# Welding hss



## graduate_owner (5 Mar 2016)

Hi all,
I was thinkng of making some woodturning scrapers by welding a section of hss to a secton of mild steel. Is this feasible? I was thinking of mig welding - would that do the job? The welded area wouod be about 4" from the workng tip.

If mig is possible, what wire / shielding gas would I need? If not mig then could it be done with tig, and again what gas / filler rod would I need? ( I may be able to get access to a tig welder plus operator).

K


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## dickm (5 Mar 2016)

Not a kowledgeable answer at all, but my gut feeling would be not to do it. Joining dissimilar metals, just not sure how strong the weld would be, even with careful choice of electrode and a skilled welder. But someone with more metallurgical knowledge will be along and can give an authoritative answer. Years ago, when young and foolish, I welded a broken carbon steel bowl gouge and it survived, but would certainly not do it now.


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## marcros (5 Mar 2016)

i would doubt that you will save any money if you were to make them this way. i would just buy an unhanded one from ashley iles.

if you really wanted to make a tool, I would make a carbide tipped tool. plenty of tutorials around for that.


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## Rorschach (5 Mar 2016)

Usually HSS or carbide is silver soldered onto mild steel for making tools. Can't say for welding.


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## blackrodd (5 Mar 2016)

Rorschach":ldxtnrmt said:


> Usually HSS or carbide is silver soldered onto mild steel for making tools. Can't say for welding.



As above, I would have thought brazing or silver solder to join HSS and Mild steel, in the same way that TCT blades are just a strip of TC, and brazed to the mild steel carrier.
We used this method to join the large bandsaw mill blades together after they had been "lapped" or tapered.
Heat in the right place and a good quality flux are among the important factors.
Rodders


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## Phil Pascoe (5 Mar 2016)

Yes. Also if you have a lathe or a mill, the section required for (most) scrapers is large enough for a little mechanical jointing as well, like a small t & g, which would take impact a bit better. For the bother though it's probably cheaper to braze or bolt on tips to a piece of BMS. (imho  )
Actually, thinking about it with a scraper you could well have an overhang of four inches - not a good place for a joint, right on the pivot.


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## graduate_owner (6 Mar 2016)

Thanks gents,
I think it will be hss tips on a mild steel shank, either brazed or fixed with a bolt. I read somewhere that a sharpened masonry bit can be used for drilling hss.

Has anyone tried drilling hss with cobalt steel drill bits?

K


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## Lons (6 Mar 2016)

graduate_owner":20lumcsu said:


> I read somewhere that a sharpened masonry bit can be used for drilling hss. Has anyone tried drilling hss with cobalt steel drill bits?K



Didn't work for me!

I just received a solid cobalt bit I ordered but haven't tried it yet. I need to drill holes in a number of 3mm thick HSS spindle moulder block cutters. I'll let you know how I get on once I get around to it.


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## graduate_owner (6 Mar 2016)

Lons, I will be very interested to hear how you get on.

K


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## woodpig (6 Mar 2016)

if you want to make some cheap tools, as said earlier, just buy some carbide inserts and bolt them to some mild steel bar. Quick and cheap to do and the carbide will stay sharper a lot longer than HSS. You can even touch them up on a diamond plate when they dull.


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## chipmunk (6 Mar 2016)

You might be interested in this thread...
https://www.ukworkshop.co.uk/forums/homespun-turning-tools-again-t73942.html?hilit=TCT tile

A cobalt drill bit probably won't get through HSS because I think it'll just be 8% Co (M42) which is only slightly harder than M2 HSS - but a TCT spear-point tile drill will get through (slowly) although it'll likely chip the TCT on the way through. This is to be expected with uncoated TCT when machining steels.

Another possibility would be to use a TiAlN coated solid carbide end-mill which is less likely to chip but you'll need to have a milling machine or sufficiently rigid set-up to do the drilling otherwise it too will chip. 
http://www.arceurotrade.co.uk/Catal...Carbide-End-Mill-Standard-Length-TiAlN-Coated

The other possibility is to grind a slot in the back of the HSS cutter with a Dremel cut-off wheel in the same way as Siragas scraper tips on the Hamlet Big Brother. 







