✅ The SECRET To Cutting STRAIGHT - You Have to See This Magnetic Saw Guide For Woodworking
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- čas přidán 7. 09. 2024
- This clever magnetic 90 degree saw guide for woodworking makes it easy to cut straight every time. Please Subscribe if you like this video - thank you!
🔨 LINKS TO TOOLS AND PRODUCTS I USE IN THIS VIDEO*
🔸 Kataha Tatebiki Z Saw 10" Single Edge Rip Saw - amzn.to/39PbPHi
🔸 Neodymium 10mm x 2.6mm magnets (I used 3mm but 2.6mm will work just as well) - amzn.to/39LT7jZ
🔸 Brush On Liquid Super Glue - amzn.to/39OOpBP
🔸 2 Part Epoxy, 5 Minute Set - amzn.to/3QORin4
🔸 Machinist Ruler, 12in - Metric and Imperial - amzn.to/3NgZeKD
🔸 Forstner Bit, 10mm (25/64-Inch) Diameter, 8mm Shank - amzn.to/3yjklYI
🔸 DEWALT 20V MAX Cordless Drill / Driver Kit, Brushless, 1/2-Inch, 110V charger version - amzn.to/3OA37vg
🔸 Woodworking Chisel Set - amzn.to/3QHVrZH
🔸 IRWIN Woodworking Vise, 6-1/2-Inch - amzn.to/3NgazdV
🔸 DEWALT 10-Inch Table Saw, 32-1/2-Inch Rip Capacity, 110V model - amzn.to/3OCJHWF
* I might receive a small commission on any purchases made through the affiliate links above. Thank you for supporting my channel while it grows 🙂
You can read more about this saw guide at the following blog post on my website: www.kiwiworksh...
This saw guide works for both 90 degree rip cuts and cross cuts.
Materials required:
- Hardwood of medium to high density. I used heart Rimu but Walnut is another good option.
- Neodymium magnets (rare earth) 10mm x 3mm [3/8" x 1/8"]
- Super glue
- 5 minute epoxy
- Wood finish (I used my chopping/cutting board conditioner which is made from mineral oil and beeswax)
Tools required:
- Saw (hand saw or table saw)
- Chisel
- Electric drill
- 10mm [3/8"] forstner drill bit
- Mallet
--------- Tags ---------
#woodworking #magnetic #cutting
--------- Music ---------
"Acoustic guitar arrangement for song" by Trev Row
/ megatrev
Just reading some of the comments. Why the negativity out there?! Nice jig, nice build and nice video. I agree with Steve, anything to keep my hand steady at my age is a real bonus AND satisfying to cut a damn straight line as well. Will definitely by building this one.
Thanks Kevan, nice to read your comment and good to hear you have a use for this jig. Provided the saw teeth are properly set and the jig is perfectly square, it works very well. Good luck with your build.
@@kiwiworkshop Have fallen in love with Japanese pull saws, virtually no kerf to worry about. Nice clean cuts.
@@kevanstreeter2431 I am with you here, they are a pleasure to use
"Why the negativity out there?!"
Crab mentality. If they can't get out of the bucket, nobody can. There's a reason they're here futzing around CZcams instead of making content.
very handy thing to have, unfortunately I do not have a table saw of such quality, so unable to make for myself:-( do you make and sell ??
As for the back cut saw, wow they are something else, I should really get one at least, I have a Silky big boy for harvesting wood for carvings spoons and such like, and it's absolutely 💯 % fantastic saw to use and such a beautiful clean cut.
cheers Les.
I was a lifelong carpenter for a living and this is one smart idea!!! Good for you dude and it is ALWAYS nice when true pros share!!
I always thought I was the only one who couldn't saw straight. Now I can see I have many friends! Many thanks, I've got some fine redwood which will soon be magnetised!
I’m starting woodworking late in life. The cost of materials means my errors are costly too! I’ll be making this jig which will help keep my re-work rate down. Thanks for posting this helpful idea.
I'm pleased to hear this jig design will be helpful for you. Good luck and and thanks for your comment!
I just ride around with a sawzall and anytime I see some good wood laying out that straight I pick it up so I can practice with it no cost at all!! I don't go for any of my high-quality expensive wood until I've mastered what I want to do works great
Fabulous! Much quicker and easier than using the reflections of the wood to keep it aligned.
