I need some more help, advice

[Sonny]

The checked trestle leg unit is now flexing at/along the check line. I'm p repping it, to apply the epoxy in the crack. I can apply clamps and close the lower part of the crack by about 1/4", from about 1/2" to 5/16". The t op edge of the unit hardly budges, when clamped.

There are splinters inside the crack, from one side to the other, which I h ope will help grab on and hold the epoxy, aiding the epoxy to hold the halv es together firmly.

Questions:

1) Do you think the epoxy, alone, will hold the two sides, as is, firm enou gh, so that there is no flexing at the check line? OR..

2) Would you recommend putting dowels, diagonally, on/through the top and b ottom (3-1/2") edges.... not on the faces, to help secure the check line fr om flexing? I'm considering applying dowels. I don't want to use metal b olts.

3) Once epoxied (and doweled?), should I clamp the crack more closed, or sh ould I leave it as naturally open/wide, as it is unclamped? If I clamp it , I'm wondering if there will be a significant spring-back, once the clamps are removed, hence compromising the epoxy bond. It's hard to tell how mu ch force the spring-back pressure is, when dry clamping & releasing. It ta kes some good strong cranking, on the clamp handles, to close the crack by 1/4". The first 1/8" closes fairly easy.

4) Is there any other options to consider, for further securing/preventing the flexing at the crack line?

Thanks for any help. Sonny

[Lew Hodgett]

The checked trestle leg unit is now flexing at/along the check line. I'm prepping it, to apply the epoxy in the crack. I can apply clamps and close the lower part of the crack by about 1/4", from about 1/2" to 5/16". The top edge of the unit hardly budges, when clamped.

There are splinters inside the crack, from one side to the other, which I hope will help grab on and hold the epoxy, aiding the epoxy to hold the halves together firmly.

Questions:

1) Do you think the epoxy, alone, will hold the two sides, as is, firm enough, so that there is no flexing at the check line? OR..

2) Would you recommend putting dowels, diagonally, on/through the top and bottom (3-1/2") edges.... not on the faces, to help secure the check line from flexing? I'm considering applying dowels. I don't want to use metal bolts.

3) Once epoxied (and doweled?), should I clamp the crack more closed, or should I leave it as naturally open/wide, as it is unclamped? If I clamp it, I'm wondering if there will be a significant spring-back, once the clamps are removed, hence compromising the epoxy bond. It's hard to tell how much force the spring-back pressure is, when dry clamping & releasing. It takes some good strong cranking, on the clamp handles, to close the crack by 1/4". The first 1/8" closes fairly easy.

4) Is there any other options to consider, for further securing/preventing the flexing at the crack line?

------------------------------------------------------------------ Do yourself a big favor and run the following:

Cover a piece of plywood with some plastic sheet.

Take a couple of furring strips say 2-1/2" x 12" x 3/4" and screw them to the plastic covered plywood about

3/4" to 1" apart to create a gap about 12" long.

Mix up about 2-4 ounces of epoxy, then mix in enough microballoons to thicken to the consistancy of mayonaisse.

Use a paint stick to fill the gap with the thickened epoxy.

Wait 2-3 days, then unscrew from plywood and play with it.

Gain some confidence in the epoxy fairing putty joint, then get back to me.

At this point in time your lack of experience with epoxy fairing putty is creating a lot of concern that is unnecessary.

Lew

[dadiOH]

It really doesn't need much help.

I think the epoxy alone would be sufficient.

Can't hurt. Why don't you want to use metal?

I probably would not try to close it. If I did, I'd not use great pressure, would settle for the1/8th. If you do clamp it (at all) plan on leaving the clamps on for at least a week...epoxy cures overnight but not completely for at least a week.

Bowtie inserts. Or even diagonally crossing dadoes with wood inserts. I'd do neither, would wait to see the effects of epoxy alone first.

Be sure to scrape out any rot or soft wood from the checks. You'll need to either thicken the epoxy or put tape across the bottom so the epoxy doesn't run out. Good luck, it is an interesting project.

[Richard]

Sonny, for what it's worth, microballoons are NON-structural fillers.

If the idea is to clamp the cracks together AT ALL, micro won't hold for long. Use milled fiber (cotton) fillers or the like for that.

But if there will be no tension on the repair, micro works fine.

[Sonny]

Both your comments has educated me. I do have limited experience with epox y, and no eperience for this kind of application, and need the learning. M y previous epoxy experience was for filler applications, for bad powderpost beetle holey brittle wood repairs, so that upholstery stapling would be se cure.... and I repaired broken composite stool legs, both with System3's ep oxy.

For this project's application, I purchased West Systems' G-Flex 650-8 epox y.

