Altman 3.5q repairs

[Ben Kent]

Hi,

My theatre has a large number of Altman 3.5q Elipsoidals. It seems that almost every one of them has the same problem. The shutters are very loose and unable to be put into any useful position. I have opened up a few of these fixtures to attempt a repair, but I can't figure out a way to tighten up the pressure plate in order to make the shutters work properly. Does anyone have any tricks when it comes to performing maintenance on these lights? Usually with elipsoidals, I can figure out a way to tighten up the shutters, but It doesn't seem to be possible on these lights.

I could order new pressure plates and / or shutters for our whole inventory, but I'd prefer not to spend the money on these fixtures, and I'm not sure there's any guarantee that will fix it.

 

[RonHebbard]

Hi,

My theatre has a large number of Altman 3.5q Elipsoidals. It seems that almost every one of them has the same problem. The shutters are very loose and unable to be put into any useful position. I have opened up a few of these fixtures to attempt a repair, but I can't figure out a way to tighten up the pressure plate in order to make the shutters work properly. Does anyone have any tricks when it comes to performing maintenance on these lights? Usually with elipsoidals, I can figure out a way to tighten up the shutters, but It doesn't seem to be possible on these lights.

I could order new pressure plates and / or shutters for our whole inventory, but I'd prefer not to spend the money on these fixtures, and I'm not sure there's any guarantee that will fix it.

@Ben Kent Have you tried the old standby of pulling the shutters out to their normal end of travel and bending them hard either towards the front lens or the lamp, one way or the other, then forcing them in as far as you need? This was a common quick fix with most ellipsoidals and would usually last long enough to get you through the run of a production. Not being familiar with your particular fixtures, what normally applies pressure to the pressure plates?
Toodleoo!
Ron Hebbard.

 

[derekleffew]

I'm sure @ship will be along shortly to provide the correct answer. He is the KING of 3.5" ERSs. I've never particularly liked them.

Until then, a "trick" that works for the full-size: pull the shutter out all the way then bend the heck out of the handle (tab) like almost 90°. Push it back in to where you want it.

(Posted simultaneously with the above.)

 

[Ben Kent]

@Ben Kent Have you tried the old standby of pulling the shutters out to their normal end of travel and bending them hard either towards the front lens or the lamp, one way or the other, then forcing them in as far as you need? This was a common quick fix with most ellipsoidals and would usually last long enough to get you through the run of a production. Not being familiar with your particular fixtures, what normally applies pressure to the pressure plates?
Toodleoo!
Ron Hebbard.

They don't appear to be particularly well designed. The pressure plates are just attached by four screws through the body of the light which offer no adjustment. The only method of pressure I can see is a small divot on the plate where each shutter is. I have tried bending this, but don't appear to be able to bend it enough for it to make any difference. I will try bending the handles as you suggested, to see if this will be a temporary fix.

 

[JD]

Used to have a lot of these on a show in the 80's but didn't have that problem too much as they were way, WAY over-lamped (for purpose of Rock and Roll) so the shutters warped on their own
I have had to deal with this before on other small fixtures, and one solid fix was to add a punched round plate, similar to the gate plate, to the stack so there was less clearance.

 

[Les]

Here's a trick I've used on 360Q's, which are essentially the same design only larger.

• Remove the shutter completely
• Find a table with a nice square edge
• Lay the shutter at the edge of the table, so the centerline is hanging 50% over the edge
• Give the shutter a little bend

The idea is to bend the shutter longways, rather than cross-ways (see picture below). Doesn't have to be a significant bend - just enough to give it a little more friction between the plates. Too much of a fold might give the shutter a higher vulnerability to heat in that area.

The shutter might still have the tendency to pivot, but it should be worthwhile to try it out on your most temperamental fixture and see if it makes life easier.

To remove the shutters, you'll need to take the insulated grip off if they're anything like the 360Q's (which I can't remember). Most people will drill the rivet out and pop in a new one later, but I've found that simply grinding the rivet flat will give it enough clearance while still holding the insulated grip — or at least I've never lost a grip this way. Again, that's the case with the 360Q, but I haven't worked with the 3.5Q recently enough to remember if this is the case.

