Where do I find decent index drill bits!!!


iomalley

iomalley

Barely-employed Brakeman
Lately I've been at a loss to find decent index drill bits, especially #80, 79, & 78! The quality has been terrible, some won't push thru the softest resin or plastic, and the odd bulk one from my LHS actually bends 90 deg!!! :mad:

When I used to visit Guil Mack from Tiger Valley models his showed me #80 bits that he used in a drill press to cut thru the battleship metal of his models! :eek:

Anybody have a brand they like and trust? Mascot sucks, it's what's readily available around here, as well as Chinese brands I get from the craft (read:dollar) store....:rolleyes:

help is appreciated
 
I like Walthers drill bits. They seem to work well for me. But then again im not using power equipment when drilling the small holes.... This may be your problem, I would suggest using a pin vise for the small holes of #75-80....
 
BTW, whatever you do, dont get the 10 packs of the small #75-80 drill bits that Model-Expo has, they are horrible and break very easily. They come in a little red tube and this is a case of "you really do get what you pay for." The larger size ones are okay that they have, but man its like as soon as you touch the smaller ones to a model they snap!
 
I'm not using a drill press, I was eluding that I've seen Guil at TV models drill into pewter with #80s!! I just use a hand held pin vise.

I will try walthers and micro-mark. I've never had any trouble with sizes 75 and down in any sets I've gotten, but #80 and #79 are busy bits on my projects...

I hate when the smaller ones bend, that tells me that the manufacturer didn't care to temper them, and was intensionally trying to screw the buyer! bits should always break, never bend.
 
I have the Micromark set also and, although it's better quality than most, those tiny drill bits seem to break no matter what you do. There's another thread wher BNTorsney found a place that sells the small bits for $2.99 for 10. I don't know what the quality is like compared to Model-Expo but I always buy 30 bits if I'm working on projects and assume I'll lose half of them before it's done. I'm not sure you can make really strong, tempered bits in the #75 to #80 range at an affordable price, so I just assume they are expendable.
 
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UP2CSX said:
There's another thread wher BTTorsney found a place that sells the small bits for $2.99 for 10. I don't know what the quality is like compared to Model-Expo
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I think thats what I paid for the pack of 10 as well from Model-Expo lol
 
A tip for my fellow penny-pinchers out there:

If you are cursed with a bunch of “soft” drill bits, you can harden them quite easily. It may not give you the equivalent of the more expensive bits, but it will help those cheaper bit last longer. However they will be more brittle so be forewarned.

Take an unused bit and press it tail-first into a block of wood. Heat it with a propane torch until it glows slightly orange. Concentrate on the tip area for best results, there is no point in hardening the tail end, besides it is stuck in the wood and you need to avoid burning the wood…...

Once it gets to a moderate orange color, quickly dunk the bit in some old oil; heavier like 30wt will tend to work better. It will smoke and sizzle and MAY CATCH FIRE, so obviously you aren’t using more than a thimble-full of oil and you are outside. Fire won’t hurt the bit at all but it may hurt other things. Like you. So be careful.
 
iomalley said:
...and the odd bulk one from my LHS actually bends 90 deg!!! :mad:


help is appreciated
Click to expand...

Bending drills is a sign that the drill isn't loaded far enough into the pin vise. With these smaller drills, you need to load them to where only a short distance more than the depth of the hole you need to drill is sticking out of the end. When I'm using the smaller sizes of drills, I will load them at least 3/4 of the drill length stuck up into the pin vise.

Bending drills are also a sign of too much pressure on the drill. Lay off the pressure, don't push as hard in other words, and keep the drill vertical. By inserting the drill deeper into the pin vise, plus using very little pressure, you won't bend or break near as many as in the past.
 
the fact that it bent 90 degrees in the first place is the sign of a problem. there is no reason why you can't insert the bit so that only 1/4" or even less is sticking out of the pin vise chuck. Most pin vise chucks are made to allow this.
 
Dont force the drill bit through the hole your drilling. Let the drill bit do the work making the hole. You will break a lot less bits this way.
 
You could also use a lubricant of some sort, to help the cutting edge slide more easily across the cut surface and to help left the cut chips away from the hole. I've had some luck with both 3-in-1 Oil and good ol' WD-40.

