Help with metalworking skills, or lack thereof.

Martino

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I had three Train Line R7 points. When I purchased a fourth it had a much improved frog area which made electrical conductivity work better. I found i could get new bases and frogs to rebuild the old ones, which I did. I was a happy boy. I (of course I did!) kept the old parts ‘just in case’. Roll on a couple of years and I’ve gone battery power, so electrical worries track wise are no longer an issue. Having got the old point bases, frogs and a heap of rail I’ve decided to create three ‘new’ points. None of that’s a problem (cutting, shaping and filing track is fine) BUT I need to screw the rail to the plastic base and create new tie bars. This means obtaining suitable screws (not insurmountable) however how do I ‘tap’ if that’s the right word, the correct threads into the brass rail?

I did woodwork at school (badly) and never picked up any metalworking skills from my father. I do have some of my father’s taps etc., but they’re all far too big, invariably standards that have long since changed and I’ve no idea how to use them anyway.

I’ll obviously Google the solution but thought that the folks here may have some guidance for a badger like me! Help!
 
Small taps are available from a multitude of suppliers but I would start with Squires Tools. They also sell the small bolts to match.
I think there is a link to them in our 'Links' section on here.
 
Thank you Stockers. Very useful. I’ll probably need to use someone like Micomark here in the US, but that points me in the right direction. I’m very grateful.
 
I had three Train Line R7 points. When I purchased a fourth it had a much improved frog area which made electrical conductivity work better. I found i could get new bases and frogs to rebuild the old ones, which I did. I was a happy boy. I (of course I did!) kept the old parts ‘just in case’. Roll on a couple of years and I’ve gone battery power, so electrical worries track wise are no longer an issue. Having got the old point bases, frogs and a heap of rail I’ve decided to create three ‘new’ points. None of that’s a problem (cutting, shaping and filing track is fine) BUT I need to screw the rail to the plastic base and create new tie bars. This means obtaining suitable screws (not insurmountable) however how do I ‘tap’ if that’s the right word, the correct threads into the brass rail?

I did woodwork at school (badly) and never picked up any metalworking skills from my father. I do have some of my father’s taps etc., but they’re all far too big, invariably standards that have long since changed and I’ve no idea how to use them anyway.

I’ll obviously Google the solution but thought that the folks here may have some guidance for a badger like me! Help!
Another way without using small Taps n Dies which break oh so readily and are a swine to remove. Dont ask how I know this!


Drill through the Webb and into the sleeper. Make a 7 out of some stiff wire just under the size of said hole. Poke it through the hole so that the short part of the 7 is holding the rail then if you have drilled correctly you should be abke to bend the bit that comes through into the gap of the sleeper below. Might be worthwile to put the top of the 7 on the edge of a vice then with a punch tap the bottom bend well down to get a good solid join with the bent 7.
 
Another way without using small Taps n Dies which break oh so readily and are a swine to remove. Dont ask how I know this!


Drill through the Webb and into the sleeper. Make a 7 out of some stiff wire just under the size of said hole. Poke it through the hole so that the short part of the 7 is holding the rail then if you have drilled correctly you should be abke to bend the bit that comes through into the gap of the sleeper below. Might be worthwile to put the top of the 7 on the edge of a vice then with a punch tap the bottom bend well down to get a good solid join with the bent 7.

That sounds an interesting solution Jon. I have no experience using taps of any size, so that could be good for me while I gain some skills! Thank you.
 
You'll find all this online, but the key thing is to buy a taper (1st) tap and a bottom or plug (3rd) tap for the thread you want; and also a 'tapping size' drill -this will drill the hole which the thread will be cut into. And you'll need a tap wrench -I prefer the bar type, but you can also get T-shaped ones -have a google and you'll see what I mean.
Clamp the rail securely in a vice, centre punch it, and then drill the tapping hole -ideally with a pillar drill. Put your taper tap in the tap wrench. Some people recommend a cutting lubricant, but if you are tapping into brass you can use saliva -it is specially formulated to have just the correct properties! Making sure the tap is vertical, turn the tap wrench, applying downwards pressure with your thumbs. Turn the tap half a turn clockwise, then a quarter turn anti-clockwise; this will snap off the tiny curl of swarf you've just created. Continue with a half turn forward, quarter turn back; if you get any resistance (i.e. the tap feels stiff, or jams) go very carefully: taps are hard, and therefore brittle -they snap all too easily. This can also happen when the tap 'bottoms out' in a blind hole -the tip of the tap touches the bottom of the hole. When this happens, unscrew the taper tap from the hole and turn the rail upside down so any swarf falls out. Because the taper tap is tapered, the full thread isn't formed until the 7th thread enters the rail; so you now need to put the plug tap in the wrench and repeat the process -half a turn clockwise, a quarter turn back, until the plug tap bottoms out. Unscrew it from the hole, tip out any swarf, and try fitting a screw into the hole.

