Best method to cut ply?

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Thanks, definitely worth trying it this way before I invest in any more saws. I'd rather spend a little more time getting a nice evenly clean cut than risk a faster but splintered and uneven result. This is all new territory for me, and I've got more patience than $.

You are welcome, but which way? Are you trying to make a long straight cut?

I was just in my shop looking for a piece of 1/8" plywood scrap, so I could bother you with more pictures. I think I am trying to work myself up to posting a build thread <grin>. Got distracted by the half-finished rocket sitting on my bench before I found anything suitable in the scrap pile.

Took a look online and that particular one just happens to be one of three that I want to go down in person and check out. This larger one from home depot is another https://www.homedepot.com/p/Vaughan-10-in-Pull-Saw-with-Double-Blade-BS250D/100373697

Yeah -- that link goes to the very blade hanging on the peg board in post #13 . Its pretty much the same saw as the Shark that Dan posted about in post #21 and that sooner.boomer described in post #15. It is a good saw to have, but its not a good choice for the application you describe. Actually, I don't know about the Irwin version but the Shark saw is -- as far as I could tell when I was shopping -- virtually identical to the Bear. Do beware: Dewalt and Stanley both sold the same Ryoba-style saw which was poorly reviewed. But even the good ones aren't good for what you want to do.
 
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Looking at the specs on that saw, it has the same teeth on both sides (at least that's what the web page seems to imply)...

Nope -- the specs are just badly translated on the printed-in-Japan packaging, which bad translation has been copied onto the HD site (and also on Amazon, now that I look there). I took mine down from the wall.

20180107_152445.png20180107_152436.png

The danger of having a computer in the shop is that you can hear the email chime and be pulled away from the fiddly and frustrating work of trying to glue a skin onto an airfoiled fin to the much more gratifying work of telling other people how to do stuff...

Edit: Okay, looking at the picture I see that I have a 250RBD not a 250D. The picture of the 250D HERE looks pretty much like my saw, so I stand by my assertion that the 250D is also a rip/crosscut blade -- but I am prepared to be told that I am wrong.

Now I am turning off the WiFi on this computer.
 
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Ahh, long straight cuts.

Question, does it have to be ply? why not use 1/2" x 1/8" basswood or maple. sometimes some specialty stores will have strips already cut (I'm thinking of model boat builders)

And, to take a trick from my mum, who was an avid quilter. you can get a rotary cutter, it;s like a pizza wheel / cutter, but has a round X-Acto type blade..

https://www.walmart.ca/en/ip/fiskars-comfort-loop-rotary-cutter-45-mm/6000052803667

(I just tried it on a piece of 1/16" ply, and it only took 3 passes.. blade is dull & rusty.. mind you, only the corner of a piece of ply..)

Ply turned out to be noticeably lighter than basswood and I've been unable to find spruce, ply, or any other hardwood sticks in hobby shops/crafting stores anywhere here (and there are only a handful anyway). As I'm just starting to get experience scratch building gliders, I'm beginning to see what works and what doesn't (e.g. a 1/8" balsa fuselage doesn't; it snapped in 2 places when the wings deployed). Two Apogee glider kits I built employ 1/8" ply and they're plenty strong, which is why I went with 1/8" ply (also they're available in sheet form at hobby shops here).

The rotary cutter may work to get the initial cut started so it's easier for another tool to align its blade and finish the cut, but I'm wondering how long and how much effort it would take on 1/8" ply. (I initially tried cutting my ply with an Xacto knife but gave up after 15 minutes when it didn't seem I was making much headway). Thanks for the feedback though. Guess I'd consider a Makerspace studio with a laser cutter if I built several gliders a week but otherwise I couldn't justify the dues. (Dues would probably pay for the right tool that I'd own outright after a few visits).
 
You are welcome, but which way? Are you trying to make a long straight cut?

I was just in my shop looking for a piece of 1/8" plywood scrap, so I could bother you with more pictures. I think I am trying to work myself up to posting a build thread <grin>. Got distracted by the half-finished rocket sitting on my bench before I found anything suitable in the scrap pile.



