The upcut bit's spiral direction allows for great chip ejection from the cut making it the perfect router bit for plunge cut mortises.  This bit ejects the wood chips out of the way of the router bits point making the plunge go nice and easy with less chance of bit wander.  It is fine for any hole or opening that will not be seen.

Why not just use a straight router bit? Well, that's an easy one.  The spiral bit's geometry and top point allow you to plunge into your work like a drill.  Our solid carbide spiral bits begin life as extra-hard C4 micro-grain cylindrical carbide blanks. We then use sophisticated 6-Axis C.N.C. grinding machines to grind their spiral geometry.  The precision of the spiral and hardness of carbide allows for a very sharp edge and typically longer edge sharpness. A straight bit can't compete with that.

In this photo, you can see that I used the upcut bit for the U and the downcut for the D.  The D has a much cleaner edge with minimal tearout (excluding the fact that it is freehanded and I have a hard time going in a straight line without a jig), while the U has a larger amount of tearout.

Solid carbide spiral router bits cause confusion.  What is the difference between upcut, downcut, or the compression up/down spiral router bit that does both?  Do I need all of them in every size?  Why can't I use one for every job?  Why not just use a straight bit?

Certain items, such as long fluorescent tubes (3ft and above) can only be transported by courier due to the length and delicate nature of the product. Unfortunately as a small business we are unable to cover the costs for this. These products are pre-selected for an extra shipping charge of £7.95 ex VAT by our website. If you order is over £45.00 delivery will be free of charge.

Our solid carbide spiral router bits are designed to provide remarkable performance and durability. They quickly slice through hard or soft wood, plywood and composites such as MDF or particleboard. Manufactured using state-of-the-art computer-controlled machinery; these micro-grain carbide cutters feature our optimal helix design and a stronger body that reduces vibration and lasts up to 300% longer than regular router bits. Unlike straight router bits, Infinity solid carbide spiral bits feature a helical spiral design that is continuously in contact with the workpiece, producing smoother cutting action and the cleanest results possible.

The compression (upcut & downcut) spiral bit creates a great edge on the side of a board when you need both edges to be crisp.  Its spiral action pulls both sides into the center of the bit where it ejects out of the side.

Downcut bits don't clear chips as quickly as upcut bits but their downcut geometry pushes wood fibers down into the cut and leave a nicer quality top surface on your workpiece. They do require a slower feed rate. When used in a router table downcut bits actually push your material up.

Delivery is free within the UK when you spend over £45.00. We are closed on Bank Holidays. Shipping and Handling: We will action your order either the same day or the day after you place it with us, assuming it is a working day. (Monday to Friday 8.55am to 5:00pm) If you are purchasing from outside the UK please contact us before ordering, as there will most likely be additional shipping costs. Unfortunately, if a large parcel needs to be sent to the Scottish Highlands or an offshore Isle such as Northern Ireland or the Isle of Mann via a courier there will be additional charges. Please contact us before ordering. Please note - We are unable to accept responsibility for damaged items on Export orders. Alternatively, we will contact you on receipt of your order. Smaller deliveries that can be sent via Royal Mail will incur no extra charge. Delivery Schedule: We try to despatch your order the same day we receive it. (Monday to Friday) We will deliver your order free of charge if your total order comes to £45 or more, otherwise the delivery charge is just £4.50. We will deliver to you either by Royal Mail, or by parcel carrier, according to weight and value of the order. Certain items, such as long fluorescent tubes (3ft and above) can only be transported by courier due to the length and delicate nature of the product. Unfortunately as a small business we are unable to cover the costs for this. These products are pre-selected for an extra shipping charge of £7.95 ex VAT by our website. If you order is over £45.00 delivery will be free of charge. Delivery is usually within 5-7 days or sooner depending on the time of day we receive your order.  We are unable to despatch orders at weekends and bank holidays. In the event that we are out of stock for a particular item, we will send everything but that item to you. Once the item comes into stock, we will then complete your order, at no extra delivery cost to you. If you require an item urgently please call or email us with the 'item code' and we will advise immediately if the item is in stock. Next day deliveries: -  We offer a next day delivery service - Please note, orders must be placed before 2pm to guarantee delivery for the next WORKING day. Next day deliveries do not apply to weekends or Bank Holidays. If there is an issue with stock we will let you know ASAP so you can decide if you would like to cancel. Our next day delivery charge is only £12. Back Orders: If your item is not in stock, we will back order for you. We will always email you with the option to cancel the order if you would rather not wait. If you need something urgently give us a call to check stock - Please have the item reference to hand as this will help to speed things up. We have been trading online now for over 19 years and have a feedback score of 4.5 out of 5. This shows our determination to ensure every order is processed as quickly and efficiently as possible. If you have any questions please do not hesitate to get in touch - [email protected] - 01763 661650.

