Repair of an antique desk
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- This topic has 15 replies, 3 voices, and was last updated 7 years, 4 months ago by Hugo Notti.
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20 November 2016 at 3:56 pm #142549
We have a desk from my grandfather, probably around 100 years old. From being pushed to new places every 10 years or so, a few joints have come lose and have to be re-glued.
The desk consists of two drawer boxes to the sides, supported by two thin legs each, a central drawer and the table top. there is veneer on all visible surfaces, so I must be careful.
it seems, that the top is bent a bit, because it requires considerable force to get it down onto the inside front corner of the left drawer box. It fits well everywhere else. I haven’t checked the drawer boxes for square yet, the reason for the bad fit could be there as well.
Now my questions:
What is a reasonable method to losen the glue, that still holds the top? Will a simple hairdryer work or do I need something more powerful? I almost burned a balsa model when using a heatgun, so I am not sure, if I should use one here. And I don’t want the veneer to come lose. I am not sure, if I can get enough glue into the gaps without removing the table top. If you have good ideas on that, please let me know. I am not happy with my plan to reglue almost everything!
What could I do to find out a suitable finish for the surface? I don’t want to redo the whole desk, but the table top looks horrible. I tried a scraper and it works wonders, however, the wood looks different there. Please don’t suggest products, unless you know, that they are available in Germany. I found, that many apparently good products are quite localised or extremely expensive in other areas of the world. I have a bottle of pre-mixed shellack varnish, that I will definitely try. But I am afraid, it won’t last long, because this desk is in use a lot.
I attach fotos of the upper right corner of the left drawer box, inside and front view, and the desk (odd perspective, sorry). You can see the polish there, and tiny areas where I have scraped off some silver marks (paint?)
Dieter
PS: don’t do this at home (standing on a chair)
- This topic was modified 7 years, 5 months ago by Hugo Notti.
- This topic was modified 7 years, 5 months ago by Hugo Notti.
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You must be logged in to view attached files.20 November 2016 at 6:14 pm #142558Hi Dieter,
There is a series of videos showing a whole range of restoration methods on youtube. Just search for Thomas Johnson restoration.
Cheers
Peter20 November 2016 at 8:56 pm #142559Peter, it is an intersting series, but it would take ages to look through all videos in order to find methods to properly disassemble the desk.
In the meantime, I found out, that I can close all gaps with the strength of my arms, so glue might be able to hold everything in place. However, I wonder, if there is something invisible hindering the parts to get together, so I would really like to take off the top. On the other hand, the top is definitely bent and I don’t think, this could be undone.
Dieter
PS: There is a mystery in this desk: The bottom frames of the side boxes are screwed to the back walls and dowels are used on the front of the side walls. They are glued too, so it was not to take them off. The dowels were recessed 3 mm into the frame and then covered with hard resin.
- This reply was modified 7 years, 5 months ago by Hugo Notti.
21 November 2016 at 12:25 am #142566If the desk is that old, it is probably hide glue. Hide glue comes apart with water. You could brush warm water on the joints to loosen them. You can also get an artist pallet knife, from a artist supply place. Its just a thing blade spatula. You can open a bit of the joint, and slide the knife in there to break the bond. Just work it around. I would just clean the surface with gum turpentine and put garnet shellac on it. Will give an antique hue. Follow it with some wax.
21 November 2016 at 7:12 pm #142573Unfortunately, a part of the top has been glued with white glue, I can see some excess on the inside of the joint. Perhaps the left drawer box got lose and was reglued. But white glue is often water-soluble, so your method might work anyway. For safety of the veneer, I will try to work from the inside only. Instead of an artist knife, I will use “japan spatulas”, which are very thin metal too, very similar to card scrapers, except that one side has a plastic cover.
I already ordered some hide glue and checked how to clamp and tie everything together when glueing.
I am not going to take off the veneer on the top, but could that be the reason for the top to bend up? The veneer on top and on the sides is polished and sealed, while the underside is raw wood, where humidity can enter easily.
Dieter
21 November 2016 at 8:10 pm #142584Bob Flexnor has written about the one side finished/onside not issue. He says it doesn’t make any difference. Wood moves. We are so used to particle board, plywood, mdf that we don’t see wood movement.