It is probably worth practicing on a scrap piece of brass -and buy some spare taps, as you will break some, particularly at the size you are going to need. Experience doesn't stop you breaking taps -it just happens less often!
 
You'll find all this online, but the key thing is to buy a taper (1st) tap and a bottom or plug (3rd) tap for the thread you want; and also a 'tapping size' drill -this will drill the hole which the thread will be cut into. And you'll need a tap wrench -I prefer the bar type, but you can also get T-shaped ones -have a google and you'll see what I mean.
Clamp the rail securely in a vice, centre punch it, and then drill the tapping hole -ideally with a pillar drill. Put your taper tap in the tap wrench. Some people recommend a cutting lubricant, but if you are tapping into brass you can use saliva -it is specially formulated to have just the correct properties! Making sure the tap is vertical, turn the tap wrench, applying downwards pressure with your thumbs. Turn the tap half a turn clockwise, then a quarter turn anti-clockwise; this will snap off the tiny curl of swarf you've just created. Continue with a half turn forward, quarter turn back; if you get any resistance (i.e. the tap feels stiff, or jams) go very carefully: taps are hard, and therefore brittle -they snap all too easily. This can also happen when the tap 'bottoms out' in a blind hole -the tip of the tap touches the bottom of the hole. When this happens, unscrew the taper tap from the hole and turn the rail upside down so any swarf falls out. Because the taper tap is tapered, the full thread isn't formed until the 7th thread enters the rail; so you now need to put the plug tap in the wrench and repeat the process -half a turn clockwise, a quarter turn back, until the plug tap bottoms out. Unscrew it from the hole, tip out any swarf, and try fitting a screw into the hole.

It is probably worth practicing on a scrap piece of brass -and buy some spare taps, as you will break some, particularly at the size you are going to need. Experience doesn't stop you breaking taps -it just happens less often!
Thank you very much. A great description. I’m sure I’m going to need lots of practice - and taps!
 
Wouldn't using small self-tapping screws work?
That’s not a bad idea at all! .....unless anyone knows otherwise.
 
That’s not a bad idea at all! .....unless anyone knows otherwise.

I use 2mm Stainless Steel self tappers - but I drill 'down' through the foot of the rail. I take it you want to drill centrally 'up' into the rail web - as per Aristocraft? I use a 2mm drill bit for the screws and that method might not work if you totally want to conceal the fixings ( unless you are drilling into the foot and screwing in from underneath).
 
That’s not a bad idea at all! .....unless anyone knows otherwise.
Not sure how small you can get self tappers and in my experience they are a devil to file so grinding would be the method if you go from the bottom. Then you would need to use a small Model Makers Grinding wheel if you have them. Self Tappers from the top may cause Flanges to bump on the heads on the inside rail. Plus you will need rather a lot.
 
Shouldn't be too tricky a job to drill if you have the right tools?

I have repaired an LGB R3 point for a GSC member, by drilling and tapping.

Use a pillar drill if possible so everything stays square and perpendicular.

When tapping brass rail, use a little 3 in 1 type lubricant.

As mentioned by Northsider, use a Taper first, and a Plug last.

Each time tap half a turn, then back off a quarter turn, then repeat, so that you cut your thread a little at a time.

Good luck Martin....
 
Thank you Gentlemen. I’m very grateful for the advice and support.
 
I use 2mm Stainless Steel self tappers - but I drill 'down' through the foot of the rail. I take it you want to drill centrally 'up' into the rail web - as per Aristocraft? I use a 2mm drill bit for the screws and that method might not work if you totally want to conceal the fixings ( unless you are drilling into the foot and screwing in from underneath).
Yes, that’s the idea. I’m coming up from the underside of the plastic point web and into the base of the rail. In theory it’s not going to show. The ideal way would be to drill and tap of course. ...and I may need to to acquire that skill.
 
