Official Luthiers Forum!

I noticed Bluecreek guitars sells a router that uses an air die grinder. Can anyone tell me if they're any good? I know Bluecreek is well respected but I've seen a lot of cheap air pencil grinders that are a lot cheaper on ebay or whatever, so just wondering if their stuff is a cut above the average?

The stuff looks attractive because of its small size and high RPM... now if I can just fit a circle guide to it to do rosettes...

I've been looking at pencil grinders in Taiwan but they only accept 3mm bits, not 1/8" bits, so they won't really work...

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Question is, are there circle jigs that works with this setup? I think it will be perfect for rosettes. I had a homemade Wells/Karol jig that seems to flex a little bit, enough to make inconsistent rosette channel... that is wider at the bottom than the top!

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I like mine and it works great for detail routing routing tasks and inlay. Don't have a circle jig for it but that's not a bad idea. I use a standard Wells-Karol with a lam trimmer.

_________________
Steve Smith
"Music is what feelings sound like"

So how are the runout on those air pencil grinder? I read the cheap ones have terrible runout, like on the order of .030" or more. I know dremels are terrible because there is a lot of play at the spindle... and the Foredom style grinder I have works well, no runout that I can detect or any plays at all... it's just a shame that the RPM is so low...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

these are very low runout. They are commercial units and are designed to work with metal. If you modify this for a rosette cutter you need to make a new top and use 3 supports for higher accuracy. I also have a higher end unit that uses a Souix brand unit that spins at 70,000 rpm. The dremel is way too much runout , and the foredom is a good unit for those without Compressed air. Thanks for the kind words by the way

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Understood. I saw more expensive ones that uses higher quality bearings in Taiwan but it costs the same as your unit (but without any router base). So it looks like I will definitely be getting this one... I guess for rosette I can still use the laminate trimmer, visibility isn't so critical there but for inlays the lam trimmer seems too heavy especially for delicate work.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

John Hall's unit is excellent for inlay work.

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Steve Smith
"Music is what feelings sound like"

Big fan of Blues Creek here !....I prefer the Sioux die grinder though....and it's worth the extra moohla, in my humble opinion. I use it for inlay work too..actually I should say I only use it for inlay. For Rosettes I use the Dremel 8220-2/28 12-Volt Max Cordless with the stewmac downcut bit....solved the cord twist problem, and the speed is fine for a good job.
Michael

This is a nice one: http://www.use-enco.com/1/1/45571-12r04 ... nders.html

http://www.amazon.com/Pencil-Die-Grinde ... B0001X1YLA
these are the ones I use the most. it spins at 70,000 rpm and uses less air. It is also has a more cylindrical shape and affords itself to work in a machined hole.

http://www.amazon.com/Pencil-Grinder-PE ... pencil+die

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I bought the john hall air die grinder and the stew- mac new circle cutter. I had a machinest reconfigure the circle cutter to cut a perfect circle using the die grinder .He found dead center by using a Large CNC machhine. So now it can be used either way with the stew mac base as a circle cutter or inlay cutter using the john hall air die grinder .

I just wanted to point out a huge pet peeve of mine which takes place on the page you linked. The one star review by someone who didn't realize this was a pneumatic tool and had no idea how to use it. Can't stand it when someone takes the time to write a poor review based on their own mistakes, like writing a bad review of a recipe after you change four of the ingredients. Just doesn't make sense!

By the way is it possible to get metric collet for this thing? I realized in Taiwan they don't always have 1/8" bits.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Just a note on runout and router bits. If your router (or Dremel, Foredom, die grinder) has runout, a straight flute bit will cut a scalloped channel. Multiple passes will even out the scallops.

An up-cut, or down-cut bit in a tool with runout will cut a fascinating assortment of channels--hourglass, barrel shaped, wedge, taper. You'll get a new profile every time you put the bit in.

I only mention this because I felt like an idiot when I finally figured it out.

When you say scalloped, hourglass, barrel profile, do you mean top profile or vertical profile? I find when I cut a rosette channel I get absolutely no deviance with a single pass, but when making multiple passes to cut wider channel I run into problems like the bottom half of the rosette circle being wider than the top... but I think this has more to do with the circle jig flexing than runout. I never have any issue when cutting saddle slots for example because nothing flexes.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

the bits are available and the dremel tool has a collet for the smaller bits. I will see if one if available.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I have a few 3mm collets that looks Dremel type but I was wondering if they are interchangable...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Hi John,

All the documentation I can find on this grinder seem to suggest a cfm requirement of 5.50. On your website you indicate 0.9cfm. Is your model actually the same or is it different? I have a pretty small compressor and it definitely can't pump out 5.5cfm.

Thanks,
Charlton

I can confirm it definitely requires 5CFM or more. It's surprising how much air this little bugger uses. If you have a small compressor get an electric die grinder and have someone make an acrylic router jig.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Evening, all.

Question about runout with dremels:

Is there any way to mitigate this? Would buying higher quality bits aid in reducing wobble or is this how it is always going to be with that tool?

I have John's lower cost version. It runs great on my portable 4.4CFM @ 90PSI Ingersoll Rand compressor.

_________________
Steve Smith
"Music is what feelings sound like"

I heard about putting heat shrink tube around the bearing to improve its runout...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Thanks, Tai Fu. That's too bad. I guess the slower grinder has much more modest air requirements. Maybe I'll get that instead.

Charlton

I see that they did change the air requirement . The souix uses less air. I will change the listing thanks
As for run out , these have very little as compared dremel tools. The die grinder uses a roller bearing and not a bushing.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I thought the 70k one in the link was the Sioux. It's the one that presumably needs 5.5cfm.

Charlton