Yeah -- that link goes to the very blade hanging on the peg board in post #13 . Its pretty much the same saw as the Shark that Dan posted about in post #21 and that sooner.boomer described in post #15. It is a good saw to have, but its not a good choice for the application you describe. Actually, I don't know about the Irwin version but the Shark saw is -- as far as I could tell when I was shopping -- virtually identical to the Bear. Do beware: Dewalt and Stanley both sold the same Ryoba-style saw which was poorly reviewed. But even the good ones aren't good for what you want to do.

Yes, trying to make make long straight cuts with the grain for glider fuselages. And if you do decide to do a build thread re: these saws, techniques and how they can be used to cut what, please let me know so I can subscribe. I'm sure I'm not the only newbie out there that could really benefit from it.
 
How wide are the pieces you need to cut? I'm wondering if a saw is the right way to go. If the pieces you need are less than 1/2" wide, somethingg like a balsa stripper might work better. Example: https://hobbyking.com/en_us/master-airscrew-balsa-stripper.html?___store=en_us

Just need strips 1/2" x 1/8" thick. But is a balsa stripper sharp and sturdy enough to but 1/8" ply sheets? After just needing scissors to cut 1/64" and 1/32" ply, I was caught off guard at how hard and tough 1/8" birch ply really is.
 
Just need strips 1/2" x 1/8" thick. But is a balsa stripper sharp and sturdy enough to but 1/8" ply sheets? After just needing scissors to cut 1/64" and 1/32" ply, I was caught off guard at how hard and tough 1/8" birch ply really is.

Most of them use X-acto-style blades. The advantage is that they are fenced/guided cutters. You can go over the same line *exactly*, over and over, cutting a little deeper each time. You can also flip the sheet of ply over and make the same exact cut (same spacing from edge). You can't cut it in one pass, but I don't think I'd try to cut 1/8" balsa in one pass, either. A larger, more expensive version of a balsa stripper is a cutting gauge.
https://www.marples.co.uk/images/rosewood-gauge3-larger.jpg
The brass wedge is holding a blade that does the cutting. There are also marking/mortising gauges that use pins. Harbor Freight sell one for less than $10. You could get one of them, remove the pins, and add a holder for an X-acto blade.
 
Lastly, with all that's been said, and the time taken, and apparent costs involved for 'the right tool'/ Why not talk to a laser cutter / plans cutter to do them for you? Thinking of someone like laser lizard or even if Madcow would do you some laser cut pieces..

https://laserlizard.com/
 
Most of them use X-acto-style blades. The advantage is that they are fenced/guided cutters. You can go over the same line *exactly*, over and over, cutting a little deeper each time. You can also flip the sheet of ply over and make the same exact cut (same spacing from edge). You can't cut it in one pass, but I don't think I'd try to cut 1/8" balsa in one pass, either. A larger, more expensive version of a balsa stripper is a cutting gauge.
https://www.marples.co.uk/images/rosewood-gauge3-larger.jpg
The brass wedge is holding a blade that does the cutting. There are also marking/mortising gauges that use pins. Harbor Freight sell one for less than $10. You could get one of them, remove the pins, and add a holder for an X-acto blade.

Thanks buddy. Something else for me to consider.
 
Lastly, with all that's been said, and the time taken, and apparent costs involved for 'the right tool'/ Why not talk to a laser cutter / plans cutter to do them for you? Thinking of someone like laser lizard or even if Madcow would do you some laser cut pieces..

https://laserlizard.com/

I forgot about that. Worth looking into, especially if it's less expensive than a Maker studio membership. Thanks for the suggestion.
 
I use my scroll saw for cutting plywood fins and centering rings. Well worth the investment if you are going to do a lot of scratch building.
 
Yes, trying to make make long straight cuts with the grain for glider fuselages. And if you do decide to do a build thread re: these saws, techniques and how they can be used to cut what, please let me know so I can subscribe. I'm sure I'm not the only newbie out there that could really benefit from it.

