Recent content by prdave00

Our current supplier of a plastic molded thermoplastic polycarbonate urethane part is asking if we'd consider "upgrading" from a Arburg model 270S400-100 U press to a Arburg 270C-400-90. Differences provided by our supplier are listed below. We do not want to completely re-validate the process...

Can anyone point me to any good references for designing urethane springs or know of any applicable posts in other forums? I've found information in catalogs such as that provided by Sorbothane, but these seem to be geared to helping one decide what might work from their catalog and not how to...

Try here: http://www.3dcadbrowser.com/download.aspx?3dmodel=48783 You should also look at the Visible Human Project at http://www.nih.gov/ for a fee. Or try SawBones for a fee. Good luck!

Thanks for all your help.

Chris & Pat: Obvious material degradation such as surface cracking hasn't been noted, but my recollection (and I'd have to check with my colleague) is that there was some permanent set after application of the loading cycles. The concern is that this yellowing is an indication that the material...

I've noticed done yellowing on some tubes extruded from 80A pcu I've been evaluating. These parts are being cyclically compressed (5-10% strain) in a saline solution maintained at 90-100 deg F. The cyclic loading is being performed in a room with fluorescent lighting. I don't see this yellowing...

I have a part that is made out of a titanium alloy per an ISO standard. The issue is the ISO standard covers both the Grade 23 and Grade 5 alloy in terms of chemistry and mechanical properties. Unfortunately the supplier of this part is either not being forthcoming or doesn't actually know what...

Now the attachment....http://files.engineering.com/getfile.aspx?folder=fa252168-9d19-45ef-a26b-6fffecce073b&file=deletemesoon3.PDF

Belanger: I'm not sure I see your point. Re FCF B, doesn't the actual center of the sphere have to meet both conditions, i.e., lie within the a .1 diameter cylinder and within the planes separated by .05? In my head, I'm imagining a cylindrical tolerance zone that is .1 in diameter and .05...

I'd speculate this is a way to distinguish some dimensions apart from the others. Maybe an "inspection dimension" or a dimension that changed from the prior revision of the drawing.

The attached drawing is similar to a part I have. I need to control the profile of a detente on a spherical part (think construction ball locator with a shoulder) tighter with respect to the center of the sphere (datum D) and the bottom of the shoulder (datum B) to control the surfaces...

I need to correct the post... Is there a difference between the following feature control frames (FCF) to control the position of a sphere using the attached intentionally incomplete drawing to put it into context? FCF A |TP|SØ.1|A|B| |TP|.05|B| FCF B |TP|Ø.1|A| |TP|.05|B| My instinct is...

Is there a difference between the following feature control frames (FCF) to control the position of a sphere using the attached intentionally incomplete drawing to put it into context? FCF A |TP|SØ.1|A|B| |TP|.05|B| FCF B |TP|Ø.1|A|B| |TP|.05|B| My instinct is that they are equivalent - the...

Will a rapid prototype work (SLA, SLS, etc.)?

I recently came encountered an "issue" with a supplier. A 3D surfaced feature with a profile tolerance is being checked using one of 2 CMMs depending on what's available. I should note that the entire sample population from each batch is checked using the same CMM (i.e., both CMMs cannot be used...