HTH
Jon


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## Rorschach (6 Mar 2016)

I have turned HSS using carbide, never tried drilling it though.


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## graduate_owner (6 Mar 2016)

TiAlN does sound interesting. £8 for a 5mm milling cutter on Arceurotrade seems reasonable if I can use it to make several tools. I have a milling machine in my workshop so rigidity is not an issue. My plan now looks like being - cut a section of hss from a bar using an angle grinder after shaping and drilling, and screw to a section of mild steel which has a flat milled on it. Chronos sell 5 lengths of 4" long 1/2" square hss for £22. That would make a lot of scrapers. Half inch square is not ideal but I suppose rectangular section of 1" x 1/4" would be similarly priced.

Things look promising.

K


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## Lons (6 Mar 2016)

graduate_owner":1eclsfw5 said:


> Lons, I will be very interested to hear how you get on.K



My appologies, the old brain cells must be dying quicker than I thought.  

It's a solid carbide drill I bought not cobalt - this one: http://www.ebay.co.uk/itm/201320898755? ... EBIDX%3AIT


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## woodpig (6 Mar 2016)

Rorschach":3bwf4k3a said:


> I have turned HSS using carbide, never tried drilling it though.



I was surprised to hear this before. What sort of finish can you get?


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## Sheffield Tony (6 Mar 2016)

Aside from TCT cutting tools, most of the cases I can think of with a tool steel welded to a softer/cheaper steel are forge welded - laminated plane blades, axe bitt inserts and poll surfaces. Perhaps there is a good reason. 

I understand it, HSS like M2 has more complex heat treatment requirements than carbon steels, in particular involving SLOW heating. I imagine welds to mild sreel have a high risk of cracking and would require preheating ?

As hardening HSS is not so easy at home, I assume we're talking about a pre heat treated piece of steel. Surely brazing it would lose the temper. And doing it the other way around, heat treating it would most likely melt the braze.


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## chaoticbob (7 Mar 2016)

I've drilled HSS with solid carbide bits - they're good things to have generally as you can spot with them as well because they're so stiff. Provided you have a sufficiently rigid machine of course. I think I got mine from Cromwell.
I've never tried silver soldering HSS, but if the join is 4" from the business end you shouldn't have a problem with taking the temper from the HSS - but stick the end into a potato if you're worried. Works for me with silver steel anyway!
Rob.


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## Rorschach (7 Mar 2016)

woodpig":3ku7ts5l said:


> Rorschach":3ku7ts5l said:
> 
> 
> > I have turned HSS using carbide, never tried drilling it though.
> ...




The finish I got was superb (I turned the shank of an end mill to make an extension shaft), smooth and shiney, the chips however were coming off red hot and it was actually a little scary lol.


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## chipmunk (7 Mar 2016)

Lons":1e1yz5ga said:


> graduate_owner":1e1yz5ga said:
> 
> 
> > Lons, I will be very interested to hear how you get on.K
> ...



That looks much more up to the task 
FYI, most of the Sorby cutters use an M5 screw to hold them in place whereas the Siragas scrapers for the Hamlet BB use M6 screws.

Jon


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## Lons (7 Mar 2016)

chipmunk":298u3byb said:


> Lons":298u3byb said:
> 
> 
> > graduate_owner":298u3byb said:
> ...


I'll get the chance to give it a go sometime this week, workshop time a bit limited at the minute.

I did manage to drill 4 holes before buying this but it cost me 6 drill bits including 2 which I think were cobalt bought from that guy at Harrogate show who drills just about everything with them. Tried a spearpoint and several decent TCT masonary bits but poor results. I use my Meddings drill press which is rock solid and tried different speeds, dry and lubricated drilling
I have a Euro cutter block but a number of surplus pairs of cutters which are exactly the same fitting but no holes, the 2 I have managed to drill work perfectly so worth the effort even if I have to buy more drill bits.

