# Cracked Tabletops



## jonross667 (Jan 26, 2018)

Hello, Jon here, i'm new to woodworking. I haven't had any training other than trial and error, and I've now had two of my poplar table tops crack. They were built around the same time and I used the same methods for both. I found some plans online to work off. Both tables have cracked lengthwise with the grain. Both tables were edge glued. I attached a "border" around the tables (used kregg jig for attaching) and then glued particle board to the underside to help with warping. As pictured, both tables have the trestle style bottom. and the table top is attached to the leg in 6 locations with screws. As i've been looking through other forums, I'm well aware that its my own mistake that the table cracked. What i'm looking for is advice on how to attach a border around the table that still allows movement. and also best methods to attach the tabletop to the legs. Both tables are in the homes of the people who bought them. I got the dreaded phone call. Thanks for any help.


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## rwe2156 (May 7, 2014)

A top has to be able to move so any time it is attached in a way that prevents, that, things happen.

In this case, the crack was caused by wood shrinkage but the would couldn't move. Looks like its along the glue line. Also, the moulding attached to the end can be a problem. Better to route a profile in the end grain.

Reglue it & don't use pocket screws. Use attachment blocks with oblong screw holes that allow for movement.


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## Loren (May 30, 2008)

Anna White in particular has been noted for
publishing designs with troubling approaches
to wood movement.

There's no issue with pocket screwing the border
on the long sides. The end grain you would need
to use some variant of a "breadboard end". It
can be done by routing elongated slots on the
outside face of the border, installing screws and
filling the holes with elongated wood plugs. 
Another way to do it it to route a long dovetail
in the back of the border piece. Sections of 
mating dovetail are screwed to the exposed 
end grain. The border piece would need to have
the dovetail profile filled at one end.

Still another approach which I am not recommending
for aesthetic reasons is to make new end caps
from end grain poplar. Since this wood will move
the same as the inside sections you can probably
get away with gluing or screwing it on from the 
back. Taking it further, the table top can be mitered
at 45 degrees and an end cap with the same grain
orientation cut to fit the miter and form a "waterfall" 
edge. This is however a technically tricky thing to 
get right, depending on the tools you have on
hand. Some people claim to do it with a Festool
guide rail saw, but I have never tried.


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## a1Jim (Aug 9, 2008)

I agree with Loren about Annie white's designs, she may have attractive designs but she knows nothing about wood movement and very little about joinery.Gluing the top to the apron is a guaranteed approach to a cracked tabletop, although wood can be allowed to move with pocket screws by enlarging the hole pocket screws go in, I don't believe that's not always the most fail-safe approach, the more traditional approaches have distinct advantages over pocket screws.(see link) another issue is the end boards goes across the grain of the table top also is trying to restrict the top from moving. (see 2nd link)
http://www.craftsmanspace.com/knowledge/17-ways-to-fasten-a-tabletop.html
http://www.finewoodworking.com/2003/10/01/understanding-wood-movement


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## a1Jim (Aug 9, 2008)

BTW Welcome to Ljs


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## Carloz (Oct 12, 2016)

Your particle board base is the problem. Wood shrinks quite significantly when humidity drops. particle board does not.
Other reason of cracking mentioned in previous posts are of no importance here since the table top did not shrink because the wood was glued to the particle board.
You could go the route you chose but making your boards 1/16" or so thick. You'd save a lot of wood and prevent any problems with wood movement. Manufacturers go this way in maybe 95% of furniture these days.
I see no way of fixing it now besides taking off the top, making a chicken coop of it and making another top properly either by gluing veneer to it or changing the design to allow for wood movement.


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## a1Jim (Aug 9, 2008)

I agree with Carloz ,I missed the fact that you glued your tabletop to particle board.I don't quite agree that the other inhibitors to wood movement are "of no importance" but the gluing of the top to the particle board is probably of the highest importance to start with, the removal of that, then the other issues still need to be taken care of too.