Very true, thanks
I'm convinced my childhood in a dojo has helped me master the pull saw. Everything Sensei taught us applies. Meditation, patience, kata, repetition, foot, arm position, and centering. Building this to get even better. Love it
Hallo, danke das du diese Idee mit uns allen teilst.
Das werde ich als nächstes nach bauen, um alle Projekte die danach kommen von Anfang an besser zu machen.
Damit hast du dich ein bisschen unstrerblich gemacht. Dein Verstand wird in meine Werkstatt einziehen.
Dankeschön
Regarding the nattering nabobs of negativity who tout skill over tools, a person with essential tremors or someone with vision challenges would absolutely need this guide. It would restore the pleasure of woodworking for them. Please note that in the movie Bambi it was said, (paraphrased to eliminate a double negative) "If you can't say something nice, don't say anything at all."
Thank you for putting this out there. Please make version two with the holding lips. I want to see it...
No problem. I'm giving it some thought re the "holding lips". It would work well for the narrow-ish board I cross cut in my video. But for a wider board, you would be forced to hold the saw guide on one side, which might allow an inaccuracy across the whole cut. That might not be an issue, I will experiment at some stage. Currently I'm working on a sloped version of this guide for dovetails which will be in an upcoming video (but maybe not the next one). Thanks for your comment, glad you can see how this guide will work well for people of varying abilities.
Thanks for repping folks with disabilities and/or general age related failing abilities .. lots of people out here who are just a couple tremors away from being able to maintain a hobby that keeps them happy and healthy.
I have to say, this is a great start! I’ve been woodworking for a good few years and far out, to cut straight seems an impossibility! I weakened and bought a drop saw but for small & softwood cuts, my Japanese saws should be the way. I’ll build one for sure, Thankyou mate!
Wow , that a really incredible idea . most videos like this are rubbish but this is genius
Nice jig! Great idea. To offer a little “video” production advice: when laying in text on a video, during editing it’s best to play back the video while reading your text to yourself out loud at a normal pace. This will allow you to figure out the proper length of time that this text needs to appear on screen to allow people to read it before the text disappears. I watched this video and had to stop and back up the video several times in order to read all the text. I’m sure others had to do that as well. Also, reading text when watching a video does pull a viewer’s attention away from actually seeing what’s happening on the video, so laying down a voiceover is always best. Keep up the good work; great jig!
Appreciate your comment. Adding the text on this one was an afterthought, the initial intention of the video for interest only. One thing you can do is change the playback speed of the video using the CZcams video player controls to slow it right down. Moving forwards, I'm considering running two channels. One will be for entertainment purposes only, i.e. people who are not interested in the technical details can just watch me make something and listen to the tool noises etc. The other channel will have more of a technical/DIY focus and I will voice over the videos to explain what's happening. Thanks
put a small vertical (going up) on the top of your t. then when you flip it over for the second cut you have a Lip to hold against the edge of the workpiece so you don’t have to push down so hard.
That's actually a great suggestion, if I make a V2 I will add that addition. Thanks!
I thought the same! 😀
Like a mini bench-hook.
Sorry. A small vertical? Can you elaborate please
Anything that helps produce better craftsmanship is a good tool - bravo
Thanks, appreciate your comment
That's a nice little helper! Sometimes a saw wifh a ridgid back might be a good choice too, but this helped is definitely a great thing to have!
Clever. Genuinely useful, and relatively simple to make. Nice video.
With my pull saw skills, I'm 99% sure I could use this jig and still manage to cut a crooked line somehow.
*cries in the corner
Haha, I'm sure you are better than you give yourself credit for 🙂
@@kiwiworkshop I've been working my way through an entire 2x4, sawing off about 3/4" slices at a time. After a box full of slices I managed to get a few consecutive straight cuts.
So there is some progress! Slow progress, but progress nonetheless I suppose.
You need to start the cut at a sharp angle down then across the top line. Turn the piece around and do the same thing. You also need a ryoba with a long handle and do the cut with both hands as if you’re a samurai warrior. No need for a jig. This is what I learned after watching many Japanese woodworking videos
This gimme idea to make my own guitar fretboard slot sawing..thanks!
I'll try 3d-printing a version of this :) I'm going to insert the magnets 'from the back' in deep holes instead though, so the magnets can be hidden just beneath the surface. Maybe that's possible with some very careful drilling in wood too?
Great idea, now to apply that same theory to angle cuts for kumiko joinery would be great as well.