Bob


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## Inspector (7 Mar 2016)

Sheffield Tony":v7qrk3ra said:


> Surely brazing it would lose the temper.



HSS was developed for metal lathes and milling machines because it retained it's edge even when it got red hot. As long as it isn't quenched after heating it will retain it's heat treatment. If quenched it gets microscopic cracks and the edges don't hold up. The same reason you don't dip a HSS tool off the grinder, even if it is blue, to cool it. Opposite of carbon steel which you should not allow to get hot enough to see a colour change. So braze away if you want.

Pete


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## Sheffield Tony (7 Mar 2016)

Inspector":2akfni73 said:


> Sheffield Tony":2akfni73 said:
> 
> 
> > Surely brazing it would lose the temper.
> ...



Are you sure ? The hardening and tempering temperatures are rather higher than carbon steel, but certainly M2 can be annealed by heating to red heat and cooling in air - I've done it and been able to file it afterwards. And this seems to agree:



West Yorkshire Steel":2akfni73 said:


> Annealing
> 
> Annealing is recommended after hot working and before re hardening. Heat the M2 high speed steel to 850°C at a rate of no more than 220°C per hour. Always hold at temperature for one hour per 25mm of thickness (with two hours being minimum). Furnace cool slowly. The annealed hardness achieved should be 248 Brinell or lower.


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## Inspector (7 Mar 2016)

I'll qualify my statement. Silver brazing / solder flows at approximately 1200F or 650C so is below the temperatures that HSS will loose its heat treat properties. So with the right type of brazing rod HSS can be brazed to a mild steel bar. Now if you take into consideration the cost of Silver Brazing Rod it is probably more cost effective to buy import HSS turning tools or use carbide inserts or HSS inserts that are drilled already. http://www.arwarnerco.com One could also drill a hole in the end of the mild steel bar big enough to put the HSS square or round bar into and hold it with setscrews and put a handle on it. Much of it depends on what tools and equipment we already have, what skills we possess and how much futzing time we have. I think it false economy to try and make HSS lathe tools if we have to go and buy a lot of stuff to do it.

I sit corrected.
Pete


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## Phil Pascoe (8 Mar 2016)

"One could also drill a hole in the end of the mild steel bar big enough to put the HSS square or round bar into and hold it with setscrews and put a handle on it."
If you go down this route, a set of taps (assuming you've a holder) and five 4.3mm drill bits are only just over £10 + a bit of p&P, and BMS is cheap. Even if you want to go upmarket 16mm stainless is only £16 - £20 per metre delivered. Cheap for what is only a holder, after all.


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## graduate_owner (8 Mar 2016)

Another possibility - what about using a length of ms for the main shank, say 1 1/2 x 1/4 or so. Take a piece of ms say 2 x 1/2 about 2" long and mill a slot in each end, one slot to fit the ms and one to fit a piece of hss about 2" long as the cutting edge. The slotted ms could be drilled to clamp the hss cutting end, and drilled or welded to fix to the main shank. Effectively joining the hss to the shank by surrounding both with a ms strap all round.

Any thoughts on this?


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## chipmunk (9 Mar 2016)

Another possibility is to follow the Simon Hope hollowing tool route.

I bought one of Simon's bent hollowers at £25...






and it cut very well indeed. So, I bought a set of M2.5 taps and some TCT 6mm round inserts (RCGT0602) intended for aluminium along with Torx screws and made my own straight cutters (just 6mm silver steel) and some holders with an M6 hole to mount them on my BB. You need a means to mill a flat bottomed 6mm hole for the insert to sit in along with a concentric tapped M2.5 hole which is pretty small.






HTH
Jon


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## Normancb (9 Mar 2016)

One of my colleagues in SMEE has machined HSS toolbits on a mill using solid carbide cutters to prepare them for our grinding course, but it's very hard on the cutter and produces a poor finish. I've got some early HSS turning tools from the days when HSS was a new idea - they are made just by silver brazing HSS plate into a mild steel blank and they work just fine - if I ever grind away all the HSS I'll just mill a new step and braze in a new bit.


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