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Jim Paulson
01-09-2009, 10:11 AM
Hi Guys,

I confess I'm less of a machinist than some of you so maybe you'll not mind if I ask this: what would be a good approach to get new teeth cut on an old saw? I have an old backsaw that is crosscut and I'd like to change it to a rip. I am also less concerned with some of the nuances of blade thickness although I love the performance of my LN dovetail saw.
Should I send to someone who does that or should I try to file new teeth? Who does that? I'd be a complete novice on filing new teeth, but filing a 10 tpi rip seems a bit of a challenge. I'd be happier trying to file teeth on a panel saw, but I haven't done that yet either.

Jim

Robert Rozaieski
01-09-2009, 11:25 AM
Jim,

If all you want to do is change from crosscut to rip, you don't need to have new teeth cut in. In fact, your 10 point saw would be the perfect saw to learn this on. The teeth are not too small and not so big that you will have to file a lot of metal off. I suggest trying it yourself. The worst that will happen is that you screw it up and THEN have to send it out. But really, try it out yourself before immediately sending it to someone else. Rip teeth are a piece of cake to file. And if you aren't changing the number of teeth or the rake angle it's even easier. Here's a brief description of how I would do this.

First, get yourself a saw file. For a 10 point saw you can use a 6" extra-slim, a 6" double-extra slim or a 5" extra slim all successfully. These are available for a couple of bucks from a lot of places. Home Depot even carries the 6" extra-slim I believe. You will also want a mil-file for jointing. Anything from a 6" to a 12" flat mill file will work. Forget a saw set for now. The saw you have likely has too much set as it is so filing the teeth will likely remove just the right mount to make the set right.

Next, get three scraps of wood. Two should be flat and at least as long as your saw plate. These will be your make-do saw vise. The third piece of wood should be square on two adjacent sides. This will be used with your mil file to make sure you joint your saw teeth square.

Now, take a bevel gauge and gauge your saw's rake angle. This is the angle that the front of the saw tooth makes with the bottom of the saw plate. Just get close. It doesn't need to be perfect. This is the angle you want to file at. Don't worry about what the exact angle is now, just use whatever angle you gauge from the the saw with your bevel to make a rake angle alignment block for your file following Pete Taran's directions here (half way down the page look for "Making a Rake Alignment Jig):
http://www.vintagesaws.com/library/primer/sharp.html
If you really want to change the rake angle, feel free to do so but you may need to joint the teeth a little lower and file a little more to do so. No big deal but not neccessary for your first go round.

Now you are ready to get started. First you need to joint the teeth so they are all the same height. place one stick of your make-do saw vise on either side of the saw plate and clamp the whole thing in your bench vise with as much of the blade above the bench top as you can get. Now hold the mil file on top of the third piece of wood and using the wood as a fence to hold the file flat, file the tips of the teeth from the heel of the saw to the toe. Just make enough smooth strokes to get a small flat spot on the top of each tooth. This will make all the teeth the same height. It should only take two or three strokes with the mil file if your teeth are not that bad to begin with.

Now, reset your make-do saw vise so only a very little of the blade sticks up above the vise. You want the teeth to be as close to the vise as they can be and still have access to file them. This will reduce vibration as you file across the the saw plate. Place your file in the rake alignment block as instructed in Pete's directions. Make sure the arrow points at the handle so you get the rake angle right.

You now want to file the front side of all the teeth that are leaning away from you. Start at the toe and work towards the handle filing every other tooth straight across (i.e. zero fleam). Don't worry about getting this perfect. A little bit of fleam from hand filing makes the saw cut smoother so it's perfectly ok. When you file, concentrate on putting the file into the corner of the gullet and keeping your rake alignment jig level. Go slow and file only the fronts of the teeth that are set away from you until the flat spot from jointing almost dissappears...ALMOST but not completely.

Now turn the saw around in the vise to prepare for filing the teeth you skipped. Remember to flip your rake alignment gauge as well so the handle arrow is pointing in the other direction. Now file the fronts of the teeth that you skipped before, which will be the ones that are set away from you (they were set toward you before you turned the saw around ;)). File just until the flats on the tips disappear and no further. This will also take care of the tiny bit of flat left on the teeth you filed the first pass since you are filing the back of those teeth now.

Finally, take the saw out of the vise and make one very light pass with a fine honing stone on each side of the saw plate from heel to toe to remove the filing burrs.