I'm pretty certain I will build this once my holiday starts.
My two cents though: usually you don't make the surface more straight with sanding, you make it less. I'm planning on running the piece on a jointer-planer on all sides before cutting, should make it straight, and using very little epoxy.
Nice video and jig, thanks. I am one of those transitioning away from power tools (large tools to start with, table saw, sliding miter saw, large band saw, ...). I have used crude (non magnetic) guides with some success. I have also taken some advice from Paul sellers (draw the cut line on top, front, and back, make a few passes then flip the board, make more passes, flip, and so on). Now I'm thinking that for cuts that need to be right (i.e. can't easily be fixed), use a guide with all 3 cut lines drawn and flip back and forth. Perhaps this is overkill though.
Glad you like the jig and video. This jig is great for quick and accurate cuts in the world of hand tools. If anyone needs advice on the proper user of hand tools, Paul Sellers is certainly the man. Thanks for your comment.
From one woodworking kiwi to the next... Very nice my man.
Thanks, most appreciated!
Nice. I plan to build something like this. Thanks for sharing.
Well made, informative, and usefull. Thanks for sharing.
Thanks, really appreciate your feedback.
@@kiwiworkshop Me too! Sub’d $ Belld thanks
Congratulations! Very interesting! Tks for sharing. I from Brazil.
No problem, thanks for watching!
Boa 💡 ideia...parabéns!
Yes sir,, thnks
This is a homemade katz- moses jig and work fairly well. The production version does dovetails also
Although there are similarities with the Katz-Moses jig, this one is designed primarily for cutting straight. It has a longer cutting guide, additional magnets, supports the saw blade down the entire stem, works for cross cuts as well as rip cuts and has sandpaper grip included for each type of cut. The concept of saw guides have actually been around for decades, probably even centuries and have appeared in a number of woodworking books. Different elements of all the saw guides I've seen went into this one. If someone intends on getting into dovetails, then yes, a Dovetail specific jig would be a good option. For someone who simply wants to cut straight (both rip cuts and cross cuts), the saw guide presented in this video would be a good option. The design is also uncomplicated compared to a dovetail guide and is much easier to make.
This is awesome. I am trying to avoid buying a table saw but would appreciate the help with cutting straight. I do have access to a 3d printer so I might just make an initial jig with that even though I prefer the wooden version you have. Maybe print the first one and use that to make a more durable (and attractive) wooden one. Thank you for the video and great idea.
If you have a hand plane it is easy to make a shooting board from there and then a saw jig.
Clever tool making my friend . A very nice job. Well done. Cheers from Michael. Australia.
Thanks, really appreciate your comment. Cheers from NZ
@KiwiWorkshop I just think you should get some recognition for how patient and gracious you are in the comments ..
It's my pleasure, thank you Will
"Hur durr thas not reeeeel woodwerkin reeeee!"
Cool idea, thanks. I default to my table saw for almost everything, and I appreciate this as a way to get into hand tools beside flush cutoffs.
No problem, glad you like it. Transitioning from power tools to hand tools is a good use case I see for this saw guide. In the woodworking forums, I often hear of power tool guys giving hand tools a shot, getting frustrated then going back to the power tools they are used to. And having a table saw available certainly helps with accurate cuts for this build.
Oh man!! Had to add this one to my projects list! It is becoming endless 😬. Good job mate!
Haha, sorry! I also have one of those lists and don't think I will ever get on top of it... Thanks.
Bonjour, Idée ingénieuse à adopter ! Félicitations et remerciements pour ce partage ! De cordiales civilités de France. Je me suis abonné à votre chaîne..... Patrick
Merci! Bonjour de New Zealand ! Daniel
Nice idea. Thanks for sharing.
I used to think these things were a cheeky short cut type of thing, but I started off using a magnetic cutting guide for dovetails. After a while I ditched the guide and started freehand cutting again. i think the guide did help me build up some muscle memory for cutting. So if it helps.......why not?
Very good! Thanks for posting that, appreciated.
My pleasure!
Brilliant idea. Thanks for sharing it.
My pleasure, thanks
If you keep your saw clean you can use the reflection of the workpiece on the saw blade, line the reflection up with the work piece to get perfect square cuts everytime
Yeah, that's another way of doing it. Thanks.
Clever. I think I'm going to modify this for cutting dovetails.
I haven't watched the video yet, but I already see how this can be improved with three ball bearings for the saw to roll on.
