The best powered scraper ever made?? Better than a Biax?

The Coburn No.1817 Type.1 is an old industrial power scraper from the 1950's.
There is not much about them on the internet, but the one thread on Practical Machinist had an Australian claiming they are the best scrapers ever made. Good enough for me :)
Thanks for watching.

[@Paul-FrancisB]

Great machine, that motor was made just 2 miles from where I grew up and my mum still lives in the year of the queens silver jubilee, thanks for the video and the trip down memory lane 🙂

[@RotarySMP]

Thanks for the feed back Well made motor an tool.

[@paulbyerlee2529]

Its funny how people find content producers on KZbin. I watched this video when it came out because I was considering making a power scraper at the time. I saw a couple of your videos after this but wasn't subscribed to your channel. I ended up rediscovering your channel about a year ago and have sub'd and watch your new and old video's religiously ever since. Keep producing great content Mark and I can't wait to see what you do next.

[@RotarySMP]

Thanks for supporting the channel Paul, I appreciate it.

[@mikemullenix6956]

Machines like this aren't made today. Made back in time when quality and function was at its peak. Finding one of these would be a challenge.

[@RotarySMP]

I thought the number on it is a model. It is actually the serial number. Looks like only a couple of thousand was the total ever produced. It is a cool machine.

[@davidb6576]

Thanks for the video! Nice to see another power scraper design, and its use.

[@RotarySMP]

Thanks David. I didn't realise No.1817 meant it's serial number till I reread the Practical machinist thread. www.practicalmachinist.com/vb/machine-reconditioning-scraping-and-inspection/power-scraper-best-ever-297727/ Since about 60 000 Biax's got sold, but maybe only a couple of thousand of Coburn's, no wonder they are nearly unheard of today.

[@capncharlie7894]

I had been dreaming of building something just like this ... with the stationary motor. Thanks for sharing. Amazing what is out there.

[@RotarySMP]

Thanks for watching. The old patent filing with a picture of the mechanism is in the Practical Machinist thead on it.

[@capncharlie7894]

@@RotarySMP Rotary, great tool, thanks for sharing the link to the PM site. Apart from Richard King raising the noise floor a few dB's, it was a good discussion. I *hate* running electric tools with geared motors ... too much noise too much vibration ... the Coborn was ahead of its time.

[@RotarySMP]

@@capncharlie7894 Thanks. It really is a nice machine. Having the honing plate make a s huge difference. I find I'm honing the edge every two of three passes, and it make a big difference when sharp. The flex shaft is not terribly flexible, but the jobs I have done have been on the bench, so it was easy enough to move the machine around.

[@fearlyenrage]

What a fancy thing. I like the clip very much.

[@RotarySMP]

Thanks. It is a very cool old machine.

[@fearlyenrage]

@@RotarySMP i did search the model but with no luck on ebay. It seems i have to build one or redesign a tigersaw. Still happy with the Schaublin? I have 2 102's

[@RotarySMP]

@@fearlyenrage I think Coborn must have had a very limited production of them. Would have been very expensive to produce. The Schaublin is awesome. The best machine I have ever owned. 102's are also really nice.

[@garysgarage101]

I love it. I’m just in the process of modifying a Sawzall. Need to get myself one of those PPI/radius gages.

[@RotarySMP]

I think there is a PPI radius gauge on Thingiverse, if you have a 3D printer.

[@samrodian919]

Nice old solid machine! Good old British manufacture, made about 5 miles from where I live. I'd love to find one of them at a car boot sale!

[@RotarySMP]

I got mine frmo a local guy I have become friends with. He gave me a good price for it.

[@davet9740]

G’Day, I’ve not had the pleasure of using either type, just a hand scraper but if I was in the market for a machine job I’d be looking for a Coburn. Great looking machine, thank you, Regards Dave

[@RotarySMP]

Thanks for watching. Certainly is a nice tool.

[@E1nsty]

You know what they say, a sparrow in the hand is better than a pheasant on the roof.

[@RotarySMP]

It is a nice tool.

[@FCleff]

VERY interesting! Thank you for the education. Cheers.

[@RotarySMP]

Thanks for watching.