Yes, that’s the idea. I’m coming up from the underside of the plastic point web and into the base of the rail. In theory it’s not going to show. The ideal way would be to drill and tap of course. ...and I may need to to acquire that skill.
Try both ways and see what suits you best. As for practising, no one is born with skills, so practice makes perfect, and take your time
 
20180128_125016.jpg 20180128_124956.jpg I use 3/8 in stainless steel dog spikes from micromart which holds the rail in a prototypical manner. I find it much easier to make small adustments to gauge if needed
Tim
 
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You'll find all this online, but the key thing is to buy a taper (1st) tap and a bottom or plug (3rd) tap for the thread you want; and also a 'tapping size' drill -this will drill the hole which the thread will be cut into. And you'll need a tap wrench -I prefer the bar type, but you can also get T-shaped ones -have a google and you'll see what I mean.
Clamp the rail securely in a vice, centre punch it, and then drill the tapping hole -ideally with a pillar drill. Put your taper tap in the tap wrench. Some people recommend a cutting lubricant, but if you are tapping into brass you can use saliva -it is specially formulated to have just the correct properties! Making sure the tap is vertical, turn the tap wrench, applying downwards pressure with your thumbs. Turn the tap half a turn clockwise, then a quarter turn anti-clockwise; this will snap off the tiny curl of swarf you've just created. Continue with a half turn forward, quarter turn back; if you get any resistance (i.e. the tap feels stiff, or jams) go very carefully: taps are hard, and therefore brittle -they snap all too easily. This can also happen when the tap 'bottoms out' in a blind hole -the tip of the tap touches the bottom of the hole. When this happens, unscrew the taper tap from the hole and turn the rail upside down so any swarf falls out. Because the taper tap is tapered, the full thread isn't formed until the 7th thread enters the rail; so you now need to put the plug tap in the wrench and repeat the process -half a turn clockwise, a quarter turn back, until the plug tap bottoms out. Unscrew it from the hole, tip out any swarf, and try fitting a screw into the hole.
While all this is very sound advice, it is quite difficult for a novice or someone without machine shop training to implement. (Ask me how I know.)
It is very difficult to hold the tap vertically and to turn it on the average workbench. I usually find that the size of the T holder means a little too much pressure on one side and 'snap' there goes another tap. A small drill holder, like this one, I find is easier to manage and keep it vertical.

http://thumbs4.ebaystatic.com/d/l225/m/m_EebQHPkOyJHPs2CRmYF4g.jpg
m_EebQHPkOyJHPs2CRmYF4g.jpg


NWSL here in the US makes a small tap stand that is like a vertical drill press but just holds the tap and lets you concentrate on the delicacy of the turning. I think it's called a Sensi-Press. Note it doesn't have a big T handle, which I think was invented for much bigger taps that weren't so easy to break.

476a7241d55e6cdf4f1c51d252a564dc--drills.jpg


Yes, you absolutely need a proper sized tap drill and a tap clearance drill - as mentioned they make the hole for the tap and the clearance drill is the size to clear the bolt after you have inserted it in the thread.
 
While all this is very sound advice, it is quite difficult for a novice or someone without machine shop training to implement. (Ask me how I know.)
It is very difficult to hold the tap vertically and to turn it on the average workbench. I usually find that the size of the T holder means a little too much pressure on one side and 'snap' there goes another tap. A small drill holder, like this one, I find is easier to manage and keep it vertical.

http://thumbs4.ebaystatic.com/d/l225/m/m_EebQHPkOyJHPs2CRmYF4g.jpg
m_EebQHPkOyJHPs2CRmYF4g.jpg


NWSL here in the US makes a small tap stand that is like a vertical drill press but just holds the tap and lets you concentrate on the delicacy of the turning. I think it's called a Sensi-Press. Note it doesn't have a big T handle, which I think was invented for much bigger taps that weren't so easy to break.

476a7241d55e6cdf4f1c51d252a564dc--drills.jpg


Yes, you absolutely need a proper sized tap drill and a tap clearance drill - as mentioned they make the hole for the tap and the clearance drill is the size to clear the bolt after you have inserted it in the thread.
That looks a nifty bit of kit. I assume you can use it for all sorts of small drilling requirements.
 
That looks a nifty bit of kit. I assume you can use it for all sorts of small drilling requirements.
Paul, I assume you mean the Sensi-Press, as I'm sure you Brits have plenty of small drill holders (called Pin Vises over here.)
It does look useful, but I haven't bothered to get one - probably because I don't tap small holes very often. I find my Dremel in a drill stand handles the small drilling chores.
 
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