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It's a student model cello which is perfect for a student of repair. The guy is breathing life back into it. No one is going to take a $1000 cello seriously anyway. Keep plugging along, you are doing just fine. I'm so glad there was no Internet when i got into this business...

Jut did my glue-up! Hopefully went well. I used 22 clamps.

One thing you might want to consider (next time) doing is making cauls for clamps. For an instrument like that I would have band sawn the outline of the cello into a piece of 1/4in plywood probably about 1' wide in sections. Then line the cauls with cork and perhaps even kerf the caul to fit the irregular shape of the cello edges. Cauls are good for distributing pressure and for not marring up the surface with clamps.

You had mentioned surgical tubing before. That is actually what I would have used. Well, actually, what I use is rubber made from tying old bicycle tire tubes together. I have a section that is probably 50ft long and use it for clamping backs on my guitars.

I hope there is no "next time" for OP.

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"Act your age, not your shoe size" - Prince

Good job saving this cello, Robert.

We all have to start somewhere, Chris! Though that “hide glue” did look suspiciously woody to me...


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I was all set to use the tubing but chickened out due to not knowing if I would be able to get everything positioned and strapped down before the glue set. Clamps are easy I am familiar with them. Several luthier videos that I saw showed guitar makers using rope and rubber for attaching bodies to ribs. Also those red clamps have swivel heads and the DeWalt clamps I put right on the edge to the extent possible. All the clamps have rubber feet and I tested a small area before overnight with no surface marring at all.

We'll see how this goes I'll leave it clamped until tomorrow and then another day without clamps. Then I'll touch up the raw spots with new varnish and put the cello back together and see how it sounds. I marked the previous sound post position before I assembled it so hopefully I am able to get that back into the same location.

Thank you! Not sure what I did that was so bad was it the DeWalt clamps? I took the top off, I am pretty sure they are designed to do that. Fixed the damage and put the top back on. What would a luthier charge to do for what I did?

Yes, we do. But most folks seek knowledge before diving into the deep end. And these days, there is plenty of info out there. OP didn't even look until coming up for air twice.

Woodworking is NOT the same as luthiery. I had idiots walk into my shop back in the day and think because I did guitar repair, I could also make and install cabinets in the kitchen for their wife. I set them straight right then, in no uncertain terms.

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"Act your age, not your shoe size" - Prince

Not sure what you want from me. I watched several videos and read a few luthier blogs. I removed the top per what they said. Yeah a little wood came off with the glue but not much I fixed it with under a 1/2 mm of putty. Is it the DeWalt clamps that are bothering you?

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Anyway I can't really find Varnish anywhere it would seem most luthiers make their own. But looking at the ingredients it looks like mostly shellac and linseed oil. So I'll just mix them and add a little color and see what I get fixing the separation line. I found an exact color match in stain and already tested it on the Cello (see below) and it is near perfect. I think I can refinish the crack and the few dings fairly well with it.

Do you have pictures of the finish area you're talking about repairing? Is it just the little scuffs I see in the first picture? Are the dark spots your color matching, or?

Would a cello of this caliber have a varnish finish? Or would it more likely be a poly of some sort?

Provided its not a lacquer or varnish and you've already got the color matched, you could just use some CA glue to fix the finish cracks.

As we pointed out, you should have removed THE BACK. The OFL isn't just a collection of doofuses like most internet sources. Some of us know what we are doing, and have done that for a long time.

You could have come here first and asked before you ever touched the thing, and we would have gladly shared our knowledge with you. But you came later when you had doubts, and even then you questioned some of us.

I was serious when I said don't do repair again. You are obviously a slow learner, so go back to whatever else you were doing. I don't feel the need to treat everyone with kid gloves, and make no apologies.

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"Act your age, not your shoe size" - Prince

Ha pile it on I can take it I thrive on negative criticism. Well, actually yours is just negative, but still I can take it. I listened to all the advice I got here and took much of it. On the glue type and clamp up, etc. I was ready to use hide glue. The top was already off before I posted. And again, it was the top that had separated and the tailblock that had cracked. How would I fix that without removing the top? I also asked how much you, as a professional luthier would charge for this repair?

In any case, I am looking to expand my woodworking skills and thought I might try my hand at making a violin.

