Valve Guide Reamer 9.99 mm (.3933") – Engine Valve Guide Finishing Tool
Valve guide reamer Ø9.99 mm for precision finishing of valve guides in engine cylinder heads.
Used after drilling or rough reaming to achieve final size and surface quality.
Application:
Designed for sizing valve guides in automotive, motorcycle and industrial engines.
Correct guide diameter ensures proper valve stem clearance, stable lubrication and reduced wear.
What it actually does:
Final sizing operation with minimal stock removal.
Because the tool removes only a light finishing allowance, it improves bore accuracy and surface quality without pushing the guide oversize.
Diameter 9.99 mm (.3933"):
- Defines final valve-to-guide clearance
- At 9.99 mm, final guide size still controls valve stem support, so excess clearance can increase movement, oil consumption and wear
- No geometry correction — finishing only
Cutting design:
- Spiral flutes improve chip evacuation, which reduces scoring risk inside the guide
- Optimized cutting geometry lowers cutting force, which helps maintain bore straightness and roundness
- Stable cutting with low vibration supports smoother surface finish
Tool geometry:
The tool geometry is optimized for valve guide finishing operations, providing rigidity and stable cutting performance.
The reamer is equipped with a front guide pilot, which keeps the tool aligned with the existing bore axis during entry and cutting.
This reduces radial runout, limits bellmouthing at the guide entrance and improves size consistency through the full bore length.
Material & hardness:
Made from HCS (high carbon steel) with hardness ~HRC 62-64.
Fine carbide structure enables a sharp cutting edge, so the tool cuts cleanly and produces improved surface finish in light finishing passes.
- High edge sharpness → smooth reaming and low surface roughness
- Low cutting forces → reduced tool deflection and chatter
- Machine finishing → supports accurate final sizing
- Heat stability: HCS has low hot hardness, so excessive RPM quickly softens the edge
- Strict speed control required to avoid overheating
- Flood cooling is mandatory because oil removes heat and reduces friction
- Overheating above ~200°C leads to rapid dulling
- Limit: lower wear resistance compared to HSS
In practice:
Finishing tool only.
Recommended sequence: drilling → rough reaming → finish reaming.
The tool follows existing hole geometry, so final accuracy depends on previous operations.
Specification:
- Tool type: Valve guide reamer
- Diameter: 9.99 mm (.3933")
- Flute type: Spiral
- Guide type: Front pilot
- Material: HCS
- Hardness: ~HRC 62-64
- Application: Finishing / sizing
- Total Length: 175 mm
- Flute Length: 60 mm
Cutting performance:
- Low material removal
- High dimensional accuracy
- Smooth bore surface
- Requires continuous lubrication
Recommended cutting parameters:
- Cutting speed (Vc): 3–8 m/min
- RPM (Ø9.99 mm): 96–255 rpm
- Feed: 0.03–0.10 mm/rev
- Infeed: single-pass finishing
- Coolant: cutting oil (mandatory)
- Prefer lower RPM because HCS loses edge hardness when heat rises
- Flood cooling recommended because continuous oil flow improves tool life and finish
- Avoid dry cutting because friction can damage the guide surface
- Do not stop rotation inside the hole because trapped chips can mark the bore
- Ensure proper alignment because the tool follows the existing axis
Use for:
- Valve guide finishing
- Cylinder head repair
- Automotive, motorcycle and industrial engines
Limitations:
- Not for drilling
- Not for heavy stock removal
- Does not correct misalignment
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Shipping:
- FREE - we choose the cheapest and safest way at our discretion, we add the last one tracking number, because there may be several of them.
- 25$ - UPS / DPD / Fedex, recommended for Canada, direct shipping to your country, we choose a courier depending on the country.
- For EU customers: if you pay country import VAT on eBay, we add the VAT ID (IOSS) number to the shipping details, so parcels arrive faster without customs delays.
Please note: for orders over 150 EUR, import VAT and additional charges may be collected upon delivery.
Additional possible charges upon delivery may include:
Import VAT (if not prepaid through eBay)
Customs duties (depending on the product category)
Handling or customs clearance fees charged by the carrier
Local postal service processing fees.
- for US customers: You only pay applicable US state tax on eBay. We cover the import tax, so your parcels arrive faster without customs delays. There are no additional costs or hidden fees - you only pay the amount shown in your order. If the courier asks you for any additional payment, please contact us immediately.
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* All possible import restrictions given by Buyer’s state are up to Buyer’s expense.
* The Buyer agrees that Tokar tools (Seller) has no responsibility in case of restrictive import regulations for the goods above in the state of the Buyer.
* The Seller is not responsible for any additional costs (apart from already agreed) that may appear while importing goods.
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Answering the most common question we getting:
WHAT ABOUT THE WAR ? / What is your status during the war?
- we are working as much as it possible, our city was not heavily bombed, in many cities where there is no war, all business has returned to work to support the economy. So at this moment we can ship.
Can you do custom reamers?
- Yes, now we can consider the possibility of making individual orders. The production time is +/- 3 weeks after clarifying all the details.
Add that all the goods that are displayed in our Ebay store are in stock, we working, but all the men are registered in the military volunteer, we can be drafted into the army at any time, in this case, if you placed an order, but we did not send it, Ebay guarantees the full payment refun