I like to pretend I am handy in the shop, but I am pretty much a noob w.r.t. rocket building. I also suspect that I misuse most my my hand tools. ^_^

Ply turned out to be noticeably lighter than basswood and I've been unable to find spruce, ply, or any other hardwood sticks in hobby shops/crafting stores anywhere here (and there are only a handful anyway). As I'm just starting to get experience scratch building gliders, I'm beginning to see what works and what doesn't (e.g. a 1/8" balsa fuselage doesn't; it snapped in 2 places when the wings deployed). Two Apogee glider kits I built employ 1/8" ply and they're plenty strong, which is why I went with 1/8" ply (also they're available in sheet form at hobby shops here).

There're lots of ways to get where you want to go. Making up your own glue-lam from 1/32" balsa or basswood. Or laminating something tough between thin pieces of something rigid but brittle. A friend in our club brought an Estes Tercel to a low power launch. The fuselage stick is two pieces of balsa with a piece of Tyvek laminated between them. Seems to work pretty well.

Sticking to the problem at hand -- how to cut a 1/2" x 14" strip from 1/8' plywood; if you have a long-enough straight edge your razor saw will do the job. Scoring it on both faces with a utility knife before you saw might save you some sanding -- maybe -- but I don't think you need to invest in a $12-$30 back saw/pull saw for this job.

As for shopping it out to a laser cutter, if its just a rectangle, and its just one piece, seems like a lot of trouble and a lot of waiting and a lot of shipping for two cuts.
 
I like to pretend I am handy in the shop, but I am pretty much a noob w.r.t. rocket building. I also suspect that I misuse most my my hand tools. ^_^



There're lots of ways to get where you want to go. Making up your own glue-lam from 1/32" balsa or basswood. Or laminating something tough between thin pieces of something rigid but brittle. A friend in our club brought an Estes Tercel to a low power launch. The fuselage stick is two pieces of balsa with a piece of Tyvek laminated between them. Seems to work pretty well.

Sticking to the problem at hand -- how to cut a 1/2" x 14" strip from 1/8' plywood; if you have a long-enough straight edge your razor saw will do the job. Scoring it on both faces with a utility knife before you saw might save you some sanding -- maybe -- but I don't think you need to invest in a $12-$30 back saw/pull saw for this job.

As for shopping it out to a laser cutter, if its just a rectangle, and its just one piece, seems like a lot of trouble and a lot of waiting and a lot of shipping for two cuts.

The tyvek or a 'glass and balsa "sandwich" sounds promising and lighter than using basswood. It might also resist warping better, a persistent problem I've had even with ply strips. Maybe this bad weather worked in my favor since I haven't had the chance to check out any tools firsthand yet.
 
What's the most accurate and efficient way to cut 1/8" to 3/16" ply for a glider fuselage? I'd imagine using a utility or hobby knife would take forever and burn up a lot of blades, and I don't have any power saws (which would probably splinter/tear up thin ply like this). I'm new to this so any help/advice would be greatly appreciated.

Eric -

Did you ever come up with a good way to cut your plywood strips?
 
Personally, I woud cut that with a table saw, a zero clearance throat, and a may toothed blade.

For Japanese handsaws, for he newbie, call Japan Woodworker and let them know your application. The ones at Home Depot are not necessariy what you want. Too large of a tooth, or too much set, and you will have big tearout and not much fun. Using a handsaw takes some practice. The Japanese saws are excellent. For a long straight cut, I would scribe a line, cut it very slightly 'proud' of the line,(touching it on one side) and then sand back to the line for a nice clean edge.
 
Eric -

Did you ever come up with a good way to cut your plywood strips?

Since I have a large dremel with a rotary cutter wheel I gave that a try to see how it would work cutting off my uneven ragged edge. Not bad actually, since it cuts at high speed there was no splintering. But I don't have a guide so it wasn't a neat straight cut. I'll have to look into whether there's some kind of guide that I can attach to the dremel rather than relying on my eyes to guide it straight.

I also bought a pull saw but haven't had a chance to try it yet.
 
Personally, I woud cut that with a table saw, a zero clearance throat, and a may toothed blade.

