I'm trying to help out a friend who is also our dog groomer. The quick recap is that she opened her own place after the June startup from Covid, and had this sign made by a local who has a CNC. Nothing about this sign is suiable for the outdoors, though she indicated that would be it's use. Anyway, fast forward to now and the sign has already broke in 2 places and has a serious crack in another 2 places, we're addressing the most serious rack. The sign seems to have been made from a box store pine panel, so the 2 previous breaks were right at the glue seam. Missy's boyfriend "fixed" one using epoxy to re glue the seam. I fixed the second one with biscuits. The edges of the break were covered with whatever glue was used and I couldn't clean it off without (I feared) impacting the sign itself. So I cut it for 4-#0 biscuits and used plastic resin glue to rejoin it, that repair looks solid this morning after I took the clamps off. The reason for biscuits was to get some kind of loose tenon to span the joint, plus I only have 1/2" of wood to work with. The blank was actually about 5/8" thick, but the CNC engraving is just a tad over 1/8" deep and quite profuse across the sign. Now, for the question. I would like to do something to the crack to keep it from getting worse and preventing future failure. I did not think I can safely pull it back together. Anyway I'm considering routing a 1/2" wide groove across the seam, 1/4" deep. Then fill that groove with a douglas fir (that's what i have) piece glued in with plastic resin glue. that glue has good water resistance so should do the job nicely. So, will that work....and other ideas???? After I complete these repairs I told here I wold mount it on a piece of MDO and my plan is to fasten it to the MDO with screws and elongated washers. I'll give that a simple frame and then she can hang it outside. Not part of this, but that paint appears to be fragile, almost like a milk paint I tried using a piece of 3M delicate surface masking tape on it (to mark for the biscuit) and it pulled some off....I had to mark the back side. The pics below are the overall sign (for reference, it's about 29" wide and 13" tall) are the overall sign and closeups of the crack from the front and back side.

Pocket screws come to mind first.  Bow tie inlays may work too.

 

I thought about pocket screws, but given how thin the wood is I'm not sure I could get them to work. However I do have a scrap piece that's the same thickness, I can give that a try this afternoon and see what happens. If that wold work I could put them across all the seams  which might be a permanent fix for the whole sign.I also thought about bowties, and that's still an option although that would be a little more involved than my spline trick. I'd have to make the template. Thanks.

Edited October 23, 20205 yr by Fred W. Hargis Jr

You could put it in a framed glass enclosure with maybe a light or two to light it up at night. Use white oak for the glass to be mounted in.

  I would think if a person starts trying to make the sign itself water proof to be hung outside in the weather he won't end up with the same good looking sign!

trace the outline of the piece onto some plywood, glue together, fill crack with wood putty, touch up paint.

 

makes no sense to spend $100 of time on a $30 sign.

 

learn her lesson, get better stock, re-make the sign (it's CNC, surely they saved the file, just re-run the cutting program on a better piece again)

This type sign may last a year in exposed weather so Jess had a good idea to frame and glass or plex over it. Dan's butterfly patches will be much stronger than a biscuit which is only for alignment and not for strength,

18 minutes ago, Gerald said:

This type sign may last a year in exposed weather so Jess had a good idea to frame and glass or plex over it. Dan's butterfly patches will be much stronger than a biscuit which is only for alignment and not for strength,

I agree and of all things cheesy pine for outside stuff?  Nope.  I doubt the paint is oil base which would have helped with water penatration. Bottom line though is a enclosure would fair much better.  

35 minutes ago, DAB said:

trace the outline of the piece onto some plywood, glue together, fill crack with wood putty, touch up paint.

 

makes no sense to spend $100 of time on a $30 sign.

 

learn her lesson, get better stock, re-make the sign (it's CNC, surely they saved the file, just re-run the cutting program on a better piece again)

I like this idea.   And enclose in a frame to keep out of the rain.

