Expect about $100 with shipping for a new screw wheel.
$100 for a plastic gear? I'd say this is a perfect candidate for 3-D printing... Check-out if the old gear can be scanned, retouched and reproduced, I
bet this would be less expensive.
Robert stoichiometric_steve - 19-12-2011 at 13:01
well yeah, it's about 50 EUR. i find that disturbingly expensive.edgecase - 22-6-2012 at 04:52
The "screw wheel", technically in north american english, it is a worm wheel, which meshes with a worm gear on the shaft of the motor.
It looks like a manufacturing defect, either the plastic is stretched very tight or solvents have caused it to shrink. Brass or even steel would be
better since it's such a low torque application. It's not like they aren't charging enough, and have to use "cheap" plastic.
I'm going to get mine measured up, the local industrial bearing shop has a set of gear pitch gauges. I would probably spend the $100 on a Buchi
original, except that based on the number of people with problems, it seems like a bad design.
Buchi seem to love using none standard parts where there's no need to.
There are coated labyrinth seals designed for high vacuum applications at a fraction of the price of theirs.
I get a buzz off the one I have, literally... because the capacitor's can or variac in there is leaking to ground. My mates flicks the breakers. A bit
of insulation would be nice for all that money.
[Edited on 22-6-2012 by peach]edgecase - 22-6-2012 at 16:58
So I just spent about an hour measuring up this gear, and searching for something that could be bored out on a lathe to make it better than original.
I may have found one made of Delrin (or steel, imagine! heat and solvent resistant!)
It's a bit odd, they are using a 4 thread worm gear, but instead of a matching worm wheel, they are just using a helical gear. My cheap angle finder
shows about 18 degree helix angle, 48 teeth, 2.6 inch O.D. 3/8 inch face width. I hassled the bearing shop this afternoon and got roughly 20
Diametral Pitch from one of their gear pitch gauges, 20 degree pressure angle.
I'm unsure if Delrin is a good material for the heat/solvents, though it is great for wear against the steel worm gear. Steel gear might be just fine
too, there's almost no torque involved in spinning a flask in water or oil. Thoughts?
[Edited on 2012-6-23 by edgecase]chemrox - 23-6-2012 at 01:04
I have motors. p2p me an I can arrange something with you. I bought a bunch of condensors, stands and motors a few years ago. I plant to assemble
rotovaps and sell them. The stand alone motors are "R" types and I have a couple of R-11 stands. You could pull the gear out of a motor I have that
needs to be re-packed with grease.
Buchi worm gear new or repaired
spankyetal - 21-6-2020 at 10:36
the gap damage in the worm gear face is a common occurrence. 66% of used R-111 drives had these damages or gaps, As of 2020 Buchi sells them for
$75.00. But there is a $120.00 minimum.
You can reach Buchi US to get their downloadable order form to order a new gear at:
ordermanagement@buchi.com or fax to 302-652-8777.
You can place an order through your local Distributor such as Fisher Scientific or VWR.
Repairs can be kept below $25.00 using a clay mold, epoxy resin and Dremel grinding touch-up. So far so good. TextTextDavidJR - 21-6-2020 at 11:29
Repairs can be kept below $25.00 using a clay mold, epoxy resin and Dremel grinding touch-up. So far so good.
Maybe an epoxy putty like milliput would be good for this?Heptylene - 21-6-2020 at 23:49
Maybe you could make a new tooth from thick plastic plate using a jewelers saw and some files? For $100 it's worth the effort.Dr.Bob - 22-6-2020 at 06:38
There is someone on here who made me some replacement gears, I will ask him to check with you.
OldNubbins - 22-6-2020 at 12:37
Looks like this thread was necrotized, but for future reference, I have some replacement gears I can send for the price of shipping or they can be
ordered less than $15 each from BMC3D. I also have the 3D model if you want to print your own.johnsonnamedborris99 - 3-11-2021 at 02:19
Looks like this thread was necrotized, but for future reference, I have some replacement gears I can send for the price of shipping or they can be
ordered less than $15 each from BMC3D. I also have the 3D model if you want to print your own.
i have been looking for this worm wheel for mine too. could i get a copy of the file? if you still have another one you are willing to sell i will
take it off your hands ? MOF guru - 2-3-2022 at 22:18
Looks like this thread was necrotized, but for future reference, I have some replacement gears I can send for the price of shipping or they can be
ordered less than $15 each from BMC3D. I also have the 3D model if you want to print your own.
We have the same problem with our Buchi rotavap.
Can anyone advise which exact type of helical gear it actually is from BMC3D?
Many thx in advance!Dr.Bob - 3-3-2022 at 20:15
That design was for a R-114 I believe. If you are in the US, he might be willing to ship you the part for postage and such. If not, I might have
some spare parts that would work, but I will be out the next week or so. If you are in the US and can't find the part, send me a note, and I will
get back when I can.MOF guru - 4-3-2022 at 10:38
Thanks for your fast reply. I am looking for one for RE-111. From the manual it is part no. 00565. I am located in Germany/Switzerland, hence it would
probably be easier to exchange the size/particular type (e.g. Order number/Description) or the even the 3D Model of the helical gear and I will search
for it here in Europe. As you have shown already, it is commercially available, although it is definitely „special“. Many thanks in advance for
all your help!
