I have just finished making my lamination grinder.

As the following photos illustrate, I used an 8" bench grinder as the power source.

The grinder is a belt sanding attachemnt which is made here in Australia. It is called a Multitool 362.

Here is a link to a video clip on You Tube:

Here is a link to the distributors of the Multitool in the USA:

Oops! I will try again later.

No links!

Let's try this.

Or this:

And this:

I think I am getting the hang of this.

The first photo was view of the lam grinder from the rear.

The second photo was view of the lam grinder from the front, showing the mechanism for adjusting the ramp height, the speings to keep the ramp under some tension and means of locking the ramp at a fixed height.

This pic shows how I lock the height of the ramp using a win (or butterfly nut, two washers and a spring washer, in conjuction with the springs.

Anyone would think I cannot spell common words, which shows how much I rely on the spelling checker in Word and Outlook.

It is not a 'win' nut it is a 'wing' nut. The wing nut, two washers and a spring washer are used in CONJUNCTION with the springs.

This pic is a close-up of the wing nut, spring washer and the flat washers. This locks the threaded rod a fixed height which means I can vary the height by a few thou of asn inch.

This pic shows the winding mechanism I use to adjust the height of the ramp and the washers and wing nut which I use to make fine adjustments to the height of the ramp and lock the ramp in position.

This pic shows the lamination grinder from the side. The large pully which attaches to the bench grinder has a plate which is bolted to the pulley and to which a sanding disc is attached.

At this time I have no need for a fixed disc sander so I have not attached the plate.

The small pully is the one which I use to grind the lams. It is a rubber pulley and it works quite well.

Today I ground three home made carbon lams to the required thickness, 0.9mm (about .035") and one parallel action boo lam to 1.85mm (about 0.072") in about 45 minutes. To do this work by hand would take me about five hours.

Now hopefully I will be able to provide some links.

This link should be to a video on You Tube.

I guess not. So here is the link in plain text:

http://au.youtube.com/watch?v=DVujiTB9ftc

Here is a link to the distributors of the Multi tool 362 in the USA:

http://ausmultitool.com/

And here is a link to the web site of the Australian company which distributes the various Multi tool models and all the spare parts etc.

http://www.jwross.com.au/

I will post some more pics if required. But for the moment some observations.

First and foremost is the objective of this exercise. I wanted to build a lam grinder which would only be used for grinding lams for bow limbs. My lams are all 1.4" wide and the sanding belt is 2.0" wide. This is ideal for my purposes as I only build double carbon longbows or hybrids. If I wanted to grind lams for recurve lims I would have purchased the Multitool 364 with the 4" belt.

Until now I used to reduce my home brew carbon lams to the required thiskness by hand. It took about an hour per lam to do this. I also reduced my parallel bamboo lams to the required thickness by hand. I machined them to about 0.100" and then I woul scrape and sand them to about 0.072". This would take about two hours per lam.

The time saving has been excellent.

The combination of an 8" bench grinder and the multitool makes for a relatively cheap and highly effective lam grinder. I would not recommend that you use a 6" bench grinder, even though the kit includes the bushes for a 6" grinder shaft.

I made a support for mine because I have a small work shop which is already over crowded. I do not have the room for a shop vac. So I did not build a dust hood as part of the lam grinder. Instead I put wheels on the support, turning it into a trolley, and I move it out of the workshop to grind the laminates.

I do not know how good other lam grinders are which do not have a powered feed mechanism, but I had to work out the best method of moving the lams through the gap between the sanding belt and the ramp.

I adjust the gap so that the lam moves the sanding belt (with the grinder switched off) and then I lock the height of the ramp. I then move the laminate through the gap in one smooth pass.

I experimented with sanding one half and then the other half, working from each end. This was not satisfactory because I then had to drag the lam back out of the gap. This caused mild 'chatter' which did not produce a flat lam.

I experimented with moving the lam backwards and forwards but this also induced 'chatter and did not produce a smooth lam.

So I have settled on moving the laminate through the gap in one smooth pass. I measure the thickness at several points along the lam and on both edges with a digital caliper.

I find thatif the thickness is within a few thou of what I want I can gradually reduce the thickness without adjusting the gap.

In conclusion I would like to note that this grinder works very well. It is inexpensive to build if you have an 8" bench grinder and much cheaper than a manufactured drum sander.

I welcome any questions from people interested in building one. I would also like to see pics of any lam grinders which have been built using a bench grinder as the power source.

Cool idea Norman! Good to hear from you it's been a while. This will really up your production ability. Galen

For those people who have had a look at this thread, you may be interested in the following thread. It shows a lam grinder made using a bench grinder and a Multitool 362, but with the lams fed through vertically.

http://www.ozbow.net/phpBB3/viewtopic.php?f=34&t=7182

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