Use both T18 and T19 tips on Hakko FX-888 FX-600 FX-601 $5 part

[capsicum]

I searched the forums and found no threads about T19 Hakko tips, and I searched deep into several of Hakko's international websites under multiple products.
What i found through some logical deduction and cross referencing of incomplete parts lists is that the FX-600 and FX-601 are the same product and the 8801 and 8805 (handpieces for the FX-888 FX-889) are likewise the same product, with one minor part change for all of them. The part is labeled "tip enclosure" and consists of a flared tube and securing nut.
Disclaimer, I have not mated any of them myself.

The Hakko part numbers are:
For T19 tips use B3720(tube&nut) or B5122(tube&nut)
For T18 tips use B3730(tube&nut) or B3469(just tube) and B1785(just nut)
Each part number is around $5 USA (in 2017) full retail straight from Hakko usa.
I'm not sure why they have multiple part numbers for each, it may be old and new styling(speed holes, chrome grill?), or it could be simple disorganization within the company which is implied by their haphazard info and documentation.   
  Much better than $75 for a whole unit.

Anyway why switch at all?
T18 are about 10g lighter and come in many styles. T19 having 10g more metal around the body have about 20% to 25% less thermal resistance and corresponding faster recovery rate.
Attached Image is for the FX-888 handpiece.

[tablatronix]

sorry for the necropost, thanks for the info

I also noticed that they refer to these as type M and L

HAKKO FX-8801? M type soldering iron for use with T18 tip series
HAKKO FX-8805? L type soldering iron for use with T19 tip series

And the flyer for the 889, says "NEW higher thermal capacity compared to previous tip series" 


Have you tried it yet ?

[Shock]

On this page:
http://www.hakko.com/english/products/hakko_fx8801_8805_parts.html#productNav

It says:
Use B5122 to change FX-8801 to FX-8805.

The T19 are the larger capacity tips. You will also need to either calibrate your station or adjust the temp to compensate for the tips temp offset, which you should be doing for some T18 tips anyway.

They also have some beefy tips in the T18 series, if you need that much thermal mass for doing big connections though a decent wattage mains iron works well.