Sunlu filament welding assistant, the Randco Grip-a-Matic 2000

The brand new Sunlu filament welder is a great solution for splicing all those short end-of-roll tails you have lying about. However, imho, there is one big flaw and that is how to align, weld and extract the heated filament/joint without the hot splice getting all kinked and disjointed. Maybe they just did testing on perfectly straight filament strands. And, how did Sunlu expect a user to keep the 45 degree splice cuts aligned while the pfte sleeve is slipped over the joint?

There are now 2 versions. The newer (V2) version has spreader bars on the side to assist with filament insertion extraction. 

Enter the Randco Grip-a-Matic filament holder that helps you keep that kinky joint perfectly aligned until the filament joint splice cools enough to let the pfte sleeve get cut and removed.

Notice: The Sunlu filament welder gets quite hot, so carefully follow manufacturer directions to avoid burns. This filament holder requires sensible use and can't be held responsible for burns caused by user error or misuse.

Instructions for use 

1. Insert/slide each filament strand into the feeding ‘funnels’ at each side of the holder until they just meet in the middle opening
2. Trim each filament at opposing 45 degree angles so the joint is overlapping. This is very important for joint strength while rewinding on the spool and feeding into your printer
3. Slide the pfte tube onto one filament
4. Check for 45 degree overlapping alignment and slide the pfte tube over the other filament until the joint is held by the tube and the joint is centered in the tube
5. Preheat the Sunlu welding unit to the appropriate temperature, in my case PETG
6. Insert the joint into the Sunlu heated block and depress the welding cover and wait until it beeps
7. Per instructions, press in on each filament to ensure good joint melting/bonding
8. Carefully remove the hot, welded joint ensuring the joint doesn't become distended
9. You may need to apply light pressure to the filament sides (in the opening) to bring the joint into alignment if your filament is especially kinky. Remember, the joint is very, very hot when it comes out of the heating unit
10. When the filament has cooled, I like to slide the welded joint into one of the holder sides (it should cause the pfte tube to slide off the joint) so the welded joint is safe during pfte cutting and removal of the joined filaments from the holder
11. Then insert the pfte tube into the welder cutting tray and follow instructions for cutting
12. There are ‘spreader’ tabs that help to extract the filament from the holder, use caution to avoid breaking/bending the splice

Printing instructions

1. The .3mf is from Prusa Slicer and I chose to do a 2 filament print on an OPXL 5h
2. I used PETG since it isn't as brittle as PLA
3. I used a .15 layer height, input shaper, .4 nozzle
4. Supports are necessary due to the newly added spreader bars