can solid carbide bits be resharpened?
jerseyjeff
| Posted in Tools for Home Building on
I went out and bought a very expensive (50$) 1/2 shank, 1/2 inch diameter solid carbide upcutting bit to cut some mortises in some pressure treated wood… As I am routing the wood I heard the router change pitch, and felt it torque, I stop the router look in the mortise and discover half of a screw, and then notice that there is a chunk out of the middle of my brand new very expensive bit…. can they be resharpened….
jeff
Replies
yes they certainly can. We had a shop locally that did all of our CNC bits. This was in PA. The chunk out tho' is bad news..that much grinding may weaken the bit..I'd have it touched up, and plan on tossing it..after a few touchups..it may be unsafe NOW without seeeing it I can't tell..
Don't be fuelish if it is unsafe, chuck it and learn.
a broken bit can be a scary thing, and carbide at 22K rpm..a bullet.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
" stop the router look in the mortise and discover half of a screw,"
JR,
Must have been a "Piffin screw"? Decent carbide will usually cut through anything. I've CNC'ed broken cobalt tap's out with C2. Interesting process as the friction heats the cutter to an orange color, and anneals (softens) the tap as it's bored out. In your case,
"can they be re-sharpened"
It's probably not worth it. It will never be the same even if it is resharpened..
BTW, carbide is sharpened with diamonds, NOTHING ELSE, It can be cut, or should I say, chipped away with silicone carbide (green) wheels though.
Jon
They can be resharpened. I even touch up my own with a diamond hone set. However, the chunk out means that this particular bit is a very poor candidate. It is almost certainly not worthwhile to rehsharpen this one. The sharpening would more costly (because of the chip) and the performance of the resharpened bit would not likely be up to par either. It will be cheaper and faster to replace this bit.
and to add one more comment.
Every resharpening, reduces the diameter of the bit slightly..maybe only a change of two or three thoundsanths..but in our CNC work we had to account for bit actual cut diameter.
I Have had great sucess at home shop with standard HSS spiral endmills..from MSC or Mcmaster Carr..often SHARPER than a carbide cutter, and a heck of a lot less expensive. A 3/4" spiral two flute, 1/2'' shank ,3'' long..'bout 10 bucks..tops.
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
"in our CNC work we had to account for bit actual cut diameter."
Sphere,
Different worlds......I take it you were a CNC set-up tech/operator in a wqod mfr environment? I think you may have alluded to that in the past? No?
Right on about the HSS. Can be sharpened way sharper than carbide, but they both have their place.
Jon
yeah Jon, we actually routed out the blanks for solid body guitars. At the same time, we drilled the all the holes for pickups, knobs and neck pockets..bolt on necks.
standard was a single or two flute carbide cutter in the Perske 7.5 HP head, and a 1/4'' Dia. Spiral down cut in the 3HP Bosch head..
The 1/2 cutters were sharpened as needed and the cutting path always included the OA Dia. of the cutter (esp. for the neck pockets.. +/- .002
All work was held with Carter Vacuum pods..and programmed from an old (new then) PC runnin DOS. I recall the tediousness of plotting points from a blueprint, and a LOT of trial an error, it was all new to me , this was in '92-'94.
And yup, HSS is way more economical than carbide.
Brake drums being turned down..trashed almost.
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
I tagged a deckmate screw, I am not sure if that is good enough to qualify as a Piffin screw (I think I get the joke now)
Can I use carbide milling bits in a regular 1/2" dewalt router? I like the idea of 10-15 $ bits instead of destroying another 45 dollar bit!!!
Jeff
you want a HSS not carbide..endmills. Yes, you can use them..provided you get the single end mills, some are flippable (cutting on both ends) which work well in the vert. milling mach. collets, not as well in a router collet..I have used them, but will refrain from advising YOU to.
They also come in a 3/8 SHANK which most router bits do not, even tho' collet adapters are made for most routers. I also use 1/8 shank bits with an adapter. Obviously NOT in a 3Hp. pluge router..but a small laminate trimmer does well with them, think roto-zip..
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
>> ... some are flippable (cutting on both ends) ...
I saw a money saving tip in a machinists magazine. Guy bought double ended end mills and sawed them in half on an abrasive cutoff saw. One double ender costs less than two singles, if you don't count your time or the wear and tear on the saw.
