How to use blade filing jig?

[jon price]

I did a search but couldn't find this, so, has anyone ever posted photos or video to explain how to use the society produced blade filing jig? If not, would anybody like to as I am completely mistified.

[Derek]

Hello Jon

I found this thread quite useful:
viewtopic.php?f=5&t=1914

Scroll down to the post by Martin Wynne. It has useful diagrams that may help.That's for the crossing vee.

For the blade filing, although he does it manually rather than with a jig, I would recommend:
http://www.norgrove.me.uk/points.html
It shows what you are trying to achieve.


From your post, I am assuming that you are not completely familiar with how prototype turnouts are constructed. If that's the case then you might find it useful to look at:
http://www.templot.com/martweb/gs_realtrack.htm

BTW what templates are you using for construction? Be aware that many of them in circulation have errors of one sort or another. If you haven't already tried it, I can recommend Templot at the above website- (it is a track design programme that is capable of drawing a single highly accurate turnout or replicating Clapham Junction- can be challenging at first, but well worth it).

(the above is the opinions of a beginner who has only recently asked similar questions. Other opinions are available and the author of this post cannot be held accountable if you become addicted to finding 2,001 ways to NOT make a turnout work properly).

[jon price]

Thanks for this. I think I'm OK with the general issues of construction, but I cant work out how to use the jig. The only way I can see it operating is to grip the blade longitudinally, file one half, then place in the other side and file the other half. This doesnt seem eight as it seems to complicated.

[Derek]

No, that's right.

The jig- does it have two parallel grooves on each side? (to make sure we are talking about the same design)

Clamp the rail into one of the grooves on the side and the end with the appropriate letter (although there are some with the letters in the wrong place (like mine)- but you can of course work out which is which by looking from the side- shortest being A, longest being D). Make sure the clamp is over the foot to protect it, and file away the head. Then take it out and put it upside down, with the clamp in the centre or the opposite end and file the head and the foot away (this is the side that butts up against the stock rail). Having re-read the S4 guide, it makes the good point of filing along the rail TOWARDS YOU rather than pushing (which was resulting in my strange bends).

Take the side with the foot but no head, and lay it down on a straight object (glass or even the side of the jig- if yours is completely flat)- you need to make that rail dead straight against the glass/jig/ruler. After you've done that, you'll need to get rid of the burrs from filing- use wet and dry and try not to put a file on top of the rail.

I am finding that getting the rail back into shape after filing is harder than expected and- to my surprise- the manual filing method described doesn't bend the rail- so perhaps the jig isn't the best solution. I don't know...

This might be useful: (look for the post by JFS)
http://85a.co.uk/forum/view_topic.php?i ... forum_id=1

Or this:
http://www.scalefour.org/members/digest ... -6-1v2.pdf (READ THIS: It certainly put me right on several things I was doing wrong)

It does seem we are in the same boat though, wondering whether or not the blade jig is the best solution.

Derek

[jon price]

Ok Thanks for all this input. I suppose the thing to do is to play with it and see what happens. A few centimetres of rail is no great loss if things go wrong.

[Mark Tatlow]

I use ht ejig to get things going but then finish on the workbench; I do find I can hurt my fingers clasping the rail though!

What I would caution all about is how hard the steel to the filing jig is; it will blunt your files good and proper and I have now bought a second set as replacements retaining the originals just for rail filing.



Mark

[Terry Bendall]

What I would caution all about is how hard the steel to the filing jig is;

The jig is case hardened so that it does not get worn. The idea is that when you reach the top surface, you stop filing. However it does depend on the user being able to control the file and keep it moving horizontally rather than allowing it to rock. Not an easy skill and practice is needed. The best way for a right handed user is to hold the handle in the right hand and put the first two fingers of the left hand on the other end so that pressure is applied evenly at both ends of the file. For left handed users it is the other way round. Letting the file rub on the top surface will certainly blunt it.

Howard Bolton will be at Scaleforum and his help desk will no doubt cover this part of the process. He may even have jigs available but if not I will let him use mine.

Terry Bendall

[Derek]

Hello Terry,

You showed me where I was going wrong on a lot of things at Wells- I didn't describe too well what was going wrong, but having once been there yourself, you seemed to instinctively know.

Two questions for you if I may (and I have asked others for their opinion on this too- I'd be interested to read yours):

1. Do you personally file, bend, file again, or do you just file and then solder? There are some really talented people on each side of that debate!

2. When offering up the planed blade tip to the stock rail immediately after the set, on the prototype it sits hard up against it. On the model you don't have the high clamping force to hold it close. On the model you can see the line between the two, which is exaggerated due to the curve of the rail top and the 1:20 lean of the rail- that is making the blade appear to bifurcate from the stock rail just slightly before SG. Some seem to say "if it works, live with it" and others suggesting that this is a heinous mistake. Opinions?

