Making a scraper tool

[bellyup]

Mornin' all,
I was given a tool-steel scraper disc by Harry at the Horsham U-Turn the other week and I an thinking I would like to attempt to make a scraper.
The only tool I have seen or used was a Sorby ( again at U-turn) and the shaft was a hefty little number - do they need to be that solid?
I'm assuming that a mild steel shaft wouldn't be up to the job and my choices are pretty limited out here for "off the shelf" bits but one thing we do have lots of out here are used shock-absorbers.
How do you think a shaft from a shocky would go for a scraper shaft and what would a good length be for the shaft and for the handle?
I reckon I can flat grind the working end of the shaft ,a'la Sorby and tap a thread to mount the disc ( about the size of a 10 cent piece)
What do you reckon? All advice appreciated.
Thanks,
Bruce.

[rsser]

Should work Bruce.

What's the shock shaft diameter?

I'd say 1/2" min and pref 5/8" would be best to cope with the stresses and minimise chatter.

If you could slide it into a bit of steel pipe and fix with a grub screw you could vary the extension to suit the job.

[new_guy90]

How do you think a shaft from a shocky would go for a scraper shaft and what would a good length be for the shaft and for the handle?
I reckon I can flat grind the working end of the shaft ,a'la Sorby and tap a thread to mount the disc ( about the size of a 10 cent piece)
What do you reckon? All advice appreciated.
Thanks,
Bruce.
you want to drill and then tap hardened spring steel :? i spot a flaw

[bellyup]

Ern,
The steel pipe idea is a beauty!! even if I have to sleeve the inside of the pipe to make it tight.
As for the diameter of the shafts well I think they vary from about 12mm for a small sedan to over 40mm for a heavy duty 4x4 shock.
How long would you make the shaft?
Bruce.

[bellyup]

Pat, I don't doubt that the shaft will be hard/hardened but I don't think it will be spring steel - at least I hope not

[new_guy90]

Pat, I don't doubt that the shaft will be hard/hardened but I don't think it will be spring steel - at least I hope not
oh ok got that just make sure you anneal it and its not harder than the HSS you are going to use to drill and carefully tap it

[Skew ChiDAMN!!]

Length? 8" to 12" should be more than ample.

After all, you're making a scraper and not a deep-hollowing tool, so should rarely see anywhere near that much hanging over the toolrest. :)

Really, the only reason too make it that long is so you don't have the handle blocking your view during use.

If you do plan on using it with some "serious" overhang, then the thickness of the shaft is more important than the length, to reduce chatter.

[bellyup]

oh ok got that just make sure you anneal it and its not harder than the HSS you are going to use to drill and carefully tap it

que?:?
Pat, tell me more about the annealing thingy.
Bruce.

[rsser]

Here's a design for a shock-absorbing handle ... prob overkill for a scraper. You could instead wrap adhesive handle tape around it, as for bikes, fishing rods and golf clubs.

http://www.artisticwoodturners.com/Resources/toolhandle.htm

[bellyup]

Morning all,
Thanks for the advice on making a scraper. Hopefully there are 4 photos attached of the finished tool. I basically made a copy of a Sorby tool. The shaft is 19mm mild steel that I hacksawed down the centre, cut off then filed flat. The shaft was then drilled and tapped with a 5mm allen key head screw (same size as chuck jaw screws so 1 less thing to find or lose!).
The handle came from a branch found at the green tip, Eucalypt of some sort.The collar comes from the plumbers supply shop - 25mm copper coupling cut to half length.
The turned handle was drilled out with a 20mm speed bore to a depth of about 150mm and the shaft was cemented into place with Araldite.
It's a hefty little beast but I don't mind that, seems to make the process of scraping"smoother". The centre of balance is at the collar - I don't know if thats where it usually is ?
Does it work? - Yep, works like a beauty!! The thing that really helps me is the fact that there is only a very small cutting surface so catches are greatly reduced, especially when you're deep inside a bowl.
Photo 4 is the sharpening jig that i quickly knocked up (scrap threaded rod) with a 5mm tapped hole in the centre of the rod to hold the disc and the other end is rounded off to fit into the Wood-cut jig.
Total cost of project - less than $10.
P.S. I reckon i can turn it into a "chatter tool" by screwing a broken and shaped hacksaw blade under the 5 mm bolt - hmmm what size is the retaining hole on a hacksaw blade?
Thanks all for your advice.
Bruce

[rsser]

Nice work Bruce.

[Paul39]

Bruce,

As you are overrun with shock absorber shafts, try grinding whatever shape suits your fancy on the end of one and trying it out.

Let us know how it cuts, and how long before needing resharpening.

I also like a heavier tool as long as there is room to get it into the bowl.

[bellyup]

Thanks Ern. I'm pretty pleased with it.
Paul, I'll do that. Waiting on a mate to get around to cutting them - out here that could take weeks!!
Thanks bruce.