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## Lazyman (Aug 8, 2014)

Are you saying that you glued particle board to the underside of the top? if so, that sounds like the biggest mistake to me and what caused the joints between the tops individual boards to fail the way they did. Basically, my theory is that you locked each board in place and when the humidity dropped from what it was when it was built , the boards contracted laterally and pulled the joints apart because the PB backer would not let them move. Assuming that you cannot remove the glued on particle board, the only thing that I can think of that *might *allow you close the gaps would be to take a router or circular saw and cut grooves in the particle board lined up with each of the joints in the top. Not sure that you can actually repair the failed joints, because you usually cannot reglue PVA joints without removing the old glue, but it might help prevent them from getting any worse. If the end pieces are also glued on those will also restrict the lateral movement of the top and removing and reattaching with oversized pocket holes and no glue may help and make it easier to cut the grooves in the PB all the way to the end.

Of course, if I misunderstand…nevermind! ;-)

For future reference, battens using screws in oversized holes or slots would be a better way to help prevent or at least reduce warping while still allowing for wood movement.


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## wormil (Nov 19, 2011)

Step one is give the people their money back. There are many outstanding books on furniture making, read some and don't sell anything until you have practiced and know what you are doing.


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## jonross667 (Jan 26, 2018)

Thanks for all the advice. I'll be going to look at the table Tuesday to see what can be done. I'll post more pictures at that point. 
I had a local lumber company do the glue-up for the table top, and they suggested that I attach some sort of furniture grade backer board, one that was a dry material. That's why I went with the PB. But, I now realize that was my first big mistake.


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## jonross667 (Jan 26, 2018)

Thank you, are you saying to attach a backer board with oblong screw holes? Or would that be for the border piece on the ends?



> A top has to be able to move so any time it is attached in a way that prevents, that, things happen.
> 
> In this case, the crack was caused by wood shrinkage but the would couldn t move. Looks like its along the glue line. Also, the moulding attached to the end can be a problem. Better to route a profile in the end grain.
> 
> ...


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## jonross667 (Jan 26, 2018)

Thank you. I'll check out those articles you posted.



> I agree with Loren about Annie white s designs, she may have attractive designs but she knows nothing about wood movement and very little about joinery.Gluing the top to the apron is a guaranteed approach to a cracked tabletop, although wood can be allowed to move with pocket screws by enlarging the hole pocket screws go in, I don t believe that s not always the most fail-safe approach, the more traditional approaches have distinct advantages over pocket screws.(see link) another issue is the end boards goes across the grain of the table top also is trying to restrict the top from moving. (see 2nd link)
> http://www.craftsmanspace.com/knowledge/17-ways-to-fasten-a-tabletop.html
> http://www.finewoodworking.com/2003/10/01/understanding-wood-movement
> 
> - a1Jim


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## jonross667 (Jan 26, 2018)

Yes, i glued particle board under the table top. As was recommended by the company who I had make the table top for me. I will try the cutting of joints in the particle board to see if that will help relieve the stress on the wood. Also, yes - the end border piece is glued on. Thanks! 


> Are you saying that you glued particle board to the underside of the top? if so, that sounds like the biggest mistake to me and what caused the joints between the tops individual boards to fail the way they did. Basically, my theory is that you locked each board in place and when the humidity dropped from what it was when it was built , the boards contracted laterally and pulled the joints apart because the PB backer would not let them move. Assuming that you cannot remove the glued on particle board, the only thing that I can think of that *might *allow you close the gaps would be to take a router or circular saw and cut grooves in the particle board lined up with each of the joints in the top. Not sure that you can actually repair the failed joints, because you usually cannot reglue PVA joints without removing the old glue, but it might help prevent them from getting any worse. If the end pieces are also glued on those will also restrict the lateral movement of the top and removing and reattaching with oversized pocket holes and no glue may help and make it easier to cut the grooves in the PB all the way to the end.
> 
> Of course, if I misunderstand…nevermind! ;-)
> 
> ...


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## a1Jim (Aug 9, 2008)

Hi again
I teach adult woodworking and this term I'm actually teaching a class on table making.
I think you misunderstood you don't need a baker board at all, you were given some bad advise where you got your wood, no one puts backer boards on hardwood tables.It's the apron end boards(breadboard ends)that needs the connections that allow for wood movement.please do some research on wood movement and moisture content and breadboard ends before you make any more furniture for customers. 
By the way, your tables look nice but it's all about the details.


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## a1Jim (Aug 9, 2008)

When people talk about tables here are some the names of the different parts of a table.


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## jonross667 (Jan 26, 2018)

For my table, I didn't have the traditional apron as mentioned above. I think understand how to join to the traditional apron with different types of fasteners. I have some of the metal Z type. What is the best method to attach a table top to pedestal legs? Would you use similar fasteners? 


