Source of Imperial Flanged Oilite Bushes

I'm just starting out on a 1/2" Stovepipe Domestic Hit and Miss and the main bearings are spec'd as oilite. The kit originally came with two suitable bearings but its been through several peoples hands and accross the Atlantic, needless to say I now only have one bearing.

So does anyone know a UK source for the following spec bushes, I've tried all the usual suspects but the 5/8" ID ones all seem to be either 3/4" or 7/8" OD

5/8" ID

13/16 OD

1.25 Overall length

Flanged ( not too worried about flange dims)

Failing that what is oilite like to machine, I've not tried it before and as its only the OD it won't affect the actual bearing surface. Or do I just make it out of a bit of SA660 Bronze?

Thanks, Jason

Hi Jason, the closest I found is 5/8 x 7/8 x 1 1/4 from http://www.bearingboys.co.uk/?catid=2568&att1=5%2F8&att2=7%2F8&att3=1.1%2F4&att4=

As it is only the OD you are machining, it should be fine, just machine slowly and don't let the bearing overheat, also I suggest not using any coolant as this will potentially be absorbed by the bush.

cheers

CB

Hi Jason,

Why not make a brass (bronze?) bush for the 13/16" bearing? (Bush the bush).

Good luck.

Peter.

Hi Jason, this company lists them http://www.oilite.com but I don't know if they deal direct, but these people http://www.bowman.co.uk seem to sell oilite products and in thier catalogue they say if you can't find the size you require then contact them.

Hope it is of some help.

Regards Nick.

Jason, these bushes are easy to m/c being made of a sintered bronze material and are also porous so can absorb oil.

Tony

CB, yes those are the ones I found and what all the usual bearing suppliers list.

Peter T its a possibility but while im macining teh oD and Id of a sleeve I may as well just reduce the OD of a bearing, need to buy one anyway.

Nick, yest they seem to be available in the US, the drawings I have had "MSC" penciled onto them by one of the US owners so even they do them. I fear special order or non stock items may be ahigher price

Tony I was under the impression that you had to be careful not to smear the bronze particles and close up the pores, not an issue on the OD but something to watch when boring. Its also supposed to take the edge off HSS quite quickly so brazed carbide seems the way to go, the usual inserts being a bit "blunt" may be OK with the non ferrous ones.

I think I will get the 7/8" OD ones and reduce to suit, that will also allow me to get them closer to the 0.8125 as off the shelf are a few thou oversize. OK if I were pressing them into a hole but they are going under bearing caps so want to be exact. They are no more expensive than a bit of bronze and there will be less wotk as its for someone else.

J

Hi, yes I have heard that machining the bushes could smear the pores over, I don't know if that is real or imaginary. To be safe, perhaps rough with carbide and finish with a nicely sharpened HSS tool, I have found recently that HSS was ok when just removing smallish amounts off these type of bushes.

Tony

Jason, you will find all Oilite bushes are over size, the bore is over size too, they should be inserted with a stepped mandrel same diameter as the shaft, and the bearing will close down to the correct size, so the hole it goes in needs to be right size for the bearing, the manufacturer should have the dimentions,(similar to fitting needle roller bearings. Ian S C

But I'm hot going to be pressing them inas I won't be able to fit the crank shaft, they are held by bearing caps. I'm bang on 5/8 for the crank so the extra 0.0005-0.0015 should give a nice running fit. This is what they have to fit.

Edited By JasonB on 27/02/2012 07:33:36

Pulling the bearing cap down will have the same effect as pressing into a hole. The important no no, is reaming,thats what "smears" the pores of the bearing. To charge the bearing with oil, cover one end with a finger tip and fill with oil, put your thumb over the other end, and squeeze, or you can just drop it in some oil and leave it a while. Ian S C

If you "cannot" machine the bore, why do they offer "cored" bar in bulk??

Kwil,Not of oilite bushing, each individual bearing is moulded/ sintered and what you see is what you get, you are thinking of cored bronze (solid stuff), that you can machine, the idea of the hole is thatthere is no need to buy the bit that you arn't going to use. Ian S C

OILITE -

1. Use only boring to open out the cored hole to size.

2. DO NOT REAM, ever!

3. if bush overheats during machining and oil is lost, it can be re-impregnated by immersing in oil in a vacuum chamber.

4. Sharp HSS is recommended, carbide are NOT recommended - they are not sharp enough.

JD

Ian,

No, it is Oilite cored stock. As Jeff says, you can machine it with a sharp cutter CCGT inserts are more than sharp enough. Look at www. Bowman.co.uk

K

I don't think anyone said you "cannot" machine the stuff, I just said care needs to be taken not to smear the particles. Couple of pics of the surface close up here when smeared or correctly cut

http://www.lm-tarbell.com/machining_sintered_bronze.htm

And yes you can buy sintered bronze in solid and cored form to do what you want with.

J

Well I ordered the bearings Sunday night and they arrived 1st post yesterday and I have just come in from the shed after having machined them.

I can confirn what I said about them being abrasive to HSS, I only had to remove 1/16" off the dia over a 1" length on each, by the time the second bearing was done it looked a little shinnier than the first a sign of smearing. I then started to face back the flange and the bearing was getting pushed further onto the taper mandrel with each pass, a quick glance at the end of the tool and it had clearly lost its edge. Quick touch up and the job was completed.

I machined a couple of spacers out of the one remaining supplied bearing for other parts of teh engine and used the alloy/non ferrous tips from Glanze ( CGGT) and these cut as good if not better than the HSS and would obviously keep there edge for longer but did not do enough to confirm this. I doubt the standard CCGT ones would be upto it though.

It actually cut very easily with teh sharp tool a fine grain swarf that clung together with the oil, actually quite a bit of oil was pushed out of teh bearing as it was machined.

Anyway here they are in place with a nice slop free feel to the crank.