Now make a cut with your saw and be proud that you did it yourself :D. It is actually harder to write about it than it is to do it. And it's not a big deal if you screw it up a little. If it cuts ok you're good. If it needs more work, you can simply rejoint the teeth and try again. If the saw needs more set, you can get an inexpensive saw set and add just a little but it likely won't need it right away.

Try it, really! It's really very easy to do. Make it your new skill learned for 2009 ;)!

Jim Koepke
01-09-2009, 11:44 AM
Robert is right.

My first saw was done without any instructions. It was a tree saw. The improvement was so good, that I figured I should learn how to really sharpen a saw.

I am now getting to the point after just a few sharpenings that my next saw project is likely to be making new teeth on a saw that has none.

Read the instructions that Robert linked and you will be well armed for the task.

Good sawing,

jim

Jim Paulson
01-09-2009, 2:23 PM
Thanks Robert and Jim for your encouragement. I should have given more information I guess especially with the thoroughness that Robert produced in his comment. I gather you both might suggest now that if want a rip saw it might be advantageous to make it a 12 or 13 point rip for now. I have two candidate saws that are Disstons, one 12" with 12 tpi and another at 14 inches with 13 tpi. That might be what I do and I'll certainly follow your advice. Eventually, I am hoping to have a 10 point rip to use as a tenon saw. LN and others have nice ones, but the practical side needs to be there for me these days.

Jim

Alan DuBoff
01-09-2009, 2:42 PM
10 ppi is pretty course for a tenon saw. I would suggest 12 ppi, but all of our mileage varies.

I use a Foley to stamp teeth, but the method Robert links to and describes above works fine.

Your 12" with 12ppi sounds like a good saw to use for that. My $0.02.

Robert Rozaieski
01-09-2009, 3:01 PM
Jim,

Keeping the TPI you have now is the best way to learn to sharpen. However, once you've done it once or twice, cutting in completely new teeth is not hard to do with a file. I will say that you will likely grow tired of the slow cutting of a 14 PPI (13 TPI) tenon saw after some use. My current tenon saw is 14 PPI (13 TPI) and I don't like the slow cutting. It's fine in narrow tenons but clogs badly in wider tenons. I'm currently making a new tenon saw that will be pitched at about 11-12 PPI (10-11 TPI).

To cut in new teeth you would first obviously need to file off all the existing teeth using the mil file. Then you need to mark the spacing for the new teeth and file them in. There are two ways I have used to do this.

With the first method, you print out a template. You can use a CAD program or other drawing program to draw a bunch of lines all spaced for your particular tooth spacing. For a 10 PPI (9 TPI) saw you want the spacing to be...wait for it...1/10th of an inch. For an 11 PPI (10 TPI) saw, the spacing is 1/11th of an inch. Pretty simple right. :D Next you use this template, clamped into your saw vise with your saw, to guide your file. Just place the corner of the file on the line and file in a new tooth. Just go a little bit until you have all the teeth marked but not completely shaped. Then go back and file away the flats like you would sharpen. You may need to make several passes just taking a few swipes on each tooth each pass and gradually sneak up on the final tooth shape to avoid filing too deep and changing the tooth spacing.

The beauty of this though is that you can cut all the teeth from one side of the saw without having to turn it around since there is no set yet. Once you have the teeth cut, following the sharpening instructions, starting with the jointing, but this time, after you joint the teeth, set them before you file them. Pretty simple. ;)

The other way to mark the position of the new teeth is to clamp a hacksaw blade with the same PPI that you want for your saw along side your blank saw plate and use it as a template to establish the spacing. I like the lines better myself as I feel like the slightly irregular spacing that comes from freehand (kind of) filing the teeth into the saw plate make it chatter less in use, however, this may just be me.

Good luck with your filing. Be sure to post your results.

Bill Hays
01-09-2009, 3:39 PM
Filing saw teeth is no doubt fun, but not as much fun as working with wood for me. I send my saws out on the rare occasion they need sharpening. The precision of mechanical filing seems to pay off in the accuracy of the cut.

If you are going to file though, think about getting a saw vise and set. They are common at tool auctions and cost very little; not much in demand I guess. Any general sharpening shop ought to sharpen saws, at least the common tooth sizes. The last time I had it done it was just a few dollars per saw.

Bill

Matt Edwards
01-09-2009, 9:40 PM
Its true that saw sharpening isn't for everyone. It requires lots of patience in developing the the skill to do it effectively. IMO its a skill worth learning. Granted, I have no desire to sit in my shop joint and sharpen panel saws by hand all day. But, there are times that I enjoy the break from working with tools and enjoy working on them.