> Hi again
> I teach adult woodworking and this term I m actually teaching a class on table making.
> I think you misunderstood you don t need a baker board at all, you were given some bad advise where you got your wood, no one puts backer boards on hardwood tables.It s the apron end boards(breadboard ends)that needs the connections that allow for wood movement.please do some research on wood movement and moisture content and breadboard ends before you make any more furniture for customers.
> By the way, your tables look nice but it s all about the details.
> ...


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## a1Jim (Aug 9, 2008)

Looking again at your table I realize it's a trestle table. with that style table, you screw the top board of you end legs but you elongate the holes so that the wood can move across the grain (width of the top) no glue.


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## wormil (Nov 19, 2011)

> Yes, i glued particle board under the table top. As was recommended by the company who I had make the table top for me. I will try the cutting of joints in the particle board to see if that will help relieve the stress on the wood. Also, yes - the end border piece is glued on. Thanks!
> - jonross667


You really should refund their money and walk away, better yet, haul the table away for them. What you're doing is not okay. You are taking advantage of people and selling poorly designed and terribly built furniture because you can't be bothered to learn the right way to build things. And now you will attempt some half-ass repair that will only delay the inevitable failure.

edit; to be clear-if it were for your own house, more power to you but it's the selling that is wrong.


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## jonross667 (Jan 26, 2018)

Hey, thanks buddy. Very helpful. The reason i'm on this site is to learn about the mistakes I've made. Well aware of that. As I said before, looking for advice for woodworking. You can keep your "how to be a jackass" advice to yourself.

You really should refund their money and walk away, better yet, haul the table away for them. What you re doing is not okay. You are taking advantage of people and selling poorly designed and terribly built furniture because you can t be bothered to learn the right way to build things. And now you will attempt some half-ass repair that will only delay the inevitable failure.

- Rick_M
[/QUOTE]


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## jonross667 (Jan 26, 2018)

First table was for a cousin. 2nd was a reference from a friend. So my "half-ass repair" will be to make a new top or refund them. 


> Yes, i glued particle board under the table top. As was recommended by the company who I had make the table top for me. I will try the cutting of joints in the particle board to see if that will help relieve the stress on the wood. Also, yes - the end border piece is glued on. Thanks!
> - jonross667
> 
> You really should refund their money and walk away, better yet, haul the table away for them. What you re doing is not okay. You are taking advantage of people and selling poorly designed and terribly built furniture because you can t be bothered to learn the right way to build things. And now you will attempt some half-ass repair that will only delay the inevitable failure.
> ...


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## jerryminer (Jun 15, 2014)

OK, you figured out that these tops were not built right.

IMHO, you have 3 main issues:

1. the PB glued to the top
2. the cross-grain edging
3. the attachment of top to base.

The real "fix" is a new top. The PB and the cross-grain edging will be problematic forever. In order to incorporate an "edging" as you have done, you have these options:

1. make the edging into a "thickened edge"-with the grain running in the same direction as the rest of the top.
2. make a breadboard end-built to allow wood movement
3. Make the top out of a veneered "stable" panel (like plywood or mdf)

Attaching the top to the base (assuming a solid-wood top): screws are fine, as long as the holes are slotted to allow wood movement.

Not allowing for wood movement is the #1 rookie error. Welcome to the club! I'm sure this will serve as a good learning experience, and that your next table will be much improved.


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## jonross667 (Jan 26, 2018)

Thank you, this was very helpful. I will keep all these suggestions in mind, do some more research and learn the correct way to do this. 
I've thought about using a plywood top. But was worried about the durability of the veneer as opposed to a solid hardwood top. 
Yes, its been quite the learning experience so far.



> OK, you figured out that these tops were not built right.
> 
> IMHO, you have 3 main issues:
> 
> ...


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## Loren (May 30, 2008)

I would say the tops can be salvaged but it
will be some work. The particleboard can
be removed with an adze, perhaps with a
linoleum scraper. The edging would be removed
and then then ripped down the crack and 
re-joined. After that a trip through a wide
belt sander may be beneficial.

Cross-grain "battens" can be added to the
bottom of table tops to help keep them flat.
The battens should be attached with screws 
in slotted holes. Tables with aprons don't 
need them.


