracks and holes in turning blanks.

Hoping this helps and gives you an idea that it is salvagable and you are able to do this job yourself.

Cheers
Wendy

[BUNTA]

If the resin you have put in is already dry... ? buy some glass coat from bunnings (i am not affiliated with this company in any way ..bla bla bla) it is a two part resin. for the live edges i use a wire brush wheel fitted to a angle grinder to clean off any remaining bark then sand both top & bottom surfaces of the slab so tape will stick.
position the slab so that the resin can be poured strait in & any parts that will allow the resin to drain away can be blocked off using duct tape ( the wide gray tape ).
it takes about a day to be touch dry & after 2 days should be fine for sanding .
hope this helps.

[BobL]

Thanks guys, where we see the difficulty is how to get the epoxy onto the live edges.

By the look of the bits of tape stuck to the sides of the slab, instead of "onto" I think you mean "into the cracks on the natural edges"?

If so, it is impossible to get the epoxy to stay in the cracks unless the surface you are working on is facing directly upwards. Stick a gaffer tape sleeve all the way around the outside of the upward facing surface so that the epoxy doesn't leak out of any side cracks. if it's a cool or cold day heat the timber up with a hot air gun till it is noticeably warm

Then use a syringe to gently squirt drop epoxy into the cracks till it slightly oozes out of the cracks. If you don't have a syringe a large splinter of wood will do as a dipping/application strip. For very fine cracks use a disposable paintbrush. If the epoxy pools unecessarily in any hollows you have to suck/wipe out the excess. You may need to apply the epoxy several times to fill all the cracks. In some cases it has taken 6 applications fo fill the cracks. Once the cracks are full and set, move onto the next surface. At some stage you should paint all the natural edges with epoxy

Then sand back the flat surfaces and finish with your preference.

For the natural edges bush use gently with a very fine/soft wire brush. A good example is the very fine wire brushes available for Dremel tools. These will polish the epoxy/timber on the natural edge to a nice soft sheen.

It is time consuming work and you just need to be paitent, but it's well worth it in the long run

Cheers

[salty72]

we have the ability to suface anything upto 1200mm in width and can probable fix your problem for you ... HOWEVER we are 130Km North of SYDNEY (Raymond Terrace) -this might be a problem,

If not give us a ring 043 TURNING (043 887 6464)

[Bodgy]

This is not such a big problem. Best to have a look.

I'm at Turramurra so PM me and I'll try and get over one evening. Strongly suggest you don't do anything else to the slab yet.

[davep]

Thanks very very much to everyone for your words of encouragement. Rufflyrustic we used to live in Toowoomba, both went to school there, 1st jobs and first house.

I'm taking up Bodgy's offer for him to have a look.
We hope to keep the live edges, the epoxy is to fill the cracks on them and also on the flat top surface. Several holes to be done as well. Then we just want a matte finish of some type that is fairly resistant to spills, etc, as a bar top needs to be.

Many thanks to all again, this is a top forum. Dave & Di.

[RufflyRustic]

Good on ya Bodgy!! :2tsup:

Don't worry Dave & Di, Toowoomba hasn't changed that much :rolleyes:


Also, check out the Slab Hut's website (http://www.slabhut.com.au/). It's a small site, but interesting to see.

cheers
Wendy

[davep]

Also, check out the Slab Hut's website (http://www.slabhut.com.au/).

Thanks Wendy, I particularly like the Slab Hut's bar stools.

Kindest regards Dave.

[davep]

Hi folks,

We've made no further progress with our red gum slab. Basically indecision is our problem.:no:

The first pic shows the polyurethane on the top.
How do we remove this? With a cabinet scraper or a citrus chemical remover? Or any other ideas?

The second pic shows an area that we'd like to fill with epoxy.
Can we build this up with gaffer tape or baking paper so that the epoxy ends up being equal to the top, but at the same time forming a wall on the side?

Finally is polyurethane okay to finish the live edge or should we use epoxy? We are after a matte finish.

Thanks greatly, Dave.

[davep]

Can we use blu tac to dam up and make walls to hold the epoxy?

Thanks, Dave.

[MacS]

I think that if you used the "epoxy putty sticks" you could do the job yourself if you wanted too.

You won''t need any "daming" as this putty will not run, sag, or shrink. it is easy to apply, and with a plastic credit card you can scrape off the excess, or you could shape or mold it any way you wish. It is hard in less then one hour, and is ready for finishing.