I misspoke. None of the finish is cracked. It is really just cosmetic touch ups. The small areas I am talking about are the picture where I put a puddle of stain which is where the tailpiece (that the strings attach to) scratched the top. When I wiped it off it turned into the above picture. See below for the before pic. The other areas are just nicks here and there. But the main area I am talking about is the separation point between the top and the ribs. That area between the top and the ribs will need a bit of refinishing on it. But good point I am actually not sure what they finish these with it could be poly. The Cello is considered a decent student Cello (Cremona). Cost new for it is around $900.

Shellac would be an acceptable touch up no matter what the original finish is.

I wouldn't worry about the finish repair too much if it was mine. Other than the value gleaned from the learning experience repairing what's in your picture won't add much value to the instrument. In my opinion the scars of living are all part of it.

In regards to where the top separated from the sides, I guess I'd be hesitant to use CA glue for that, as that could cause issues in case of having to do possible repairs in the future.

This is a good point about the useage scars. I would never put CA glue on the Cello.

I took off the clamps this morning and everything is very solid. I did put some stain in the raw areas and it made a big difference. One could hardly tell the top had ever been off. I tried to put the sound post back in but kept dropping it in the Cello and had to fish it out (PITA). I got a special tool for it but it's not easy! I'll try again later. I think also I will string/set up the Cello later today or tomorrow and see how it sounds. I'll have a couple Cello people I know try it and let me know what they think.

Well for practical purposes the Cello is done. It took me an hour to tune it but I think I have it now. It is perfectly tuned (according to my Snark) so I'll check every few hours to see if the tune holds. That wood piece that goes in the bottom where the metal stands comes out of wants to go at a slight angle. So I had to let that find its sweet spot and now it seems more stable. That part is also under a lot of stress with the strings constantly pulling against it. I am actually surprised more Cellos don't break at that point.

Looks great to me. Good job!

I agree. Well done.

I'll guess you've looked at a bowed instrument forum or two, and perhaps that has helped your patience with us guitar mechanics. If you haven't, here are a few areas where their advice might have differed: I believe it's still pretty common to remove the top rather than the back when repairing bowed instruments. The top/rib joint on a cello is very different than the same joint on a guitar. It's designed to be easy to open, and on the better grade instruments, it is lightly glued for the same reason. What we call an "end block" is usually called a "bottom block" on a cello. Also, Titebond is an excellent glue, and a good choice for this repair, but I think there's more prejudice against it (and against us guitar mechanics) in the serious bowed instrument crowd. I like to use a piece of folded bath towel saturated with hot water, inside a large ziploc bag as a hot water bottle for heating parts before, during, and after hide glue assemblies. Less chance of blistering a finish, or drying out a plate until it cracks.

More clamps would be good. Spool clamps are easy and cheap.

The repair looks great. You've returned a cello from the dust bin to go on making music. I hope it inspires some young player. Thanks for posting.

Well so there ya go, it looks like a cello again!



Great idea, I'm going to have to give that a try next time.

I beg to differ. For violins and cellos, removing the top is a lot easier and more sensible, given that removal of the back implies (trying) to unglue the neck button from the heel, which is a pretty complex and potentially destructive procedure.
I've never seen or heard of anyone purposely remove a violin/cello back instead of the top to gain access to the cavity.

Good job and good save on the poor cello, Robert.

I think someone owes Robert an apology.

It is certainly true that Robert now has more cello repairing experience than many of the people who have been offering advice here (myself included).

And I disagree as well but not with what you may think.

Chris is a veteran repairman who's been in the trenches for decades. He's seen the ravages and the destroyed instruments that result when folks well intentioned or not do repair work without any experience or being properly tooled up as well. After a time we, those of us who work in the trade become very averse to the DYI crowd especially when flipping or making a buck is the motivation.

Dave and I would be happy to relate to folks how seemingly daily now someone climbs the couple flights of stairs to our... tower of song (RIP Leonard Cohen) and exclaims "look at what I just WON... on eBay." Then we end up being the ones to tell them that it's a forgery, it's in need of a neck reset, it's been materially misrepresented, or a thousand other things that sellers fail to come clean on with buyers.

Tuesday a young man picked up his multi thousand dollar guitar that we are denying him service on because he lied to us AND someone else did prior terrible work on using unserviceable methods making future repairs a matter for the factory now. When we triaged the instrument I noticed the prior horrible repair attempt that actually will now prevent the proper repair and instead this instrument will need a complete top refinish and it's a burst too.... What was a simple repair that could have been done in 20 minutes will now take months....

