Author Topic: Modifying Thicknesser extractor hood  (Read 2374 times)

Maker of Things

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Modifying Thicknesser extractor hood
« on: October 21, 2013, 08:37:17 PM »
I have a Jet 12" x 8" thicknesser in my workshop.  It is used to plane timber to a uniform thickness and can handle boards up to 12" wide.
The chip extractor, however, can barely cope with the chips from a 4" wide board and anything much wider and the extractor hood clogs up and needs cleaning.  Not good when a board is still being fed through!

So today I removed the hood and looked at ways to improve it.

This is the current set up.  The extractor hood outlet is only 1.5" bore.
If it ain't broke, you're not hitting it hard enough!

Maker of Things

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Re: Modifying Thicknesser extractor hood
« Reply #1 on: October 21, 2013, 08:40:16 PM »
To increase the bore I dug out a 4" soil pipe elbow and reformed one end of it with the help of a hot air gun.
Not a difficult task but the PVC gets soft all of a sudden and then takes quite a while, or a lot of blowing on it, to get it to freeze again.

I had to squash one end down to ensure that the thicknesser can still operate at its fill capacity without the new duct getting in the way of the raised planer head, or the exiting timber.
If it ain't broke, you're not hitting it hard enough!

Maker of Things

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Re: Modifying Thicknesser extractor hood
« Reply #2 on: October 21, 2013, 08:43:11 PM »
Next I used the soil pipe duct to mark the outlet profile on the extractor hood.
The Point of no return.  The unwanted tiny outlet was then cut out with a Dremel mounted circular saw blade.  That gave my workshop a good covering of black static 'snow'.

There was a lot of adjustment needed to ensure a good fit.
If it ain't broke, you're not hitting it hard enough!

Maker of Things

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Re: Modifying Thicknesser extractor hood
« Reply #3 on: October 21, 2013, 08:48:39 PM »
The modified soil pipe was then fitted to the extractor hood and carefully marked out and trimmed to fit.

It had to fit around the back edge of the planer head too and also provide tabs to bend around the inside of the hood for fixing.

There was much adjustment and heating and bending and reforming the soil pipe until I was happy with the fit and the clearance for the exiting timber.

This took the longest to sort out but finally I was able to pop rivet the hood to the soil pipe tabs and then apply sealant to the inside of the join.

The exit now also points in the right direction for the straightest line to the chip extractor without needing too many bends in the very draggy flexible hose.
If it ain't broke, you're not hitting it hard enough!

Maker of Things

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Re: Modifying Thicknesser extractor hood
« Reply #4 on: October 21, 2013, 08:53:30 PM »
This is a side view of the finished assembly.
It shows the soil pipe falling below the hood and cut away to clear the back of the planer head.  That does, of course, leave a gap. 

To fill the gap I cut and shaped a piece of wood, as you do, and screwed and sealed it into the space.  It is shaped on the inside to provide a smoother line for the air to flow past.

When the sealant has cured I will test it, maybe tomorrow.
If it ain't broke, you're not hitting it hard enough!

Maker of Things

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Re: Modifying Thicknesser extractor hood
« Reply #5 on: October 22, 2013, 12:35:43 PM »
The modified extractor hood has been refitted to the thicknesser and tested.

It was quite happy processing an 8" wide floor board with no blockages!

Success! :D
If it ain't broke, you're not hitting it hard enough!

Maker of Things

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Re: Modifying Thicknesser extractor hood
« Reply #6 on: October 22, 2013, 12:37:00 PM »
This is the clearance under the 'squashed' soil pipe.
Plenty of room for safety.
If it ain't broke, you're not hitting it hard enough!