Apologies to Jon for hijacking his thread and I hope he will find any answers as useful as I will...

Derek

[grovenor-2685]

I'll give you my answers and you can compare with Terry's and anybody elses.

1. Do you personally file, bend, file again, or do you just file and then solder? There are some really talented people on each side of that debate!

You need to bend at some point in the process or your gauge face won't be straight, but when exactly you do it is a matter of developing your technique, I usually do the bend after filing the stock rail side and then the gauge face but there will always be a bit of fettling to do after that.

2. When offering up the planed blade tip to the stock rail immediately after the set, on the prototype it sits hard up against it. On the model you don't have the high clamping force to hold it close. On the model you can see the line between the two, which is exaggerated due to the curve of the rail top and the 1:20 lean of the rail- that is making the blade appear to bifurcate from the stock rail just slightly before SG. Some seem to say "if it works, live with it" and others suggesting that this is a heinous mistake. Opinions?

The prototype can plane the blades very accurately so the 1:24 or whatever angle will be just so and hence the whole of the planing will sit up tight to the stock rail. Its not so easy filing the blades by hand and since a short planing length will definately be a problem we tend to err on the side of a bit of excess planing. Then if you put the set at the correct angle the planing will show a gap towards the heel as you describe. So long as the tip fits well and you don't have any gauge narrowing through the switches it will be just fine functionally. The issue is a cosmetic one and only you can decide what you can live with and hence how much care and time you put into getting perfection!
Regards

[Derek]

Many thanks for that, Keith.

I know you are on the side of bending the vee. (like I said- I've asked several talented people and got a 50/50 response- in "the other place").

Can I explain my reason for asking this? I can see the reason for getting a solid point- aside from the aesthetic reasons, if you try to file to a sharp point to get the splice rail in line with the stock rail, you'll have nothing at the end. If you are filing a rebate (good luck) then I'm not sure you would need that- like wise with the blunt nose, you don't need to file so sharp. However following advice previously given, I bend the rail to "approx. the right angle"- file away that bent bit and then stick it in the jig to get the vee angle right (I know you do it by hand- and I salute you for it). The thing is, doing so introduces a risk that when filing away the bent part that you lose the dead straight edge of the rail- not easy for beginners.

Thank you for your clarification on the blade-stock rail part. I can live with it and It is barely noticeable. It works without any bad running, which is the main thing. I'm sure in time I can get that gap down even further.

Many thanks
Derek

EDIT: BTW after trying both your method of manually planing blades and using the jigs, I have come to the conclusion that manually is a better way. I like the vee jig- not so keen on the blade jig.

[grovenor-2685]

Derek,
I though both your questions related to the blades. For the vee its, perhaps a matter of preference, but I see absolutely no advantage in omitting the bend and having a missing section of web as a result. I haven't used the jigs but the way they work is to allow you to file the final angle, so file the gage side first just down to the web, make the bend then put it in the jig and file the other side to the angle.
Regards

[Derek]

Thanks again Keith.

When you say you are bending the blades, do you mean just to straighten any bends you've induced during filing? Sorry, I think I've missed something somewhere. I will go back and read your excellent article.

I've messed around with these blades so much now that I don't actually know what I have or haven't done in any case.

[grovenor-2685]

When you say you are bending the blades, do you mean just to straighten any bends you've induced during filing?

Well, you may need to do that, it does sometimes happen
But when you file the blade you take some off the back and some of the gauge face, preferably only from the head. Then, just like the Vee really but a smaller angle you need to bend at the end of the planing so that the gauge face is straight and all of the taper appears on the back to fit against the stock rail.
Regards

[Will L]

I think Keith is being polite. To produce both the planing on the point blades and to produce a decent crossing V, it is highly desirable to file metal from both sides of the rail so that the sharp end has metal across the full depth of the rail. So both for the V and the blade you file one side to half the angle required, bend from the end of the filing so you have strait edge on the rail, then file the full angle on the other side. This is essentially what they did on the prototype so in P4 you would expect to emulate them. As for the experts else where, well there is always somebody who can make the strangest methods work, but if you want to do it properly.....

These filling jigs are OK but with a bit of practice it really isn't that difficult to do them without. All you need is a simple jig to give the required angle which you can make out of two bits of sleeper strip glued to a flat surface meeting at the required angle. So you file by eye then check where you are by using the sleeper strip jig which to my mind is better than relying on the filling jig and having no other direct check that you've got it right. You can also use the sleeper strip jig to assemble the V where it is more important that the V is assembled to the right angle than the filling is absolutely accurate as the solder will fill any gap.

