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General Category => Tutorials, Techniques and Tips => Topic started by: George Sansom on December 29, 2012, 06:04:33 pm
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Hi folks,
I'm looking to do one or two easy portraits.
I'm not sure what the best material is to use, perhaps 1/4 ply?
Any tips gratefully received, many thanks.
George
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Hi George, I usually use 1/8 inch Baltic Birch. Sometimes 1/4 inch BB. I cut all of my portraits stacked 3 or 4 high and use #1 FD Spiral blades. Hope that helps
Don R
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Hey George, for best contrast, most folks use 1/8" or 1/4". Most folks use Baltic birch plywood, but any good quality hardwood plywood will be fine. For best cutting results, stack layers to achieve at least 1/4" thick. This will give you better control of your workpiece and will give you more than one copy. If you don't need more than one copies, use a cheap plywood to make up the thickness.
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Thank you guys, much appreciated.
George
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OK...I do mostly portrait type cuttings. My procedure is to 'stack cut' any where from 3/8" to 5/8" thickness of stacked BB plywood.
Most often it is 1/8" pieces with an ocassional 1/4" piece.
When I look at my pattern I will go to my stack of wood and try to select wood that has a grain pattern that is in keeping with the pattern itself, either vertical or horizontal and fits with the theme of the pattern. Sometimes I will 'reverse' a piece in the stack so that the final cutting will be a mirror image of the cutting (put the back side up in the middle of the stack).
The bottom piece of wood is always what I consider a 'throw away' piece since I use only 2/0 spiral blades and that piece will have the worst of the 'fuzzies'. Most often I am able to sand and file those 'fuzzies' off and still use the piece (a bonus, if you will).
All pieces are sanded to at least 220 grit on the 'face' and 150 on the back before starting.
After cutting I soak the pieces in the famous BLO mixture for at least 10 minutes and then allow them to dry 12 -24 hours. The backer I use is chosen the same way as the the wood itself and is in keeping with style and subject matter of the portrait. It may be stained oak plywood, heavy 'scrapbook' paper or frabric, mostly felt.
When making my 'stack' I simply clamp the boards, tape the edges with painters' tape apply my pattern to the top board with 3M77 spray adhesive and then cover the whole pattern area with packing tape.
In the cold months, like now, I bring my precut plywood INSIDE and allow it to come to room temperature before making the stack and applying the pattern. If I don't finish the cutting in a single sitting I bring the piece inside to stay at room temperature until I go back out and heat up the shop and start cutting again. This prevents wide temperature swings of the wood.
It works well for me!
~~~GB~~~
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Very interested in doing portraits someday.
Do you sand fuzzies before separating the stack to take advantage of the strength?
Forgive the stupid questions, I'm new ::)
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Personally, I sand mine after and use a combination of sanding and burning with my Zippo lighter
Don R
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Hmmm Don, now burning the fuzzies off is something I've never thought of. Thanks for that tip. It just might be worth a try. Always nice to learn something new.
Mike
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Mike, remember not to burn too long, it's only the fuzzies you want to burn not the whole project ::) ::) :o :o :D :D :D (sorry couldn't resist )
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Ya saw a tip awhile back about burning off the fuzzies on the back. I always just sanded and filed them off before but burning works great and cuts down on sanding and filing needed. And yes you need to be careful to not burn too long to try and keep it from getting too dark. :)
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And I also have to ask GrayBeard, what is the famous BLO mixture? You have me stumped on that one
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That would be Boiled Linseed Oil and Celulose thinners mixed 50/50 (I believe you Americans use mineral spirits instead of celulose thinners)
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Right on the mark, Keefie!
Boiled Linseed Oil mixed with and equal part of Mineral Spirits (paint thinner) and placed in a mason jar, not plastic jug or container.
I have a cheap 'sheet cake' pan I got at a Dollar store and I simply pour the BLO mixture in that,then lay my pieces in to soak for about 10 minutes.
Remove from the BLO mix, shake off the excess and place on a cheapo kitchen cooling rack to dry overnite. As they are drying be sure to continue to wipe off any of the mixture that may remain on the wood or it will leave you with a sticky mess. Pour the mix back in the jar and seal.
Then I hit the piece with a few coats of satin Lacquer (spray) and sand between coats with a piece of paper grocery bag. I personally don't like glossy finishes on most of my projects...
As with most of the tips and tricks presented here, this is the way I do it and not necessarily the only way it can or should be done! It works for me!
~~~GB~~~
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Thanks guys. I will have to give that a try. I havent done that on any of mine that I have done.
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In thinking this over, I tried an attachment for my rotary tool to get rid of the fuzzies on the back of my stack cut copies of my recent portraits and was very pleased with the results. It took me only approximately 40 to 50% of the time as usual to get rid of them. I'm sure that I'm not the first to try this, but I've not seen it mentioned here before. I just ran the tool attachment along the back edge of the cuts, and voila, the fuzzies were quickly removed.
Mike
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In thinking this over, I tried an attachment for my rotary tool to get rid of the fuzzies
I imagine you need a steady hand and a keen eye to do this, especially around the more fragile areas. A steady hand and a keen eye are something I no longer possess. I'm still going to give it a try, but I have a feeling my last subject will end up with a blank look on their face. :)
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I never tried that one Mike, I thought it might be too aggressive. I will have to give it a try.
Don R
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When you use BLO do you have any trouble getting the backer board to adhere? What do you use for glue?
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After the project is finished I apply it to the backer by turning it face down, put some Alene's Tacky Glue in a plastic lid (like a butter tub) and 'paint' the glue on the back of the project and then place it on backer. Then I take a piece of 3/4" plywood and place it over the top, weight it down with a gallon can of paint and let dry for about 2 hours.
I have never had any project separate using this method even with the back coated with the BLO mix or any other finish.
~~~GB~~~
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That's exactly what I do GB, except I use bricks to weigh it down!
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Dan...your hands are younger than mine....paint cans have handles and bricks don't!!!
~~~GB~~~
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Maybe a small alcohol lamp would work, I use one to remove the small thread tags on windings when fishing rod building.
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I do it pretty much the way GB does. Other than the bottom board being a throw away I also use a throw away board for the top. Could be anything, poster board, laun board (door skins) scrap ply, anything that works. That way you don't have to mess with the pattern at all.
One more little hint. Remove the fuzzies by fire before you use the BLO-Mineral Spirits . Don't ask..:):):)