Or just use a traditional frame saw - the size of the frame makes it easier to fix the angle of the saw to some point and keep it close to that angle.
Hi Daniel, please don't take this the wrong way because it is *not* a criticism or a negative comment.
If I can't cut a straight line (and I can't I am just hopeless) then this jig would be just ideal for me but to make it I need to not only cut several straight lines but they also need to be square. Now if only I had a jig for that. Do you see the small problem I have? Nice idea though. 👍👍
Now thats an idea very nice, i bet everyone who posts negative comments on this video doesnt say the same on videos with drill presses
Smart tool, thank you !
I have the same issue while sawing … 😬
I think will make one !
Any link for the saw with European shipping plz ?
What a great idea and another awesome useful use for magnets
For sure, so many awesome things you can do with magnets. Thanks.
Very good jig production.Will have a go at making one soon, in the meantime I wonder if theres a magnetic tri Square available?
The simplest way is to use the reflection of the wood in the saw. It shouldn't need explaining.
> 275.000 Views and getting more each day. Keep on Daniel, you are doing a great job. Best wishes for your channel from Catalonia.
Thank you again Josep. Yes, my latest videos have had many more views than I expected, so must be doing something right! Currently working on the next video and shouldn't be too far away. I have fond memories of Catalonia when I visited about 10 years ago. Best wishes from New Zealand.
I have so much to do...it's overwhelming.
Thanks for posting.
No problem, finding the time is the tricky part right?
I'm 46 now but started cabinetmaking when I was 14, in year 9. By about half way through year 9 I could cut square along both axes with a tenon saw, freehand.
These devices are nice but it's much better to develop the skills, that took teenage me all of 6 months to develop 40 something years ago, just had to put my mind to it as I was NOT a natural at it.
I also encourage developing the skills to cut freehand if someone has the time and patience. A saw guide can help for complete beginners, the occasional woodworker or someone transitioning from power tools into hand tools. I see them a bit like trainer wheels on a bike, use the saw guide to get some confidence then try without it. Provided you are using proper technique (body and head position etc), I don't see the harm in them. For myself, I'm getting into hand cut dovetails for the first time and made some saw guides to use for my first few projects. I also made some sloped dovetail guides which I will put in another video. Thanks for your comment.
I am 71, as I get older I notice that the skills I once took for granted are starting to diminish. I need this jig for cutting the scales (handles) for the knives I still make.
The older I get, the better I was.
@@kiwiworkshop yeah agreed, no harm in using a guide and yours is a very nicely executed one
@@zacktoby good to hear that you have a use for this jig and thanks for sharing what you will use it for.
@@OneManBandWoodworks thanks
Cool jig, ill be making this!
Great idea. Good job 👍💫👍
Thank you very much
You can polish the saw blade, then look while cutting at the blade. If its mirroring in one line its 90° cut.
Wasted effort to mirror polish a disposable saw blade. There is unusual hardening and precision profile so they're not made to be resharpened.
This is exactly what I'm looking for, 👍 nice
High, I know this was a year ago but, can you please tell me what size magnets you used? and also drill bit?
Was it a normal wood bit or a very small forstner bit ?
I am also guessing the magnets are very slightly resest into the wood.
I will thank you in anticipation for a reply if you see this.
Cheers Les.
Inspiration for me.
Neat. Jonathan Katz-Moses sells acrylic versions set for common dovetails.
Yep, if someone needs a dovetail saw guide, the Katz-Moses one looks like a good option. Thanks.
Good idea 👍👍
Thanks, glad you like it. Hopefully the design and video are easy enough to follow if people want to make their own.
What a clever idea , love it
Glad you like it!
You are a genius bro!
Haha, thanks. I can't claim to have invented a magnetic saw guide. But have (I think) come up with a really good design for anyone who simply wants to cut straight (rip cuts and cross cuts).
Just a thought, I think if I were to make one, one side would be at an angle for cutting Tails for Dovetails. Just a random idea. Cheers
don't really like gizmos, but this one is smart! well done....
Thanks, glad you like it. It does indeed work very well.
What a great idea! Definitely going to make myself one of those! Thanks for sharing.
No problem! Glad you like it, thanks.
The irony here is that in order to make this, I'd have to cut straight! An excellent idea by the way.
Haha, well there's more than one way to make one. If you have access to a 3D printer, you could print one! Thanks.
