where to get cheap delrin/acetel rod slices

[Gazz292]

i need some black delrin/acetel rod for the project i bought my lathe for (replica german electric train controllers)

i need some 120mm diamiter rod, and judging by the price of the 100mm stuff on ebay, it's out of my price range,

the part i need them for would be a simple disc, 120mm diamiter by 25mm wide, and i need 6 or 7 of them in total,

anyone know where i can get off cuts of this stuff in/near the size i need? or know of something else i could use, thinking ice hockey pucks, but dont even know their size, let alone what they are made of,

[Swarfing]

Gazz

At that size you would be better off buying it in sheet form, it will work out much cheaper.

[Bluechip]

Bearing in mind there ain't no such thing as cheap ... rod or sheet.

Black HDPE or PVC sheet is less than Delrin/Acetal ..

EG:

http://www.directplasticsonline.co.uk/HDPESheet/Black/25mm/

But if it needs to be acetal ...

No Idea.

BC

[Pete.]

I bought my acetal from directplasticsonline. I got 100mm of 150diameter rod for £40 delivered, but when it arrived it had a note saying their bandsaw was out of action and they hope I don't mind but they sent me a 200mm long off-cut because they didn't want to delay my order.

Nope - I didn't mind

Looking at their site, their Delrin is limited to 100mm diameter but they'll do you 250mm of 125mm dia black acetal for £62 plus delivery. HDPE is half the cost.

Gazz

At that size you would be better off buying it in sheet form, it will work out much cheaper.

Can't even get close with sheet vs the cost of rod on that site. You could part 7 pieces 25mm thick from 250mm of rod but to do it in sheet you'd need to spend at least 50% more on material then find a way of cutting 120mm discs from it.

[andyf]

Davis Industrial Plastics show 120mm diameter x 250 mm of black acetal rod (generic Delrin) at £45.72 - second iten down in the right-hand column here: http://www.shopforplastic.co.uk/acetal-rod-110---200mm-13-c.asp . Their delivery charges start at £1.95, with a maximum of £17 for big stuff.

I bought some Tufnol from them once, and found them good to deal with.

Andy

Edit: just noticed that their prices don't include VAT, so £45.72 becomes £54.87.

[Gazz292]

yikes, even more expensive than i thought,

it dosent need to be any particular material to be honnest, but it needs to be able to take a threaded rod inserted into the end... for the lever, and a series of shallow holes drilled in the side for a sprung ball bearing to press into to give notches as the lever is moved forwards and backwards,

i made a mock up from wood last night at 75mm diamiter, but the bearing chewed the wood up as the lever was moved so i soon lost the notches,

never thought of using sheet, seems that could be more expensive tho, and a 120mm hole saw would deffo be expensive,
tho i could do it how i did the wood one, draw the circle, use the chop saw to rough it out, then mount it in the lathe via a hole in the centre and a bolt through it, then round it off with the lathe,

but i think 120mm would be too big for my little lathe, i'd deffo have to take the comound slide off to get a tool anywhere near it, so i rekon getting it already cut is my best option.

[Gazz292]

Changed my mind on the plastic.....

Been playing with my lathe, and made a handle out of some alli bar i had, and it machined so nicely i love the stuff, only problem i have is parting off, still got a lot to learn,

i was hoping the plastic would be cheaper than alli, but i'm not sure it is, and should be easier to find off cuts of alli bar,

only problem i'd have is parting off the slices, that's the reason i was thinking plastic, as that stuff parts off pretty easily, but alli has a tendancy to dig in, or it does in my hands, and it takes me ages to get through a 1 inch diamiter bar, so almost 5 inches of bar and i'd have no chance.

and a really silly reason i was thinking plastic, it comes in black, and that's what the controls are, but paint will do on alli, or even anodizing,


This is what i'm trying to make, very simple, but it's the mechanics below that will be harder to replicate, for the notches and varying resistances you push against,

i have the technical drawings for the controls, sent to me by someone who works in the tech department at DB, so i have most measurments, as well as the forces in newton meters for each notch, distance between notches and so on,

i just need to get the raw materials and get making.

[David Jupp]

May well be cheaper to purchase ready made knobs from one of the various companies offering 'standard parts' ...

[Pete.]

I think the plastic is needed for the bits below the ruler, not the knobs on the end of the stalks.

[David Jupp]

Note to self - read the detail !