Hi Everyone,
I’m replacing the bearings on my Hitachi P20SB and wanted to ask if a contact or non-contact seal is the most suitable option. Both have NBR seals on both sides, however, the non-contact seal doesn’t contact the bearings inner race unlike the contact option. I understand that the contact option provides better sealing at the expense of friction, speed and heat. I’m concerned that the extra heat generated by the contact seal might damage my planer as it’s only plastic. Plus the planers no load RPM is very close to the bearings limit speed reference.
Hi John,
I would say the non contact bearings are the recommended type as the speed will most likely be very close to the limit of a rubber seal. The non contact seal is designed to keep out dust but not moisture. As a planer is unlikely to see moisture the non contact type are fine.
I have seen a few dead green melted bodies laying around a few shaping bays. Usually a result of heavy use and bad bearings. I would keep friction and heat to a minimum on a Hitachi. Your to be commended for having sense enough to change bearings before you melt the housing.
Thanks for the replies, I’m going to go for the non contact type 
I need to replace bearings as well. Do you mind letting me know the part numbers and where you purchased them?
I went to my local bearing shop and asked for non contact sealed bearings. Part numbers below:
x2 6200 VV
x1 6000 VV
x1 608 VV
The part numbers vary slightly between brands but any decent bearing supplier will have crossovers
SKF would be 6200-2Z, 6000-2Z and 608-2Z for instance
NTN’s would be ZZ etc
How are your VV series bearings working out?
I am considering the VV/C3 bearings if I go with NSK bearings.
For others interest in bearings. I did a little research on SKF bearings. The 2RSL/C3 bearings are a good choice. The 2RSL/C3LHT23 seems to be a premium bearing replacement as it often lubricated specifically with Kyodo Yushi SRL grease.
Kia ora (Hi) Steve,
RSL sounds like a good option as it’s low friction but full contact seal. 1RSL should be sufficient if available. I wouldn’t bother with C3 which is extra clearance in the bearing. You only need that for very high speed or high temperatures (allows for expansion). Your planer is nowhere near the limiting speed. You will find that the C3 will most likely be more expensive so if available in a standard model you’ll save yourself some money.
Thanks for the info. Which side do you place the 1RSL side?, the outside (housing side) or inner (cutter and motor sides)?
Good to know about not needing the C3. I didn’t realize that the P20SB is nowhere near the limiting speed.
I gotta admit that I AI searched, “is a 2rsl c3 bearing a good option for a hitachi p20sb surfboard planer”. So that was my initial research. AI gives mixed results depending on a small variation of the query. For example, the above query resulted an answer stating the 2rsl is a non contact bearing, where in reality it is a low contact bearing.
Then I AI queried, “is a 2rsl bearing a low contact bearing” and AI answered yes. Go figure.
At any rate, good info, now I gotta decide, go overkill or with a good budget friendly 1rsl.
No problem I worked for a bearing distributor many sunrises ago, it’s funny what sticks in your knowledge base though! You could go 2RSL but if 1 side of the bearing is simply facing a housing that cannot be exposed to dust you might as well ditch the seal? You might find 1RSL harder to find so go with the 2RSL option. It won’t hurt either way.
What’s your opinion on mixing and matching bearing manufacters on the same planer?
What’s your opinion on mixing and matching different bearing specs even from the same bearing manufacturer, on the same planer.
Reason I ask is that I have seen bearing sets being sold with orange/red seals mixed with other bearings using a black seal.
No problem at all, sometimes different applications require different specs. For instance if a planer generated heat near the motor it may require C3 bearings in that location but standard clearance everywhere else. I wouldn’t worry if they are different manufacturers as long as they are known brands, they will all be made to a reasonable quality. I worked for SKF and can vouch for the quality, they controlled every aspect even down to owning their own steel mills. Having said that the Japanese brands were always very good as well.
Ok. I think I know know why the orange/redish replacement bearings (6200 series) are used on belt drive side (the non-exhaust side) of both the cutter head and the armature on the Hitachi P20SB.
I believe the orange/reddish seals are contact seals which are better at keeping out the fine foam dust. However, contact bearings create more friction heat. Using these bearings on the belt drive side is fine because they are embedded into diagram part number 38 End Bracket, which is made of an aluminum alloy. On this side you don’t have to worry about melting plastic.
I believe low friction sealed bearings are used on the exhaust side on both the cutter head (6000 series) and armature (608 series) because on that side, the bearings are embedded into the plastic housing. Therfore, you want to minimize friction heat to lessen the risk of melting the plastic housing.
So now, go get your bearings! Mix and match but always keep in mind to pay close attention to the bearing specs you use, particularly on the plastic housing side on planers.
Makes total sense. The wrong bearings on the plastic side is probably why the plastic melts. I bought a box full of melted housings and misc. parts a few years ago. I think this particular shaper though was working those “Green Machines” too hard.
OSS1,
Do you have any of those melted Hitachi housings for sale? If you have ne need for them, I could by the whole lot.
I’m looking for a replacement front base/shoe if you have an extra in the parts bin. They are hard to find even though the same front base/shoe design is used on the current P18 cordless.
It’s going to be sometime this summer before I am able to look through those parts. They are in storage on Maui.