Cool guitar
i like it thnx
The negative comments... yawn... I didn't see anything constructive, or useful. Just immaturity and pettiness. What's the message? You're so advanced? (I'm thinking you're out of work, bitter, and have nothing better to do than troll on CZcams. lol) I've made countless straight cuts in my life, and I don't remember ever getting recognition, or a six foot trophy for any of them. And, in five decades, the subject of cutting straight by hand was never a topic (for bragging) when I interacted with fellow woodworkers.
I've been doing woodwork for nearly 50 years. This is a worthwhile post by Kiwi Workshop. Due to nerve damage, and aging vision, I don't always have the dexterity, control and vision. Sometimes, you're working with expensive materials, or a piece (think inlay) that you've already invested considerable time, and you don't want to risk messing it up.
Really nice to get such a constructive comment here from a fellow woodworker with the amount of experience you have. Thank you so much, it's most appreciated!
It's also been very encouraging to read in the comments how my jig design will be used by others and help them out for varying reasons.
Well done.
Beatutiful.👍👍👍
Glad you like it, thanks!
do you need to have the magnets on both sides ?
No, but sometimes it can be useful not having to turn the jig around to cut on the other side
Very clever, thanks.
You're welcome!
Definitely figure out a price n go for it!! U'll definitely get the lazy folks to buy.🤔😃
Excellent idea boss👍😉
Thanks! For now I'm just happy to share the design for this saw guide 🙂
This is a great diy thing but already exists almost exactly as this product unfortunately. Jonathan Katz Moses is the person who originally made it, including dovetail angles as well, so definitely don’t go around selling it. Kudos though, it is a great idea!
@@JPBerkleeDude Ooops. Oh well.
@@JPBerkleeDude thanks for the Kudos. The concept of a saw guide has been around for decades, probably even centuries. Adding magnets to them is reasonably new and David Barron was the first person I head of who did it. There were likely others before him. Regarding the design of my guide, it's actually quite different from the Katz Moses one. His one, as you say, is primarily made for dovetail angles. My guide is designed for cutting straight at 90 degree angles. The Katz Moses guide does have a 90 degree side but does not support the saw down the entire stem like my design. If I wanted to be picky, I could also point out that it does not have sandpaper to hold it in place like mine and would not work very well for a cross cut (last example in my video). And since my guide is designed to handle longer cuts than just dovetail widths, it has a longer body and additional magnet (3 per side, not 2). I'm not planning on selling it but if i did, I can't see there being any issues. I haven't seen any 90 degree magnetic saw guides with exactly the same design as my one.
As you mentioned in your first sentence, this is a great DIY project and that was the main reason I made the video. I wanted to share the design and how I made it. Pleasing to see in the comments there are people who will find this useful and are planning on making one! Thanks again.
@@richardc6269 don't worry, I did not copy any other design (see my other reply in this thread). There will always be similarities between saw guide designs, there are only so many ways you can make them. Thanks again for your comment.
I often apply paste furniture wax directly to wood when I'm making small, functional items, so I perked up when I saw the Kiwi Board Conditioner. Alas, it must be out of production as I cannot find it anywhere online. Has it been replaced by a different product?
I produced a small run of the Kiwi Workshop board conditioner when I was making chopping boards. Don't have any available at the moment sorry. It's simply a mixture of food grade mineral oil and beeswax.
@@kiwiworkshop Thanks; sounds perfect.
C'est pas mal... mais il vous faudra quand même un jour apprendre à couper droit sans dispositif. :p
I’m a gonna make one
I don't have a power tool. I wonder if 3d Printing would achieve a similar result O:
Yes, I'm sure you could 3D print one of these. The firmer the material, the better. A wayward saw tooth will bite in to soft material. I used a firm/dense wood.
It's not like these japanese saws have no set. How is it that you're not chewing up the face of your guide on those first two cuts?
I'm using it with a ZetSaw RIP FINE H-250. All teeth are properly set and so far, it hasn't cut into the saw guide.
Th mate❤😊
I can’t cut a straight line, I certainly can’t make this. Perhaps I can buy one.
Wow! PFM!
I have a table saw but I use radial arm saw for these yet the ONLY reason I clicked on this was because I thought you had a tip for cutting these with a hand saw.
It could be cut with a handsaw and chisel but it would be a bit tricky to get perfectly square results (experienced hand tool woodworkers could do it no sweat). My hand tool skills are not at that level yet, so I used my table saw. Sorry the video wasn't what you thought it would be, I tried to make it obvious in the thumbnail image.