Upcut bits pull chips up and out of the kerf for faster cutting. This type of bit is ideal for high-volume shops but the workpiece must be securely clamped in place to prevent lifting. For work requiring a finer finish consider a downcut spiral bit.

Next day deliveries do not apply to weekends or Bank Holidays. If there is an issue with stock we will let you know ASAP so you can decide if you would like to cancel. Our next day delivery charge is only £12. Back Orders: If your item is not in stock, we will back order for you.

Osram 64425 12 volt 20 watt G4 halogen capsule. Used for decorative light fittings and display furniture such as in the home or in shops. Lasts an average of 4000 hours. Osram brand now obsolete - A direct replacement will be supplied in exchange!

To determine a spiral bits direction of cut you need to look at it upside down. I don't mean you need to be upside down, but the bit needs to be upside down. So hold the router bit's shank in your hand with the cutting edge pointing towards the ground. Now spin the bit in a clockwise rotation. If the spiral is 'pushing' down you're holding a downcut bit, if the spiral is pulling up you're holding an upcut bit, there, that was easy. The other way to look at it is to hold the bits in your hand with the router tips facing upwards.  Reading the flutes from left to right, if the flute goes upwards to the right, then you have an upcut, and if the flutes go downwards to the right, then you have a downcut.  I drew really bad arrows on the photograph below to illustrate my point.  By now you've probably figured out that spiral bits were originally meant to work in an overhead (handheld) routing application, having been developed for guys with overhead CNC routers.

Osram 64425 12 volt 20 watt G4 halogen capsule. Used for decorative light fittings and display furniture such as in the home or in shops. Lasts an average of 4000 hours. Osram brand now obsolete - A direct replacement will be supplied in exchange!

Shipping and Handling: We will action your order either the same day or the day after you place it with us, assuming it is a working day. (Monday to Friday 8.55am to 5:00pm) If you are purchasing from outside the UK please contact us before ordering, as there will most likely be additional shipping costs. Unfortunately, if a large parcel needs to be sent to the Scottish Highlands or an offshore Isle such as Northern Ireland or the Isle of Mann via a courier there will be additional charges. Please contact us before ordering.

The downcut bit is the one I use more often though as I use it for cutting grooves, dadoes, and inlays.  This bit's fluting direction pushes the top grain on the wood down creating a cleaner top surface when you are doing grooves or inlays.  A lighter depth of cut is preferable with this bit.

We will always email you with the option to cancel the order if you would rather not wait. If you need something urgently give us a call to check stock - Please have the item reference to hand as this will help to speed things up. We have been trading online now for over 19 years and have a feedback score of 4.5 out of 5. This shows our determination to ensure every order is processed as quickly and efficiently as possible. If you have any questions please do not hesitate to get in touch - [email protected] - 01763 661650.

Alternatively, we will contact you on receipt of your order. Smaller deliveries that can be sent via Royal Mail will incur no extra charge. Delivery Schedule: We try to despatch your order the same day we receive it. (Monday to Friday) We will deliver your order free of charge if your total order comes to £45 or more, otherwise the delivery charge is just £4.50. We will deliver to you either by Royal Mail, or by parcel carrier, according to weight and value of the order.

Our solid carbide spiral router bits (both individually and in sets) provide remarkable performance and durability. Upcut bits pull chips up and out of the kerf for faster cutting. Downcut bits don't clear chips as quickly as upcut bits but their downcut geometry leaves a cleaner cut.

Please note: The recommended depth of cut for any single pass is 1/2 of the diameter of the tool. For example, if you are using a 1/4" diameter cutter you should only take a 1/8" depth of cut for any single pass. When used in a router table upcut bits actually pull your material down.

Delivery is usually within 5-7 days or sooner depending on the time of day we receive your order.  We are unable to despatch orders at weekends and bank holidays. In the event that we are out of stock for a particular item, we will send everything but that item to you. Once the item comes into stock, we will then complete your order, at no extra delivery cost to you. If you require an item urgently please call or email us with the 'item code' and we will advise immediately if the item is in stock. Next day deliveries: -  We offer a next day delivery service - Please note, orders must be placed before 2pm to guarantee delivery for the next WORKING day.

The solid carbide spiral bit uses a constant shearing action when making the cuts instead of a typical straight head router bit which basically smacks the bit edge against the wood over and over.  This does not mean that the spiral bit is your perfect go-to bit though.  Straight bits still have their place and typically get used more in most shops, not to mention that spiral bits have a higher up-front cost.

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One important thing to take note of is that if you do use the spiral router bits in a router table, then the downcut bit will actually push material towards your workpiece sometimes raising the workpiece off of the table.  It will still function the same making a clean-edged cut, but it does want to raise the workpiece up, so its important to use a good downward feather board system.  And please take light passes when using it in the table.  The upcut bit will actually pull the piece downward towards the table making it a little safer, but the tearout issue still exists.