HSS cutting tips and turning tool making?

[CHJ]

Yes that's the animal.

 

[mike s]

another one to try

 

[Silverbirch]

I`ve just finished making a set of hollowing tools, scraper style, with rectangular section HSS tips epoxied into 1/2" round tool steel shafts. I largely followed the instructions in David Ellsworth`s book. I`ve yet to try them out, but they`re sort of MK2 versions of some I made previously, so I expect them to work OK, perhaps with a bit of tweaking. I`ll post a pic tomorrow.
I think making and using your own tools can teach you quite a lot and should make you more aware of what to look for if and when you decide to buy commercial ones.

Ian

 

[NetBlindPaul]

Silverbirch,
By the way you can braze (braze weld) or silver solder tool steel quite successfully if careful.
The epoxy will be flexible and "may" allow the tip to vibrate giving you chatter, it also may not, it may improve things by acting as a damper!

 

[mike s]

silverbirch, where did you get the hss cutters from?

 

[jasonB]

Round, square & hex HSS

http://www.arceurotrade.co.uk/Catalogue ... l-Toolbits

Old centre drills make good tooling

J

 

[mike s]

thanks for the link jason
the round cutters i can hold in a drilled hole, how would you hold a square section?

 

[jasonB]

Square hole

If you are not set up with a square broach then just drill a hole to the corner to corner size of the square toolbit and the grub screw will keep it from rotating.

J

 

[Silverbirch]

Hi Mike,
These are the homemade hollowers which I`ve just finished making, which I mentioned in an earlier post.
13" X1/2" silver steel shafts(Ebay), copper plumbing fittings for ferrules, 3 HSS tips ground from a single rectangular piece similar to those in Jason`s link above (I got mine from the Ashley Iles stand at a show.)
Holes bored in the shafts with a cobalt drill, fixed in place with epoxy.
The bent tool was heated with a butane torch and bent in a vice (hard work!)
I`ve just tried them out briefly today on some scrap. The hooked version chatters a bit, possibly due to the toolrest overhang necessary to clear the bent section and the length of the tip which is perhaps a bit too long. Perhaps also, as Paul suggests, the epoxy allows a little flex. The other two tools seem to perform well and leave a good finish. An advantage of an epoxy fixing over brazing is that the join can be softened by heating to allow removal of the tips should this be necessary. Another advantage for me, is that I don`t have the equipment or the know how for brazing.
If you were going to make tools like this, I`d suggest grinding the tips to final shape before fixing in the shaft. It`s much easier to control the operation that way. Sharpening thereafter will be by hand with a diamond file.
Total cost all in for the three tools including timber for the handles was about £30, so well worth a shot, I think.

Hope this is of some help,


Ian

 

[mike s]

im going to buy 4" long 1/4" square bar and 4" long 1/4" round bar from the link jason gave
have you had any problems from this company? roughly how long is the postage?
tomorrow im going to the scrap metal place and getting 2 meters of 1/2" mild steel round bar
i will pretty much copy silverbirch's shapes (sorry) and keep the leftover materials for other tools in the future
if necessary i will heat the mild steel until cherry and quench it in water to harden it (that will work, right?)

im looking forward to making useful tools that will save me £

thanks everyone for all the tips and suggestions

 

[CHJ]

.....i will heat the mild steel until cherry and quench it in water to harden it (that will work, right?)...

No it won't. you cannot harden the average Mild Steel by heating and quenching, it's carbon content is too low.
It has to be case hardened by exposing it to a high carbon content substance while heated to cherry red so that it absorbs more carbon in the surface, this then when quenched will provide a harder skin.

EN8M and above steel can be hardened,but I doubt that a local scrap yard will have any idea as to specification of their holdings.

Re sizes, HSS, 3/16" would be a better size and give you more thread room for fixing grub screw.
Mild Steel Bar 5/8" dia or square will give you more rigidity and should not need hardening.

 

[jasonB]

ARC are good should be next day del.

As said you can't harden MS and even if you could it would then be brittle and need tempering which would be difficult over a long length to do evenly.

You could always drill slightly off centre to give more thread depth for the grub screw. The advantage of using grub screws over epoxy is you can easily change bits from one that is ground with a rounded end, to a straight, to a pointed etc.

Best way to cut the HSS into say 1" lengths is a dremel cut off wheel.

 

[mike s]

i posted a WIP of the hollowing tool i have made
thanks again for all the help

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