Cut-Off Wheels

[Curtis Kyger]

I'd like to cut electrical isolation gaps in existing Code 55 track and I'd like the kerf to be 0.010" or less.  I'm thinking of a cut-off wheel that will fit the typical Dremel No. 402 mandrel and be about the diameter of their No.409 (0.0245" thickness) and 420 (0.038" thickness) cut-off wheels. Suggestions?

[wazzou]

https://www.dedeco.com/

[C855B]

Specifically, Dedeco 0.015" cutoff wheels. They're much more durable than the stock Dremel wheels and less likely (that's LESS likely, not UNlikely) to fly into a hundred bits if you put too much side pressure on 'em.

[peteski]

My friend used standard thickness Dremel cutoff wheel to cut gaps, then he glues in (using CA glue) a piece of styrene to fill the gap, trims it close to the rail with a knife, and files the top flush with the rail. Once the  rail is weathered, the gap is basically invisible, and because it is filled with styrene, there is no chance it will ever close up.  Same process could also be used for gaps cut using thinner cutoff wheels.  I have some thinner ones, but I think mine are also made by Dremel.

[robert3985]

I think @DKS  recommended the ideal cut-off blade/wheel here at TRW a while back.  Maybe he'll chime in with the answer.

Cheerio!
Bob Gilmore

[samusi01]

Dedeco (@C855B and @wazzou suggested) have also their product 5173, 0.009” cutoff discs. One does have to be quite careful as they aren’t as durable due to their thinness, but they are quite thin… I usually get a few (2-3, maybe more) gaps cut before I get careless and the disc is destroyed.

That said, I usually tend to use the method suggested by @peteski with styrene.

Sam

[davefoxx]

I just use an Atlas track saw.  Takes less than ten seconds, and the gap is probably only 0.010” wide.  No exploding cutoff disks, and I think it’s a more precise job.

DFF

[DKS]

I think @DKS  recommended the ideal cut-off blade/wheel here at TRW a while back.  Maybe he'll chime in with the answer.

Cheerio!
Bob Gilmore

I don't recall making a recommendation. But, as it happens, I recently ran out of standard cutoff discs, and in order to keep working, I switched over to the Dedeco discs I had on hand. I have their 0.0064" discs, which are incredibly thin and incredibly delicate. However, if you work very, every carefully, they last a lot longer than expected and, in particular, they produce remarkably clean cuts with a near polished finish. They also cut much faster because they remove far less material. Now I'm using the super-thin discs for just about everything. For rail gaps, the cut is so fine as to be almost invisible. I think I managed to make about a dozen gaps before the disc gave out. As an aside, on the occasion I need something more robust, I just sandwich four or five discs together.

[C855B]

I don't recall making a recommendation. ...

You did, 10 years ago: https://www.therailwire.net/forum/index.php?topic=24433.msg239655#msg239655

[davefoxx]

Oh, and while I'm thinking of it, definitely get some styrene in the cut.  I had a turnout go out of gauge after a few seasonal changes on my then-new layout, I made a cut, hoping the saw kerf would relieve the pressure.   It worked beautifully.  But, although it's back in gauge and all is well, that gap closed up since.  Had that been an insulating section, I would have had a short. 

Another reason for those of you who use Atlas flextrack: that loose rail will migrate.

DFF

[John]

Oh, and while I'm thinking of it, definitely get some styrene in the cut.  I had a turnout go out of gauge after a few seasonal changes on my then-new layout, I made a cut, hoping the saw kerf would relieve the pressure.   It worked beautifully.  But, although it's back in gauge and all is well, that gap closed up since.  Had that been an insulating section, I would have had a short. 

Another reason for those of you who use Atlas flextrack: that loose rail will migrate.

DFF

I just did that today -- I replaced an entire section of track between a couple of those curved turnouts I got from you .. the gap I had cut for the detection block went out of guage on the curve -- tried to fix it with some PC board ties -- decided to just start over ..