Too Much Coffee

Hi, I'm looking for help with regard to finding a suitable insulation material (and any installation tips) for my roaster. I'm not sure exactly what material is in place at the moment but what is there is just about at the end of any serviceable life i.e it's shot to bits and becoming heavily eroded!! The roaster is an 1984 model and I'm sure that it's original insulation would have been the big nasty 'A' word. However, I don't know if the original insulation may have been changed out along its years of service (I hop it has) and I don't know how long insulation materials may be expected to last for, although, I'm sure usage/storage/ambient/burner conditions etc. will all affect its lifespan. The current insulation is a board type (12/13mm thickness) which is doubled up to give about 25mm. There is a blanket type insulation around the arch of the drum housing although this appears to be in good shape.

Any help at all would be gratefully received

Craig.

Hi Craig! If there's a change it contains asbestos, please get somebody who knows this stuff to look at it first. The health danger of this stuff cannot be overrated, especially when it is not completely contained within a case!

If it's not asbestos, well How much space do you have for the insulation? If there's enough, the easiest thing might be a temperature resistant glass wool. I've only insulated a 300g electrical roaster so far though, so I'm definitly no expert in this!

Good luck!

Thanks Lukas for your reply! I managed to get confirmation that the insulation was not asbestos and armed with that knowledge, and much relief (understatement!), I removed all the retired insulation (masked, tyvek suited and outdoors!). I am now awaiting delivery of some new body soluble fibre board for the firebox and body soluble wool for the arch of the drum housing. This stuff is regarded as safe and non carcinogenic as the fibres are somehow diluted by bodily fluid and do not remain in the body! - or so it says!! Perhaps down the line it too, like ceramic fibre and asbestos, will also be found to be unsafe - Oh well, until then!

Not sure if I should make this a seperate post but does anyone have any recommendations for a suitable paint that I could use on the face plate, pipes and chaff collector? Original covering is a peeling powder coat I think. I'm looking to either paint or spray. I haven't been able to measure surface temperature of 'hot bits' as yet but exhaust temps are at 250c or so.

Thanks again
Craig

Hi Craig,
I've had to bite my tongue the whole time about that asbestos hysteria, but now that you have that topic sorted there's no reason to let it distract from the problem at hand.

A good paint shop can recommend high-temperature paints. They may not have them on hand and have to order them, but there are paints that can withstand very high temperatures. Shops that deal with tuning parts for cars sell paints for exhaust systems. Some of them are 2-component that have to be mixed before applying, but others are just one component. There are also many stove enamels that can handle up to 400°C or more.

If you Google Thurmalox, Halfords, Krylon or Alvin Products High Temperature Paints you will also get many hits. In any case you need to follow directions about surface preparation before painting very carefully or any paint will peel after time.

Good luck and let us know how you do with this. Also some details about roasting with this machine would be most welcome (pictures).

Good idea Bruce, I can also reccomend the paint I use on my wood burner stove. You can get it from most fuel merchants. Not cheap and only in small tins but it will be enough for your purposes.

bruceb wrote:Hi Craig,
I've had to bite my tongue the whole time about that asbestos hysteria ......

I am with you on the hysteria surrounding asbestos but wonder about the advisability of biting your tongue. Could this be why the coffee tastes bad?

Oh my! I'm probably a bit oversensitized as the whole university building was kind of decontaminated and sealed and everywhere are these 'do not open this panel! asbestos!' stickers around. Is it not as dangerous as some people like other people to think it is?

Hi guys,
Thought I'd update you on the progress of the Samiac and attempt adding a couple of pics too! The pic of whole machine (without chaff cyclone) was taken shortly after I got the machine and you can see the state of its insulation!

Then the new stuff -body soluble refractory fibre board good for 1260c! (came as a 1200mm x1000mm x 25mm board) This stuff was actually quite pleasant to work with! It cuts really well with a saw (normal and plasterboard) making shaping easy and is very rigid which takes the worry of butting it up close out. The only headache I had was removing the base plate of the firebox when off of the machines frame. The nuts and bolts and machine screws were well and truly rusted up, so a couple sheared despite using dismantling lubricant. I thankfully managed to borrow an impact driver to work out the screws which saved me having to tear down the box further (with hammer! -not sure I'd of got it back together again after that!).

Just a question about posting pics. I've noticed on other threads that pictures can appear without the box around them, how do I achieve that? Also, do pics always appear in the reverse order that you upload them in? sorry to ask, but I've never done it before now, and I'm hoping the resizing using irfanview worked ok too!

Most of the paint job has been done too, using rustoleum high heat stove aerosol- for the end plates (cured prior to new insulation going in) this worked out reasonably well although a touch up may be necessary. Body panels were done in red hammerite smooth (brushed on) and I have to say that I'm not that keen on it (either using it or the colour! - I liked the original vintage maroon/burgundy- but it had to be done!) but one day I hope I can have her sand blasted and powder coated (oooh and re-chromed!).

Anyhow I shall post some more pics soon and thanks for your replies

Nice work, keep 'em coming.

Could you please take some detail shots of the drum and vanes?

What is the red tap(sticking out from over the tryer) on the front for?

Hi isjms,

Here's some pics of drum (internal / external) for you showing vane formation. I don't know how these compare with other brands but the end result is a nice even roast.

The red tap is for a water pipe into the drum, my guess is it's a safety feature for a drum fire, although the nozzle on the inside of the faceplate has a pretty small apperture so perhaps a haphazard water quenching system! (I think some roaster's do do this internally as opposed to manually done on dumping- I'm not a quencher myself) I will most probably blank it off.

What's the opinion for a small fire for a drum clean?!!

The only roasting fire I've had was on my gene in the small chaff collector after 11hours back to back roasting! (It did melt a wee bit) I got a bit lax emptying it out after every couple of roasts towards the end of the session! The smoke must have been getting to me!

Cheers,
Craig.

This the evening project!!

But need pennies!

Wonderful pictures and wonderful work, Craig. We'll be looking forward to more pictures and reports on how the roaster turns out. I think you are right about the water quenching system. This was a common feature on some roasters for awhile. I don't think it is in favour much anymore.

It will be fun to watch the Visacream 2-group go back together. When you do get around to it please start a new thread so it doesn't get lost here.

As pictures, if you want them without frame you will need to put them up on another website like Picasa or a personal site and then link to them in your TMC post.

And yes, the pictures always turn up in reverse order. It's just the way the forum software works with them. It does take some getting used to.

Thanks for the photos. How's it coming along?

Not to sure about the drum fire, with a low charge weight perhaps it gets the job done quicker. I kind of like the idea of seasoning the roaster with coffee oil rather than soot. I intended to just roast a couple of dark batches in ours before trying the coffee, but lost control of the first couple of roasts anyway!

Here's an update on the progress of the Samiac! Most of the work has now been done and she's nearly been reassembled.

All went fairly well apart from the front end bearing which couldn't keep a hold of it's balls! Each time one was put back another dropped out! In the end (got a bit grumpy) I wound up distorting the brass cage and as far as I was concerned that was the end of that bearing! The replacement arrived pretty quickly and went in no bother after a stint in the freezer.

I was quite worried as to how well the drum would sit when placed back into the firebox (as it -firebox- did take a beating to get it apart!) but it seems to have gone O.K- no grinding anywhere, the drum seems to rotate freely and most bolt/screw holes lined up pretty well!

All in all I'm happy with how it's turned out despite some shoddy painting!
But it is still to be tested and fingers will have to be crossed until it is!

Anyhow here's some pics!