A centerpunch on the spreader plates as @JD suggested might work wonders as well.

 

[ship]

don't have one at home - I have the Kliegl version hanging above my work table at home. Have to verify with the one in the museum the below fixes.

I do have the exploded pictorial thumb tacked to my wall though.... part 20-0246 is the tensioner plate, 20-0247 is the spreader plate. The above "adding a second spreader plate" is a really good idea. Though given it's about a 18ga steel, I might try to make spreader plates out of like 20 or 22ga plate. A second 18ga steel spreader might get it too tight. Put the added spreader plate against the tensioner plate instead of sandwiched to the spreader plate.

I have never seen this problem before - my nemesis was Colortran Mini Ellipse shutters and 1KAF 6" Fresnel focuses.

Another option is if not replacing the tensioner plate, to further dimple it assuming a 360Q style tensioner plate. You would drill a small hole into a steel or aluminum plate with a 3/8" 135 degree drill bit just enough to get a concave shape. You would than round over a 3/8" punch and attempt to make the flat part of the dimple in the tensioner plate a little more round. This would be a mild hit so as not to blow thru the material. Depth of the cup in the bottom plate material will be very difficult to determine in going just deep enough to tension enough. Perhaps a better way would be 3/4" 7-ply plywood without a dimple pre-drilled into it. New dimple each time in pounding the rounded over punch into it - again with only medium hammer pressure.

Normally on a 360Q there is a spreader plate between the tensioner and shutter though. The drawing I see on the 3.5Q series does not have a second spreader plate so I'm thinking there is no dimples to the spreader plate or if there is - they are rectangular which would be harder to dimple without cutting thru.

Sorry, been a few years since I took one apart. The drawing looks like the tensioner plate has tensioners which are cut in a rectangular c' shape and bent in towards the shutter. If the case, it would be simple enough with some sheet metal tools, or a 1/4" plate wedge and hammer to bend the tensioner out some more at the flange. If also the case of tensioners without a spreader plate, it might be that two spreader flanges are for direct contact with the shutter and two would be bent in a little more for contact with the spreader plate. If this is the case the tensioner plate is installed say 90 or 180 degrees installed wrong. Two shutters would be loose and two would be tight.

A further concept is that it's an Altman... and known about Altman and other brands is that not all parts are drilled to have the same holes for say pre-90's fixture design in holes not lining up fixture to fixture. If during service you swapped a tensioner part with fixture A to fixture B, the mounting holes might not align, but even if they do... it's possible fixture B' now is loose in tension. Its also possible that given manually drilled mounting holes, that perhaps the spreader plate was spun 90 degrees and does not tension properly.

What ever the case when I find this, I spin the tensioner plate a few degrees, load on around 20# of weight to the assembled shutter assembly and drill new holes into the tensioner plate. You now have tension on the shutters.

Paint these parts (except shutters) with high temp. flat black and coat all parts with high temp. PTFE. Take a scribe or engraver and mark whitness marks and matching #1 - infinity in matching spreader part location on the fixture and plate so re-assembly ensures this plate goes back to the same spot every time.

 

[ship]

Q of the day' given the 3.5Q series was the first Leko' invented with body to match the new concept of a workable halogen lamp... who did it first Kliegl or Colortran? Colortran documents are in this sites Wikipedia, Kliegl brothers has their own historical website.

On reply to Les above... I don't really recommend this or center punch pippling the spreader plate option mentioned and possibly deleted. A bend/fold is worse than say a curve say around a 5gal bucket. Both the center punch dimpling and hard angle bend will chisel a bit of any coatings on the spreader or other plates. This as with burnt shutters scraping away at the plates all which permanently will damage plates.

