Repairing a chipped and cracked stock [DIY Home Gunsmithing]
Posted: Wed Sep 04, 2019 9:24 pm
Earlier this year I rediscovered a old Indian Hume Pipe (IHP) made National Hämmerli Cadet CO2 Air Rifle. It had been lying with me for many years, pending a restoration, which I never got around to. This one had belonged to my cousin (my own childhood Cadet rifle was lost more than 2 decades ago) and he had given it to me as a DIY project in return for a BSA air rifle he usurped from me! 
Anyhow, I decided it was high time I got around to getting this old air rifle working. From the condition of the rifle, it was evident that my cousin had put it through some serious abuse. Amongst other things, the condition of the stock was terrible, see photos below:-
NOTE: Photos are posted using share link from google drive, so you can simply click on the top right hand corner of the photos to open full size versions in a new tab.
BEFORE PICTURES
Left Hand view of stock showing chipped and cracked portion towards the fore-end
Close up of chipped portion of left hand fore-end
Inside close up of chipped & cracked portion of left hand fore-end showing extent of damage
Close up showing extent of crack in the stock
Right hand view of stock
Close up of chipped portion just front of where the bolt rests
Really poor condition, but salvageable, so I decided to start the restoration/ repair work by fixing and refinishing the stock.
SOME ITEMS/ TOOLS USED
Small pack of sawdust I saved from when I fitted a Rink (walnut) grip to my wife's Morini 10m target pistol
Mixing epoxy (Araldite) with fine walnut sawdust. You can also mix in some powdered wood colouring in stead of sawdust, the idea is to blend in the epoxy colour with that of the finished wood, as closely as possible.
Some of the various kinds of files used during the repair
WIP PICTURES
1. First we must get wood splinters/ veneer/ something similar in the same shape as out damaged (chipped) areas. These are applied for purely cosmetic reasons and if looks don't concern you, you can simply fill in the chipped portions as well as the cracks with epoxy resin or epoxy resin mixed with sawdust or colour (for at least some match to the rest of the stock).
Since I have a lot of scrap wood lying at home, from some carpentry work done in the past (and this is not exactly a high end/ fine gun) - I chose to simply use splinters from those for the repair.
For best results one should ideally use as exact a match of the wood (of the stock) as possible. For an almost exact match, you would be best advised to scrape of a small shaving (using a v chisel) from a portion of the stock not visible externally - for example, the barrel groove or under the buttpad. Just make sure the shaving is done along the grain for as close a match as possible.
Close up of chipped portion of left hand fore-end, AFTER I gouged it some more using a wood carving tool (v shaped small chisel), to make it more uniform and thus easier for me to fit in a wood splinter.
Various scrap wood chips laid against tracings of chipped (damaged) portions of stock to check for best fit/ cutting into approx shape
2. Now we need to epoxy in the wood splinters (for aesthetics) and fill in the cracked portions with epoxy (for a strong bond). With Araldite it is best to allow it to cure for at least 48 hours before proceeding to the next step.
Close up of right hand side chip being repaired by epoxying in a small splinter of wood.
Cellotape "dam" applied to both inside and outside of the right hand repair, to prevent the epoxy from flowing everywhere and also to allow me to "build up" extra epoxy around the repair.
Inside view of the above mentioned cellotape "dams"
Front portion with wood chips epoxied in (epoxy+sawdust mix). I also applied generous amounts of epoxy to the inside chipped portion and inside the crack, before binding the cracked portion with an old cycle tube.
View from front of the above repair, showing the epoxy flowing on the inner side of the repair
Overall view, some of the tools used can be seen lying around
Front portion being taped up, to prevent the epoxy from flowing all over the place.
Another view of the Front portion being taped up, to prevent the epoxy from flowing all over the place.
Front view of the taped up Front portion, in this one you can make out just how "proud" the epoxied in wood chip is sitting (will mean more sanding later, but hopefully will cover more damaged area).
Now we wait for 48 hours
Inside close up of right hand (inside) after removal of cellotape "dams"
Outside close up view of right hand (inside) after removal of cellotape "dams"
Another close up view of right hand (inside) after removal of cellotape "dams"
Close up front view of fore-end repair after removal of cellotape binding
Close up front left hand side view of fore-end repair after removal of cellotape binding. Notice how the epoxy has flowed all over despite being bound by cellotape.