There is a pretty fair amount of satisfaction when the patience and practice yields a saw that performs better than any other in the till. I would recommend starting simple as Robert suggested, no need to run out and break the bank. Changing from cross cut to rip is pretty minor, and will go a long way in the practice it will give you. Actually, if you can joint and sharpen a saw, you can cut new teeth. Cutting teeth by hand is more layout, touch and repetition than super skill.

I'm not at all an expert, but I do maintain my saws, and I have made several of my joinery saws and re toothed the other joinery saws that I referbed.

Regards!
Matt

Jim Paulson
01-10-2009, 8:44 AM
Hi,

I am still thinking about Robert's comments on sharpening. I love his idea of using a hacksaw blade as a guide to cutting new teeth. That would be more my style. Who knows maybe 2009 is the year to learn about refurbishing saw blades. I have a saw vise and set thanks to a relative, but I confess that I haven't put them much to use. This forum is great for motivating another person to try something.

I am also thinking that this gives me the excuse to pick up a couple old saws for learning sake.

God bless all of you,
Jim

Jim Paulson
01-10-2009, 8:51 AM
Hello again,

Last night was our mall trip and the reason I was delayed in responding.
Hope you have warmer temps than us here. Our outside temp this morning is 1 degree Farenheit.

Jim

Alan DuBoff
01-10-2009, 12:39 PM
I have a saw vise and set thanks to a relative, but I confess that I haven't put them much to use. This forum is great for motivating another person to try something.
Your half way there, get a file and your ready to give it a whirl. If you have any questions, ask.

John Schreiber
01-10-2009, 7:24 PM
. . . I love his idea of using a hacksaw blade as a guide to cutting new teeth. . . .
Has anyone tried to use threaded rod as a guide? It was just an idea I had.

Jim Koepke
01-11-2009, 12:58 AM
Has anyone tried to use threaded rod as a guide? It was just an idea I had.

I think any thing with a regular spacing has likely been used at one time or another.

Alan posted a link to a site that has patterns you can print for spacing, but for some reason it is now telling me I am not authorized to access the page. May be late night site administration.

If it continues to keep me out, I will have to make my own with computer and printer.

jim

Alan DuBoff
01-11-2009, 3:32 AM
Alan posted a link to a site that has patterns you can print for spacing, but for some reason it is now telling me I am not authorized to access the page. May be late night site administration.
I sent Leif an email, he must have changed something and blammo! It happens...:-) I'm not sure what the direct links were to the ppi charts, they're PDFs I think.

I'll look and see if I can find them on my computer.

Daren K Nelson
01-11-2009, 8:30 AM
I have posted this link here before. Like Allen I have one of the Foley retoothers, this is a video of it running. It normally sets on the bench, but to film it by myself I had to put it on the floor and mount the camera to the bench (clamped the camera in my saw filing vise of all things :rolleyes:) http://www.youtube.com/watch?v=lkeLXXwxRek

Jim Paulson
01-11-2009, 9:38 AM
Heh Daren,

That was really cool. Got to run to church now. Maybe some day I can find one of those.

Thanks,
Jim Paulson

Alan DuBoff
01-11-2009, 1:51 PM
Alan posted a link to a site that has patterns you can print for spacing, but for some reason it is now telling me I am not authorized to access the page. May be late night site administration.
I got a reply from Leif, he's gonna look at it today. He thinks the database got munged up somehow.

Jim Koepke
01-12-2009, 3:39 AM
It looks like it is back up at the original link you posted:

http://www.norsewoodsmith.com/node/76

This morning it had a site maintenance page, so I guess it got fixed.

Now I should take the time to download the files while the gettin' is good.

jim

Jim Paulson
01-12-2009, 8:14 AM
Heh Jim,

Thanks. I did the downloads and I found a saw to test this out on. A 12 inch Tyzack saw with a nice brass back should be a good candidate for me to convert to a 10 tpi rip. If I can get this right maybe I'll make a new handle and post it afterwards. I got this saw at a second hand store and I prefer the old style handles over the original. Any thoughts on where I could find a pattern for a Kenyon style handle?

Jim

Mike K Wenzloff
01-12-2009, 8:58 AM
Jim,

Personally, I love 9 and 10 ppi rip-filed tenon saws. However, you might find that 10 ppi is a bit coarse for a 12" length blade. In general, a coarser saw favors a longer one.