For Japanese handsaws, for he newbie, call Japan Woodworker and let them know your application. The ones at Home Depot are not necessariy what you want. Too large of a tooth, or too much set, and you will have big tearout and not much fun. Using a handsaw takes some practice. The Japanese saws are excellent. For a long straight cut, I would scribe a line, cut it very slightly 'proud' of the line,(touching it on one side) and then sand back to the line for a nice clean edge.

In addition to a pull saw I also ordered a nice Stanley low angle block plane to even up the edge I butchered with the hacksaw. I'm hopeful that between the Dremel with a cutter wheel and some kind of guide or the pull saw, I'll be able to get some nice even strips for fuselages. If all else fails I'm considering throwing in the towel and using carbon fiber tubes.
 
One other thing to think about is something like a Pax #1 hand saw. It looks like an Xacto razor saw, but does not have a removable blade. I've got another hand saw, a bit smaller than the Pax, but doesn't have any maker's mark or ID.

c15ea3fcde66819307f1aece25fda052.jpg


or

https://www.zonatool.net/shop/razor-saws-miter-boxes/ultra-thin-kerf-razor-saw/
 
I have used Japanese handsaws for many years, and have gone through a bunch of blades. The 'pull' design is very efficient, and allows a thin kerk, among other things. With a sharp saw, it is possible to saw the end off a stick of hardwood that is very nearly paper thin. Accurate cuts are easy, after you learn.

I gave one to my Mother about 10 years ago, as a gift, at first she looked at me like I was crazy or something. This last visit she was telling me how she shows it to her friends and tells how well it cuts, when small projects need cutting.

The saw in my hand is the one I would choose for cutting thin ply as described in by the OP.

Each type of saw has a very specific purpose. If you try to use the wrong one for the given task, you will not necessariy have a good experience. :)

 
One other thing to think about is something like a Pax #1 hand saw. It looks like an Xacto razor saw, but does not have a removable blade. I've got another hand saw, a bit smaller than the Pax, but doesn't have any maker's mark or ID.

c15ea3fcde66819307f1aece25fda052.jpg


or

https://www.zonatool.net/shop/razor-saws-miter-boxes/ultra-thin-kerf-razor-saw/


I ended up buying a pull saw but haven't had a chance to try it yet. It doesn't have that support spine at the top like your model does because that support piece is what limited how long a strip I could cut when I tried a hacksaw and coping saw. I like how fine the teeth are on your Pax and it looks like it's at least 32 tpi or more. How shallow an angle can you use when cutting?
 
I have used Japanese handsaws for many years, and have gone through a bunch of blades. The 'pull' design is very efficient, and allows a thin kerk, among other things. With a sharp saw, it is possible to saw the end off a stick of hardwood that is very nearly paper thin. Accurate cuts are easy, after you learn.

I gave one to my Mother about 10 years ago, as a gift, at first she looked at me like I was crazy or something. This last visit she was telling me how she shows it to her friends and tells how well it cuts, when small projects need cutting.

The saw in my hand is the one I would choose for cutting thin ply as described in by the OP.

Each type of saw has a very specific purpose. If you try to use the wrong one for the given task, you will not necessariy have a good experience. :)


I ended up buying a pull saw that looks very much like the saws in the background, i.e. it doesn't have a support spine at the top to interfere with how long a strip of plywood I can cut. If I didn't have to angle the blade then it wouldn't be a problem, but once you do the support spine prevents you from cutting any further than the depth of the blade. The teeth on your saws are a bit finer than what I have on mine. I haven't had a chance to try mine out yet but hopefully [fingers crossed] it'll work. Impressive pull saw collection btw.
 
In addition to a pull saw I also ordered a nice Stanley low angle block plane to even up the edge I butchered with the hacksaw...

You are going to use a plane on the edge of a 1/2" tall piece of 1/8" plywood? How are you doing to secure it? A piece of sandpaper adhered to something flat is probably a better choice. The blade of the plane is going to be cutting across the grain for about half of the plies, and it would be much easier to hold the piece perpendicular to the sandpaper as you work the edge than it will be to keep the bed of the plane perpendicular to the piece -- provided you even have a way to keep such a small piece stationary against the drag of the blade.