3. Now on to sanding down the "proud" bit to make them flush with the rest of the stock. For initial (heavy) sanding the parts which were really jutting out, I used second cut files, then as I got closer to the actual stock, I switched to a sanding pad (actually a large eraser) wrapped with 200 grit sandpaper.
Close up of right hand (inside) after initial sanding has revealed a small air bubble in the epoxy
Above air bubble filled with a small dab of epoxy + sawdust
Close up of left hand (front) after initial sanding has revealed a small gap which the epoxy was unable to reach or (more likely) left behind when the epoxy flowed/ settled
Above gap filled with a small dab of epoxy + sawdust
Now we wait another 48 hours
4. Sanding down recommences.
Close up view of right hand (outside) after sanding down repair
Close up view of right hand (inside) after sanding down repair
Close up view of right hand repair from another angle, after sanding down
Close up front left view after sanding down repair. The crack line behind the epoxyed in wood splinters is barely visible and looks like it will be a strong repair.
5. Now to give it a nice oil finish! I followed Mack The Knife's advice from this excellent thread - viewtopic.php?f=22&t=1366
A minor disaster while sanding the stock prior to applying the oil finish. Three small splinters broke off just around the hole for the main screw which holds the action to the stock. However, I was able to locate them and epoxyed them back in. In the final (post finish) photos you will see how much difference exactly matching wood can make, as this repair is almost invisible, unlike the other places where I simply used scrap wood.
So after another 48 hours break, the sanding continued (up to 600 grit), till I was satisfied and began with the oil finish application. I used Birchwood Casey's Tru oil, but I have seen double boiled Linseed oil on sale at amazon's India site, one can use that as well.
AFTER PICTURES
Left Hand view of stock after final coat of oil finish
Close up front left view after final coat of oil finish, showing the repair in detail. Not too bad even though scrap wood was used.
Close up front (inside) view after final coat of oil finish
Right hand view after final coat of oil finish
Close up view of right hand after final coat of oil finish
Close up TOP view of right hand after final coat of oil finish. If you look closely you can see how the cellotape "dams" helped build epoxy (the dark portions visible) around the repair, thus giving it much more strength.
Bottom view of stock after final coat of oil finish
Close up bottom view of stock after final coat of oil finish - showing portion around bottom stock screw where those three small splinters of wood were reattached using epoxy. As you can see, the repair is almost invisible.
Top view of stock after final coat of oil finish
Cheers!
Abhijeet
Anyhow, I decided it was high time I got around to getting this old air rifle working. From the condition of the rifle, it was evident that my cousin had put it through some serious abuse. Amongst other things, the condition of the stock was terrible, see photos below:-
NOTE: Photos are posted using share link from google drive, so you can simply click on the top right hand corner of the photos to open full size versions in a new tab.
BEFORE PICTURES
Left Hand view of stock showing chipped and cracked portion towards the fore-end
Close up of chipped portion of left hand fore-end
Inside close up of chipped & cracked portion of left hand fore-end showing extent of damage
Close up showing extent of crack in the stock
Right hand view of stock
Close up of chipped portion just front of where the bolt rests
Really poor condition, but salvageable, so I decided to start the restoration/ repair work by fixing and refinishing the stock.
SOME ITEMS/ TOOLS USED
Small pack of sawdust I saved from when I fitted a Rink (walnut) grip to my wife's Morini 10m target pistol
Mixing epoxy (Araldite) with fine walnut sawdust. You can also mix in some powdered wood colouring in stead of sawdust, the idea is to blend in the epoxy colour with that of the finished wood, as closely as possible.
Some of the various kinds of files used during the repair
WIP PICTURES
1. First we must get wood splinters/ veneer/ something similar in the same shape as out damaged (chipped) areas. These are applied for purely cosmetic reasons and if looks don't concern you, you can simply fill in the chipped portions as well as the cracks with epoxy resin or epoxy resin mixed with sawdust or colour (for at least some match to the rest of the stock).
Since I have a lot of scrap wood lying at home, from some carpentry work done in the past (and this is not exactly a high end/ fine gun) - I chose to simply use splinters from those for the repair.
For best results one should ideally use as exact a match of the wood (of the stock) as possible. For an almost exact match, you would be best advised to scrape of a small shaving (using a v chisel) from a portion of the stock not visible externally - for example, the barrel groove or under the buttpad. Just make sure the shaving is done along the grain for as close a match as possible.