 

 

a biscuit which is only for alignment and not for strength, <- I have to disagree, again.  Otherwise, there are 50+  7' tall cabinets that I've built using only biscuits that must just be piles of wood on the floor.  The strongest, no (depending upon the type of stress).  Strong enough, in many cases (no pun intended).

 

But in this case you are dealing with wood movement that is hard to overcome.

1 minute ago, kmealy said:

I like this idea.   And enclose in a frame to keep out of the rain.

 

 

a biscuit which is only for alignment and not for strength, <- I have to disagree, again.  Otherwise, there are 50+  7' tall cabinets that I've built using only biscuits that must just be piles of wood on the floor.  The strongest, no (depending upon the type of stress).  Strong enough, in many cases (no pun intended).

 

But in this case you are dealing with wood movement that is hard to overcome.

But you did also use glue, Right? After the glue cures it is the glue that holds the joint not the biscuit. Take a biscuit and fold it and you will see they are not very strong.

1 hour ago, Gerald said:

But you did also use glue, Right? After the glue cures it is the glue that holds the joint not the biscuit. Take a biscuit and fold it and you will see they are not very strong.

For edge to edge joints, biscuits are not needed as a good joint is stronger than the surrounding wood in most cases.  I use them for 90 degree joints in plywood; that is what they were developed for.  Those joints have a significant part of end-grain that has weaker gluing strength.

 

The grain in biscuits is at an angle (about 30 or 60 degrees, depending on which axis you measure from).    I'm betting you cannot break a biscuit at 90 degrees to its joint any more than you can break a tenon (Unless you make a tenon or spline in line with the wood's grain.)  Yes, of course you can break a piece of wood along its grain line (what Roy Underhill calls "planes of weakness" vs. "planes of strength")  Even if a biscuit did fail along its grain lines, you now have 2 splines instead of one.

The very first time I used biscuits to make a bookcase, after I took it out of the clamps, it was very rigid.  When I made prior ones with dado and toe-nailed joints on the shelves, there was a lot of flex until I got the back on to stabilize it.

 

I've also built a bunk bed using only multiple biscuits for the headboard rails that also form a ladder to get to the upper bunks.  Those joints were end-grain SYP and would have no strength at all from just glue.

 

I guess we have to agree to disagree on our opinions.  Again.

Sorry for the off-topic tangent.

Edited October 23, 20205 yr by kmealy

1 hour ago, DAB said:

trace the outline of the piece onto some plywood, glue together, fill crack with wood putty, touch up paint.

 

makes no sense to spend $100 of time on a $30 sign.

 

learn her lesson, get better stock, re-make the sign (it's CNC, surely they saved the file, just re-run the cutting program on a better piece again)

As I said, I'll be mounting this onto a piece of MDO, but it's a rectangular piece which will be framed I'm afraid to glue it together though, that's why I'll be using screws and elongated washers....that way the sign can move as needed. As I understand it, this is hardly a $30 sign the CNC work was only a part of the cost; the hand painting was a little laborious. On to the biscuit repair I made, the joint is now quite strong. Since the wood was sized by the glue used in the fabrication of the panel and I had no way to clean it off this worked out very well. Anyway, I did try the pocket screws and they seem to do what I want: reinforce the remaining joints in a way that I hope keeps them from separating. Lastly, I don't do this for hire so I'm not worried about how much time I spend on it. I do agree this is not a long term sign, there isn't anything about it that's "outdoor".

You might have the client check with the original CNC shop, asking for a free ("in-warranty") replacement.  You might help the process by offering to provide a more suitable piece of wood to the CNC process, and then explore a better UV-resistant coating over the paint (the CNC people, assuming they did the painting, should be able to provide a scrap piece with the same paint for you to test coatings on). 

My impression of the CNC "biz" is that it has a great raft of amateurs who got really interested in gears and motors, but have no clue about the media they're carving, or even what comes next (paint, seal, protect).  I think a more balanced industry will eventually treat a CNC service as "just another tool choice", rather than a complete delivery mechanism.  CNC is a step in a production process, not an industry in itself.