To my understanding, this is the more liquid product, as I intended it to f low deep into the crack, for max contact and volume. Maybe I should have p urchased the thicker G-Flex 855-8, but not sure how much I will be able to press deep into the crack, especially in the more narrow spaces. I don't k now just how thick the 855-8 is. With the slab 3-1/2" thick, I thought to work the epoxy in from both sides of the slab.

Okay, so I'm off to get more epoxy and some microballoons. I do have some thick (2" & 6") cypress wood pieces, with cracks, that I may fill/test, to and see how those mock repairs work out, along with Lew's test/experience s uggestion.

Thanks. Sonny

[dadiOH]

Epoxy flows very well. Slowly but well, you won't have to press (with unthickened epoxy).

Good idea, it will educate you :)

[Nick]

There are splinters inside the crack, from one side to the other, which I hope will help grab on and hold the epoxy, aiding the epoxy to hold the halves together firmly.

Questions:

1) Do you think the epoxy, alone, will hold the two sides, as is, firm enough, so that there is no flexing at the check line? OR..

2) Would you recommend putting dowels, diagonally, on/through the top and bottom (3-1/2") edges.... not on the faces, to help secure the check line from flexing? I'm considering applying dowels. I don't want to use metal bolts.

3) Once epoxied (and doweled?), should I clamp the crack more closed, or should I leave it as naturally open/wide, as it is unclamped? If I clamp it, I'm wondering if there will be a significant spring-back, once the clamps are removed, hence compromising the epoxy bond. It's hard to tell how much force the spring-back pressure is, when dry clamping & releasing. It takes some good strong cranking, on the clamp handles, to close the crack by 1/4". The first 1/8" closes fairly easy.

4) Is there any other options to consider, for further securing/preventing the flexing at the crack line?

Thanks for any help. Sonny

Just a thought for which I might be laughed out of court. The check is a natural feature of this fine looking piece of timber. Clamp and glue are going to move the stresses elsewhere. Why not retain it as a significant part of the structure? If it were me I would look at making some butterfly or infinity symbol (figure of 8 on its side) inserts and laying these into the (lightly) clamped timber. Inserts of similar or contrasting timber. Of course this may be against the design ethic but nothing is set in stone. The voids could afterward be filled if required. I wouldn't.

Just my 2p's worth. Nick. UK.

[Michael]

prepping it, to apply the epoxy in the crack. I can apply clamps and clos e the lower part of the crack by about 1/4", from about 1/2" to 5/16". The top edge of the unit hardly budges, when clamped.

Hi Sonny,

I'm sorry, I haven't been following all the threads on your project, but I have a question. Have you put a moisture meter on this piece?

[Nick]

Hi Sonny,

I'm sorry, I haven't been following all the threads on your project, but I have a question. Have you put a moisture meter on this piece? Showing my ignorance perhaps, but how will knowledge of the moisture content be of any assistance at this stage of the proceedings? Nick. UK.

[Lew Hodgett]

For this project's application, I purchased West Systems' G-Flex 650-8 epoxy.

To my understanding, this is the more liquid product, as I intended it to flow deep into the crack, for max contact and volume. Maybe I should have purchased the thicker G-Flex 855-8, but not sure how much I will be able to press deep into the crack, especially in the more narrow spaces. I don't know just how thick the 855-8 is. With the slab 3-1/2" thick, I thought to work the epoxy in from both sides of the slab.

Okay, so I'm off to get more epoxy and some microballoons. I do have some thick (2" & 6") cypress wood pieces, with cracks, that I may fill/test, to and see how those mock repairs work out, along with Lew's test/experience suggestion.

---------------------------------------------------- The last thing you want to do is try to fill they cracks by dripping epoxy into them. You won't be able to get rid of the damaged wood in the crack before you apply the epoxy.

Thing of yourself as a wood dentist who has to fill a wood tooth and stop the wood decay.

Time to get out your saber saw and hand drill with a forstner bit or a hole saw and open up those cracks so you can get rid of the damaged/rotted wood contained along the side walls of the cracks.

Like the dentist, once you have removed all the decay, it's time to fill the crack(tooth) with fairing putty (epoxy filled with microballoons).

I'd probably open those cracks to 3/4" minimum width.

I'd also drill a 3/4" thru hole with the center at the end of the crack.

That way, you have stopped the crack from penetrating any further into the wood.

You don't need clamps, dowels, nails, etc to get a finished repair.

The only thing you required other than the epoxy fairing putty is patience and good preparation.

Lew

[Sonny]

Why not retain it as a significant part of the structure?

I will maintain the faces as is. I'll just fill the crack with epoxy to co ver up the space and help secure the two haves as best as the epoxy will ad here/hold.

It's green wood, but the surfaces are dry to touch, that's why I earlier as ked for opinions about epoxy for wet/green wood or surfaces. It'll take a few years for the leg units to air dry. I was told, by the kiln guy, not to attempt to kiln dry a slab as this... it would crack and split apart, al l over, and may not function as I want. He said I'd want it to very slowly air dry. I have lots of experience air drying milled lumber, but not figu red, knarled, dense rootball stock as this.

