Riser Block for Mill out of Cast Iron Hollow Bar - where to get the Bar?

I wish to make a riser block to insert between the column of my HM-52G and the plate that allows the head to swivel. My plan so far is to source some Cast Iron Hollow Bar(because of its damping properties) and then have it precision ground to give parallel top and bottom faces. I would then bore holes down through the bar wall to allow the bolts to pass through, requiring me to purchase longer bolts to clamp the plate down onto the the riser/column.

I am looking to source a short length - approximately 150mm - of GRADE 2P Cast Iron Hollow Bar - with an OD between 300-325mm(12-13") and an ID between 200-225mm(8-9"). I have had quotes from Bohler-Uddeholm and Interlloy - quotes range from $320-400.:oo:

I am hoping other members might be able to point me toward an industry that uses this Hollow Bar. Not chasing a business name - though this would help - but a segment of industry that would use this size of Cast Iron. Only thing that springs to my mind would be Hydraulic Ram manufacturers/refurbishers.

Does anybody have any better ideas?:?

There is flocast

.:: Welcome To Flocast ::.

ADDED BY ADMIN

Clicking on this link :aro-u: resulted in this message using Google Chrome

http://content.screencast.com/users/...07-24_1255.png

Better? No
Cheaper? maybe
I'm guessing the bolts are about 175mm apart.
What about 4 x 175mm Dia columns?or some solid bar if you can find something the right size. It wouldn't be as good, but it maybe cheaper. Depends what sort of cutters you have in mind I guess.

RC. We only edit if we have to. This is a virus free site and if a post comes up with a warning then we will post that warning, the same as if a download is an excessive amount.

It is then up to the the members as to whether or not they proceed.

Try just the site listed and see what firefox does.

Lastly, I suggest that you go here:

https://www.woodworkforums.com/f90/fo...ad-them-33202/

Well two online virus scanners say it is safe..

Quote:

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Originally Posted by .RC.

Well two online virus scanners say it is safe..

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Hi .RC. and all,
I don't want to be adding any fuel to the fire, but I get a similar warning using Safari on a Mac, so I think that I'll give it a miss till it gets the all clear. Best wishes everyone,
Ropetangler

The link locked up my computer earlier, I had to restart it to get rid of it.

Back on topic, Mark are you doing away with the horizontal arbor support, raising the ram wont allow it to be used. Or are you doing some thing to extend it down as well.

Dave

Well you can ring flocast up... They manufacture cast iron bar and hollow bar

Flocast Australia Pty Ltd Factory 2, 105 Newlands Road
Coburg. Vic. 3058
Ph: (03) 9350-6333
Fax: (03) 9350-6999

The email address I have is [email protected] and the sales manager is Luke Drummond

.RC. - I doubt Flocast will be substantially cheaper than BU or Interlloy, but I will try them. I was trying to identify which industry sector would use this size cast bar, and then contact some businesses serving this sector in the hope of purchasing an off cut - rather than buying a piece cut to size from a retailer. I figured that a 6" length might not be all that useable - but it depends on who/what uses this hollow bar.

Dave J - I guess you could say I will be doing away with the horizontal spindle - because, as you said, raising the ram means the support would not align with the spindle. The riser would be removable of course - but it wouldnt be a job I would want to undertake too often. Some of the bolts are a bit painful when removing the ram and swivel plate - as you would remember. An arbor support extension would be possible - but I would evaluate this when I had the riser installed. I havent used the horizontal spindle at all - it is actually dismantled - I havent re-assembled it after tearing my machine down when I received it. Something else I need to get to.

Any more ideas of who/what would use this Cast Bar?

Does it really have to be cast iron, it would probably be easier and cheaper to get hold of hollow aluminium bar and the aluminium zinc alloys like 7075 are comparable in strength to steel. The resulting riser would be light enough to lift by hand (just). As it's attached to cast iron on both ends there's still mass to absorb vibrations

Thanks for everyone's suggestions. To make it clearer what I am proposing I have attached some 2D grabs of some 3D models I made. The square(ish) plate with 6 counterbored holes is the swivel plate for the ram/head. This bolts onto the top of the column - which only has perimeter mating - ie the swivel plate only contacts the column over a 25mm wide strip around the perimeter of the plate/column. The centre is hollow.

V1 drawings show my initial plan - get hold of some hollow bar, have it precision gound to give parallel faces, and then bore 6 holes for the bolts to pass through. Voila! A 150mm riser block. But the Bar is not cheap. :oo:

V2 drawings show a revision that I have come to after Graziano's suggestion about using different materials - considering the column and ram/head are already cast iron, does the riser need to be cast? I dont know - but it would be easier if I could use other materials. I already have some 25mm steel plate - add some hollow bar - say 36OD x 16ID - weld it all together, and then have it ground flat/parallel. The bolts would pass through the 6 pieces of hollow bar - removing the need to bore the holes after grinding. By using a larger bore size than the bolts require - 12mm - the required precision of the welding/assembly does not need to be that great - +-1mm would be acceptable.

What do you think? :? Does the riser need to be made from Cast Iron?

Have you tried a foundry for hollow bar?

A long shot, but you never know...

Wire your cad drawing to -
Eccles Foundry & Engineering. 41 Raymond Ave, Bayswater, WA 6053.( Phone 9370 5955 ) and ask for a quote for a casting in aluminium and cast iron. They do both.

Regards Bob.

Hi All,
Another suggestion would be to obtain or fabricate 2 concentric steel tubes of appropriate diameters for the required ID and OD of the riser block, and weld flanges with the required bolt pattern to either end, run conduit between the flanges for each hole, and then fill the internal cavity with concrete or grout. you could have an extra hole in one flange to use as a filling point, and if you thought it necessary you could have reo or even small bolts welded on the tubes in the concentric space in the manner of the home made lathe bed as featured in Dave Gingery's books. After chipping away excess grout/concrete from the filling point, you could surface grind the flanges to size and parallelism.
The concrete should give damping qualities and strength comparable to cast iron, and it could be done cheaply in terms of money if not in terms of time.
I hope that you can follow my tortured explanation of my idea for a solution for your problem, good luck what ever you decide to do.
Ropetangler

Thanks to .RC. and Anorak Bob for their foundry suggestions - I will contact a few here in the West and ask if they have any stock hollow bar AND get quotes from them to pour what I am looking for. I will probably get quotes for my V1 and something similar to V2 - minus the wall thickness differences.

Thanks to Ropetangler for his out-of-the-square solution. Your explanation was clear to me! :2tsup: I will investigate this solution in parallel with the foundry/cast iron option.

Thanks to all for their replies!

Any one else have any possible solutions?