21 November 2016 at 10:15 pm #142588In the meantime, I remembered an “old friend” on youtube, who does excellent videos on restauration as well. Unfortunately, for many of you, it is in German, and what he says is often even more important than what you can see. I decided, that this desk will become a project here, so whenever something from him is helpful, you will be able to share it. If your German is good enough, look here: https://www.youtube.com/user/tracheide2/videos
David, thanks for the information about the one-sided finish.
By the way, I learned, that hide glue (and other similar glues) work wonders on reparing wood. And furthermore, most of that repairwork can be undone. I might be able to fix some problems on the veneer as well, which was basically shown in one of the videos of Thomas Johnson too.
Dieter
22 November 2016 at 7:53 pm #142617Today, I noticed, that the right rear leg is slightly lose. Turns out, that the rear bottom frame board is split all along its length and this had been repaired before. I can see traces of glue on the surface around the split. The joinery is interesting, but hard to describe. Look at the images. I need some time to take that in completely and understand the functionality.
The split on the fifth image doesn’t worry me. This is just a thin decorative insert that goes all around the drawer box. I will simply glue it together. This insert is damaged on all corners and I will replace the missing parts there. Hopefully, I can achieve a reasonable colour match. But the dark spot near the left dowel is actually missing wood. I think, I want to replace it to support the dowel.
On the second image, you can see the rest of a screw protruding from the tenon of the frame. It has broken, I found the head still in the other frame part.
On image #4, it looks like there were three layers of wood, but it is only two, the brighter piece has a step to form a groove for the bottom panel.
I found no traces of glue where the frame is screwed to the back.
I find new details each time I look at the images (the leg is back in place for now). This is quite interesting. I would really like to take the desk apart completely for further study, but I will wait at least another 10 years before I will do so. And I wonder, how original it still is. I am sure there are a lot of stories to read, but I don’t know, how.
My plan:
Glue the crack in the frame, clean up the remaining glue on the other parts of the frame and then put the leg back in place. I will use glue, where I found glue and I will add glue, where the inside frame is broken. It might be better to replace the inside frame, but I am not sure, if I can do it well, so I leave that for later.
I might not take off the top, but simply reglue the opened areas. I have the desk standing on one side now, and I can align everything quite easily now. I also checked for squareness of all corners and it looks pretty good. The desktop is bent down by 5 mm (1/4″) in the middle, which isn’t visible if you don’t know it. It hasn’t changed when I moved the desk around.
There are some bubbles on the veneer on the desktop, and I will try to fix that with hot water and animal glue. It looks pretty bad now, so I am not afraid to make it worse, I can’t.
Finally, I have to get some good advise for the surface finish of the desktop. I will clean it up completely and it can’t stay that way. I have seen how to make a silky surface with shellack, so I will try that. I suppose, a non-polished silky surface is less vulnerable than a french polish.
Please stop me, if you think, any part of this plan is bad or could be done better without too much skill. I need to fix this desk quickly, because my sisters need it back. So I want to concentrate on the stability and only fix a few things that seem easy enough.
Dieter
PS: The animal hide glue has arrived already, that was fast! Interesting smell 😉
PPS: I recently heard, that the desk had been repaired during or shortly after WWII. A window glass had been broken by an explosion nearby and fell on the desktop. Unfortunately, I don’t know the extend of the damage. The important part of the story was of course the explosion (bomb), not the desk.
- This reply was modified 7 years, 4 months ago by Hugo Notti.
- This reply was modified 7 years, 4 months ago by Hugo Notti. Reason: adding more pictures
- This reply was modified 7 years, 4 months ago by Hugo Notti.
- This reply was modified 7 years, 4 months ago by Hugo Notti.
- This reply was modified 7 years, 4 months ago by Hugo Notti.
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You must be logged in to view attached files.23 November 2016 at 12:40 am #142629If people would do just use hide glue it would make the repairs a lot easier.
23 November 2016 at 8:11 pm #142646Indeed! I consider glueing together a few pieces of pine and experiment on different ways to get them apart without damaging the wood. This desk is part of an ensemble, there is a cupboard, a few chairs and a table as well, so there might be similar work in future.
By the way, can anybody tell, what style this is? I have seen “83 / I”) on several surfaces on the inside, but this could mean anything, perhaps just project number. Of course, it could stand for “January 1883” too.
