Different styles of Simplex 70mm trap bands?

[Tj Hopland]

Later 80's Simplex seem to use a wider band in the 70mm trap compared to the 35. All the ones I have seen seem to be a rather crudely likely hand made units that don't seem to have the same surface as the 35's or the bends. Were there versions of these wide bands that came with the bends and had that nice chrome like surface? And what I have seen was just the later replacements they were sending out or that someone made up? They have that blue tinge that the back side of the ones Lavezzi made had but the Lavezzi ones seemed to have a chrome like surface on the film side. Or maybe its that the material is that chrome look and the blue is some sort of coating?

Recently was on a site with a 60's model and its got what appear to be the same bands as the 35. I didn't have a lot of time to carefully look or try swapping to prove they were the same but what I could see is those appeared to be correct for that trap. The little radius nubs they wrap around were just barely wider than the bands just like on a 35. The wider ones seen on the 80's version would not be well supported.

Has anyone else seen or remember both styles? Anyone tried running the 35 ones on a 70 especially one of the later 80's machines? The gate runners appear to be the same on both styles of machines which is more like the width of the 35 bands so is the wider band gaining you anything?

By the time I was taking care of the 60's machine it wasn't running a lot of 70 so I really don't know how well it did on long runs and it hasn't run anything in many years now so I can't really do any testing. The runs it did do I don't recall there being any unusual issues with stability or wear of the machine or film but this was still in the mag days with thicker stocks so things could be different now with the thinner stocks.

[Steve Guttag]

The 70mm bands (and gate runners) were always wider than 35mm. As many know, the Simplex 35/70 was not built around 70mm. While the pad rollers would pull out to that width and the lateral guide roller was for 70mm, the film was unsupported for that last 2.5mm on each side. This would put a noticeable wear mark on the mag stripes (When they were mag) as the intermittent shoes also were for the narrower spacing (fun fact, you can cut WAY down on the wear if you space the intermittent shoe out like a pad roller and put two thicknesses of mag striped film on the sprocket before setting the distance.

The 70mm bands should be polished. I seem to recall they were spring steel. I do recall them being crudely cut at their ends (not squared off but at a random angle).

I wonder what Strong did with all of their drawings and information on how things were made. Did they just pitch it or store it with ark of the covenant.

[Tj Hopland]

Ya we could spend a lot of time talking about the design of the Simplex 35/70.... Yes those pad rollers were among the many stand out I guess features?

I did manage to get a picture of the 60's gate and trap that brought up this question. Its fairly likely this stuff is what it came with when the machine was new. I do know in its original home it barely ran any 70 so probably never had to replace parts like that. When it moved to its 2nd and current home it was a tight budget as is thing so it didn't get any kind of a full replace everything rebuild. There it did so some 70 but no long runs so not that many hours total.

At one point the machine got a full rebuild but I seem to recall by then it had been a while since they had run any 70 and it was just before DTS became a thing so there wasn't really any talk of new prints so we didn't really put any real resources into the 70 side of things at that time. Parts would have certainly been readily available at the time so if anything was replaced there would not have been any need to get creative and substitute things.

gatetrap25.jpg

[Josh Jones]

Did this come from a place I know? The carpet looks familiar.