After his denial of tampering with it he fessed up when I pressed and I do press when my gut tells me someone is misrepresenting... and admitted that his friend squirted God knows what kind of glue in there and set weights on it to clamp it. What resulted was ruined binding, chipped finish, glue that will not respond to being cleaned off the front of the guitar and a discussion with the factory by yours truly.

I told the factory that I am denying him warranty coverage and why and they completely agreed with me and thanked me for being their "eyes and ears" in the field. This maker has a superb warranty and will usually error in favor of the client. But this is only possible if the misrepresentation and fraud is also weeded out so that this very fine warranty can be available for folks with genuine warranty claims. The factory took notes and contacted the client and suggested that he pick it up from us (and shut the heck up while doing so since I was already pissed at him...) and send it to them. They offered to keep his warranty coverage in tact for all other things in the future but this repair would have to be paid for by the client and will cost a large percentage of the price of a new instrument. The ETA will also be 4 - 6 months.

This is what can happen when someone hacks into repair work with no experience or to make a buck or both. None of this is offered specifically as suggesting the OP as a hack or a flipper or whatever. That's not the point I am making.

I'm just sharing that stuff happens when musical instrument repair is done by even well intentioned folks who lack the experience, tools, knowledge, etc and/or are motivated by either a lack of respect for how instrument repair is properly done or by a profit motive.

It's not uncommon for us to receive DYI questions and we won't go there. When we do approach the idea of a hobbyist doing repair work on other people's valuable personal property we are all about disclosure to the client/victim.... that the repair person lacks experience and outcomes will be unpredictable. There is also the idea of a clearly billed "project guitar" too but that's a different, slightly discussion.

After seeing hundreds of poorly repaired guitars if not thousands I understand how Chris feels and have to admit that when I first read this thread I was SMH (shaking my head) too.

FYI as well there are two major divisions in the repair Luthier world. The plucked instrument crowd (us....) and the bowed instrument crowd (not us).

Most professional plucked instrument repair people and vice versa will not venture into the other world for a number of reasons that include honesty..., integrity, respect for the instruments, understanding that the training and experience is very different and an ego that's kept in check or at least tempered by an aversion to unwanted liability and having to buy a POS instrument that you may have just ruined.... In the age of the Internet this is even more critical to know your own limitations and be keen to not breath your own air instead being an adult in the room and respecting the valuable personal property of others.

With the two divisions in repair Lutherie considered I don't think that anyone here is qualified with a decent amount of bowed instrument experience to comment on this repair on a cello. Ernie perhaps but he's the only one I know here who may be qualified. I'm certainly not and would say so up front if asked and I do say this when I am asked every few weeks.

And really lastly there is a major reason why working in the trade pros avoid this forum and it's in play here. When we comment from honesty and experience someone gets their feelers hurt and/or someone else may get offended. Chris never intended to insult anyone but he was showing clearly a lack of respect for people that do not respect that this trade does require years to learn to do well WITH the scrutiny of others and not just repairing a few in your basement. This trade also requires as humbling as it may be one to understand that we have to at all times do no harm to these instruments that we are fortunate enough to have been asked to repair. It's important and Chris knows this as do I.

To the OP this was never a bowed instrument repair forum and it's barely even a guitar repair forum as most of the pros are not participating here regularly. I appreciate that you did ask for assistance, that's great and was a good idea. This as you discovered was just not a very productive place in so much as you did not receive much in the way of help specific to a cello.

My hope is that when you promote this cello for sale that you will disclose that you did some repair work and did your best and it's probably not going to be an issue. But I would disclose that it's had repairs and even that you are not an experienced cello repair person. Of course this is completely up to you. It's also the reason why my shop does not and will not give DYI advice to anyone. We cannot know at the end of the day how ethically someone will approach any resulting selling of the instrument. Food for thought perhaps.

I'd like to meet my friend Chris in person one day and get drunk and exchange war stories of all the hacked up stuff that we've seen. I would also ask others here, my friends too to please cut Chris some slack he is representing a point of view that I not only share but many of Chris and my peers who work in the trade would be and will be shaking their heads too when they read this thread.

Looks like things turned out pretty well though and that's what's important.

Thanks everyone.