However, I don't think I'd use oil on a non-metallic surface. I would imagine you could use water on plastics -- but I've not done that myself.

One note -- I've never tried to use a Dremel or somesuch with such small bits -- only a pin vise. And through experience, I've learned that I have to keep my hand as steady as possible -- not wavering from side to side -- and to use very light pressure and let the bit do the work.

Hope this helps!

Regards,
Tom Stockton
 
tomstockton said:
You could also use a lubricant of some sort, to help the cutting edge slide more easily across the cut surface and to help left the cut chips away from the hole. I've had some luck with both 3-in-1 Oil and good ol' WD-40.

However, I don't think I'd use oil on a non-metallic surface. I would imagine you could use water on plastics -- but I've not done that myself.

One note -- I've never tried to use a Dremel or somesuch with such small bits -- only a pin vise. And through experience, I've learned that I have to keep my hand as steady as possible -- not wavering from side to side -- and to use very light pressure and let the bit do the work.

Hope this helps!

Regards,
Tom Stockton
Click to expand...

I heard on a recent Model Railcast that Greg Bisguire(sp) uses a drill bit and an electric screwdriver with those 1/4 in. interchangable bits that you can get everywhere. Micro Mark sells a chuck that you can put a drill bit in and it fits right into the screwdriver. Now you end up with a low RPM hand drill and you can control the bit easier and more straight and he claimed, he hadnt broken a single bit by doing this. Might be worth the try.
 
Chris,

That really sounds like a good idea -- and I "need" a new electric screwdriver since my old one went belly-up about three months ago...

Now... how would one go about mounting one into a drill press-like mounting, so that the movements would be straight and true, with no side-to-side wobble introduced by operator error?... Or would the loss of the "feel" of a pin vise make it easier to try to force the drill bit, and (most likely) break it?

Just thinkin' a little before the caffeine reaches my not-quite-awake brain...

Regards,
Tom
 
I'm afraid this thread has become somewhat ambiguous.

Those of you familiar with Tiger Valley models (Cary or Hobbytown for that matter) know that the bodies are cast in Pewter/white metal. Guil Mack from TV models used to pre-drill #80 holes in his carbodies for grab irons and such.

Does anyone know where to find bits that will do this, in a motorized drill press or in a hand held pin-vise.

I don't want to know the proper technique for how to hold, a pin-vise, or set a drill press rpm....most of the bits that we in the hobby are subjected to are garbage, irregardless of how far 'in' the bit is set in my pin-vise.

If any one knows of jeweller quality bits, #80, 79 or 78, that will gladly charge thru pewter, please let me know...

For the record, I will try the higher quality MM bits.
 
If you could find a good tool & die maker supply house, that's where you are going to find the hardened drill bits that everyone needs. Carbide drill bits are about the best. They are expensive, but, they do last a long time. A glass cutting bit is strong too.
There's just so many places to look, sometimes we don't think outside the box.
 
The best I've ever used are/were manufactured by Continental Drill Corporation. A close second are those manufactured by Avildsen Tools & Machines, Inc. I am down to the last #79 out of a 12 pack, but considering I do a lot of scratchbuilding I'd say they're the real deal. The one I just replaced was broken by my six year old, and it had been used as my current #79 since before she was born. I have been using this particular 12 pack for 19 years and it was purchased by my Grandfather sometime in the late 50s/early 60s. Whether you'll be able to find these or not, I can't say. But whatever you buy, do not go cheap.

I know you don't want to be lectured on technique, but a 90° bend is a red flag. Either the drills you're using are complete trash, or you're doing something wrong, or possibly a combination of both. Even when drilling pewter or brass, you should not apply pressure more than the equivalent of a few grams. The weight of the pin vise should supply sufficient downward force.

Another thing I would advise is to lubricate your bit. I use ordinary candle wax. I also keep the flutes clean, which means backing the drill out frequently, but you'll avoid the majority of opportunities for breakage between lubrication and clean flutes.

Sometimes you can't do anything about hard spots in pewter, other than exercise a great deal of patience, but brute force/high speed with wire gauge drills just creates problems, including safety hazards (keep those eyes protected!).

I agree with Larry, that you should look for a machine shop's recommendation or find a reputable machine supplier. The drills you'll get from hobby suppliers, even the more expensive ones, are probably all made in China garbage.
 
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