[@misterfixit1952]

I finally got a 26" cast iron prism so I will finally be able to get my H618 surface grinder repaired. I've been looking on eBay for the last 2 years for an affordable small camelback or a prism or even a triangular straight edge but all of them I've seen were wickedly expensive. I finally bought a raw 26" Foster Featherweight prism and I'm going to machine and scrape it myself. People think refurbishing used equipment is a good way to save money, right up until they realize they need a surface plate, scraping tools, precision flats and all of the other metrology gear required to make things flat and true. In my case, my prize bargains, the $200 Boyer Schultz surface grinder and my new $300 Clausing 5914 lathe, only needed $1000 worth of gear to get started with the refurb project. Now if I can just find a deal on a tub of elbow grease, lol.

[@RotarySMP]

Nice find. The only thing I would advise on starting out scraping, is dont underestimate how fast carbide scraper blades go blunt. You dont really notice how much harder it is to remove metal till you lap again. The cast iron lapping wheel on my scraper drive is a god send. Consider whipping up something like this. kzbin.info/www/bejne/fYClpXtqopeHj9E

[@hinz1]

It looks a lot smoother than a Biax, but I think a lot comes down to how well the blade is sharpened, what kind of cast iron you're scraping, how good the DIY scraping blades are....

[@RotarySMP]

Thanks. In the original patent, it is mentioned that the handpeice should have sufficient mass to provide some inertia. I don't think it is lighter than a Biax.

[@chadr00]

Hello, how did you blue the feet? Is there some way to do it without a large enough surface plate or straight edge that spans the feet? Thank you.

[@RotarySMP]

The fit across the diagonal of my surface plate. I don't know of any other way to easily get them in a single plane.

Damn. Its eating metal. Giving up on my doggy built.

[@RotarySMP]

Do you have a way to hone the edge of your carbide often? Like Stefan Gotteswinters one here?: kzbin.info/www/bejne/fYClpXtqopeHj9E Having the cast iron lapping plate on the Coburn is a real help, as you need to hone/lap those scraper blades frequently.

[@jamesmanoni]

Hey man he didn't have a second one lying around did he?

[@RotarySMP]

I thought that No 1817 was a model number, but it turns out it is the serial number. It looks like Coborn only made a couple of thousand of these over the decades they were in production. Thanks for watching.

[@jamesmanoni]

@@RotarySMP Would ya sell it?

[@RotarySMP]

@@jamesmanoni No sorry.

[@emeltea33]

Internet tough guy here. This lacked scientific rigor. Would be nice to see how similar parts would have faired in just the caustic, but without baking. Thanks for the video though (seriously)!

[@RotarySMP]

Caustic? Baking? in my the Coborn video? I can't remember talking about caustic or baking in this one sorry. But I am sure it lacked scientific rigor :)

[@safeaegis]

nice

[@RotarySMP]

Thanks. It is a pretty cool and rare machine tool.

[@safeaegis]

@@RotarySMP That's right, a very interesting tool. Surprisingly, KZbin has not previously offered your videos. The topics of our channels are similar. A little CNC machine tool construction, a little tool work, precise mechanics, machine tool restoration, scraping, etc. Well, now watch your videos, sure many useful shows. Thank you for your experience

[@RotarySMP]

@@safeaegis I'll never understand the KZbin algorythm. Sometime a vide oI make I think is pretty weak and gets pushed by YT, other videos I am pretty proud of sink like a stone. Did you stop making videos?

[@safeaegis]

@@RotarySMP This year has been quite busy. I finished the CNC lathes and a friend bought them from me ... So I decided to make a couple more (I'll definitely leave one to myself!). I made a video about making lathes, but I won't find time to mount everything in a dozen series ... Still need to complete the order, then repair the manual lathe (had to glue zedeks and correct the geometry). Then I plan to make another "big" portal CNC machine for my own needs. Well, then there will be cast iron lathes and milling machines. Everything is going according to plan, but there is not enough time. While developing my instagram (there in my opinion short videos without editing is normal. instagram.com/mikhailzakruzhetskii/ I do not plan to stop, I will soon start editing videos on KZbin as well.