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## jonross667 (Jan 26, 2018)

I will try and salvage the top, its a big one. 4/4 and almost 10ft long. It would be nice to save it. With the slotted holes, would you put a washer on with the screw? and just hand tighten the screw?
Thanks for the info!



> I would say the tops can be salvaged but it
> will be some work. The particleboard can
> be removed with an adze, perhaps with a
> linoleum scraper. The edging would be removed
> ...


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## jerryminer (Jun 15, 2014)

> ... the durability of the veneer as opposed to a solid hardwood top.


Durability: Yes, if someone *gouges* the table, the core will show through, but if "ordinary wear" is the concern, remember that the finish will wear first, before the veneer-and a hardwood edging will take the nicks and dents at the edges. A responsible owner will re-finish when the finish is worn out-before the veneer is worn through.

I personally prefer solid wood tables to veneer, but I also don't include cross-grain edging in my tables.


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## a1Jim (Aug 9, 2008)

Jon
Just typing close to what Loren said. Knowing how particle board is to deal with it and removing it has to do with how much glue and how often you glued it if you just put some lines of glue then you may just have just a few lines to scrape off with perhaps a paint scraper,it might work but if you spread glue all over the top then you jobs going to be a big one, and depending on what your budget will allow it will be far easier to just remake the top..if you have experiance with a belt sander and have one once you just hamostly glue to take of then you could use that too,but,belt sanders are known as project destorers so if you haven't used one much your taking a gamble using one


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## Loren (May 30, 2008)

> I will try and salvage the top, its a big one. 4/4 and almost 10ft long. It would be nice to save it. With the slotted holes, would you put a washer on with the screw? and just hand tighten the screw?
> Thanks for the info!
> 
> I would say the tops can be salvaged but it
> ...


You don't have to use these, but they are an
option. Fender washers work too, but the 
elongated washers are a nice touch if you
don't mind taking the time to make the slots.


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## wormil (Nov 19, 2011)

> You can keep your "how to be a jackass" advice to yourself.
> 
> - jonross667


You've got that down pat, I'm trying to teach you integrity.



> So my "half-ass repair" will be to make a new top or refund them.
> - jonross667





> I will try and salvage the top, its a big one.
> - jonross667


Hmm.


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## a1Jim (Aug 9, 2008)




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## wormil (Nov 19, 2011)

Edit, nm, I'll leave it be.


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## RichT (Oct 14, 2016)

>


But, I'm not nice, so that exempts me.



> - a1Jim


Oh, yes you will. Remember, nice guys finish last.


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## a1Jim (Aug 9, 2008)

Ok, I got it I'm a loser. I Use to be more cynical too Rick But I found out I didn't know everything and that no one appointed me judge over anyone else, then I turned 19.


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## RichT (Oct 14, 2016)

> Ok, I got it I m a loser. I Use to be more cynical too Rick But I found out I didn t know everything and that no one appointed me judge over anyone else, then I turned 19.
> 
> - a1Jim


I'm Rich, the other stuff was from Rick. He's mean, I'm just sarcastic.


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## a1Jim (Aug 9, 2008)

Are you sure ) hey I'm being judgemental by suggesting you were being Judgmental.we are what we are no matter who has issues with that no one's going to change the way we think? You have good night Rick and you too Rich:


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## RichT (Oct 14, 2016)

> Are you sure ) hey I m being judgemental by suggesting you were being Judgmental.we are what we are no matter who has issues with that no one s going to change the way we think? You have good night Rick and you too Rich:
> 
> - a1Jim


I feel like I'm watching The Waltons. Night Rick, night Jim.


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## jonross667 (Jan 26, 2018)

If the top can be salvaged by means of what others have said, i'll give it a try. If not, well its my problem. I've owned up to my mistake. Move along Rick.


> You can keep your "how to be a jackass" advice to yourself.
> 
> - jonross667
> 
> ...


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## RichT (Oct 14, 2016)

OK, humor aside, back to the OP. I don't think the shop that glued up the top gave you bad advice, I just think you misinterpreted it. For a top that size - and I'm guessing it was glued up from 4/4 poplar - a couple of crosspieces (battens) to stiffen it would be a good idea. If I were doing it, I'd use 3 or 4 inch wide 6/4 or 8/4 hardwood, maybe 80% the width of the table, and miter the ends so no one knocks their knee on a blunt end. Those would be the members I attached the leg column to as well, with some angle blocks for strength and stiffness.