1 hour ago, PeteM said:

My impression of the CNC "biz" is that it has a great raft of amateurs who got really interested in gears and motors, but have no clue about the media they're carving, or even what comes next (paint, seal, protect). 

There's no doubt in my mind that's where this guy (or gal) is, they b=can make the thing cut but are clueless about durability, etc. When I give the sign back to my groomer I'll give her my opinion on what happened, but it will be up to her to do whatever she thinks is necessary. At this point I think the repairs I made will give the wood a few years of life, which is probably more than the paint will have.

Why not cut a long, tapered wedge of pine, slip that in with glue, and then do a touchup with matching paint?

Well, I could probably cut the wedge but the painting isn't something that's in my wheelhouse. It's a good idea, I may cut it and ask if she wants me to put it in and she can do the touch up.

To put a pin in this one, I took the sign back to Missy (our groomer) today. The repairs wound up being what some of you suggested. I used pocket screws on the back to reinforce each glue seam, I managed to cut a sliver (wedge) of wood to fill that gap perfectly (as Scott Phillips would say), and mounted the whole thing on an MDO backboard with allowance for wood movement in the sign. She was quite happy with everything, and she had pre-approved that wedge repair on the gap I pictured above. Anyway, the backboard and frame were primed with an oil based primer, and she gets to finish coat it and touch up the wedge repair. As I said above, it's not a long term sign but should last a little while. It will be hanging under a porch cover and out of most of the direct sunlight so that should help a little. Thanks to all for the suggestions!

On 10/23/2020 at 9:04 AM, Fred W. Hargis Jr said:

Nothing about this sign is suiable for the outdoors, though she indicated that would be it's use

That, if true, is  sufficient basis for (1) getting her money back  and if the merchant  refuses ( 2)  a litigation. 

The law on point says that:

If (for example) the customer says to the merchant I plan to use these shoes for mountain climbing and the merchant sells the customer nice   dress shoes and the shoes fail for the purpose  stated then the merchant has to refund the money.

 

So speaking as a lawyer,  if she said the sign is for outdoors    I do not recommend  you do anything at all to the sign  let her try to return it first.

 

On 10/24/2020 at 9:37 AM, PeteM said:

My impression of the CNC "biz" is that it has a great raft of amateurs who got really interested in gears and motors, but have no clue about the media they're carving, or even what comes next (paint, seal, protect).  I think a more balanced industry will eventually treat a CNC service as "just another tool choice", rather than a complete delivery mechanism.  CNC is a step in a production process, not an industry in itself.

You might want to check out some of the projects posted in the CNC forum on this site. Some very good woodworks using a tool to preform a task. Not everyone that has a CNC is an amateur woodworker. 
 

Just a thought. 

On 11/7/2020 at 12:17 PM, Cliff said:

That, if true, is  sufficient basis for (1) getting her money back  and if the merchant  refuses ( 2)  a litigation. 

The law on point says that:

If (for example) the customer says to the merchant I plan to use these shoes for mountain climbing and the merchant sells the customer nice   dress shoes and the shoes fail for the purpose  stated then the merchant has to refund the money.

 

So speaking as a lawyer,  if she said the sign is for outdoors    I do not recommend  you do anything at all to the sign  let her try to return it first.

 

From a legal site:
intended purpose means the use for which a device is intended according to the data supplied by the manufacturer on the label, in the instructions for use or in promotional or sales materials or statements and as specified by the manufacturer in the clinical evaluation

On 11/14/2020 at 1:07 PM, kmealy said:

From a legal site:
intended purpose means the use for which a device is intended according to the data supplied by the manufacturer on the label, in the instructions for use or in promotional or sales materials or statements and as specified by the manufacturer in the clinical evaluation

information from an internet legal site is not the same thing as speaking directly to a licensed attorney.

I am l licensed to practice law in Florida, Penslyvania,   New Jersey and the federal district court of New Jersey, I matriculated with my doctorate in law from Rutgers Newark in 2000