# Can HSS endmill mill down Chinesium tool steel?



## stioc (May 22, 2019)

I got a Chinese 1/2" carbide insert tool bit holder for my lathe (parting tool actually), unfortunately it sits about 2mm (.08") too high from the centerline even with my AXA tool holder cranked all the way down. Before I dull or break my endmills thought I'd ask if these cheap tool bit holders can be milled down with HSS or Cobalt end mills? If not, what's the best way to mill it fairly flat? I have a bench grinder, 1" belt sander with a 5" wheel as well as a Dremel flex shaft toolpost holder for the lathe. As I'm thinking about it may be holding the tool bit in the 4 jaw chuck and using the Dremel flex shaft with an abrasive wheel would be better? IF I can hold it in it the chuck somehow.


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## benmychree (May 22, 2019)

Try it with a file, if it files fairly easily, it will cut with an end mill at reduced speed, I'd start at about 30-40 FPM cutting speed, use cutting oil.  I just recut 5 tool holders today, but surface ground them about 1/8" undersize to 1/2".  I have milled others, but they were pretty hard, I used a carbide indexable end mill, that at reduced speed.


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## darkzero (May 22, 2019)

I agree with John, test it with a file. Some China tooling is not that hard & only case hardened. I've done it with a HSS-Co end mill, didn't last long but got the job done. I've tried milling some quality USA hardened tooling before, it just laughed at the HSS end mill.

I'd just buy a carbide endmill, $20 or less shipped from ebay or less depending on the size.


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## martik777 (May 22, 2019)

These work well: https://www.aliexpress.com/item/327...lgo_pvid=aab84b0b-cf84-425c-8cdd-fa24cb5fb6a7 

I also made an angle grinder grinding wheel fixture I use on the mill to "surface grind"  hardened material.


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## stioc (May 22, 2019)

Thanks all, I'll give those suggestions a shot. I've been meaning to buy one of those indexable carbide endmills for a while so may be this project makes it a 'must have' lol

I'm surprised no one said to use the Dremel in the toolpost.


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## MrWhoopee (May 22, 2019)

I just use a small flycutter with a cheap brazed carbide in it. Works every time.


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## RJSakowski (May 22, 2019)

If the difference is small, Shars sells an 250-101-XL tool holder for 5/8" tools on an AXA QCTP. The floor of the slot is slightly lower than the standard AXA tool holders.


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## stioc (May 22, 2019)

MrWhoopee said:


> I just use a small flycutter with a cheap brazed carbide in it. Works every time.



I've done the same thing with the left hand indexable carbide tool bit in my flycutter with excellent results. However, after seeing some carnage from unbalanced tools like the flycutters I reallly try not to use it if I can help it. A knock off of the Tormach shear hog style is what I want to buy.



RJSakowski said:


> If the difference is small, Shars sells an 250-101-XL tool holder for 5/8" tools on an AXA QCTP. The floor of the slot is slightly lower than the standard AXA tool holders.



That's good to know, thanks!  If I can't skim a few mms off of the tool bit I'll get one of those tool holders.


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## stioc (May 22, 2019)

darkzero said:


> I'd just buy a carbide endmill, $20 or less shipped from ebay or less depending on the size.


Will, do you have a recommendation or have had good luck with any particular ones?


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## martik777 (May 22, 2019)

I linked a carbide end mill in post #4 (the 6mm for $4 works great):
https://www.aliexpress.com/item/32798922280.html?spm=2114.search0604.3.37.1dea3b11dh1gHT&ws_ab_test=searchweb0_0,searchweb201602_6_10065_10068_10130_10547_319_10059_10884_317_10548_10887_10696_321_322_10084_453_10083_454_10103_10618_10307_537_536,searchweb201603_52,ppcSwitch_0&algo_expid=aab84b0b-cf84-425c-8cdd-fa24cb5fb6a7-5&algo_pvid=aab84b0b-cf84-425c-8cdd-fa24cb5fb6a7


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## darkzero (May 22, 2019)

stioc said:


> Will, do you have a recommendation or have had good luck with any particular ones?



Not really, I don't stick with any particular brand name if that's what you are asking. I just buy whatever is USA made & haven't had any bad experiences with any of the ones I have bought. I have heard that Chinese carbide endmills are pretty decent compared to the quality of many Chinese HSS end mills. I haven't tried any myself though. Mainly cause I don't want to wait for shipping from China for an endmill & I don't use metric sized end mills.