Close up of chipped portion of left hand fore-end, AFTER I gouged it some more using a wood carving tool (v shaped small chisel), to make it more uniform and thus easier for me to fit in a wood splinter.
Various scrap wood chips laid against tracings of chipped (damaged) portions of stock to check for best fit/ cutting into approx shape
2. Now we need to epoxy in the wood splinters (for aesthetics) and fill in the cracked portions with epoxy (for a strong bond). With Araldite it is best to allow it to cure for at least 48 hours before proceeding to the next step.
Close up of right hand side chip being repaired by epoxying in a small splinter of wood.
Cellotape "dam" applied to both inside and outside of the right hand repair, to prevent the epoxy from flowing everywhere and also to allow me to "build up" extra epoxy around the repair.
Inside view of the above mentioned cellotape "dams"
Front portion with wood chips epoxied in (epoxy+sawdust mix). I also applied generous amounts of epoxy to the inside chipped portion and inside the crack, before binding the cracked portion with an old cycle tube.
View from front of the above repair, showing the epoxy flowing on the inner side of the repair
Overall view, some of the tools used can be seen lying around
Front portion being taped up, to prevent the epoxy from flowing all over the place.
Another view of the Front portion being taped up, to prevent the epoxy from flowing all over the place.
Front view of the taped up Front portion, in this one you can make out just how "proud" the epoxied in wood chip is sitting (will mean more sanding later, but hopefully will cover more damaged area).
Now we wait for 48 hours
Inside close up of right hand (inside) after removal of cellotape "dams"
Outside close up view of right hand (inside) after removal of cellotape "dams"
Another close up view of right hand (inside) after removal of cellotape "dams"
Close up front view of fore-end repair after removal of cellotape binding
Close up front left hand side view of fore-end repair after removal of cellotape binding. Notice how the epoxy has flowed all over despite being bound by cellotape.
3. Now on to sanding down the "proud" bit to make them flush with the rest of the stock. For initial (heavy) sanding the parts which were really jutting out, I used second cut files, then as I got closer to the actual stock, I switched to a sanding pad (actually a large eraser) wrapped with 200 grit sandpaper.
Close up of right hand (inside) after initial sanding has revealed a small air bubble in the epoxy
Above air bubble filled with a small dab of epoxy + sawdust
Close up of left hand (front) after initial sanding has revealed a small gap which the epoxy was unable to reach or (more likely) left behind when the epoxy flowed/ settled
Above gap filled with a small dab of epoxy + sawdust
Now we wait another 48 hours
4. Sanding down recommences.
Close up view of right hand (outside) after sanding down repair
Close up view of right hand (inside) after sanding down repair
Close up view of right hand repair from another angle, after sanding down
Close up front left view after sanding down repair. The crack line behind the epoxyed in wood splinters is barely visible and looks like it will be a strong repair.
5. Now to give it a nice oil finish! I followed Mack The Knife's advice from this excellent thread - viewtopic.php?f=22&t=1366
A minor disaster while sanding the stock prior to applying the oil finish. Three small splinters broke off just around the hole for the main screw which holds the action to the stock. However, I was able to locate them and epoxyed them back in. In the final (post finish) photos you will see how much difference exactly matching wood can make, as this repair is almost invisible, unlike the other places where I simply used scrap wood.
So after another 48 hours break, the sanding continued (up to 600 grit), till I was satisfied and began with the oil finish application. I used Birchwood Casey's Tru oil, but I have seen double boiled Linseed oil on sale at amazon's India site, one can use that as well.
AFTER PICTURES
Left Hand view of stock after final coat of oil finish
Close up front left view after final coat of oil finish, showing the repair in detail. Not too bad even though scrap wood was used.
Close up front (inside) view after final coat of oil finish
Right hand view after final coat of oil finish
Close up view of right hand after final coat of oil finish
Close up TOP view of right hand after final coat of oil finish. If you look closely you can see how the cellotape "dams" helped build epoxy (the dark portions visible) around the repair, thus giving it much more strength.
Bottom view of stock after final coat of oil finish
Close up bottom view of stock after final coat of oil finish - showing portion around bottom stock screw where those three small splinters of wood were reattached using epoxy. As you can see, the repair is almost invisible.
Top view of stock after final coat of oil finish
Cheers!
Abhijeet
