Drilling/Tapping Frame Halves

[Steveruger45]

Here is a link on cutting fluids and oils, in case anyone interested.
https://shieldoils.com/cutting-fluid-definition-purpose-properties-types-applications-and-selection/

FWIW and as I said in earlier post I don’t use any when hand tapping loco frames as hand tapping doesn’t generate a lot of heat and the frame material is relatively soft.
I find it more of a nuisance than a help actually, especially in blind tapped holes.

[peteski]

I mainly use the cutting fluid so the soft metal does not stick to the tap.  I also use it for machining operations on my lathe and mill.

[Dwight in Toronto]

Hey Pete, thanks for going to the trouble of snapping a few pics and composing a detailed explanation.  Very helpful.  Indeed, kudos to everyone - good info just keeps trickling in. 

I’m actually more nervous about drilling the pilot hole than doing the tapping.  Seems to me that the poor drill bit has the harder go of it, what with being a smaller diameter, having more material to remove, and being forced to penetrate virgin territory!  I hope to do a trial drill-&-tap within the next week or so; will report back.

[Dwight in Toronto]

Just studied Steve’s link on cutting fluids.  When I bought the wee tap & drill from my hobby shop the other day, I was chatting with one of the fellows there who had done quite a bit of tapping.  He mentioned kerosene as his preferred cutting fluid, and it was interesting to see in the writeup that kerosene is recommended for use with aluminum, so seems to be some validity there.

[Steveruger45]

Dwight,
Yes, kerosene does work pretty well on softer metals as a cutting oil.
I used to use it in the Merchant Marine many decades ago, long before “environmentally safe” and “safety culture” were even invented or part of the lexicon. It never burst into flames on me but
Of course, it has a few obvious safety and health issues to be considered.   

[peteski]

Hey Pete, thanks for going to the trouble of snapping a few pics and composing a detailed explanation.  Very helpful.  Indeed, kudos to everyone - good info just keeps trickling in. 

I’m actually more nervous about drilling the pilot hole than doing the tapping.  Seems to me that the poor drill bit has the harder go of it, what with being a smaller diameter, having more material to remove, and being forced to penetrate virgin territory!  I hope to do a trial drill-&-tap within the next week or so; will report back.

For drill bits I prefer to use the (Tungsten Carbide) PC Board bits with 1/8" shanks. They are super sharp, and have split points so they don't wonder around.  They drill into pot metal like through butter. But those bits are brittle, and while I often use them for hand-held-drilling, for  the type of task that you describe I would use a drill press with the chassis being held securely in a machinist's vise.  But for you good quality (properly sharpened) High Speed Steel bits should work quite well, and at the size used for 00-90 holes, the are fairly sturdy.  If you have some cheap Chinese drill bits, they are probably not sharpened very well.

[Maletrain]

"Cutting fluids"are designed to serve more than one purpose - cooling as well as lubrication/anti-galling. When machines are doing the cutting (drilling, turning, tapping), they do it much faster than by hand, and that builds-up heat.  So, a lot of cutting fluids like Tap Magic are designed to evaporate to cool the part being cut.  But, there is also the "stickiness" of the metal being cut - it can cling to the tool and gall the finish on the part being cut.  Sticking cuttings can even jam the tap in the part.  For hand tapping, that is the important issue.  I usually just use oil for tapping steel, brass and aluminum.  I don't lube to tap plastic.  I had not thought about bee's wax, but that seems less messy.  Can you just stick some in the hole and tap into it? Does it force chips out?

[mmagliaro]

I use a hand held pin vise to drill the pilot hole, and to do the tapping.
Dremel - NO NO NO.  Dremels don't have nearly precise enough bearings or motion to do this without making a sloppy hole and/or
a broken tap.

I use oil - whatever I have handy, 3-in-1, some Labelle, anything so that the hole isn't dry and the tap doesn't get stuck, which is
when they break.   
--
Definitely stay away from cheap carbon steel taps and the $5-$10 cheap ones you'll see on eBay from China. 
The ones Woodland Scenics sells do work, but I'm not a fan of them for tapping into loco frames, as they just don't cut deeply or sharply enough.   A good tap in this size costs some bucks (like 20 or 30 bucks).
In addition to the gun tap already suggested (which would work well), I also like these:
https://minitaps.com/taps-inch-ansi-astm/00-90-taps/00-90-plug-tap-2-flute-hss-21054/
Yeah, like I said, not cheap.
--
I like 3-flute taps because I think they help guide me in a straighter line, especially at the start of the hole, but that's just a personal
preference.  I'd go with plug taps because they have a taper on the front, which is important for getting your hole started (same idea as the spiral taps).

