Carbide bits

[Paul Engle]

In response to a fellow turner intrested in carbide bits...the below link ( I am not affiliated with or have any financial dealing with ) has the round carbide insert with a hole in the middle and a screw made to fit the insert, you just match the thread screw with drill / and tap to make you own holder or replace with these. When it gets dull , loosend the screw , magic marker mark the spot , turn a little bit , tighten and away you go. Most mfgrs sell in 10 packs which will give you bits to last a long time...this link is in 5 packs with 3 different sizes available to order . 8 mm,10mm,12mm, just for the woodworker. They do not have a way to answer our questions but have dedicated a page for the round insert. :D If you have any questions PM me.

http://www.carbidedepot.com/wood-turning.htm


Paul

[Mike Minto]

paul, glad you posted this link. i went there, found the cutters to currently be 'on sale' and bought a 5-pack of the 12mm ones. MUCH less expensive than the retail one i bought to make my own tool - have you bought from these guys? looking forward to receiving them and making more tools!

[Chris Stolicky]

I ordered these and the transaction was fine.

The ~$4 screw is an odd size so I had to order a special tap (McMaster Carr).

I can't say if they fit any marketed tool because I made my own shaft. I am almost finished with the handle for it. I did slide it in a generic handle just to try it out and it cut wood! These types of tools have a bit of a learning curve and I have never used any of the other hollowing-type tools to compare it to.

I hope this helps...

[Mike Minto]

chris, why did you use their 'proprietary' screw? won't any off-the-shelf screw that fits thru the hole work? i made my own tool with steel bar and a 'hunter' cutter - used my own screw for that. :confused:

[Dan Forman]

My experience with carbide cutters is that they need a substantially greater relief angle to cut well. The one pictured appears to have a shallow angle, similar to that which is standard for metal cutting, this one is 7 degrees. For woodturning, you want something more like 30 - 35 degrees, like the ones used by the C1 tool folks (EZ Rougher, EZ Finisher).

There is a fellow on the penturners.org website who had some of these cutters made, and sells them for $9, as well as tools to hold them. These had to be special ordered from the manufacturer, as the cutting angle is non-standard for metal cutting.

Sorry I can't provide a direct link to another public forum due to TOS agreement, but you can see a thread about the tool and spare cutters at penturners.org, go to the business classifieds near the bottom of the forum index page, search for "rotondo", you want the thread that is at least 2 pages long. Dig around on the site and you will find a number of threads discussing carbide cutters, proper cutting angles, and such. I bought two of the round cutters, but haven't fashioned a tool holder for them yet, so can't give a first hand account as yet, but there are happy customers on the thread.

I previously bought a tool off Ebay that used a standard round carbide cutter, with the shallow angle, and was not at all impressed. In contrast, I made my own version of the EZ rougher, using a spare carbide cutter (square) from my Byrd Shelix jointer/planer cutting head, which has the greater relief angle, and it works very well.

So, the idea for carbide cutters is great, you just need the proper cutting angle ground into the cutter. Please consider this before you stock up on cutters.

I have no connection to the seller mentioned above, just posting this as a public service.

Dan

[Paul Engle]

If you make or use your own screw , be sure that there is no or very little play between the screw and the bit, and better to find one that has an unthreaded portion the same depth as the bit as it will be less likely to shift, you do no want it shifting around when it is loaded up. For the turners that use the square bit ( the one I do roughing with ) these are also found on their site as well as a host of other companies that make/sell it , same principle but can be shaped and sharpened on your grinder with a silicone carbide grinding wheel. I got some HHS and carbide from LittleMachineshop.com ( no financial intrest) as one can buy just one and try it out before commiting to a 5 or 10 pack.
I like the HHS as I can resharpen it easily, and as some of you know I have converted my 1236 to turn steel/brass/alum/ as well as wood on it ... so these work back and forth and give me good flexability. I have an alum knobed walnut box w/ornamental work on the lid in the finish stages and when it is done I will post it soon.

[Mike Minto]

here are the new carbide cutters, in their '5 pack' container. in the photo of the two individual cutters, one is from hunter, one is from kennametal. can you tell any difference, particularly in bevel angle? i can't. if hunter sells them with this angle, i can't believe another company's cutter with a different angle would do a better job. 'sides, i've used my hunter cutter with (for me) success, making rough turnings into smooth ones. when i so use one of the new ones i just received, i'll post. for this price, it's a deal - wish i had known about them sooner. sorry about the poor photog.

[Dave Rudy]

Mike,

I will look forward to your report. I just received the woodcut (New Zealand) cup hollowing tool, which has a round hss bit (made for carbide replacement in my view!) set at a trailing angle to avoid catches in hollowing. I will try it tomorrow in a captive hollowing rig.

In any case, I am very interested whether the cutters are comparable, because the prices are extremely far apart.

[Mike Minto]

dave, i won't be using one of my new ones for a while (not according to how long these things are supposed to last, anyway :D). but as i say, these new ones appear to be ground at the same 'trailing angle' as the hunter cutters - and i use it with, for me anyway, great success at leaving a smooth surface. when i do use one, in the future, i'll post about it.

[Kyle Iwamoto]

Hmm. Interesting. I have a Hunter, and I also made a rougher clone using the Byrd cutter. I agree with Dan, that the Byrd is more agressive and cuts better due to the relief, BUT, I think it's WAY too "grabby". Since I only have a mini, it stops it no problem, so that's a small problem, IMO. I do like the Hunter, I may have to order those. The Hunter is not as grabby. You folks with the big lathes and sufficient power may prefer the more agressive cutters. Just my $.02.

You can get a 10 pack of Byrd cutters from Griz for 30 bucks.

[Mike Minto]

kyle, you are talking about the square cutters, yes? the ones we were discussing are circular, so i'm not surprised the ones from grizzly are more 'grabby', although the round ones can be with too heavy a hand. kinda apples and oranges, though, to compare the two, i'd think. thanks for the source, however.

[Kyle Iwamoto]

Yes, they are the square replacement cutters for the Byrd shelix head.

[Dan Forman]

I guess I wrongly assumed that the cutters in question were flat on the top like the Easy Finisher tool, rather than cupped, like the Hunter. In that case, my comments won't apply, and you should be in good shape (no pun intended). Sorry for the confusion.

Dan

[Dick Strauss]

I've tried the ones shown with little relief angle on the sides and a small dish on the top surface. They are not aggressive enough for my taste. I've had a hard time taking off more than 1/64" on each pass. They can be used for the final smoothing cut to remove minor ripples though.

I haven't tried the Easy Rougher or Hunter tools so I don't know how they compare.

[Dan Forman]

Dick--- I believe the dished style are supposed to be used as a shear scrape, that is, canted at about a 45 degree angle to the tool rest, rather than presented parallel to the ways. I don't think they were designed for hogging out though, more for finishing cuts. I have very little experience with them however, so hopefully someone else can help you out.

Dan