I mentioned this before here on the forum, do a fast "search" there is a photo of what it looks like. I think I may have one showing the steps of how is done.

I will go look for it, and post it, if I find it.

MacS

[MacS]

Here are the basic steps to working the epoxy putty sticks.

1- Cut off a piece of the epoxy stick. (note the resin and the cataylst)
2- Knead the 2 part putty until there is only color, push the putty down into the defect.
3- Flatten the putty.
4- Scrape off the excess putty.
5- Sand the putty level to the surface.
6- Your ready for finishing.

I hope this helps.

These sticks are a great repair tool to have around the home or the shop. They will cure under water, and can be used on interior or exterior work.

Wow, it worked..

MacS

[astrid]

I think that the poly you put on will be well cured by now. sand it back on the top and see how it looks.
I would asume that the crack on the bark goes all the way along and you want to fill it with somthing clear but colour tinted not asolid colour putty.

epoxy stix are easily available here, my local mitre 10 stocks them, but for the amount of filling you have to do their not cost effective.

If you want to just fill the top holes with a flat filler, good old builders bog
(the white one not pink!) can be coloued up with powder colour that you get in small quantities from your art shop. ask the sales person ,who in the small art supplers is usually very knowlegable about which powders to buy to get the desired colour.

mix up a small amount of bog and stir in the colour. PRACTICE FIRST!!
as it goes hard very fast.

If you want a clear but colored filler use same technique with good old two pack araldite, as this is a glue it will stick to what youve already put in there, it will sink in the middle so make sure you over fill the cracks.
if it sinks again you simply fill over and this time it will stay level as the first fill has created a barrier.
on the edges use gaffa tape to make a dam wall, use your blue tack to seal the bottom edge or the filler will run out of the bits the tape cant seal.
Practise first.
when either filler is dry it can be sanded smooth.

if youve never done a lot of filling. get an old bit of timber with lots of holes and cracks and practice.
this is more a matter of learnig how the filler flows and how fast it drys rather than any skill needed to fill a hole!

have fun
Astrid

[MacS]

Is using Epoxy Putty Sticks cost effective, would they be worth using on this project.

Yes, I think so, because their cost would be a kot less then paying some one else to do the work and then charging you for their time, labor, and materials to do this job for you.

I don't know anything about builders bog, so I can not make a comparison other then this, the epoxy putty sticks already comes in different colors, kneading is needed, but you will always get the same color.

Curing is guaranteed, there is definitely no shrinkage, to retard the drying of the putty stick, use a little alcohol on a spatula this will help you shape putty on the edges.

You do not need any kind of tape or any dams, one fill is all you need as there is no shrinkage, becuse these putty sticks contain no solvents.

Another feature about using the putty sticks is you do not need to move the timbers position, as you can repair it in the same place it is in now.

No practice is needed if you just follow the simple directions on the epoxy putty sticks label.

[astrid]

its used by really good haut antique restorers to replace missing bits in parquetry, so its not a cowboy solution, you can colour it sand it drill it and put a finish over the top

astrid

[rsser]

... and steer clear of BluTak to stop liquid fillers. DAMHIKT!

[astrid]

sorry, just guess ing at the blue tac bit
but if your using tape to seal off bark its not going to seal the bottom of the damm wall
I hope you get what i'm talking about.
so how do you do this

astrid

[MacS]

Neither, are epoxy putty sticks used in cowboy situations.

As an example:
The conservators at the Smithsonin use these same sticks on all kinds of furniture restorations, they are also being used by the exterior conservator restorers to save exterior steps, doors, windows, and wood trim from further decay and aging.

Normally, all repairs must be reversible, epoxies are not reversible, but its better to save the treasures then let them decay away, so they finally were accepted to be used where and when no other material will work.

[rsser]

Let's not argue over it, MacS. There's always more than one way to skin a cat.

[astrid]

as bark is uneaven, how do you seal the bottom edge of the wall?
any ideas
astrid

[davep]

Exactly, sealing the bottom edge on the uneven bark is our biggest challenge, although getting the poly off is surely another.

Okay if blue tac is no good damming sections, what about plasticine, some say that is the way to go?

Can araldite be sanded down okay?

Do epoxy putty sticks offer a clear product, I'm thinking not?

Sorry for the questions but all the advise is very much appreciated, thanks Dave.

[astrid]

i was guessing that you wanted the gaps filled with somthing resemling the natural gum in red gum.
so use a clear filler like araldit or clear epoxy and tint it
i understand the prob with sealing the bottom of the wall
can anyone help?
maybe you could dribble wax in and use a hairdryer to melt it off?

astrid

[MacS]

Ern,

Yea, that's why I add my options and opinions to the forum.

