FA9101-20-P-2001 QnA.pdf

DEPARTMENT OF THE AIR FORCE

HEADQUARTERS AIR FORCE TEST CENTER (AFMC)

EDWARDS AIR FORCE BASE CALIFORNIA

18 Nov 2019

MEMORANDUM FOR WHOM IT MAY CONCERN

SUBJECT: FA9101-20-P-2001, Electronic Discharge Machine (EDM), Questions and Answers

1. Are products manufactured in Thailand acceptable?

a. No, products manufactured in Thailand are not acceptable for this acquisition.

2. Is a riser option required if the machine can cut from table -0 to 30 inches? This means that the upper head will come down to the table as well as submerge and cut 31.5 inches.

a. Yes, this option is acceptable as it is described.

3. In regard to Scope Section 2.1.3—it requires a minimal machining range of 31 x 23 x 20” submerged with an optional riser to extend the total Z-axis clearance to 30” with the addition of a 10” riser that the end user can install and uninstall as needed. My question is, would it be acceptable to offer a wire EDM that meets or exceeds the 31 x 23 x 20” machining range but offers a Z-axis stroke of .05-31” submerged instead? That way there is no need to have the end user install or uninstall the 10” riser. This would save considerable time and effort to make this change in the machine’s Z-axis capabilities.

Here the change is from 20” to 30” Z clearance and would be only a minute or two compared to many hours using the 10” riser. Plus no realignment required of the Z-axis to the main machine X and Y axes after the riser installation.

a. The intent is to be able to cut 30 inches with or without a riser. If the proposed system needs a riser to meet the requirement, it must be able to be installed and uninstalled by the end user and must not add error to the machine. The requirement in Scope Section 2.1.3 has not changed.

4. In regard to Scope Section 2.1.7--about using Linear Shaft Motors or Direct Drive ball screws in the axis drive system. Would it be acceptable to offer Plate Type Linear Motors instead of the Shaft Motors, as Plate type are a better design because there are only two items requiring alignment, the 2 Linear Guideways alone on each axis, not three required by the linear shaft motors the 2 Linear Guideways, plus, the Linear Shaft Motors.

Controlling the machines pitch, yaw and roll is much easier with two mechanical variables, not three, plus, the glass scale feedback on a linear motor is the true XY position of the wire to the work piece, and not the rotary position of the rotary scale of the shaft motor. Flat glass scale feedback provides more accurate positional accuracy.

a. The requirement in Scope Section 2.1.7 has not changed.

5. In regard to Scope Section 3.1--it requires 60 day delivery ARO. For a wire EDM of this size and the special 30” Z clearance will require more than 60 days. This will probably require 120-150 days to build and ship to the base.

a. The requirements document and the RFQ have been updated to reflect 120 days ARO for completion of the contract. This is firm due to mission requirements.