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## stioc (May 22, 2019)

martik777 said:


> I linked a carbide end mill in post #4 (the 6mm for $4 works great):
> https://www.aliexpress.com/item/32798922280.html?spm=2114.search0604.3.37.1dea3b11dh1gHT&ws_ab_test=searchweb0_0,searchweb201602_6_10065_10068_10130_10547_319_10059_10884_317_10548_10887_10696_321_322_10084_453_10083_454_10103_10618_10307_537_536,searchweb201603_52,ppcSwitch_0&algo_expid=aab84b0b-cf84-425c-8cdd-fa24cb5fb6a7-5&algo_pvid=aab84b0b-cf84-425c-8cdd-fa24cb5fb6a7


Thanks, I saw that and I actually added it to my cart but my most recent order from BG and Ali took almost 4 weeks to arrive even with the priority shipping. So I was hoping to grab something locally. 



darkzero said:


> Not really, I don't stick with any particular brand name if that's what you are asking. I just buy whatever is USA made & haven't had any bad experiences with any of the ones I have bought. I have heard that Chinese carbide endmills are pretty decent compared to the quality of many Chinese HSS end mills. I haven't tried any myself though.


OK thanks! I was wondering if you were suggesting the indexable ones or just the regular endmills.


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## darkzero (May 23, 2019)

stioc said:


> OK thanks! I was wondering if you were suggesting the indexable ones or just the regular endmills



Oh no not indexable, just regular end mills. I just have a RF-45 style mill, I prefer regular end mills over indexable end mills. I do have a 1" 4 flute indexable end mill but I don't use it much. I use 1/2", 3/8", & 5/16" end mills the most & sometimes 9/16". I do have a few 5/8" & 3/4" end mills but I never use them.


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## Buffalo21 (May 23, 2019)

RJSakowski said:


> If the difference is small, Shars sells an 250-101-XL tool holder for 5/8" tools on an AXA QCTP. The floor of the slot is slightly lower than the standard AXA tool holders.



Good post

I just measured the bottom flange on the 250-101XL tool block, its approx .402”, the standard 250-101 tool block’s flange is approx .435”. I measured 6-8 of the standard blocks, all of them fell in the .433” to .435”, so the .435” was about average. On the 6 XL blocks, I checked, ranged from .400” to .404”, so .402 was about average.


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## stioc (May 23, 2019)

Buffalo21 said:


> Good post
> 
> I just measured the bottom flange on the 250-101XL tool block, its approx .402”, the standard 250-101 tool block’s flange is approx .435”. I measured 6-8 of the standard blocks, all of them fell in the .433” to .435”, so the .435” was about average. On the 6 XL blocks, I checked, ranged from .400” to .404”, so .402 was about average.



Thanks for that info, it's very helpful! It sounds like I'll still need to mill down the shank since it sits about .08 off.


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## ericc (May 23, 2019)

I had a similar problem.  The tool could be cut with a file, barely.  But, the cheap Chinese end mill sets just bounced off, and made the mill (a Jet Bridgeport clone) shake horribly.  Probably a combination of mill and tool not being up tot he challenge.  I fabricated a small vertical (or maybe it should be called axial) flycutter with a cobalt bit in it.  Spun it slow and fed it very carefully, and it did the job.  One cut dulled the bit, but I could sharpen quickly on a grinder.  This is really a one time deal, and this is not the pro way to do it, but at least it worked.


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## John TV (May 23, 2019)

I dulled several different cutters then tried a carbide straight "burr" tool. Very small cuts and slow feed but worked great. A mess to clean though with tiny needle like chips. Just an alternative. John, Minnesota 


Sent from my iPhone using Tapatalk


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## pontiac428 (May 23, 2019)

You could always mount the work to a face plate on the lathe and work it that way.  It's similar to using a fly cutter, but you can do it in the lathe with a heavier cutting bit.  Reason I'm mentioning it is a single point can do lot better than an end mill on hard materials using small hobby-grade machines.


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## matthewsx (May 23, 2019)

I did something like this with my belt sander, just took of a little at a time and quenched with water.

Maybe not strictly orthodox but it worked for me.

John


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## mikey (May 23, 2019)

I would do as John York and Will said. Check the tool holder with a file and if it cuts, you can use an end mill to cut it down to size. I've trimmed down 1/2" Seco and Iscar tool holders with a simple HSS Co end mill to get them on centerline. They were hard but not that hard and HSS Co handled them with no issues.


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## chips&more (May 23, 2019)

So what about this one? The shank is 10mm or a tad bigger than 3/8".

https://www.ebay.com/itm/MGEHR1010-...139862?hash=item25db022156:g:F4QAAOSw7PJZZdRl


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## BGHansen (May 23, 2019)

I milled a couple of BXA QC tool holders wider after mistakenly ordering a couple of 3/4" shanked tools.  Used a carbide end mill and got them widened, but it was some tough cutting.

