Every so often, a 3D printed part will look like it printed successfully, but when removed from the build tray, it will crumble when any stress is put on it. Other times, the printer will repeatedly show a “failure to load” error. When this happens, the most common fix is simply to replace the tips in the print head. It’s important to do a tip change on your Stratasys 3D printer every 2000 print hours to ensure part quality is maintained.
The process we’ll explain here will apply to a Stratasys Uprint, Dimension 1200, and Fortus 250. The tip change process will be the same on all three of these machines.
Starting the Tip Change Process on Your Stratasys 3D Printer
First, put the machine in maintenance mode. On the main menu, select “maintenance”, then “machine”. From here the machine may go through a calibration step and move the head to the service position. Once the machine calibrates, select “tips”, then “replace”.
The machine will then unload any loaded material, heat the tips and put the head back into the service position. Make sure you have heat resistant gloves on as the chamber gets to be extremely hot. Remove the clear cover by pressing in the sides and pulling away from the head.
Remove the Old Tips
Next use your yellow 7/64” T handle Allen key and loosen the two screws for the each of the tips. Do not remove the screws – simply loosen enough to release the pressure of the clamps on the tips.
Use needle nose pliers to grab the tip shield and tip pull down to remove the entire tip. Repeat this process for both the support tip and model tip.
How to Identify Support and Model Tips
Unless you have a BST model printer, you will need to determine which tip is which. If you have a BST printer, both tips will be the same. One tip should have the word “soluble” printed on it; this is the support tip and will go in the left side of the head. The other should be longer and have a flared inlet; this is the model tip and will go in the right side of the head.
Put the tip shields on next by pressing the tip fully into the tip shield. You will notice the tip seats into a cutout in the tip shield
Install the tips in their respective sides by sliding the inlet of the tip into the grove in the heater block. Be sure the tab on the tip shield faces the rear of the machine and the tip is fully inserted into the heater block. Hold the tip in place with a gloved hand or needle nose pliers and tighten the screws. Tighten them to the point where you get just a little flex on the T- handle. Now replace the cover and close the door.
The screen should read “tips replaced?” select yes. This will zero out your counter in the printers software. The printer will then prompt you to add material. Insert both model and support material cartridges and select “Load both” on the printers screen.
Run the Tip Calibration
Once both materials have successfully loaded select “start part” and the printer will begin printing. The printer will automatically calibrate its Z offset and then print the XY calibration part. Once printing is completed, remove the tray and inspect the calibration part. Look for where the support road is best centered between model roads for both X and Y. It may be helpful to use a magnifying glass when inspecting the part.
On the printer’s screens, select “increment” or “decrement” to input the readings from the calibration part for both X and Y. Select “Done” when complete and the machine will return to the maintenance menu. Hitting “Done” one more time will return the printer to idle and you have finished replacing the tips on your printer.
The tips on any FDM 3D Printer are considered a consumable and need to be replaced regularly to ensure consistent print quality. If after replacing the tips, parts are still not as strong as they should be, there could be other parts that need to be replaced. Call Stratasys support at 1 (800) 801-6491.