I've done all the trimming I'll do, from it initial large size, so I won't be cutting into any more really wet (interior) wood. I'm hoping the more d ry surfaces will better accommodate the adherence of the epoxy, also.... th e instructions for the G-Flex 655-8 state this is a preferred circumstance. I'm reading the 650-8 instructions, now, probably will have the same comm ents, regarding that.

There appears to be only good solid wood in the crack, no rot, decay or wea k areas. It appears to be good solid wood that has simply checked up the m iddle. The splinters, in the crack, are solid, also, extend across the spa n and they are pretty much holding the two halves together on the bottom en d. The top end has much more robust wood holding the halves together.

When I first cut the slab, there was no flexing along the check line. As t he slab has dried, I'm supposing the check widened, the splinters became mo re prominent/visable and the flexing developed. When cut, I wasn't able to see through the crack, but now the crack has widened and I can easily see through some areas on the bottom end. It may be good that I haven't secure d/filled/"fixed" the check, before now. Allowing some drying and shrinkage may be a good thing, before attempting any "fix".

Today, I bought the G-Flex 655-8, so I have both the more liquid 650-8 and the thicker 655-8. I have some samples poured. I'll see & test the result s in a few days.

Sonny

[Lew Hodgett]

I will maintain the faces as is. I'll just fill the crack with epoxy to cover up the space and help secure the two haves as best as the epoxy will adhere/hold.

It's green wood, but the surfaces are dry to touch, that's why I earlier asked for opinions about epoxy for wet/green wood or surfaces. It'll take a few years for the leg units to air dry. I was told, by the kiln guy, not to attempt to kiln dry a slab as this... it would crack and split apart, all over, and may not function as I want. He said I'd want it to very slowly air dry. I have lots of experience air drying milled lumber, but not figured, knarled, dense rootball stock as this.

I've done all the trimming I'll do, from it initial large size, so I won't be cutting into any more really wet (interior) wood. I'm hoping the more dry surfaces will better accommodate the adherence of the epoxy, also.... the instructions for the G-Flex 655-8 state this is a preferred circumstance. I'm reading the 650-8 instructions, now, probably will have the same comments, regarding that.

There appears to be only good solid wood in the crack, no rot, decay or weak areas. It appears to be good solid wood that has simply checked up the middle. The splinters, in the crack, are solid, also, extend across the span and they are pretty much holding the two halves together on the bottom end. The top end has much more robust wood holding the halves together.

When I first cut the slab, there was no flexing along the check line. As the slab has dried, I'm supposing the check widened, the splinters became more prominent/visable and the flexing developed. When cut, I wasn't able to see through the crack, but now the crack has widened and I can easily see through some areas on the bottom end. It may be good that I haven't secured/filled/"fixed" the check, before now. Allowing some drying and shrinkage may be a good thing, before attempting any "fix".

Today, I bought the G-Flex 655-8, so I have both the more liquid 650-8 and the thicker 655-8. I have some samples poured. I'll see & test the results in a few days.

------------------------------------------------------------------ The further this conversation goes, the more convinced that you should wait another year before continuing this conversation.

Especially with your knowledge of air drying lumber.

A year from now, the cracks will still be there, only things will be a little more stable.

Try to push mother nature and she will bite you in the ass.

Just my nickel.

Lew

[nailshooter41]

Ayup. Going with Lew on this one. I helped a friend's friend in his shop and we glued together a bunch of mesquite. Now mesquite is touted as North America's most stable wood, and having worked with a lot of it, I can beli eve it.

But like any wood, until it is dry enough to be stable, it does what it wan ts. I like using epoxy to fill cracks. I color it with copier toner, tone r with brass shavings, and anything else that catches my fancy that won't s poil the epoxy.

More than once though, I have carefully cleaned out a crack or lines of sev ere wind shake to and filled them, only to have the crack move over and sta rt up again. If the wood is unstable, using epoxy as you have described si mply won't be a reliable method to use. And you should remember that the l arge the piece of wood you are tackling, the great the movement will be as the wood fibers release their energy.

With the pent up energy stored in the wood fibers starts to release (which is readily seen in some woods that warp terribly when drying) while it is w et, you never know what you will get or how well your repair will hold.

Robert

[Sonny]

urther this conversation goes, the more convinced that you should wait anot her year before continuing this conversation. Especially with your knowledg e of air drying lumber. A year from now, the cracks will still be there, on ly things will be a little more stable. Try to push mother nature and she w ill bite you in the ass. Just my nickel. > Lew Ayup. Going with Lew on this one.