Chips&more idea is the route I'd go.  Instead of trashing an end mill, just buy a tool holder that fits your AXA tool holder.  They are under $20.  The end mill I trashed was a 1/2" carbide Niagra that goes for about $100.  

Bruce


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## Titanium Knurler (May 23, 2019)

Stioc, I recently ran into a similar problem.  I purchased a Dorian knurler that only comes with a one inch square shank.  Even though the Dorian BXA toolholders will accommodate a one inch shank the center of the knurling tool was too high for my PM 1236-T lathe so I took it to a local machine shop and had them grind down the lower edge a bit. TK


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## stioc (May 24, 2019)

chips&more said:


> So what about this one? The shank is 10mm or a tad bigger than 3/8".
> 
> https://www.ebay.com/itm/MGEHR1010-...139862?hash=item25db022156:g:F4QAAOSw7PJZZdRl





BGHansen said:


> I milled a couple of BXA QC tool holders wider after mistakenly ordering a couple of 3/4" shanked tools.  Used a carbide end mill and got them widened, but it was some tough cutting.
> 
> Chips&more idea is the route I'd go.  Instead of trashing an end mill, just buy a tool holder that fits your AXA tool holder.  They are under $20.  The end mill I trashed was a 1/2" carbide Niagra that goes for about $100.
> 
> Bruce



Great idea but I already started milling it down before getting an emergency call from work and that ended the shop time for tonight. I started with my 4 flute cobalt roughing endmill and it jarred the mill pretty good so I lessened the DOC to .025" and then it seemed like it was mostly just rubbing over it rather than cutting through it. Next I got out the flycutter with a left hand indexable lathe bit and that started to actually cut through it but only about .020" at 1000 RPM (I was too lazy to change the belt config) and about 6IPM (since mine's a CNC I don't have manual hand wheels). I think I made two or three passes so I should be close to the height I need.



Titanium Knurler said:


> Stioc, I recently ran into a similar problem.  I purchased a Dorian knurler that only comes with a one inch square shank.  Even though the Dorian BXA toolholders will accommodate a one inch shank the center of the knurling tool was too high for my PM 1236-T lathe so I took it to a local machine shop and had them grind down the lower edge a bit. TK
> View attachment 295179
> 
> 
> ...



Wait but we're the machine shop, are we not?  Good call and that's a nice knurler! I'd be curious to know how you like your 12x36T ? I'm pretty sure that's my next lathe when I have the room and some money put aside for it. Either that or the G4003G.


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## Titanium Knurler (May 24, 2019)

Stioc, you are right, I guess we are supposed to be the machine shop but those damn tool holders are really tough!  I don’t own a surface grinder so I tried an end mill and made no progress, then I ground it down using a hand held grinder, it wasn’t pretty, so I dropped it off at a friend that has a machine shop with a grinder and he finished it off for me.  I had him do a couple. The other is an inexpensive Chinese tool holder with a groove on the bottom that is intended for boring bars.  I use that one to hold my dial indicator. 

I like the 1236-T a lot, I am sure you will too!  I would send you a link to a thread I have going on it here on H-M but not sure how to do it.  I noticed some people put something like,”look here”and it links you to something but I haven’t figured that feature out yet.

Hope emergency call went OK

TK


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## darkzero (May 24, 2019)

Titanium Knurler said:


> I would send you a link to a thread I have going on it here on H-M but not sure how to do it. I noticed some people put something like,”look here”and it links you to something but I haven’t figured that feature out yet.



Some of the BB Code can be found on the Help page here.

4th section down, first example (URL=Link - Linking Advanced)

Or you can use the linking feature in the text editor.


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## stioc (May 24, 2019)

Thanks TK! I think I found your thread:








						Setting-up the PM 1236-T Lathe
					

I have now had my PM 1236-T lathe for about a year now.  I thought I would share my experience with setting-up and using the machine for anyone that is interested.  This is not meant to be a review, but I think at the end you will have a pretty good feel for this lathe.  I will give you the...




					www.hobby-machinist.com
				




I'll be reading it with interest this weekend.


Sent from my Nexus 6P using Tapatalk


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## Titanium Knurler (May 26, 2019)

Stioc, this is what I did with my dial indicator.  I used a cheap tool holder, had a corner ground down and just keep the indicator attached at center height:


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## Titanium Knurler (May 26, 2019)

Sorry about that,  I screwed up posting.  I have been having trouble with our WiFi connection and it didn’t look the photos had loaded so I tried several times, then hit the post button by accident.  Maybe I need another cup of coffee.

Anyway, this works for me, it’s quick and easy but, as you mentioned before, I did have to take it into a shop to have the edge ground.  Is it still cheating if a friend does it for free?

One more shot(I hope):


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