[@Versosurma]

I think that machine scraper is good after use but with hand tools you always have that feel there what it is doing high spots etc with machine it is harder

[@RotarySMP]

For finer parts I would probably also do a final spotting with a hand scraper, but for a simple static interface this will be good enough.

[@mikeslayer5926]

VERY NICE ! made back when ya put quality into your work and built to last I needed a die grinder just out of high school and couldnt find a new one ,let alone afford one,...I ran across an old Sioux die grinder from the 50's early 60's thick aluminum housing and every wearable part able to be replaced easily I replaced the cord put in new brushes cleaned the heck outa the switch, and found an assortment of NOS collets, that was in 1983 she still ports and polishes automotive heads like she was brand new good job , keeping the old ones working Mike

[@RotarySMP]

Hi Mike, yeah this is a pretty device. The castings are quite heavy in the hand piece.

[@akfarmboy49]

I think Colborn made another power scraper that had a sweeping arc action instead of the reciprocating action

[@RotarySMP]

I bet is very rare. They made these things to last though.

[@capncharlie7894]

at 1:40 ... from the side view it appears the scraper was meant to also be used 'backwards' and I am going to assume from a design standpoint that is why the 'front' handle is angled the way it is. It's the angled recessing for the blade carrier that is symmetrical that makes me believe this.

[@RotarySMP]

Thanks fro watching. Not sure I follow that. It works just like a Biax.

[@akfarmboy49]

Here is what I would do with that tool I would put 18 volt motor on it from cordless drill or die grinder or a router motor because it has variable speed dial on motor. It is a fun old school tool that works for you keep it.

[@RotarySMP]

I am pretty happy with it as it is. But you are correct, if that flex shaft fails I’ll put such a motor on it

[@StanislavG.]

Thanks for the video! I do scraping as a side job for a few year now (got an old Biax actually), i've seen pretty much anything on the market, but this thing, with the grinding wheel and the massive body looks extremely cool! Gotta love the old-timey stuff :) p.s. I think the idea of a separate motor stems from the industry's "conservatism" rather than shortage of alternatives. You could get any handheld power tool back then, but remember, as resent as at the 50's most big factory machines were still driven by a line motor, so this "big stationary unit to drive an appliance" paradigm was very much the norm for industrial equipment.

[@RotarySMP]

Thanks for watching. The coborn really is a cool machine. On my minilathe project, a lot of the parts I scrape are tiny, and I have been hand scraping, but having that lapping wheel on the coborn always available means I touch up the carbide blade really often, and you sure notice how much better they cut when freshly lapped.

[@StanislavG.]

@@RotarySMP I hone the insert without even noticing it most of the times :)) I use this diamond stone thingy, and it doesn't need much if you do it often as you should. Sorry for asking, but how much did it cost you?

[@MakarovFox]

nice

[@RotarySMP]

Thanks

[@HairyNumbNuts]

I wonder if that motor is the right RPM? The scraping you show looks too heavy (I'm NO expert, I'm trying to learn). How can you get points of bearing? It looks like it cuts deep channels across the surface with no original surface between them.

[@RotarySMP]

Thanks for checking out my video. It is a normal 4 pole induction motor so about 1280 stroke/minute. Modern Biax are 0-1800SPM. The older ones would have been the same soeed as mine. You do need to move it quite fast to get a checkerboard pattern. It is definitely a practice and muscle memory thing.

[@samrodian919]

RotarySMP I think if that was a two pole motor you'd have 2400 rpm to play with and that might be a better way of getting a light touch on it if you had a speed controller. You mentioned a VFD I know they are used to run and control a 3 phase motor, but do they make VFD's to run single phase motors?

[@RotarySMP]

@@samrodian919 This is a three phase motor which has a capacitor to fake a second phase so it can be run off three phase. I haven't hook up a VFD to it. When dive bombing the spots, you get a feel for it, and dont really need to slow it down.

[@tonyray91]

Looking at the style of the motor I’m sure it’s not the original so the rpm may have been different, anyway it looks like the replacement was done well and with a VFD it won,t matter. Not having the noise of a universal motor and the inbuilt lapping unit makes it a winner.