Replies

1. 
   cowtown | Feb 10, 2005 08:56am | #1

   a very small company you say...

   well, to start with, I'd go with lower end HSS bits, 1/2" is cheap enuf, but if they are imported youwill find that prudent sharpening is advisable, cause the low end stuff is generally duller than yer worst kitchen knife. Yer gonna need a fine file to sharpen em.

   They will last you enuf time to get you thinking about whether they suit yer needs, and you won't go broke buying them.

   As for that jig, well, it's not a production jig at all, just a cobbled up device suitable for a hobbiest. Too much fiddling and tightening of nuts. Drill a hole slightly smaller than yer ball in a piece of 2" wood but not all the way through, cover the top of the wood with some 1/4" self adhesive foam , and cut an opening in the top of the holeabout 3/8" smaller in diameter than the hole .

   Then get yerself to an automotive supply house and find a venturi nozzle for a compressor (commonly used for sucking up cleaning solvents with an air hose), drill a hole into the base of yer block of wood and tap it for an air fitting. Use the venturi to draw a vacuum and use yer compressor to power the venturi. Youll find the suction draws the ball down and effectively stabilizes it, and no nuts to undo. You got yerself a cobbled up vacuum vice now and productivity will follow.

   Eric
   in Cowtown

1. 
   brimack11 | Feb 10, 2005 05:12pm | #3

   Hi Eric--

   Thanks for your response.

   I've gotten burned so many times by buying the cheap version of a tool only to have to upgrade it 6 months later.  If cost wasn't the biggest issue in deciding which bits to buy, would you still go with HSS?

   Your jig is amazing.  There is no substitute for the advice of someone with experience.  I'm gonna try to build it ASAP.

   Thanks again--

   Brian

1. 
   cowtown | Feb 12, 2005 04:28am | #7

   I have TC brad point drill bits for my Euro shelf-boring jig 5mm and 1/4" I guess they would cost around 20-22 us$. I generally break one or the other at least once a year, often directly attributable to encountering a brad. They are drilling into Melamine most of the time, so the TC keeps em sharp. With particle board, it's unlikely HSS would stay sharp enuf. The breakage on my small bits is likely because they are so small, and there's no fillet where the TC is soldered to the shank, so any shock is more likely to cause a fracture to occur.My European hinge boring bits are all TC, the only way to go, cause they see a lot of melamine, arborite boring. My first one was HSS, and it dulled way too quickly. Of course with these, there is more physical material to handle load/shock etc. A HSS forstner bit you can sharpen yerself, a carbide one you aren't likely able to. the cost between HSS and carbide for one drill bit hopefully won't break the bank so Ill leave it at that. Eric

2. 
   brimack11 | Feb 17, 2005 10:01pm | #8

   Hi Eric--

   I've spent the last 2 days trying to find a "venturi" nozzle.  I've tried Pep Boys, Advance Auto Parts, Sears and Home Depot.  Most of the people I speak to have never heard of a venturi nozzle.  After telling them what I want to do with it, they don't have it.  Does it go by another name?  I can't even find one online.  Can you recommend a store, even an online store, that might carry it?

   Thanks for your help,

   Brian

1. 
   RickL | Feb 17, 2005 10:27pm | #9

   http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=3952

   Piece of cake!

2. 
   cowtown | Feb 18, 2005 08:17am | #10

   they may not know what they are .....If you tell em you wanna used compressed air to suck up a soap solution and spray it , they will find one quick enuf, or at least get the idea.. I noticed that Lee Valley is selling a vacuum press (#55k6720) that has a hand pump for drawing the vacuum. More money though.Eric

3. 
   RonT | Apr 04, 2007 03:12pm | #13

   Stinky

   I may be a little late; I just stumbled on your string. You won't find what your looking for at the stores you mentioned.

   Go to mcmaster.com and search Jet Pumps. I'd give you a part number, but I don't know what size you need. The smallet available will do the job for you, I think. They show the item used to move liquid, but it will do air as well.

