Building a model Drag Saw

[Brian Rupnow]

I like your Pinnochio saw! That blade is  just right for a model...

One last part to make..... the parking clamp for the blade.

 

Pete

Pete--Tell me more. I am not aware of a "parking clamp" anywhere.---Brian

[Ye-Ole Steam Dude]

Hello Brian,

The saw looks really great and you have done a wonderful job on all the construction and design. Looking forward to a working video.

Have a great day,
Thomas

[10KPete]

Brian, in posts #91 & 94 the pics show a deeply slotted block. In the first pic the blade is halfway in to the block. The next pic shows the blade/block positions in use.

Those ol' boys sure knew what they wanted on the machine! I'd only seen a few of these saws until this thread was created. There's nothing like old iron...

Pete

[Jasonb]

Actually to "park" the blade there is an arm that swings up and supports the linkage. When moving the saw about it needs to be held up so that it does not flop about, this picture shows it in use. It also shows how the wooden block rides up the angle bracket when the blade is raised. The wooden block only serves to guide th eblade at the start of the cut much like you would put your thumb against a handsaw to start it where you want, once the cut has started the saw blade will guide itself in the kerf it has created.



As does this Video, maybe you want to add the felling rig too

<a href="https://www.youtube.com/watch?v=Np2jED0HB3M" target="_blank">http://www.youtube.com/watch?v=Np2jED0HB3M</a>

[Brian Rupnow]

I am about to finish the final parts of this drag saw. If you have followed this post, you will know I am using a dog clutch which is engaged and disengaged by a lever. I have watched two dozen videos of drag saws on YouTube, and I'm still not certain of what type of clutch they used--it isn't clear in the videos. If anyone has detailed knowledge of how these original drag saw clutches operated, now would be a really good time to contact me and let me know. I have heard that they too have lever operated dog clutches, but I have also heard that they had friction clutches which gave them a gentler engagement than a dog clutch. If anyone has this knowledge, I would really appreciate a heads up.---Brian

[Brian Rupnow]

Jason--Thank you for that picture--I hadn't seen that before. Pete--That thing you are talking about is a saw guide to ensure that the saw starts cutting where you want it to.

[michaelr]

Hi Brian,
Enjoying your Drag Saw build, friction clutch for full size Drag Saw here may give food for thought. Mike.


http://www.herculesengines.com/hercules/NewManual/page_58.html

[Brian Rupnow]

Today I finished the dog clutch engagement lever. I realized that I had no way to put in the fancy scallops on each side that are shown in the cad model, because the handle is too long to swing on my lathe faceplate. If I can make it work properly, I may drill a series of cosmetic holes down the face below the hole that fits over the clutch diameter. Right now it works fine as far as engaging g/disengaging the dog clutch goes while the engine is not running, but there is nothing to make it stay engaged or disengaged. I have been warned that it is difficult to disengage the dog clutch while the engine is running. If that is true, perhaps I can just install a light spring that makes the lever disengage when no other forces are applied to it.

[Brian Rupnow]

Hi Brian,
Enjoying your Drag Saw build, friction clutch for full size Drag Saw here may give food for thought. Mike.


http://www.herculesengines.com/hercules/NewManual/page_58.html

Mike--Thank you. That is exactly what I was looking for.---Brian

[Brian Rupnow]

So--We have confirmation that everything goes round and round and up and down when the saw is operating but not actually cutting anything. Next step will be for me to tramp around in the woods behind my place and find a real 3" diameter log to cut.
https://www.youtube.com/watch?v=bzR7VE02jeo

[Brian Rupnow]

So--Today the drag saw cut it's first log. Everything went very well, except that I need to get a more aggressive blade. About half way thru the log, the saw seemed to take forever until I gave it a bit of extra weight from my thumb. A picture taken after the cut shows that there were two knots hidden away in the center of the log. Everything works as I hoped it would. My dog clutch worked as I had hoped. (I never made one of them before).  I will post another video after I get a more aggressive blade and put a spring on my dog clutch lever to keep it from rattling. I sell a complete set of drawings for this drag saw for $25 Canadian, but that does not include the engine.
https://www.youtube.com/watch?v=ylLgquXJfhQ

[Ye-Ole Steam Dude]

hey Brian,

Watched both videos and your machine is just fantastic. A blade with a bit more aggress teeth would surely cut a log faster. Beautiful job.

Have a great day,
Thomas

[crueby]

Fantastic!

[Kim]

That is pretty cool, Brian!  Fun video 
Kim

[Brian Rupnow]

I just went downtown and spent $12 of the Rupnow fortune on a saw with a really radical tooth profile on one side. Tomorrow we will see about mounting it on the drag saw. I did find out something today. Saws that have a handle which spans both ends of the blade are only .024" thick. Saws that have a handle at only one end are .036" thick.