[jon price]

Well there is a lot of useful stuff about making Vs here, and I don't see any problem with the discussion broadening out in that way, but that doesn't answer the question of how to use the blade filing jig. Can anyone who uses one (as opposed to those who can magic blades up by eye reckoning) post some images showing how they work? The only image I have found elsewhere shows a blind jig (no rail inserted) with a second screw holding a washer. This isn't present on the jig I bought, possibly because it gets in the way of the file. Or posibly not, I don't know. Anyway, some illustrated instructions would be useful for those of us who have not yet been admitted to the 15th degree of the Chapter of the Rose Croix of turnout mastery.

[Derek]

Jon

Sorry for hijacking your thread.

My jigs are at work. I will make some photos up in my lunch break for you.

[grovenor-2685]

You can also use the sleeper strip jig to assemble the V where it is more important that the V is assembled to the right angle than the filling is absolutely accurate as the solder will fill any gap.

All illustrated here http://www.norgrove.me.uk/points.html
Regards

[jon price]

I dont think "my" thread is hijacked. This is all good information and discussion. Keith, your stuff on your link is excellent and precisely what I'm looking for, but as you yourself say "You will notice I have skipped actually filing up the blades, for some reason I missed taking photos of this bit."!

[grovenor-2685]

I'll try and do something about that bit
Not going to be very soon though, its tricky getting decent photos of blades and I'll probably have to do some drawings as well.

Its fairly well covered in the original P4 manual however, that's where I started.
http://www.scalefour.org/history/p4trackcon.html
I don't use the overhanging formica idea, I haven't found it neccessary but it might help if you want to make GWR curved switches.
Regards

[Derek]

Hello Jon

Have a look at

http://www.whitby50g.co.uk/en-gb/turnoutblades.html

I've knocked up a couple of quick photos. I didn't have time to file new blades so just posed it with a couple of blades that I made just after I bought the jig. They are a little chewed up. I would recommend not going for such coarse files as I've shown there either- it was all I could find to hand.

One thing more, when filing (and this is especially important when taking the head off the inside of the rail and you have the clamp protecting the foot) try to use a safe edge file and certainly not one that comes to a point at the side (triangular or semi curved) as you will eat into the clamp- not that I would know this of course.

That is pretty much how to use the jigs. I have already greatly improved on the quality of what I am making now compared to those blades (and my first couple of turnouts) after I bought the jig. Still not great, but improving. Now it's just a case of continued practice by learning from the great masters such as Keith and Terry.

Derek

[jon price]

Brilliant, thanks. I think I have suityable files so I'll start filing and see where I get to. I hadn't actually realised that both ends of the jig come into play.

[Mark Tatlow]

This should be downloadable (he says hoping he has mastered this IT stuff...........)

It shows where the point blade should be filed. Please note that the arrow that shows which side is up for each view is important.

2698 - Copy.png

[Will L]

...Have a look at

http://www.whitby50g.co.uk/en-gb/turnoutblades.html

I've knocked up a couple of quick photos. I didn't have time to file new blades so just posed it with a couple of blades that I made just after I bought the jig. They are a little chewed up. I would recommend not going for such coarse files as I've shown there either- it was all I could find to hand.

Oh dear and oh yes, you do need a much finer file. A 4 inch Vallorbe engineers file from Eileen's is ideal and they look like this

For preference you need both a Fine cut and medium cut. Give the size of the stuff we produce, and the materials we use you don't need anything courser. Same thing available from elsewhere (e.g. Shesto) but Eileen's price is very competitive at the moment.


These are by far and away my most useful files and I wouldn't be without them.

[Derek]

Jon,
just remember that rail costs pence per foot wasted. Just keep practicing. I have (to paraphrase Edison) invented 500 ways to make poor blades and vees. I have started this recently enough to remember that it is blasted frustrating to get it right- especially as the experts make it look so easy.

Although I am still asking the experts their opinion on different methods (as we've seen here) nothing beats having a go and finding the 501st way not to get it right.

Will,
Like I said, it was just a file that I had to hand at work. (a heavy vehicle repair centre where fine files are not really used). I used that coarse file at the beginning as I was impatient waiting for the finer ones to arrive. That said, I did manage to produce some quite decent blades with that file, some cheap expo files from the local shop and some wet and dry that I had lying around (all high tech here).

[Derek]

Apologies for the double post- ie seems to be having problems with clicking buttons (not just this forum either so must be my pc).

Jon,
Have you looked close up at a turnout on a real railway? A lot of what these chaps say made much more sense after going and looking at our local heritage siding that masquerades as a steam railway, and seeing a real turnout and how it is constructed.