Scratch Built Tool Gloat- Power Scraper

[mtraven]

Well folks, after several tangential projects I finally finished my power scraper. All questions, comments & critiques are welcome, after all, thats how these things get improved. I had a lot to say about this, rather than writing a novel, thought ya'll might prefer a video: power scraper

one question that kept coming back throughout this build, is why does biax use the mechanism it does? Most people have told me, "its for easy stroke adjustment". which it certainly does, but a system like mine is only marginally harder to adjust, there must be other reasons, anyone ? here is an excellent animation of how the biax works there is even an inventor model there you can play with if you have inventor (or use the free trial like I did).


now that I've finished that, obviously I'm going to have to build a power flaker. Could use some guidance on that. I understand the rolling motion the blade needs to make. though I would appreciate some numbers on that, degrees of rotation or something.

I've got some vague idea in my head of a reciprocating tool that has some sort of cam followers to roll the blade through each stroke. That's about all I got so far, so whatever ya got, throw it at me.

[JRouche]

Where did the the vid go? I was 1/5th into it. Some good machining going on there, imo. JR

[mtraven]

still works for me. anyone else having problems?

you tube link

[RB211]

Watched it last night. I subscribed.

[Mcgyver]

good project, well done.

[Dan Dubeau]

I bet you have the smoothest braking car around

[JoeLee]

I thought of making one that would adapt to my Sawz All. My plan was to be able to adjust the stroke by clamping the scraper further or closer to the end of the stroke.

JL.............

[RSG]

Good job! About the only time I could have used one is when I was building a bed turret for my lathe. Other then that it would sit on my shelf.

[mtraven]

I thought of making one that would adapt to my Sawz All. My plan was to be able to adjust the stroke by clamping the scraper further or closer to the end of the stroke.

JL.............

i think you'd find that the linear slide of a sawzaw is just too sloppy. off the top of my head, I dont think your method of adjustment would actually work. the fixed cam has to go though 360 deg of motion, no way around that. so if you essentially "choke up" on the shank, you'll just jam it out, instantly. Maybe you had something more complex in mind that addresses this, if not just scratch build it.


Good job! About the only time I could have used one is when I was building a bed turret for my lathe. Other then that it would sit on my shelf."

I don't have a surface grinder, so for me its use will be taking down what most would do with a grinder. But you're right, its a bit of a niche tool. That's what I couldn't justify buying a biax, but I do like having the right tool on the shelf for a job.

I seem to be drawing a blank here, what on earth is a "bed turret" ? I've heard of turret tailsocks & turret tool posts, but I have no idea what a bed turret is. sounds interesting, mind sharing a pic?

edit: just looked up turret beds, its mind blowing that I've never seen one of those before. omg, they are awesome. I wanted to change to a rack & pinion tail anyways & I've toyed with the idea of a tailstock turret (my tailstock is just to wimpy to do that properly). the bed turret solves all of that, gives a power feed and seems overall much more rigid than a tail stock.

still would like to see the one you built!

[mtraven]

Watched it last night. I subscribed.

you did! in fact you're the 1st subscriber of my new channel! we will have to remember that when I become a big you tube star! lol
thanks for watching.

[mtraven]

I bet you have the smoothest braking car around

lol, that took me a minute.

now you got me wanted to actually try scraping a rotor & seeing how it brakes. I know the grind on those is done to create lay lines perpendicular to the radial motion, i would think scraping could do that too?

[boslab]

I watched the video, clicked like ( the first is my mrs ) doorbell rung and forgot to bloody subscribe, I will remedy, I liked the video, no blasting rock music so that’s a relief, I love rock but find it a distraction if I’m listening to somthing educational.
I liked the mini shaper bull gear, cool
mark

[JoeLee]

i think you'd find that the linear slide of a sawzaw is just too sloppy. off the top of my head, I dont think your method of adjustment would actually work. the fixed cam has to go though 360 deg of motion, no way around that. so if you essentially "choke up" on the shank, you'll just jam it out, instantly. Maybe you had something more complex in mind that addresses this, if not just scratch build it.


Good job! About the only time I could have used one is when I was building a bed turret for my lathe. Other then that it would sit on my shelf."

I don't have a surface grinder, so for me its use will be taking down what most would do with a grinder. But you're right, its a bit of a niche tool. That's what I couldn't justify buying a biax, but I do like having the right tool on the shelf for a job.

I seem to be drawing a blank here, what on earth is a "bed turret" ? I've heard of turret tailsocks & turret tool posts, but I have no idea what a bed turret is. sounds interesting, mind sharing a pic?

edit: just looked up turret beds, its mind blowing that I've never seen one of those before. omg, they are awesome. I wanted to change to a rack & pinion tail anyways & I've toyed with the idea of a tailstock turret (my tailstock is just to wimpy to do that properly). the bed turret solves all of that, gives a power feed and seems overall much more rigid than a tail stock.

still would like to see the one you built!

The ram on my SawzAll has no play at all but the saw hasn't seen much use. I understand the motion / stroke of the fixed cam and that it can't be changed. That was the first thing that came to mind when I was designing the scraper attachment in my head. Knowing that the stroke of the saw was too long my idea of making it adjustable was to have the ram in the scraper head spring loaded to return. The further the attachment was moved away from the saws ram the shorter the stroke of the scraper would become. Of course this involved the saws ram hammering against the scrapers ram and the spring returning the scrapers ram. There would be a bit of hammering going on between the two rams and I thought of attaching a hard rubber or soft plastic disc to the end of the scrapers ram to soften the impact. However this design never go to paper, it's still in my head. It may or may not work as planned. The scraper blade would also be spring loaded on the horizontal plane.

JL...................

[Cleve C. Dixon]

Nice project! and a well done video too. you're going to have some pretty brake discs. Out of curiosity, what rpm is your motor doing? Thanks.

[mtraven]

Nice project! and a well done video too. you're going to have some pretty brake discs. Out of curiosity, what rpm is your motor doing? Thanks.

at full speed (12v), motor runs ~3500 rpm. The bevel gear reduces roughly 3.5:1, leaving me with ~1000 rpm at the cam, or 1000 strokes/min. I chose all that based on the biax having a max of 1200 spm. However, when you put it under load, it bogs down a bit & I have no way to measure my actual working speed, longer stroke length bogs down more. During the demo's in the video, I was @ about 3/4 throttle.