All of the comments above about movement come into play here. You would not use any glue, and you would attach the battens to the bottom of the table in some fashion that allows the table to expand and contract without being constricted. Z-clips, oblong screw holes, whatever. You said you understand that part, so you're good. The glue was what did you in.


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## jerryminer (Jun 15, 2014)

> I don t think the shop that glued up the top gave you bad advice, I just think you misinterpreted it. - Rich





> ... i glued particle board under the table top. As was recommended by the company who I had make the table top for me. - jonross667


If the advice indeed was to glue PB under a solid wood top, then it was, indeed, bad advice. Battens would have been good advice, glued PB, no.


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## jonross667 (Jan 26, 2018)

thanks, that's helpful advice as well. Hardwood battens. 


> For a top that size - and I m guessing it was glued up from 4/4 poplar - a couple of crosspieces (battens) to stiffen it would be a good idea. If I were doing it, I d use 3 or 4 inch wide 6/4 or 8/4 hardwood, maybe 80% the width of the table, and miter the ends so no one knocks their knee on a blunt end. Those would be the members I attached the leg column to as well, with some angle blocks for strength and stiffness.
> 
> - Rich


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## Manitario (Jul 4, 2010)

I don't have any advice that hasn't already been given, other than welcome to woodworking! We all mess up, no matter how much experience. I have $70 of 8/4 cherry that I just turned into very pretty firewood last week.

Best to learn the big lessons, eg. wood movement, finishing, properly sizing joinery etc. early on!


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## jonross667 (Jan 26, 2018)

O man, sorry for the loss! Thanks for the encouragement. 


> I don t have any advice that hasn t already been given, other than welcome to woodworking! We all mess up, no matter how much experience. I have $70 of 8/4 cherry that I just turned into very pretty firewood last week.
> 
> Best to learn the big lessons, eg. wood movement, finishing, properly sizing joinery etc. early on!
> 
> - Manitario


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## RichT (Oct 14, 2016)

> I don t think the shop that glued up the top gave you bad advice, I just think you misinterpreted it. - Rich
> 
> ... i glued particle board under the table top. As was recommended by the company who I had make the table top for me. - jonross667
> 
> ...


Congratulations on selectively editing the thread to negate the value of my comment. Through careful editing you left out the OP's original text, which I referred to in my post:

"I had a local lumber company do the glue-up for the table top, and they suggested that I attach some sort of furniture grade backer board, one that was a dry material. That's why I went with the PB. But, I now realize that was my first big mistake."

To which I replied:

"a couple of crosspieces (battens) to stiffen it would be a good idea. If I were doing it, I'd use 3 or 4 inch wide 6/4 or 8/4 hardwood"

You have a great future at CNN, my friend.


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## jerryminer (Jun 15, 2014)

Rich-I did not mean to offend or insult, or to misinterpret your comments. My apologies.

I read that the shop had advised gluing PB to the top. I consider that bad advice. I stand by my statement:



> If the advice indeed was to glue PB under a solid wood top, then it was, indeed, bad advice.


Your advice to:


> use 3 or 4 inch wide 6/4 or 8/4 hardwood, maybe 80% the width of the table


was good advice. Maybe we have a different understanding of what "*furniture grade backer board*" means. Doesn't sound like battens to me.


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## RichT (Oct 14, 2016)

> Rich-I did not mean to offend or insult, or to misinterpret your comments. My apologies.
> 
> - jerryminer


It's OK, Jerry. In defense of both of our posts, the OP first wrote:

"I had a local lumber company do the glue-up for the table top, and they suggested that I attach some sort of furniture grade backer board, one that was a dry material. That's why I went with the PB. But, I now realize that was my first big mistake."

... but subsequently posted:

"Yes, i glued particle board under the table top. As was recommended by the company who I had make the table top for me."

So, any misunderstanding is totally understandable. I can't believe I just said that with a straight face, but you know what I mean…


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## jerryminer (Jun 15, 2014)

> any misunderstanding is totally understandable.


LOL. Couldn't have said it better myself.


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## 000 (Dec 9, 2015)

Been there :>/


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## RichT (Oct 14, 2016)

> Been there :>/
> 
> - jbay


Should I try to do some more… 25 or 624?


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## PCDub (Sep 24, 2017)

what the hay? easy boys, eeeeeaaaaasssssyyyyyy…..


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