Dave,

No, they do not come in a clear stick, when a clear is needed we normally use the clear epoxy filler, which is like the clear epoxy glue. They come in 5 minute and 12 hour units.

[astrid]

you can sand araldite, plasticene might be hard to remove.remember kids and carpets. try melting wax on the outside edge of the tape at the bottom of your wall you can melt this off when finished. do a practice run
astrid

[davep]

Thanks all, yes a test or two is the go. Have to test if the epoxy will adhere to the polyurethane that we should never have put on. I'd much prefer to get it all off. Our paint shop, who suggested the poly, is now suggesting we use a citrus foam stripper, so potent that you need to use special gloves with it. A$17 for the stripper, A$50 for the gloves.

[MacS]

I just looked up "builders bog," it is a 2 component polyester filler, similar to the "Bondo Body Filler," which I am very familar with, because it is a sister company to the company I worked for 30 years.

Epoxies and Polyesters both have pros and cons, in this case I woiuld used the epoxy over the polyester, because polyester can not handle stress, it will began to crack or fall out of the repair.

Polyesters comes in different color cataylst, builders bog comes with a white catalyist, they also make a red and blue catalyst, most auto body shops used the red cataylst. Polyester can also be colored with the dry colored fresno powders.

In some cases either the epoxy glue or the CA glue is used to attach any loose bark, this is the first step in the repair process.

[MacS]

Dave,

Yes, epoxy will adhere to polyurethane, it will also adhere to metal and glass. First wipe it with white spirits to clean it.

If you going to strip it, then get a pair of nitril gloves they are much cheaper then the neoprene heavy duty gloves.

[astrid]

we are still not getting any advise re the dam?
astrid

[astrid]

dave,
re dam
I know a guy that makes tables etc with bark edge
I'll ring him when I have a mo and ask how he does it.
I dont think you need worry about the poly, you,ve only put it in the surface cracks, right?
just sand it to surface, the araldite/clear epoxy will cover fill and stick and the final finish will go on top,
i'll get back asap
astrid

[MacS]

Modeling Clays, are commomly used to build dams.

Epoxy Putty, is also used when certain chemicals may effect the modeling clay.

[davep]

Hi gang, thanks greatly for all this info.

We'll get into the project shortly. I'm sure we'll have more questions as we go.

Thanks again Dave & Di.

[davep]

Hi folks,

Hope your x-mas break is going well.

We have steered away from doing anything to our bar top, but now finally at the stage that we now do need to finish it.

It's best we reckon to stay away from epoxy resin as we do want a matte finish once done. The idea of tinting Araldite appeals to us, but our big concern still is the Northane Clear Gloss polyurethane which is in all the cracks and also forms a border around the cracks, very noticable on the top. My pics on the first page show this.

Will Araldite stick to the polyurethane? Should we get rid of the polyurethane, if so with what? We'd hate to finish the whole thing to see bordered cracks all over this.
Would it take much sanding to get down through the surface polyurethane?

Can Araldite be sanded easily? I've always used Plastibond, but the idea of Araldite setting clear we like. If we did not tint it at all how would it look? We do not want a shiny surface.

We have small craters in the top with polyurethene in them. Do we put the Araldite in these to cover the poly? Once finished, how will these craters look?

I've bought a Metabo SXE-450 random sander for the job. Thinking to level the whole slab out with this and a steel ruler for reference.

Thanks as always for all your help, we really need it now. :B

Dave & Di.

[Skew ChiDAMN!!]

:think:

The Metabo SXE-450 is a nice unit. Take it from a bloke who bought one only a few months ago and still has tool-lust for it. :wink:

A wide-enough drum-sander would be perfect but, sadly, I can't point you to anyone in SA with one. The ROS & a steel ruler will do the job provided you have the time to do it. Either way should solve any & all questions about the little "dimples" of poly.

That'll still leave the poly in the deeper knots of course, but I'd take up RufflyRustic's suggestion of experimenting on an off-cut - or anything with a knot or two to fill will do, to see how epoxy/araldite/whatever goes over the poly. Use 'em to test a few different fillers, they'd also answer later questions about "will it sand?" and choice of finish over whatever's chosen.

(An offcut would be better, as that'd give you a more accurate idea of colour changes too. But if you haven't one too hand...)