Unless I am missing something, you are seriously overthinking this. You are still just trying to cut a 0.5" by 14" rectangle from a piece of 1/8" plywood?

Assuming your stock is longer than 14", you have a factory edge. Clamp down something for a straight edge and use your razor saw -- with the blade parallel to the work surface. Two cuts; one parallel to the factory edge and one to trim the piece to length.

If you are trying to get a 14" rectangle from a 12" x 12" piece or stock, for example, you'll need to make 4 cuts.

But honestly, why use 1/8 plywood? Cut multiple strips of something you can cut with a hobby knife and glue up your own lamination.
 
I ended up buying a pull saw but haven't had a chance to try it yet. It doesn't have that support spine at the top like your model does because that support piece is what limited how long a strip I could cut when I tried a hacksaw and coping saw. I like how fine the teeth are on your Pax and it looks like it's at least 32 tpi or more. How shallow an angle can you use when cutting?

If you score the cut line with a knife (always a good practice), you can put the blade down parallel to the wood. It's long enough that it's fairly easy to make a straight cut, but an edge guide always helps.
 
If you score the cut line with a knife (always a good practice), you can put the blade down parallel to the wood. It's long enough that it's fairly easy to make a straight cut, but an edge guide always helps.

Thanks, good to know. I'll also be sure to clamp down a scrap piece of wood or aluminum channel to help guide the saw blade, but I guess scoring and cutting slower and more carefully may be the key.
 
You are going to use a plane on the edge of a 1/2" tall piece of 1/8" plywood? How are you doing to secure it? A piece of sandpaper adhered to something flat is probably a better choice. The blade of the plane is going to be cutting across the grain for about half of the plies, and it would be much easier to hold the piece perpendicular to the sandpaper as you work the edge than it will be to keep the bed of the plane perpendicular to the piece -- provided you even have a way to keep such a small piece stationary against the drag of the blade.

Unless I am missing something, you are seriously overthinking this. You are still just trying to cut a 0.5" by 14" rectangle from a piece of 1/8" plywood?

Assuming your stock is longer than 14", you have a factory edge. Clamp down something for a straight edge and use your razor saw -- with the blade parallel to the work surface. Two cuts; one parallel to the factory edge and one to trim the piece to length.

If you are trying to get a 14" rectangle from a 12" x 12" piece or stock, for example, you'll need to make 4 cuts.

But honestly, why use 1/8 plywood? Cut multiple strips of something you can cut with a hobby knife and glue up your own lamination.

Guess I wasn't too clear; I sanded the fuselage piece I cut off to even it up. I was actually referring to the ragged edge I left on the larger original piece of plywood sheet. I want to even that up so that any more pieces I cut start out with at least one straight edge.
 
Thanks, good to know. I'll also be sure to clamp down a scrap piece of wood or aluminum channel to help guide the saw blade, but I guess scoring and cutting slower and more carefully may be the key.

A piece of aluminum angle several inches longer than the length of ply you're going to cut would make an excellent guide. You can make it better by 1) sanding/grinding/filing the sharp edge off of the outside of the angle. This gives the sawdust somewhere to collect without pushing the sawblade away. The other thing you could do instead, is to attach some sort of thin spacer under the angle that doesn't go all the way to the point - does the same thing. Modification 2) would be to glue some very strong magnets to the inside of the vertical side of the angle. This will help hold the saw tightly against (on the outside of the angle) it while you make the cut.
 
A piece of aluminum angle several inches longer than the length of ply you're going to cut would make an excellent guide. You can make it better by 1) sanding/grinding/filing the sharp edge off of the outside of the angle. This gives the sawdust somewhere to collect without pushing the sawblade away. The other thing you could do instead, is to attach some sort of thin spacer under the angle that doesn't go all the way to the point - does the same thing. Modification 2) would be to glue some very strong magnets to the inside of the vertical side of the angle. This will help hold the saw tightly against (on the outside of the angle) it while you make the cut.

Hey I like the idea about the magnets! Thanks for those pointers Dan.
 
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