Dieter
27 November 2016 at 12:25 am #142729Today I started glueing the cracked leg-frame piece with hide glue. I think, I used a bit too much water on the glue, but probably got enough glue remaining in the crack. I just unclamped it and it looks fine now. But I am sure, it will break again eventually, since it has been glued before and broke exactly at the same spot.
This frame part is one piece of wood, by the way. I thought, it was two, but I was wrong. The part, that forms the oudside of the groove to hold the floor panel, has broken off almost completely and needs to be glued too. However, once glued, I can’t put that piece back into the desk. So it must be glued with the piece re-attached to the desk. This is the back rail of the frame, so I will have to come up with a wedging system to press the inside part down while clamping the outside, er, on the outside – against the table top. I will use plastic film to make sure, the wedging does not attach to the glue.
Eventually, I have to make a new piece, but I will wait until my woodworking skills are a more reliable. This job will include removing the veneer from the old part and attaching it to the new one.
Minor task: I have to replace one stopper for the lower drawer, it is gone. The other one fell off when I took off the frame piece.
For a little while, I thought, that the table top had never been glued to the walls completely. But where the gaps are large enough, I could insert a thin scraper and found residue from glue everywhere. This is reassuring, because I already wondered, how this could be stable at all.
By the way, I am taking notes about all interesting details that I find in this desk and I also take fotos. When I am done with my preliminary repair, I might add this for a last post.
Dieter
- This reply was modified 7 years, 4 months ago by Hugo Notti.
27 November 2016 at 7:54 pm #142743I was able to remove the bottom of the drawer box, cleaned it up a bit and repaired two cracks. And the very good news is, that everything can be reassembled as it is, no need to take off the back, so I finished glueing the leg frame part.
I also prepared a strip of mahogany to replace the missing decoration. While resawing, planing and shaping the strip, I got a first idea, why people were ready to extinguish this species of trees. It is beautiful wood and very nice to work with.
There isn’t much left to do on the main structure of the desk. I have to glue in various places, where the original glue sort of disappeared, attach the leg and add two drawer stoppers. I will also replace the decorative stripes (there must be a proper word for that) and give it a light shellack finish. The mahogany should look fine with that, perhaps not exactly original. Then I want to fix some major problems on the veneer too.
Eventually, the damaged parts need replacement, and I also want to refresh the surface finish. But both needs more skill and knowledge.
I will post some more images when I am done with the current repair.
Dieter
4 December 2016 at 11:43 am #143029Apparently, this is a week-end job, probably, because I like the daylight in my workshop. And for the final glue-up I need someone to help handling the clamps etc.
I found an interesting way to fix lose joints, in this case a leg that is glued flat to the bottom frame, secured with dowels and a screw. There was no way to pull it out, and no surface to hammer on, so it stayed put, no matter how hard I tried to remove it. Then I used a flat spatula with hot water to work into the gaps and remove some of the remaining glue. The result: The glue rehardened and the leg is stable again. The final action will be adding more glue into the gaps and rocking the leg, so the glue can soften the original glue and get fill up all space.
Dieter
5 December 2016 at 7:11 pm #143064While unclamping the desk, there were many crackling noises and I almost feared it to fall apart again. It didn’t, but it showed me, that there are considerable forces working against the one-piece-condition. The leg, that seemed stable, is lose again, so I am glad, that I didn’t insert the screw, it might have concealed that. It will be a small extra job to glue it, when I do the other side.
Now I will prepare the other side for glueing. It has no serious damage on the wood, except for a rail at the left inside bottom corner of the right drawer box. I should have had a closer look before I glued the other side, but now I have to deal with it. Anyway, the desk will be in a much better condition when I am done, and I can always start over later, when I feel more confident. Well, it requires quite some force to pull the desktop to the left side of the drawer box (the right one now) and I am not sure, if it is a good idea to leave this stress for the glue. Perhaps some fibres are obstructing the gap somewhere.
Dieter
7 December 2016 at 7:41 pm #143122The desk stands upright again. The right part of the back seam between drawer box and desktop is open, needs to be reglued. But everything else is fine. I will upload a few final pictures soon.
There is more to do, part of the surface is in a desperate state. But I will start a new topic in the “finishing” section.
Dieter
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