advertisement


Cracked Acrylic - how to repair?

well I got the mystery solvent, and it will have to remain a mystery - no indication of content at all.

I suffered an attack of the trembles when I was cutting the seal on it, and some spots of it landed exactly where I didn't want them to go - on clear perspex. So I left it for 5 mins, and it left milk spots. Perplexingly (perspexingly?) they polished out with about 30 secs of microfibre cloth work.

Disaster out of the way, and I applied to the crack area. Partial success - one end of the crack is within the perspex itself, the other surfaces - and it appears that the solvent evaporates too quickly to allow capillary action to reach the depths, so one end is sealed, and the other will just have to be as it is. I shall paint the recess area to neaten it up - possibly gloss black to match the platter.
 
OK, had to shelve the project because ill, but now back "in the groove." Annoyingly the spots have reappeared, either I was blind on the day or, well, I don't know.

Rather than ty to polish the damn things out, going for a carbon fibre veneer to cover the top surfaces of the acrylic plates. I'm not a fan of fake CF, so found a company that makes a .25mm thick genuine carbon fibre sheet, available with a 3m self adhesive backing. Cuttable with scalpels or stout scissors.Got an origin live VTA gubbins to go on, annoyingly Cherry Audio are now producing a platter with the 12 weights like I wanted in the first place, but this one will look fine. Analogue Seduction have been wonderful, managing to get Heed to ship a PCB for the Orbit 1 (replaces the Rega PCB), I can see why they don't give instructions for fitting since the board is so clearly marked with which wire colour goes where.

The annoying part of the project right now is that my ex seems to have had a spree of kleptomania on moving out, so my "special bits" box which contained a bunch of rather nice stuff - stub ends, counter weights, really nice looking (but unknown make/model) VTA adjuster etc, appears to have been emptied. I've got what I need to get the project underway, hey-ho. All part of life's rich tapestry, and I shall buy a voodoo doll kit shortly and scavenge some of her hair from the bath plug-hole. I hope to be doing a dry build (admittedly with a lot of help) this weekend, fitting the CF and doing a proper build prior to final fettle next weekend.
 
Too late now, you probably have already been working on a solution.

There is a special product to glue acrylic. Unfortunately forgot the name.

I bought it around 14 years ago it and was told it was used to fix the canopy on gliders (sail plane). I bought it at a place where they sold perspex.

I forgot what I bought it for but a year or two later my daughter had the taillight of her car damaged and a new one was pricey. I glued it up and no more leaking and it worked a treat, still working as expected 5 years later when she sold the car. It's kind of a filler, does not flow thinly but dissolves the acrylic and leaves something of a bead (like welding steel). I've been told one can machine/file/sand it down and then polish it and it will be unnoticeable.
 
Back in the 70's, when I started work with ICI, access to chloroform was restricted, in fact, all but banned, acetone, we slopped about by the 10's gallons, literally, the factory used (and recovered) thousands of gallons per week. You would rather use an anaesthetic than reasonably harmless, but flammable, acetone?

Chloroform is tricky to source for Joe Public for very good reasons.

http://www.labchem.com/tools/msds/msds/LC13040.pdf

http://www.labchem.com/tools/msds/msds/LC10420.pdf


It's OT but my grandfather, a Pharmacist, I remember watching casually fix with chloroform the broken diffusers to the kitchen overhead lights he'd unintentionally caught with the stepladder. Outside on the patio table, obvs. It's just what he had to hand at home... (late 1970s)

(Around the same time he taught me how to sharpen 2" Stanley Plane blades , the compound angles and such, how to get a straight and trued plane cutting edge - by touch, and the newspaper test etc - aged six. Then sent me home with the whispered suggestion, ...oh, and don't tell your mum...

I can still do it; makes me smile every time! Bthdth present aged 8 - a Plane of My Own. I still have, and use it. and the many he'd collected and left. Joy.)
 
Kintsugi.

I hope I have spelled this correctly. Its a Japanese technique, of ancient origin.

They use it not to disguise, but to enhance the appearence of and repair broken items- most often pottery- valuable teacups- and teapots. They use gold to fill the cracks, and, I cannot remember whether they start with a cement or not. You can look it up.

I have crockery that I have used for decades, some with serious cracks. Some were dropped. These had badly broken pieces (once upon a time). Some cannot be easily replaced, some no longer made. I am thinking of a set of Wedgewood Christmas platters- one of enormous size that I repaired. It will probably go on for centuries. A lovely antique set.

I use araldite- or some other permanent epoxy. It turns yellow or yellow/brown after a while. The odd colouration adds to the 'Kinsugi' charm.

Epoxy is to be applied to both sides of the crack/repair- i.e. the underside as well.

It should work well on acrylic TT covers- and have no dangerous fumes to avoid....if in doubt, open the window and hold your breadth- for hours- until it thoroughly dries (usually 24 hours. You can do it!!
 


advertisement


Back
Top