Try instead to spin the tensioner plate some, weight it with like 15-20# of weight or clamp it (never had much luck clamping it with that little amount of approximate pressure), and drill new holes. Better yet, since spreader plate holes are almost never really 90 degrees from each other, try spinning the plate 90 degrees, than another 90 degrees, than the third 90 degrees and see if you can get the spreader plate so no mounting holes align with a drilled hole. That way dimples will be in the same position to the shutter as opposed to a few degrees off. Drill new holes with the new weighted tension on the tensioner plate. (Have someone hold down the weight so all don't collapse while drilling.) Drill one, put a screw in, move you not the fixture onto the next hole. Drilled, screw in, move to the next.

Take a file and scribe or center punch and mark the proper position of the tensioner once done either way. Than if possible scribe, engrave etc a part number of it matching to the outer casing. This way next time it's apart, you can get it back together.

Also recommended my shutter and all shutter assembly resurfacing steps mentioned years ago, plus painting and PTFE or spray graphite to gliding parts.

On the grinding the rivet flush, I don't recommend this either - sorry. First if you re-install with only the shaft or somewhat left part of the rivet holding the fiber washer handle, it could fall off or break especially if the fiber washer is over heated from use or during the grinding. Second, unless you only have one fiber washer for a handle I doubt the more normal dual fiber washer would fit thru other than the gobo slot. Would be close if you were able to remove all spreader plates, but to what point given above?

I prefer first a 1/16" punch to pound out the shaft of the rivet. If you don't remove the shaft of the rivet, when drilling you might hit the shaft and your drill bit will bounce off center.

Clamp the assembly with medium/hard pressure in vise grips so they don't spin or separate. This will also help determine if your fiber washer was heat damaged in use - by way of breaking in which case you grind. Dependant on era, your shutter handles will either be using a 5/32" or 3/16" rivet. Just use a #11 number size drill bit with cutting oil and plan on making them 3/16" aluminum "sealing" with aluminum shaft surface mount blind rivet of about 1/4" and shorter grip length. Should be able to drill thru the actual shutter material with oil without dulling the bit if at full speed on a cordless drill. Remember - if using cutting oil, horse hair brushes hold oil and in general you don't need to soak the bit in oil or it will have to brun thru it before it does cutting. This much less the too much oil will damage the fiber washer. Otherwise in general especially if stainless steel shutter, having a carbide #11 drill bit would be a great thing with oil and full speed.

Aluminum/Aluminum shaft rivets will clamp sufficiently the fiber washers to the shutter without over tightening them and breaking the used fiber washer. Add a rivtet washer to the reverse side of the rivet so the riveting action of the pop rivet does not damage the Aluminum rivets bob into the soft or brittle fiber washer. Aluminum rivets also do not get as hot. The lower shaft of the "sealing" rivet will stick out some more than normal rivet, it's actually useful in focus. If you find the rivet broke its shaft before they were tight enough, a medium tap with a hammer on an anvil below the rivet on the shutter handles will tension them enough without damage.

 

[ship]

New thought is if the tensioner plate is considered as per a donut disc, that disc might have bowed inward towards the lamp some. This would reduce tension on the shutters.

I have also done this in the past on Leko's when such a bow was noticed.

First make sure your tensioner plate mounting screws are tight. Lens train barrel mounting screws are tight, remove the lens train.

Than open up the body of the fixture and put a thick 3 to 4" dia plate of steel at the center of the tensioner plate. (Might be 2.5" plate dia. needed for the 3.5Q). Give it a medium pound with a hammer. This will either correct a concave towards the lamp of the spreader plate back to flat, or covex the spreader plate outward some, it will quickly and easiest of all re-tension the shutters.

 

[soundofsparks]

I find that if you hit the little divots with a hammer (not insanely hard, but firmly) you can tighten up the assembly. It just has a lot of room to warp. Usually that fixes loose shutters.

Stiff shutters are usually bent shutters, so those you have to try to flatten. Hammer works here too.

If the shutters are stiff, but not bent, spray graphite helps.

 

[Ben Kent]

Thanks for all your help everyone. I now have a project for the next time we are dark.