...and ya don't need the shank length. I have chucked them in routers many times, with no apparent damage, just be certain the collet fingers are on the shank vs. the flutes.
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
No thanks. Even unemployed my time is worth too much to spend any of it cutting end mills in half. Not to mention the wear and tear on the saw.
Edited 5/18/2004 7:06 am ET by Uncle Dunc
"Can I use carbide milling bits in a regular 1/2" dewalt router?"
Yes and no. They are designed for use at slower speeds, which means they don't have the same shape as a wood router bit. They are beefier, but prone to burning and chatter at high speed. If your router is variable speed, probably.
Jon
"All work was held with Carter Vacuum pods..and programmed from an old (new then) PC runnin DOS. I recall the tediousness of plotting points from a blueprint, and a LOT of trial an error, it was all new to me , this was in '92-'94."
Sphere,
WOW, people were still doing that then !!! ? At that time we had already made the transition to doing everything with 3D models. Just mouse click on the geometry, and there's your tool path.
Though, I have to admit back then we were running cutting edge UNIX workstations....about $70K each fully configured.
Jon
shucks, our whole CNC was about 30K..not state of the art.
As a matter of fact, the SCMI wide belt sander ( dual belt, with DRO) was MORE than the CNC.
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
"our whole CNC was about 30K..not state of the art."
Sphere,
Guess I'm spoiled. Been working with cutting edge stuff for over ten years. Here are some pics I took a year ago and never got around to posting.
The fiance at the time wanted something personal to give out as wedding "favors", so I CNC'ed up a chocolate bar/mold. Had chocolates made up, rapped in colored foil, and tied with tiny ribbons and tiny wedding bells.
Hardest part was the wedding bells, as they imported in as a spline and needed to be cleaned up. The fonts were just True Types grabbed off the Internet
Normally, we model everything in 3D solids, buy this was for me, so I cheated and just did it all as a wireframe.
Jon
Lower rez pics to follow for you low tech guy's
Edited 5/19/2004 10:12 am ET by WorkshopJon
Resized the big ones.
Jon
Edited 5/19/2004 10:00 am ET by WorkshopJon
Forgot this one,
They can be resharpened. i do it all the time and get better results then when they were new . I got one heck of a good machinist who does it for me.
With that being said he is not a miricle worker. Depending on how bad your bit is damaged and where it may not be possible to salvage.
Darkworksite4:
El americano pasado hacia fuera ase la bandera
very cool..
I need one of those machines here at home, all this hand work is getting tiring..
you ever going back to work?
or finish yer house first?
curious cuz I always have a project or two come up that would be best done CNC, and might throw some things yur way.
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Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
"I need one of those machines here at home, all this hand work is getting tiring.."
Yeah, me too. Luckily I can use anything I want at work for personal stuff. And while those machines are great, they definitely can't replace a good set of hands and eyes.
"you ever going back to work?
or finish yer house first?"
Right now, finishing my house is my work, as well as doing everything a,...um, house husband would do. Things are picking up at work, but right now I'm in no rush to go back, given the weather has turned nice.
"curious cuz I always have a project or two come up that would be best done CNC, and might throw some things yur way."
We specialize more in very high tolerance stuff (+/- 0.0001" to 0.0003"), and are pricey, but I do have a close friend in NY who does do short-run/one-off runs of simple stuff if you ever need.
Our facility is more tailored to aerospace type stuff. We're even ISO 9002 certified now.
Jon
We're even ISO 9002 certified now.
Just what does ISO 9002 certification actually do for a customer? I have seen some cynical comments that it just basically means you can do your reporting paperwork correctly.
"Just what does ISO 9002 certification actually do for a customer? I have seen some cynical comments that it just basically means you can do your reporting paperwork correctly. "
Casey,
Pretty much guarantees a customer that what you say you are giving them, is in fact what you are giving them, and if what you give them isn't, there is a clear data trail (paper or electronic) to easily find what went wrong, and who is to blame.
It does not in any way mandate any "we are the best" level of quality. That's why it is often criticized. You could probably purchase ISO cow manure. On the other hand, the sheer cost to implement, and by it's very nature, it does in fact result in high quality products.
It is as much a marketing tool, as a production tool. Try getting work from NASA or a defense contractor without it nowadays.
Jon