Simple. Apply a much stable control on desired postion you are moving that excel more than the resistance. Your hand and wrist along with forearm have insufficient strength to apply force and maintain control on a clean vertical cut. Which is the reason why you design mechanism that aids by filling in that gap of insufficiency. The tool that you made is very impressive. Give thanks to God for your craftsmanship. 👍
Thank you
Ooo pretty
Hmnnn...I might try an angled version to cut dovetails.
I'm actually working on an angled dovetail version of this saw guide right now. I made two, one with a 1:8 slope and another one with a 1:6 slope. I will be finished tomorrow and I will put it in an upcoming video. But maybe not the next one so I don't release two magnetic saw guide videos in a row. i.e. give my subscribers something a bit different next.
Real craftmanship leads to straight cuts . . . . look at history
Look at the video comments on why this saw guide is useful to many people. There is nothing wrong with someone who is unable to hold a saw straight due to a medical condition (tremors, poor eyesight etc) using a saw guide like this for assisting with straight cuts. It's still real craftmanship.
@@kiwiworkshop thanks for the clarification
No problem, thanks
nice jig
Thanks, glad you like it
What is drill but and glue that you used?
It's a 10mm forstner drill bit and the glue is Titebond type III
Talk about getting the polarity correct?.. I love the problem solving innovation. Paint it red and sell it for $300 ;-).
Both the north and south poles of the magnets are equal in holding power. And they were spaced far enough apart on each side that there was no interaction of the poles. In summary, it didn't matter, but perhaps I should have mentioned something about it in the captions. Glad you liked the video and yeah, red ones are always sell for more! Thanks for your comment.
Using a nail/screw like he did here to hold them should address the possibility of laying them in wrong.
👏👏👏
Definitely a reasonable idea for anyone that's not interested in obtaining skill - although I doubt they could make this jig accurately if they have no skills (maybe a carpenter friend can make it for them). I'm with the others that have stated that it's better to take your time and learn from your mistakes, ultimately gaining the skills to cut straight through practice.
I get it though... CZcams content and all that...
It wasn't my intention at all that this should be a replacement for obtaining skill. I just wanted to show that it's possible and could actually help people transition into hand tool woodworking. Magnetic saw guides can be purchased, however the designs are different from mine.
@@kiwiworkshop It's all good ;) I just agree that practice is better
More of a tool than a secret
A secret tool perhaps? Well, a secret tool until this video was released...
Do you sell them? If so how much will I cost
Not for sale sorry but thanks for asking.
In the first example, it does not appear that tha work piece was marked ahead to show where the cut should be nmade. Using the magnetic guide is one way of training your muscles to make proper cuts, but unless you want to have a cabinet full of guides for different angles, not to mention compound angles, you would be better served by actually lesrning how to use a saw.
The magnetic guide does not really work well with longer cuts. The video shows only abou 2 inch of cut. The longer the cut the worst the error. This is a geometric principle that a 0.5⁰ small error will result in alignment error the longer down the plank one cuts.
Kralll
Or use a miter saw.
👌👍🤝😎
Do you sale them?
Sorry, not for sale
@@kiwiworkshop I'll buy 2 if you decide to start a business selling them.
Why not just use the Bench Saw to cut straight? you used it originally to make the saw guide, to make sure the guide was square & straight! 🤔
One target audience for this video is power tool users moving to hand tools. We have Paul Sellers to thank for this, since he made hand tools cool again! Also, the fine cuts made with a Japanese pull saw are not possible from my table saw. The rip cut (first cut demonstrated) is also not possible from a table saw. Regarding how the saw guide is made, there are other methods such as 3D printing.
Having used these saws near all my life, I can cut pretty damn straight. No crutches. Not bad though to start out possibly. But practice makes perfect and one should and can cut straight without anything but eye sight. Longer pieces you can use a pencil line. I did find out that each saw has it's own quirks so be on the lookout for that.
Yes, with practice, you can develop the skills and muscle memory to saw pretty straight. There are a number of reasons why someone might choose to use a straight cutting guide like this (poor eyesight, medical condition making it difficult to hold the saw steady, beginners just to get some confidence and the feel for it, power tool user transitioning into hand tools, the occasional woodworker who would simply like perfect results on every cut). Thanks.