   A jet pumps creates a vacuum using compressed air. You'll need a ball valve between the pump and your work,(vacuum point). It will take seconds to get the vacuum you need and then isolate the vacuum by shutting off the valve then turn off the air. To release, open the valve only.

   This is a good system that can be used for several hold down applications.

   Good luck.

2. 
   cicero | Feb 10, 2005 10:20am | #2

   Get good hss for best edge.I tend to buy these sorts of tools from my tool grinding outfits,you are assured of good quality because they are the ones who are going to sharpen and would be at the best place to complain.

   Tungsten best for production work on MDF and the like.

1. 
   brimack11 | Feb 10, 2005 05:14pm | #4

   Hi--

   Thanks for your response.

   I've gotten burned so many times by buying the cheap version of a tool only to have to upgrade it 6 months later.  If cost wasn't the biggest issue in deciding which bits to buy, would you still go with HSS?  Would you go with Tungsten?

   I'm gonna have to look into a tool grinding outfit in my area.

   Thanks again--

   Brian

1. 
   cicero | Feb 10, 2005 09:41pm | #6

   You will get plenty of opinions on the merits of any tool,which is right?

   The grinder shop deal with sort of thing all day,make sure you talk to the right person in there.

    

3. 
   RickL | Feb 10, 2005 05:45pm | #5

   I recommend the saw tooth forstner bits from Lee Valley. Imported and very inexpensive but just as good as bits I was paying 6 times more for. HSS is better than carbon steel. I buy from all kinds of vendors such as Forrest City, Morris Wood Tool, WL Fuller. I buy some stuff from my sharpening guy but he doesn't always have the best deals or specialty things.

   Centering the jig is easy if you drill partially into the base to register your drill. That jig could be made more production oriented by hinging one side with an air cylinder or toggle clamp on the other side. The idea of a vacuum is a good one. Looking in metal working clamping books yields a lot of interesting possibilities as well. I get a lot of industrial magazines on many subjects where I get lots of great ideas on seemingly unrelated topics to brainstorm unusual solutions.

   
   

   ---

   Edited 2/10/2005 2:59 pm ET by rick3ddd

4. 
   mike4244 | Feb 22, 2005 02:59am | #11

   I have a chinese set set from Grizzly that works fine. You can buy sets of 16 from as low as $40.00 to $500.00. The $40.00 set works fine for me.

   I have not tried to  drill round balls but I think I have the solution. Bore a 2 1/2" hole in a 2x6x 12"long. Rip down the 12" length. Attach a small hinge at one end of the 2x6. Place ball in hole and clamp other end. The sawcut makes the hole a bit smaller. the clamp at the end will hold the ball. The hinge is used instead of another clamp, also holds the two pieces together . This is easier than trying to clamp both ends. Clamp your 2x6 jig to the work surface and drill at 650 rpms.

   This should work, mike

5. 
   MichaelPB | Jul 26, 2005 08:09am | #12

   Brian,

   As someone who does small production runs using a number of drill presses and most of the bits I use are forstner, I have a bit of experience in this.

   The idea for the vacuum jig is perfect, one additional thought though, glue on a disk that is a tight fit on the center hole of your drill press and do all your drilling of both jigs in the machine.  As long as you leave the table alone, they will be centered even if you swap them out.

   The cheap forstner bits are great if you don't expect much from them.  I have a big set that I use for prototyping but if I am going to use one a lot, I ante up the money and buy a high end US or German made one.  The difference in the quality of the cut is amazing.

   Before you let some yokel sharpen your good ones, see what they do to a cheap one first.  I now sharpen them myself after trying the local shops.  They do a fine job on sawblades but butcher things like forstners.

   For a 1/2 hole, I wouldn't use a forsnter, I would use a brad point drill.  You can shallow out the cutting lips and get a fairly flat bottom hole.  Fuller makes some of the best ones, they cut MUCH faster easier.