But the beauty of doing your own toothing is that if that generalization holds true for you, then you have the ability to redo it. It's always faster the next go round.

Take care, Mike

Jim Paulson
01-12-2009, 12:44 PM
Mike,

I like what you said about the flexibility of the tooth size vs length. Alan had similar thoughts about the coarseness of the 10 points. I am hoping it is like making your own wooden hand plane (Krenov style), once you do it you have more freedom with your woodworking. I am embarassed to say http://www.sawmillcreek.org/images/icons/icon11.gifthat I've used my cross cut back saw one too many times for ripping with frustrating results. Hopefully, this will give me the means to add a few rip saws to my tool box. I also love to refurbish old tools.

So far so good on the filing and those 10 point teeth (10 tpi/11 ppi) seem small enough for me now. http://www.sawmillcreek.org/images/icons/icon7.gif Thanks again on your comments.

Jim

Leif Hanson
01-13-2009, 12:19 AM
I got a reply from Leif, he's gonna look at it today. He thinks the database got munged up somehow.

Yes, and what fun! Worse yet, I think it was all my fault... Ended up going through a full site upgrade to repair it. Anyway I've got the thing up now, it should be up to stay (famous last words). There'll likely be some issues and difficulty finding things while I rebuild the menu system. Still researching the best method to use...

If you have the patience, it's nothing to file new teeth - and a great skill to have. But if you know somebody with a Foley - well, that is just a bunch easier. Problem is not everybody has one or want to do it for you for next to nothing...

Mark Harrell at technoprimitives.com gets high marks... and has set prices. You might give him a try if you don't feel up to the task. I think it's like $45 for retoothing.

Leif

Alan DuBoff
01-13-2009, 1:19 AM
Problem is not everybody has one or want to do it for you for next to nothing...
The later certainly explains me. ;) What I found out is that the Foley equipment is so crude that you can't easily set it up and get the proper rake the first time, or that it doesn't stamp them properly with small teeth so you need to make another pass.

In the past I offered to do this for folks, but what I have found out is that it is not worth my time to offer the help to others, as I can easily spend more time than I would want doing so. It is not that I don't want to help others, just that it's hard to calculate how long it will take to stamp teeth by the time you get a plate that your happy with. At least that is how it is for me.

The Foley equipment is not without fault...whoever designed this stuff had their head on sideways...

Jim Paulson
01-13-2009, 7:27 AM
Hi,

Thanks Lief for getting your site back up and you and Alan for you comments. I gather as well that besides cost and availability, the trick with the Foley equipment is also being able to obtain the necessary accessories like the various parts (carrier) that hold the saws.

Being a woodcarver I found it helpful to use my opti-visor, but the 2x (i think) lense was not quite enough for me to see the teeth clearly. Any thoughts on using magnification? I found it hard enough to see the teeth at 10 tpi. I definitely would need something more powerful for finer teeth.

Jim

Alan DuBoff
01-13-2009, 1:05 PM
Thanks Lief for getting your site back up and you and Alan for you comments. I gather as well that besides cost and availability, the trick with the Foley equipment is also being able to obtain the necessary accessories like the various parts (carrier) that hold the saws.
Jim,

The Foley equipment requires that you have a carrier, this is the piece that holds the saw blade, you clamp the blade to the carrier to secure it. The carrier has some cross-bars, which sit about 3/4" above the carrier bar itself, this allows for the handle to be left on the saw when you sharpen, providing 3/4" for clearance of the handle on that side of the blade, if that makes sense. It is about half the thickness of the handle, so 3/4" works on most all saws I have seen.

Then you need to attach a ratchet bar to the carrier, this gets attached to the opposite side of the carrier. It is these ratchets that get lost over time, and separated from their equipment. Also, multiple machines work with the carrier/ratchets, so even to use one machine you need them, but more than often people have one set of carriers for multiple machines. The retoother is yet one machine, there's also a auto filer, and an auto setter. In theory you can shape (retoother), set (power setter), and sharpen (filer) with the various machines. For my taste, the only machine that has been worth any value is the retoother to stamp the teeth, I set and file by hand.

