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Has anyone ever attempted installing a back strip after a box was closed? In my haste to shave off a couple of hours on a build I chose not to do a back strip. The set is Philippine Ebony (I think). The sides are very sweet and a great book match.


Not so much with the back. The book match is pretty poor. I don't know if it's the piece of wood or it was cut with a large kerf blade. Whatever the case, I think a back strip would draw your eye away from the lousy book match.


I suppose using a flexible straight edge and some means of clamping it well. I've never tried this before and it would suck to botch it up at this point. Any advice?

Thanks,
Danny

It shouldn't be that tough if you have a steady hand just rout about 1/16" deep. Clamping the strip in would be the tricky part, if it's not too tight I suppose you could just use weights. That wood is called Kamagong in the Philippines. It's pretty, bends well and hard but in my experience it's very prone to checking.

Yes I did , Made same mistake . Couple of thin 3/8" Pieces x 2" wide ( one each side of router base width ) so they will bend to match the back radius but wont flex side to side ... measure CAREFULLY and clamp at head and heel .... Measure again .. check clamps ... insert correct router bit and set depth .... Measure and check clamps again ..... Router it out ....... measure again ...... LOL get the point

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Yeah it's not difficult with a flexible straight edge and light, shallow passes.

But.... IMHO I think that the back as is looks fine. It's wood and wood is imperfect. Further my design eye thinks that adding a back strip will only serve to further draw one's eye to the mismatch.

Leave it as is and call it a feature....

I second hesh/s comment Looks fine to me.

I wouldn't do this. If ANYTHING goes wrong, you will be routing the back off. It looks good as is. Did u do a very tight joint?

The back boards are bastard cut (meaning it goes from vertical grain/quartersawn to flatsawn over the width of the board) and you put the flatsawn area in the middle. While quartersawn/vertical grain is very forgiving regarding bookmatches, you'll never get a perfect bookmatch from flatsawn grain no matter how thin the kerf and/or how good the cut. This is one reason why most guitars you see with bastard cut backs are joined at the quartersawn edge.

As others have said it shouldn't be a big deal to rout if it bothers you... just make sure everything's super secure before hitting the power button

Sounds like a good place to use one of these http://www.leevalley.com/en/Wood/page.aspx?p=64300&cat=1,41182,68490

But I agree with Hesh. Under finish, it will probably be dark enough that it doesn't really draw the eye that much, whereas with the strip it will be highlighting the difference as a feature.

And anyway, it's a lot less jarring to my eyes than bookmatched curly woods where the curl inverts at the centerline, and people do that all the time.

I agree with the others that suggest to leave it as it is. Wood should look like wood, not like HPL.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

I've done them on closed boxes before. Clamp a straight edge, use a square base router, and rout in the direction that pulls the bit into the straight edge. I glue the strip in with superglue.

I've done a few after closing the box. Here's one.

I use a 5mm thick (3/16") perspex straight edge taped down with heavy duty double stick tape (the carpet variety) and a router with an adjustable fence to run against it. Use a router bit narrower than the intended inlay, say 1/8" for a 1/4" inlay. It's the first cut that will wander if any does and with a narrow bit you can straighten the groove out as you widen it. I leave the fit tight and press in the back strip, which, depending on your design, can be trimmed to exactly how tight with a block plane. I prefer gluing in with Titebond. CA has a tendency to turn "white" woods yellow but works fine if no white wood is involved.

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Hey! You guys are right. It will look fine. I did have a set up worked out and it would have gone fine, if I was careful huh Wud. If the jury of peers says leave it, it stays. The wood turns pretty dark with Naptha so it will probably darken up with nitro.



I had no choice with the glue up. I got the set off Ebay and it was already guitar shaped.



Of course Mike. My jointer is well set up.

[quote="jshelton" That wood is called Kamagong in the Philippines. It's pretty, bends well and hard but in my experience it's very prone to checking.[/quote]

Thanks John. Kamagong eh. It is very pretty. The sides look a lot like Mun but a little more purple. It should look very nice under finish. I'll try to post a few photos.

Thanks All

Be absolutely honest , I agree with the Majority .. Looks fine to me.

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

Darn it, now James has me self conscious and looking in the mirror to see if I go from vertical to quartered to flat since I have been called that word before too....

I agree that it looks fine, it is wood after all...

You could tone it down a bit by just lightly shading the one side before putting the final clear on it but don't over-do it. I would just tint the sealer and airbrush it or if you are good you could use a glazing brush to blend it in. I would probably go with the latter myself since I have done a lot of glazing in the past and if done right you would never know it wasn't that close of a bookmatch. The nice thing about glazing is if you don't like it you can just wipe it off.

But again, it is wood and no 2 pieces are ever exact.

Cheers,
Bob

Some good points from James, and yes, I share Hesh's concern. I believe I have been in attendance with aforementioned group.

I could go either way, leave it raw and sexy or put the back strip in. A winner either way!!!

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The reason I asked about the tight joint was because if one was intentionally planning to not use a back strip, the surface finish of the joint is not as incredibly important than if one was planning to rout out a backstrip channel. If it's incredibly flush, then u are set. Sorry if it sounded like I was questioning ur technique.

Mike