OzFclass

Was just wondering if anyone had any designs for a half decent fclass timber stock? I scored a nice slab of peppermint which is hard and has a very nice grain.

Peppermint is not a good idea as it will crack in time after you shape it

It's been properly dried for 13 years.

mick6220 wrote:13

Bad luck.

Is it a bad choice do ya think? The bloke I got it from has made a few stocks out of it.

If the piece of timber is thick enough to cut down to strips and glue back together, this will help to strengthen the stock from cracking and twisting over time.
If you have time please have a look at some stocks I've made in the past by laminating 5 pieces together.
gunstockz.com

Laminating the stock is a good idea. Ideally, if you are not laminating a stock, then you want quarter sawn timber to minimise its shrinkage. A quarter sawn stock must be cut with the grain in the horizontal. It is not as pretty because the grain lies horizontally. You can see this by looking at the end of the forend. You don't want grain that is vertical (even if it is quarter sawn) or diagonal. It depends on whether you want pretty or stable. Also the take down screws pull down through the layers of a horizontally quarter sawn stock and add support to the structure on tightening. Conversely, if the blank is not quarter sawn with horizontal grain layers in the forend, then any tightening of the screws tends to split the cell structure of the timber and interferes with resonance. Good vibrations just like a quality violin give better accuracy. For resonance and weight the density of the wood needs to be about 33 inch pounds fully cured. e.g. some walnut, blackwood, or Queensland maple and something that does not have a short grain structure, sapwood or heartwood. So depending on the tree, and depending on which part of the tree that is used, and how it is sawn for the blank it will all effect the stock's stability and resonance.

If you want to select a quality blank, then the best walnut or blackwood can offer a quarter sawn grain in the forend yet twist or fiddle in the butt area. To get this type of blank I have cut them from the base of the tree for good looks. These are why these top blanks are so dear. But practically speaking, timber for ease of sawing and working and in terms of stability is better 6 feet from the base of a mature tree. The timber needs to cure properly and it cures at a rate of 1" a year with the ends of the blank painted or sealed. This allows for the woods cell structure to cure evenly for that resonance we desire. Kiln dried timber damages subtle cell structure and never has that mellow tone. If the wood is not cured then putting the router into the dryer sections will lead to stock warping if the stock is exposed to the sun because core moisture moves out to the dryer sections. Of course the stock needs to be sealed. If you are not using the Birchwood Casey True Oils then I suggest for the first coat you apply varnish or polyurethane that has been diluted with mineral turpentine 50% to allow it to penetrate into the wood.

If you have a wooden stock then the takedown screws should not exceed the wood density because you are then crushing the wood cells and make it prone to movement in changing humidity. This is particularly bad if the stock travels by air. If you use an aluminium block and you want 50 - 60 lb takedown pressure then the block should extend through to the underside of the stock where the takedown screws should bear directly against a washer which bears against the block. There should be no wood sandwich but a bed of solid washer much like a pillar bed through to the aluminium block. Pillar beds in their own right achieve similar results but don't stiffen the stock to prevent any movement.

I guess aluminium or carbon stocks are stable and many wooden stocks are deemed otherwise. Maybe wooden stocks are less desirable because people didn't have grandfathers to show them what to look for and how to do it.

Hope this helps.

David.

David, that's a really interesting read, thanks for imparting your wisdom.

How would a stock made from laminated planks of kiln dried Tasmanian Oak go? It is a very common easy to get timber that is a bit plain but very durable. What is a good glue to laminate with? I find that Aquadhere can stay a bit rubbery and difficult to sand.

+1 Dave

Great info there

I find that Aquadhere can stay a bit rubbery and difficult to sand

DO NOT USE THAT GLUE
2k (pack) or Selleys high stress wood glue

http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&ved=0CFwQFjAI&url=http%3A%2F%2Fbonetimber.com.au%2Fwp-content%2Fplugins%2Fdownload-attachments%2Fincludes%2Fdownload.php%3Fid%3D794&ei=SlI6U9KWBceIkQXtkYGYAQ&usg=AFQjCNGKK90alvDvwQppYWr-3oXSRwvLBA

Thanks Guys, only too happy to pass it on. Footsore, the Tassie Oak you are considering is probably a silver top mountain ash which is really an older mountain ash and marketed as `Tassie Oak. It is darker because it is an old mature tree usually in excess of 100 years. Mountain Ash, is only one of the few Australian timbers that you can steam bend. This is the reason it was used in old sporting equipment, such as tennis racquets. While it can fall in the 33 inch pound density range, my experience with ash as I grow the stuff and worked in a mill over 40 years ago, is that it warps. Laminating it would largely prevent this. However, if you have lots of laminates, the weight of the stock increases a fair bit. It`s a great timber for furniture and framing but put it out in the elements or in dirt it won`t last seven years. It`s useless as a post. The glue we used to use was a hot glue we mixed up and boiled in a billy. Cabinet makers may still use it. Aquadere is useless and any moisture destroys it. You can still get ``Selleys 308 Glue``. Yes, you 7 mm guys it is actually called 308 glue which is a two part mix. It is really strong, water repellant, and mould resistant. I used it 30 years ago to make a duck punt which is as good as the day I made it, and my wife`s old stocks were made using the stuff. These I made with three laminates to keep weight down, with the centre one, wide enough to take the recoil plate and produce the right resonance through the length of the stock. People overlook the value of resonance and that is the only fault I can see with kiln dried stuff. Sure it`ll make a great stock but it may lack killer accuracy. In the old days we did not have tuners to fix this. So on balance, with a tuner, a kiln dried stock would be ok. I remember buying the Missus one of Corby`s aluminium stocks when they first came out. She didn`t like the ping sound it made and went back to her old walnut Muzzie and I scored the Paramount.

Thanks for the advice Dave.

I bought a copy of American gunsmith Richard Franklins book, it contains lots of info on how he did his laminates, and stock making in general, he produced some great stocks, but is retired now
Dave, thanks for all the info, proves the old saying " You cant beat experience" !


DMC