The ratchets will handle for about 4 ppi up to 16 ppi. In total there are about 8 or 9 ratchets, as they do multiple sizes. One would think that going from 1 tooth to 2 teeth on the ratchet would half the number of ppi, but it doesn't work like that, and I was confused over this for the longest time...but a fellow galoot explained to me why. When you measure ppi, you measure both teeth on the end, so there are more teeth in ppi than tpi. The Foley ratchets work on ppi. When you half the number, you end up with a half tooth for the end tooth, and that is why the difference. The 16 ppi ratchet will also do 8 1/2 ppi, it's the end tooth that accounts for the extra half, if that makes sense. This was bugging me why the mathmatics didn't work out even and half the number, but that is the reason, the extra tooth. As an example, the 15 ppi ratchet will also stamp 8 ((15 / 2) + 1/2), the 14 ppi will stamp 7 1/2 ((14 / 2) + 1/2), etc...some ratchets will stamp 3 sizes, such as 13-7-4, but you can only get a 3rd ratchet on some. I believe that has to do with the 2nd value in regards to the 1/2 tooth, so I suspect it needs to be on the even number if that makes sense.

Here's some pics from another thread.

Carrier gages allow you to set the blade on the carrier, ignore the teeth on the wrong side, I just did this for a picture, you would cut the teeth on top.
http://www.sawmillcreek.org/attachment.php?attachmentid=102654&d=1228337563

The ratchet attaches to the opposite side of the blade:
http://www.sawmillcreek.org/attachment.php?attachmentid=102655&d=1228337586

The carrier going through the retoother, the ratchet advances the carrier as the die stamps the teeth. The ratchet determines the ppi of teeth which are stamped:
http://www.sawmillcreek.org/attachment.php?attachmentid=102656&d=1228337607



Being a woodcarver I found it helpful to use my opti-visor, but the 2x (i think) lense was not quite enough for me to see the teeth clearly. Any thoughts on using magnification? I found it hard enough to see the teeth at 10 tpi. I definitely would need something more powerful for finer teeth.
You need to be the proper distance to the teeth. I use 2.5x lenses in the OptiVisor, and it works well for me, but they make a 3x also. The lenses are replaceable so you might consider a stronger set of lenses that will make it more comfortable for you. I can do 10 without magnification, but start using it around 13-14 ppi. Very hard for me to sharpen without magnification on any of the smaller teeth.

Jim Paulson
01-13-2009, 3:45 PM
Alan,

I plan to stick with it for now. I trust that filing/retoothing/sharpening will come easier with time. I'll work on magnification, better lighting and also keeping track of the teeth I've already filed. Seriously, overall my saw looks good for an initial attempt. I have to chuckle though when I see a little wave in the heights of the teeth and some variations in the size of the teeth. I guess it adds character. The good news is that the saw at least can cut. It will be good enough until the next time when I get around to leveling the teeth again and tweaking it some more. At least I'll know which teeth to go easy on, the low ones :).

Great pictures of the Foley retoother. Unless the patents still apply, wouldn't you think someone would remanufacture those ratchets? Maybe there isn't enough of a market.

Take care,
Jim

Alan DuBoff
01-13-2009, 11:32 PM
I trust that filing/retoothing/sharpening will come easier with time.
Absolutely! I think you will find that if your patient you can shape the teeth good. Just remember to be patient, don't take too much off in a pass, so you can compensate if they get out of proportion.

better lighting
This is the single most overlooked area, IMO. By having proper lighting, it will help tremendously. If you have natural lighting during the day, all the better, IMO.

I see a little wave in the heights of the teeth and some variations in the size of the teeth. I guess it adds character.
It does add character, but more importantly you will find that the saw will still be sharp, so there is no reason to fear that one would ruin the saw, yet so many do...just joint and resharpen.

Great pictures of the Foley retoother. Unless the patents still apply, wouldn't you think someone would remanufacture those ratchets? Maybe there isn't enough of a market.
Foley still owns the rights and sells them. They charge $70/each for them, and don't have all of them anymore, but what they have can be had by them. You could make your own, would be a lot of work but someone that understood gears really well, would probably know which cutter is needed, I'm not sure myself. You will still need some type of linier indexer also to space them correctly.

Foley doesn't sell the 16 ppi anymore, so that is the most sought after, IMO.

The other thing is that you can still find the ratchets on ebay, and while they go for decent change, they are way cheaper than buying from Foley at $70/each. The ratchets are the deal breaker for most of the equipment. Without them you can't use them.

Take care,
Jim[/quote]

Daren K Nelson
01-14-2009, 7:10 AM
The ratchets are the deal breaker for most of the equipment. Without them you can't use them.



I know I get contacted at least once a month by people wanting to buy just the carriers and ratchets. Their note always starts "I bought this (retoother/filer) at an auction for $XX (cheap) but it did not come with the carriers"...Yep you just bought a $XX boat anchor.