Agreed. My present fix is to help stablize the flexing and, to some degree , make a repair, albeit a temporary one. I want to get the leg units in as sembly condition, despite the green wood, not in finishing condition. I wo n't be able to finish them, properly, until they dry... in a few years. Th e plan was to get the dining table assembled for use at the camp/farm this hunting season, then fully finish it some years later. I can finish the ta ble top, since it is, essentially, ready for permanent finishing.

One option, I originally thought (posted about, 2 months(?) ago), was to sa w along the check, to remove the visible crack. Initially, I didn't want t he check visable, at all. At that time, I was steered to the epoxy fix opt ion and to color it, for a better appearance. In the future, I'll still ha ve the option of cutting out the check, no matter how much more it expands.

In the future, the table will be easy to disassemble, since these base part s will be keyed mortise/tenon through joints. The keyed mortise/tenon appr oach is the best option for the expected (mandatory?) future disassembling, for making the permanent repairs and for proper finishing. The leg units will continue to air dry, while we use the table. This checked leg unit ne eds to be, at least, temporarily stabilized, for assembly of the trestle bo ard (by end of next week, maybe).

Being able to readily disassemble a large heavy table, as this, is a must. There's no way to conveniently move this large of table, once it's assembl ed. This assemble/disassemble design approach accommodates the present tem porary fix and future permanent fix, of this problematic/checked leg unit.. .. and will accommodate any other problem, I may have with, or refinishing, I may want for, the table's individual parts, later.

Sonny

[Sonny]

In essence, for now and for the present conditions, I'm convinced the epoxy option is my best. All the advice and help is greatly appreciated. Hope to have some feedback and pics by end of next week, or so.

Additionally: We've been using the new shop, at the farm, as a camp. Jona s erected a temp shelf for the TV, on the bathroom wall. We've made a few other improvements, for living conveniences, etc., the past few months. Th at ugly TV shelf needs replacing.

I hope to have the new faux fireplace/mant le/TV shelf completed, maybe, this weekend, so pics may be forthcoming for that, also.

Sonny

[Sonny]

it another year before continuing this conversation. Lew

When I cut the slabs, the checked one was stable, no flexing along the chec k line, so I assumed it may stay that way. The leg unit appeared to be pre tty solid, stable. My post, a few months ago, was about whether to cut ou t the check or fill it, since it was unsightly, only, not that it was struc turally unsound.

The flexing issue didn't develope until recently, during the fitting proces s of the trestle board. Now that the flexing issue has developed, I'm havi ng to rethink my approach for the fitting of the trestle board, without cre ating more "damage". I just need a temp fix, to complete the trestle boar d fitting. The permanent fix and finishing, of both legs, will be done in a few years.

Thanks Lew. Your advise has been really helpful. This epoxy knowledge is definitely an asset. I'm encouraged and anxious to see & test the results o f my samples.

Sonny

[Michael]

. Why not retain it as a significant part of the structure?

cover up the space and help secure the two haves as best as the epoxy will adhere/hold.

asked for opinions about epoxy for wet/green wood or surfaces. It'll take a few years for the leg units to air dry. I was told, by the kiln guy, no t to attempt to kiln dry a slab as this... it would crack and split apart, all over, and may not function as I want. He said I'd want it to very slow ly air dry. I have lots of experience air drying milled lumber, but not fi gured, knarled, dense rootball stock as this.

That was a concern, whether epoxy would set up well on wood that is not dry enough. The other concern is that you will be dealing with this again if t he wood is not sufficiently dry, either with this crack or if others appear elsewhere in the project. Wood checks because it dries unevenly, so if the re was a way to seal off the end grains during the drying process, checks w ould be less likely.

[Bob La Londe]

3/4"

That can be tricky. Most epoxies have the danger of scorching when applied

1/2" thick or thicker.

[Sonny]

t dry enough.

This West System epoxy is specific for wet surfaces. Thanks to Lew and Rob ert for steering me to these epoxies.

I won't do anything special, about this rootball stock. If it splits badly , I'll just deal with what developes, as best I can. My customer (me) is c heap and non-paying, so to heck with perfection, for the moment. I've long worked with all sorts of salvaged and natural stock, with all sorts of def ects. Defects look and function good enough, sometimes. Just another lear ning project, but it'll turn out good... I can feel it.

Last night, I got the trestle board tenons to fit right, in the leg mortise s. Another milestone accomplished.

Yesterday, I brought the table top boards to Laf. Woodworks, to have them p laned on one side. Planing fee $13. Replacement 24" planer blades, becaus e they hit a freaking nail in one board, plus unistall/reinstall labor fee, I ain't saying, but I'm happy with the results. I didn't mind paying the m for those damages. They've done excellent work for me in the past.

Sonny

[Sonny]

Doing several test applications on scrap wood, so the heat issue is no biggie. I checked them regularly and found no significant heat buildup, on any samples. The leg unit's crack is 1/2" and less. I'm confident all will be okay.

Sonny