[Dwight in Toronto]

Thanks guys - another bunch of super helpful posts since my last reply. 

It’s obvious that the most experienced opinions are stressing the importance of “not cheaping out” on the drills and taps.  As mentioned near the outset, in my enthusiasm I had already run out to my LHS and grabbed what they had …. small Walthers packets off the rotatable display tree. 

So, I’m sure that what I’ve got are two #65 drill bits and a 00-90 tap from China. Oh well, it’s enough to at least enable me to have a careful, preliminary go at it - a noob start with a low outlay cost.  Wish me luck!

[Dwight in Toronto]

Well, finally got around to drilling and tapping those frame halves.  I’m relieved to say that it was indeed a success.  I was surprised at how much down force had to be exerted at times in order to feel that “gummy bite” sensation that indicates when you’ve made yet another miniscule advancement in the cut.  Definitely a procedure that requires a learned “seat of the pants feel”.   Luckily, no drills nor taps were harmed in any way during this operation!

I have hereby tried to attach a pic, so if that was successful folks will see that my problem now is that the 3/16” 00-90 screws are too long for this particular location.  I suppose I’ve got nothing to lose if I try to snip them a bit shorter, but trying to restore the leading threads seems nigh impossible. 

By the way, this is an Athearn F59PHI frame in which I intend to install an ESU Lok5 Nano.  My plan is to solder the black & red decoder wires to those tiny washers, and thereby pick up track power from the respective frame halves.

Thanks to everyone for giving me the low-down and the confidence to learn this new skill - much appreciated!

[Dwight in Toronto]

Ok, I tried the “Attachments and other options” to attach the pic, but it came up as a thumbnail or something, and rotated 90 degrees.  Same troubles I’ve had before.  Apologies, guys, for my ineptitude. 

I see that there is also an “Add image to post and upload to gallery”, so I’m hereby trying that.  If it still doesn’t work, then I give up - I’ll stick to tapping frames!

[Dwight in Toronto]

Argh … still sideways, but properly sized!  I’m sure someone will educate me on posting pics!

[Jim Starbuck]

I have hereby tried to attach a pic, so if that was successful folks will see that my problem now is that the 3/16” 00-90 screws are too long for this particular location.  I suppose I’ve got nothing to lose if I try to snip them a bit shorter, but trying to restore the leading threads seems nigh impossible. 

Dwight,

Great job on diving in to the drilling and tapping.
Here’s how I shorten my 00-90 brass screws:
I have a piece of sheet copper about 1/16” thick ( brass will work just fine too, I just happen to have the copper laying on the bench) with a hole drilled and tapped for the 00-90.
Run the screw in to the desired length then clip it flush with nippers or a Dremel cut off wheel. After the cut , I use a small flat file and file the cut end flush with the strip surface.
When you back the screw out it chases the treads leaving a clean end.

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Hope this helps,
Jim

[Dwight in Toronto]

Dwight,

Great job on diving in to the drilling and tapping.
Here’s how I shorten my 00-90 brass screws:
I have a piece of sheet copper about 1/16” thick ( brass will work just fine too, I just happen to have the copper laying on the bench) with a hole drilled and tapped for the 00-90.
Run the screw in to the desired length then clip it flush with nippers or a Dremel cut off wheel. After the cut , I use a small flat file and file the cut end flush with the strip surface.
When you back the screw out it chases the treads leaving a clean end.

Jim … I tried your technique, using a piece of 1/16” aluminum, and it worked like a charm!
Thank you so much for the help.

Dwight

[peteski]

Argh … still sideways, but properly sized!  I’m sure someone will educate me on posting pics!

Not sure why you got an upvote on the above post, but here it goes:
Educating: Go to the FAQ section ( https://www.therailwire.net/forum/index.php?board=41.0 ) and you will find answers in the 1st and 3rd sticky threads.

I god a bit wordy in the thread about posting photos. It sounds scary difficult where it really isn't. I might rewrite that info someday.  I do highly recommend uploading photos to your own gallery and organizing them.  That will come in handy when you try to find some photos later. I quite often end up reusing photos I uploaded for one post, in another post.  If you're curious, check out peteski's gallery: https://www.therailwire.net/forum/index.php?action=gallery;su=user;u=2700

When you just upload them the gallery through  the post you're composing (like you just did earlier), unless you first set up a basic gallery structure, those photos will go into a "bucket" where they will be difficult to organize later.  If you create the gallery structure and then upload photos (another nice feature of the gallery is bulk upload) then you can use the photo link from the gallery to paste it into your post (and use "preview" button to see how your post will show up on the forum without wondering if the photos show up properly).