Primitive Archer
Main Discussion Area => Bows => Topic started by: BowEd on January 27, 2017, 11:19:36 am
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I keep a stick here with a large pine pitch ball on it for hafting stone points etc.I was wondering if anyone has used this pine pitch mixed with alcohol to be used as a light dye and even as a waterproofing barrier over top of a sinew layer on a bow.I suppose shellac could accomplish the same thing maybe,although submersed shellac eventually will break down as I don't think pine pitch will.
Seems it's been used to seal cracks on birch bark canoes.It should serve a purpose for water proofing and possibly dye too for a nice light brown color.
Just wondering if anyone out there has tried this already to comment on it's effectiveness.
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Ed, I use pitch varnish(pitch dissolved in alcohol) to seal sinew wraps on arrows and to seal arrows sometimes. I don't think it would work well to seal bows because it is brittle. I imagine if you add oil of some sort(bear grease, tung or linseed oil, to make the varnish more pliable it would work fine.
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Yes I hear you.I imagine over use and time it would chyrsallize on the back of a sinewed bow.It's better suited for use on a stiff unmovable area.
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Better stick to the old Tite bond 3/snake skin or birch bark method for sealing sinew on bows.
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Pat B and I were talking about something similar on another thread, so I decided to do some research and this is what I found a post from a guy that makes violins named Micheal Doran I copied his post and pasted it here, I hope this is ok if not please let me know and I will remove it immediately and summarize and re post. You may have to experiment a little but it should lead you down the right road
This is Micheal Doran for the rest of the post
"I have made quite a bit of oil varnish for my violins, so in that area I have some limited expertise. I have never heard of anyone combining shellac and oil, though that doesn't mean it is impossible. I usually, as I'm sure you do, dissolve shellac in alcohol.
To make varnish I combine cooked tree resin and linseed oil, with or without turpentine.
You can use almost any resin to make varnish, from fresh sap to fossilized amber. Every resin imparts different characteristics to the varnish. I use a kind of copal. Copal is a broad category of partially fossilized resin around 40,000 years old, the age makes it copal not what tree it came from.
I cook my resin at high temperature, 395-400 degrees Celsius. This is to burn off the volatile compounds I don't want in my final varnish and to carbonize the resin so it takes on more color. This process of cooking the resin takes four or five hours, and is smelly and a little dangerous. Outside is the only safe place to cook varnish. I usually cook up a big batch of resin because it it easier to control the temperature.
I then combine small amounts of the (cooled) cooked resin to linseed oil. A 1:1 ratio by weight is a good place to start. I then bring that mixture up to 270 degrees celsius. At his temperature something chemically changes in the oil and it combines with the resin and will then dry properly. This is also near the flash point of linseed oil when it can burst into flame. That has never happened to me or anyone I know. I cook it at 270 for 10-20 min then I let it cool and add turps. 1/3 of the volume of the oil is a good place to start, you can always add more to "taste". Sometimes I filter the varnish through a silkscreen cloth, or you can just let some of the jibs settle for a day or so.
I don't know what temperature you need to heat walnut oil up to for varnish, but I can guess it is in that ballpark range of 270 C."
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Yes and thanks.Sounds like a bit of work there.Infusing linseed oil into the pine pitch.I'll probably just stick with old Tite bond 3 to put a waterproof layer on though.
I was just wondering that's all but thanks for the info.
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I can not comment on the use of it personally, but Hamm and Allely report that a Cheyenne sheep horn sinew backed bow in the Grayson collection at UMO was "coated with melted pitch for waterproofing"
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The reason I like using hard, brittle pitch is because it dried hard once the alcohol evaporates and is not sticky. If you use softer, sticky pitch the resulting varnish will be soft and sticky too. This will eliminate some of the cooking. I do heat the pitch to make it soft when I make pitch glue but usually only use hard, brittle pitch balls to make the varnish.
I may try to add oil and see what happens. The simple pitch/alcohol varnish I use does just what I want it to do, seal sinew wraps on arrows. It seems to work well to seal shafts too but this may keep some fletch glues from adhering.
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My pitch ball has got charcoal and rabbit turds in it.On the stick I can put a finger nail into it so it is'nt rock hard.
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I made some using hard pitch and lacquer thinner. It makes a nice finish but I found it wasn't very strong. If you scraped it on something it would kind of crackle off. That may be because I used lacquer thinner but I found it dissolves the pitch faster.
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I got some incense grade pitch in a trade from someone out west a few years ago that was hard and brittle, all of the turps had off-gassed so it is perfect for varnish, except for trash removal. I've also found hard pitch balls on pine trees here with old wounds. If I collect softer pitch I cook it until it is hard. No thumb nail prints. If I want it more pliable I add bees wax or bear fat to soften it. This way it isn't sticky when cured out, just soft. For pitch glue I also add finely ground hardwood charcoal(from my wood stove). I've used dried rabbit and deer poop but prefer the charcoal. They all do the same thing, add body to the glue.
DC, once the carrier(alcohol, lacquer thinner, turpentine, etc.)burns off(evaporates) what is left is the pitch, which is hard and brittle. Like shellac, it will scratch off. It works for the purposes I use it for. It is a simple method and as per my brain, simple is better! ;)
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Ive waterproofed a sinew bow with spar varathene helsman in a can...looks like satin muscle...gut
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I seal my sinew backed bows with Tru-Oil and a quick spray of satin poly to cut the shine. I usually snake skin back them but use hide glue for that. I have, in the past, used TBIII to seal the last course of sinew on a bow but don't any more.
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I know Chuck has used pitch before for a sinew back water proofing.
I remember him saying he figured it added a lot of physical weight.
I bought some processed pine pitch flakes from a local DIY store.
It made awesome pitch and is pretty cheap for how much you can make
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Ed I mix pine pitch,wax and lard for my natural bow sealer. Heat up the wood and rub it in works awesome. For sealing a sinew backed bow I use more lard than pitch so it absorbs better. Should be the consistency of shoe polish.
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Pine pitch, bees wax and bear grease makes a good leather dressing too.