Völund

Hi

Do anyone knows of som event or things to do this weekend nerby Ripley WV

Nerby = 2h by car

Thanks!

READY :D
http://www.youtube.com/watch?v=lYiw_B0W29c

Now the bottom roller is ready

The lower bronze bearings is ready
The reson for having these round is that the axis i fixed and the bearings i in the roller for the lower one.
The top could be rectangular. But i think i will go for ball bearing for the upper roll as seen in here before.


Los pictures

Casting ready

Have changed the plans, I will use solid bronze instead.

But at as i didn’t get it i decided why not try to cast it. That could be a fun mini project
Looked at several different mixtures decided to use 15% Sn as i only had tin for old tin soldiers. It had also 5-10 % lead.

So the mixture will be 85% Cu, 15% Sn and 1% Pb

Hmmm
Hard to calculate a force....
Backwards calc the "original" bronze bearing will stand 7637 kg for max dynamic design (failure is another thing this is calculated for higher speed design and usage a long time)
Maybe start looking after some solid bronze

No comments from anyone using ball bearing for the upper roll. Supose the force should be similar or greater on this one due to that the drive is on this one and rolled metal is plastic...

Have made som reserch:

Sintered bronze can stand 10-20N/mm2 and redmetal (bronze) can stand 60 N/mm2 in dynamical force (velocity <2 m/s)
For static force it is 50 N/mm2 (redmetal 90 N/mm2) (for velocity <0.01 m/s i have 0.02 m/s)

For my case the roller should stand for 1630 kg (3 593 pounds) dynamic
Or 4073 kg static (8 979 pounds)

Sombody that have an idea about the force.... for a 2" roll

Regarding the sintered bronze i do not know if it will not stand the pressure.
Regarding ball bearings i have seen several (like DIDTAS, Old Guy and The BLU Crusher) using them to the upper rolls. Pressure should be the same.
If talking high pressure suppose roll/needle bearing would be the best .
Staying to the original design is of cause good. But i'm having a hard time to finding bronze to a reasonable cost nearby. And then a redesign can be appropriate B)

Hi again
Back to the bearings, found some oil bronze bearings. Maybe these could work. Slightly smaller in dimension, 20 mm shaft and 20 mm long but ready
Any one knows if these will stand the pressure.
As i understand these ar made of sintered bronze. So they don’t need any lube hole, and are pre lubricated. But i suppose not as hard as ordinary bronze ?
Does anyone have some experience of oil bronze bearings for low rpm and high force....

According to McDonald mild steel should be fine, although I used some higher carbon shafting I already had. I wouldn't go smaller than 2" on the rollers. The smaller diameter would give you a steeper climb angle and not have enough "bite" to pull the stock through unless you reduced the stock in very small increments with each pass. I used bronze bushings inside the lower roller. I don't think pillow blocks would work well on the lower roller because of clearance problems. I really recommend getting the Hugh McDonald plans and stick close to the basic mechanics of it, although I think you can be flexible in the roller drive speed reduction.

Thanks for the answer.
Nice machine

Made a "belt" hammer for a while ago.

The hammer realy helps making Pattern welded steel
Now i found another electrical motor and need to practice some turning work

Planning to make the rolls the same size.
Are you using mild steel to the rolls. >Have some carbon steel avaible at a diameter of 1 3/4"
Are you using brass for the lower roll. I have some pillow blocks i will try to use.

Hi
Thinking of building a rolling mill?
Read somewhere that there was a size difference between the upper and lower "roller"! Why?

// :rolleyes: