Nova Slot Processor Repair

[GoodOldNorm]

My Nova tank had a crack around the top of two dividing sections as shown in photo 1. The tank was thoroughly washed out and then dried for three days near a radiator. Using a cotton bud I then cleaned the crack with some upvc cleaner (acetone). You can use petroleum ether and then wash it off with water but I did not want to have to dry the tank again. A ratchet strap (with blocks of wood to protect the tank and apply pressure where it was needed) was placed around the tank loosely. I gave the tank a blast with the wife's hairdryer to drive out any remaining water from the cracks. The Tensol 12 was taken out of the fridge and dripped into the cracks, I helped it into the cracks using a long matchstick and tilted the tank accordingly. Alternatively you could use a syringe.The ratchet strap was then tensioned to close the cracks. Be carefull not to apply too much pressure as the tanks are in my opinion quite fragile. I then left the tank to dry.
http://www.film-and-darkroom-user.org.uk/forum/attachment.php?attachmentid=2210&stc=1&d=1417882199
I also experimented with glues I had around the house, Tensol 12 as expected made a firm contact and held fast, it actually melts into the surface of the acrylic. Araldite made an equally strong joint and had better gap filling qualities because of its thick viscosity. Full strength super glue was not a great success, the bond between the two pieces was easily broken. Fiberglass epoxy resin hardly made any kind of bond at all and it was easy to snap the two bits of acrylic apart. If I could not get hold of Tensol 12 I would not hesitate to use Araldite, but beware that as pointed out by one of our friends on the forum darkroom chemicals can attack and breakdown Araldite over time. I would not attempt to build a tank using a two part epoxy resin but I am confident it could be used to make a small repair. The Tensol 12 was purchased from Trent-Plastics (Gainsborough) on Ebay at a cost of £8.85 including P&P (it was delivered the next day). Tensol 12 is quite thin, there is another type of Tensol called Tensol 20 that is thicker and has better joint filling capabilities but it is much more expensive.

[Luis]

Nova once sent me an acrifix sample and worked like a charm

[GoodOldNorm]

Nova once sent me an acrifix sample and worked like a charm That is correct The Imaging Warehouse also sell the acrylic cement which is listed on their website.

[John King]

I wish my processors were as clean as these.

[Mike O'Pray]

I wish my processors were as clean as these.

Well in my experience it can be done John. It just requires some household bleach that hasn't been diluted to death and patience that lasts for up to several days. Oh and a bottle brush that is deep enough to still give you "purchase".

Unfortunately it doesn't make your prints any better anymore than a clean car goes faster:D

Mike

[Luis]

I wish my processors were as clean as these.

There are a few commercial processor cleaners which work just fine. Alternatively home mixed TC1 always did its job for me.

[GoodOldNorm]

There are a few commercial processor cleaners which work just fine. Alternatively home mixed TC1 always did its job for me.
Hello Luis. I use Tarbuster but its expensive, what is home mixed TC1 and how do you make it? Thank you.

[Mike O'Pray]

For what it is worth I found that Tarbuster is excellent and reasonably economical for ridding the slot of developer tar, especially RA4 developer but nothing like as good for fixer stains where good old fashioned household bleach and a bit of time seems to work better and quite cheaply

Mike

[JOReynolds]

Hello Luis. I use Tarbuster but its expensive, what is home mixed TC1 and how do you make it? Thank you.
Tar is soluble in 5% w/v citric acid solution. Crystalline citric acid is sold in home-brew shops and is quite cheap. It dissolves easily. A good soak is best - no need to rush. Block up overflows to raise the liquid level and clean around the tide-line.
Citric acid 2.5% makes an excellent non-smelly stop bath.

[Luis]

Tray Cleaner 1 (TC1)
1L water
90gr Pot. Bichromate
96ml Sulfuric acid, concentrated.

I've used it fillling trays, slots, or just scrubbing with a brush soaked in it. Then rinse. Use protection (gloves, lab coat, eye protection) and common sense from mixing properly to use; you don't want the stuff splashing everywhere, isn't healthy and – ironically – it stains. On a glass stoppered bottle it lasts nearly forever, I keep using the same solution for longer than I can recall.

TC3 is less aggressive, and still a good cleaner in two solutions, but I don't have the formula at hand. IIRC it had sulfuric acid, and pot. permanganate in a far lower concentration.

Jobo processor clean does the trick too, but ain't cheap, probably in the same league than Nova's. Also there is – or was – a third product from tetenal, but can't tell you about the price.

[Stocky]

I have used Steradent for years. Now I have found that its active ingredient, sulfamic acid, is available neat in hardware shops at a fraction of the price I'll start using it.

[GoodOldNorm]

Found another glue that works very well EverBuild stick2 Hard Plastic Adhesive

[John King]

For what it is worth I found that Tarbuster is excellent and reasonably economical for ridding the slot of developer tar, especially RA4 developer but nothing like as good for fixer stains where good old fashioned household bleach and a bit of time seems to work better and quite cheaply

Mike

Tarbuster is fine but unless it is done outside or in a well ventilated room the fumes will do damage to your respiratory system plus it is very expensive for what its worth.

I found out by accident the cleaner used to brighten up alloy will work much better. I use alloy cleaner as sold by Tool Mart at £3.75 a litre. Based on Phosphoric Acid, it has very little smell and really shifts the muck.

It will NOT remove staining where bleach has broken down and entered the surface of the glossy acryilic (neither will Tarbuster) So if they have been used for a year or two on a regular basis there is no way anything will remove the marks.

[KevinAllan]

I broke my Nova tank by stepping on the base just after unpacking it after purchase; Tensol 12 came to the rescue and so far it is holding well.

[Martin Reed]

The most common problem with Nova units is breakage of the water inlet or outlet pipes. If this happens to anyone else maybe give Novocrylics, the manufacturer, a ring. Breaking these off, especially the little water inlet pipe, has happened many many times - they should be able to supply a repair kit, replacement pipe + cement. Then it's just a matter of carefully drilling out the stump & putting the new pipe in.