Personally I avoid Araldite, as I find that for any decent thickness of fill it always traps air-bubbles. And if I'm still trying to extract those bubbles when it starts to gel, well... I end up with a right cloudy mess.

Also, I'm not sure what to use as a wetting agent with Araldite. (Although I've been told small amounts of turps will thin it & extend the working time) With epoxy, I can simply dampen the knot with some of the drying agent before doing the pour, to reduce the chance of bubbles being trapped in the grain.

Even if you don't want the filer to be Xtal clear, you don't really want airbubbles trapped in it. :no: Tinting it can be effective, especially if it's only a smokey effect. Something else done more easily with epoxy than araldite.

Epoxy can be sanded/burnished to a matt finish provided you give it enough time to cure. Like, weeks. Rustin's Burnishing Cream (sold to burnish back Rustin's Plastic Finish) works well for me.

As for where the poly has soaked into the end-grain around the knots, the news isn't good: get used to it. They're a part of the knot now. Nothing I can think of will remove all the Poly, not without leaving something behind. It you're lucky, the mark just becomes less obvious.

Under the finish no-one will give a second thought towards 'em... except you & your SWMBO. (Been there, done that. :sigh:)

[Petethebutcher]

Hi Dave,
You have brought out some interesting solutions for your job. I'm sorry I can't add anything as I'm still in the planning stage of a similar project. However I once read an article where the epoxy that filled the cracks etc was coloured black to add to the rustic look.
Cheers
Peter

[Tonyz]

not trying to be rude but what happened to/with Bodgy from ?

[Harry72]

Mate when you coat the whole slab in polyU you will not see those edges of the filled area as the whole slab will be the same colours!

You can use polyU as filler(its not ideal but it works), but it must be layered on thinly otherwise as it dries it will crack. If you keep tipping polyU into the cracks and letting it drain out and set it will eventually fill after many applications.

Epoxy/casting resin would have been the best but it will drain through just like the ployU.
Oh and araldite is epoxy resin, hint dont use the 5min stuff for this application!

[Skew ChiDAMN!!]

You can use polyU as filler(its not ideal but it works), but it must be layered on thinly otherwise as it dries it will crack. If you keep tipping polyU into the cracks and letting it drain out and set it will eventually fill after many applications.

I'd taken him to mean he wanted the knots and borer holes in the side filled flush with the surface. They look to be fairly large 'oles and would take a trillion coats to fill. Otherwise, as you said, they'd crack.


Epoxy/casting resin would have been the best but it will drain through just like the ployU.

Yup. But you can plug the bottoms of cracks/gaps with duct tape/plasticine/whatever and totally fill the holes/cracks completely in one poor if you use a fluid enough epoxy.


Oh and araldite is epoxy resin, hint dont use the 5min stuff for this application!

It's fairer to say that Araldite is "an" epoxy resin. They're not all created equal, after all. (I won't have the 5 or 15min stuff in my shed. :no:)

In my experience Araldite tends to be too thick to flow through deep cracks, and on warm days can still start to gel very quickly, even with reduced amounts of dryer. Great for gluing things together, but not so good as a filler. Gimme good, runny stuff every time. :;

[Harry72]

"Yup. But you can plug the bottoms of cracks/gaps with duct tape/plasticine/whatever and totally fill the holes/cracks completely in one poor if you use a fluid enough epoxy."

I realise that Skewy, but any thicker than 5~6mm and you can risk cracking and face some shrinkage.
Your spot on with the Araldite, its not designed to be a good filler its designed as a glue.

[davep]

Hi gang,

Thanks for all the info. I guess we'll have to leave the poly borders and hope once it's finished that thay'll not be so noticable.

We are worried about using epoxy as it always seems to finish shiny, not to mention sounds difficult to sand back down. Is there a putty product that would work in all our cracks and holes? Near black or dark brown is the colour we'd want.

Do we use builder's bog as suggested? Is this like Plastibond? I ask as I certainly have used Plastibond over the years, although never coloured it.

Feast Watson Flat Proof is probably the final coat we'll apply, have used this on another bit of furniture being a bench chair. Not sure if it is heavy duty enough for a bar top though,

Thanks again, Dave & Di.

[davep]

Thinking "Plastibond Builder" with black oxide might be our answer. As suggested though I need to try an offcut, sadly will only have a tiny bit.

Each end of the slab needs to be cut square, do I just mark it up and cut away? I have a 8 1/4" 1450 watt circular saw The slab is 2" thick. Will this be okay?

Thanks, Dave.